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linux/fs/xfs/libxfs/xfs_refcount.c

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xfs: convert to SPDX license tags Remove the verbose license text from XFS files and replace them with SPDX tags. This does not change the license of any of the code, merely refers to the common, up-to-date license files in LICENSES/ This change was mostly scripted. fs/xfs/Makefile and fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected and modified by the following command: for f in `git grep -l "GNU General" fs/xfs/` ; do echo $f cat $f | awk -f hdr.awk > $f.new mv -f $f.new $f done And the hdr.awk script that did the modification (including detecting the difference between GPL-2.0 and GPL-2.0+ licenses) is as follows: $ cat hdr.awk BEGIN { hdr = 1.0 tag = "GPL-2.0" str = "" } /^ \* This program is free software/ { hdr = 2.0; next } /any later version./ { tag = "GPL-2.0+" next } /^ \*\// { if (hdr > 0.0) { print "// SPDX-License-Identifier: " tag print str print $0 str="" hdr = 0.0 next } print $0 next } /^ \* / { if (hdr > 1.0) next if (hdr > 0.0) { if (str != "") str = str "\n" str = str $0 next } print $0 next } /^ \*/ { if (hdr > 0.0) next print $0 next } // { if (hdr > 0.0) { if (str != "") str = str "\n" str = str $0 next } print $0 } END { } $ Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-06-06 10:42:14 +08:00
// SPDX-License-Identifier: GPL-2.0+
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
/*
* Copyright (C) 2016 Oracle. All Rights Reserved.
* Author: Darrick J. Wong <darrick.wong@oracle.com>
*/
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_shared.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
#include "xfs_mount.h"
#include "xfs_defer.h"
#include "xfs_btree.h"
#include "xfs_bmap.h"
#include "xfs_refcount_btree.h"
#include "xfs_alloc.h"
xfs: move error injection tags into their own file Move the error injection tag names into a libxfs header so that we can share it between kernel and userspace. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2017-11-01 03:04:49 +08:00
#include "xfs_errortag.h"
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
#include "xfs_error.h"
#include "xfs_trace.h"
#include "xfs_trans.h"
#include "xfs_bit.h"
#include "xfs_refcount.h"
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
#include "xfs_rmap.h"
xfs: convert refcount btree cursor to use perags Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
#include "xfs_ag.h"
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
xfs: create slab caches for frequently-used deferred items Create slab caches for the high-level structures that coordinate deferred intent items, since they're used fairly heavily. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
2021-10-13 05:11:01 +08:00
struct kmem_cache *xfs_refcount_intent_cache;
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
/* Allowable refcount adjustment amounts. */
enum xfs_refc_adjust_op {
XFS_REFCOUNT_ADJUST_INCREASE = 1,
XFS_REFCOUNT_ADJUST_DECREASE = -1,
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
XFS_REFCOUNT_ADJUST_COW_ALLOC = 0,
XFS_REFCOUNT_ADJUST_COW_FREE = -1,
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
};
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
STATIC int __xfs_refcount_cow_alloc(struct xfs_btree_cur *rcur,
xfs: pass transaction to xfs_defer_add() The majority of remaining references to struct xfs_defer_ops in XFS are associated with xfs_defer_add(). At this point, there are no more external xfs_defer_ops users left. All instances of xfs_defer_ops are embedded in the transaction, which means we can safely pass the transaction down to the dfops add interface. Update xfs_defer_add() to receive the transaction as a parameter. Various subsystems implement wrappers to allocate and construct the context specific data structures for the associated deferred operation type. Update these to also carry the transaction down as needed and clean up unused dfops parameters along the way. This removes most of the remaining references to struct xfs_defer_ops throughout the code and facilitates removal of the structure. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> [darrick: fix unused variable warnings with ftrace disabled] Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-08-01 22:20:34 +08:00
xfs_agblock_t agbno, xfs_extlen_t aglen);
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
STATIC int __xfs_refcount_cow_free(struct xfs_btree_cur *rcur,
xfs: pass transaction to xfs_defer_add() The majority of remaining references to struct xfs_defer_ops in XFS are associated with xfs_defer_add(). At this point, there are no more external xfs_defer_ops users left. All instances of xfs_defer_ops are embedded in the transaction, which means we can safely pass the transaction down to the dfops add interface. Update xfs_defer_add() to receive the transaction as a parameter. Various subsystems implement wrappers to allocate and construct the context specific data structures for the associated deferred operation type. Update these to also carry the transaction down as needed and clean up unused dfops parameters along the way. This removes most of the remaining references to struct xfs_defer_ops throughout the code and facilitates removal of the structure. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> [darrick: fix unused variable warnings with ftrace disabled] Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-08-01 22:20:34 +08:00
xfs_agblock_t agbno, xfs_extlen_t aglen);
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
/*
* Look up the first record less than or equal to [bno, len] in the btree
* given by cur.
*/
int
xfs_refcount_lookup_le(
struct xfs_btree_cur *cur,
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
enum xfs_refc_domain domain,
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
xfs_agblock_t bno,
int *stat)
{
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
trace_xfs_refcount_lookup(cur->bc_mp, cur->bc_ag.pag->pag_agno,
xfs_refcount_encode_startblock(bno, domain),
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
XFS_LOOKUP_LE);
cur->bc_rec.rc.rc_startblock = bno;
cur->bc_rec.rc.rc_blockcount = 0;
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
cur->bc_rec.rc.rc_domain = domain;
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
return xfs_btree_lookup(cur, XFS_LOOKUP_LE, stat);
}
/*
* Look up the first record greater than or equal to [bno, len] in the btree
* given by cur.
*/
int
xfs_refcount_lookup_ge(
struct xfs_btree_cur *cur,
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
enum xfs_refc_domain domain,
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
xfs_agblock_t bno,
int *stat)
{
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
trace_xfs_refcount_lookup(cur->bc_mp, cur->bc_ag.pag->pag_agno,
xfs_refcount_encode_startblock(bno, domain),
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
XFS_LOOKUP_GE);
cur->bc_rec.rc.rc_startblock = bno;
cur->bc_rec.rc.rc_blockcount = 0;
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
cur->bc_rec.rc.rc_domain = domain;
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
return xfs_btree_lookup(cur, XFS_LOOKUP_GE, stat);
}
xfs: add repair helpers for the reference count btree Add a couple of functions to the refcount btree and generic btree code that will be used to repair the refcountbt. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-05-10 01:02:03 +08:00
/*
* Look up the first record equal to [bno, len] in the btree
* given by cur.
*/
int
xfs_refcount_lookup_eq(
struct xfs_btree_cur *cur,
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
enum xfs_refc_domain domain,
xfs: add repair helpers for the reference count btree Add a couple of functions to the refcount btree and generic btree code that will be used to repair the refcountbt. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-05-10 01:02:03 +08:00
xfs_agblock_t bno,
int *stat)
{
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
trace_xfs_refcount_lookup(cur->bc_mp, cur->bc_ag.pag->pag_agno,
xfs_refcount_encode_startblock(bno, domain),
xfs: add repair helpers for the reference count btree Add a couple of functions to the refcount btree and generic btree code that will be used to repair the refcountbt. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-05-10 01:02:03 +08:00
XFS_LOOKUP_LE);
cur->bc_rec.rc.rc_startblock = bno;
cur->bc_rec.rc.rc_blockcount = 0;
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
cur->bc_rec.rc.rc_domain = domain;
xfs: add repair helpers for the reference count btree Add a couple of functions to the refcount btree and generic btree code that will be used to repair the refcountbt. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-05-10 01:02:03 +08:00
return xfs_btree_lookup(cur, XFS_LOOKUP_EQ, stat);
}
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
/* Convert on-disk record to in-core format. */
xfs: expose various functions to repair code Expose various helpers that the repair code will want to use. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-05-10 01:02:02 +08:00
void
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
xfs_refcount_btrec_to_irec(
xfs: make the record pointer passed to query_range functions const The query_range functions are supposed to call a caller-supplied function on each record found in the dataset. These functions don't own the memory storing the record, so don't let them change the record. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2021-08-11 08:02:16 +08:00
const union xfs_btree_rec *rec,
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
struct xfs_refcount_irec *irec)
{
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
uint32_t start;
start = be32_to_cpu(rec->refc.rc_startblock);
if (start & XFS_REFC_COW_START) {
start &= ~XFS_REFC_COW_START;
irec->rc_domain = XFS_REFC_DOMAIN_COW;
} else {
irec->rc_domain = XFS_REFC_DOMAIN_SHARED;
}
irec->rc_startblock = start;
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
irec->rc_blockcount = be32_to_cpu(rec->refc.rc_blockcount);
irec->rc_refcount = be32_to_cpu(rec->refc.rc_refcount);
}
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
/*
* Get the data from the pointed-to record.
*/
int
xfs_refcount_get_rec(
struct xfs_btree_cur *cur,
struct xfs_refcount_irec *irec,
int *stat)
{
xfs: validate btree records on retrieval So we don't check the validity of records as we walk the btree. When there are corrupt records in the free space btree (e.g. zero startblock/length or beyond EOAG) we just blindly use it and things go bad from there. That leads to assert failures on debug kernels like this: XFS: Assertion failed: fs_is_ok, file: fs/xfs/libxfs/xfs_alloc.c, line: 450 .... Call Trace: xfs_alloc_fixup_trees+0x368/0x5c0 xfs_alloc_ag_vextent_near+0x79a/0xe20 xfs_alloc_ag_vextent+0x1d3/0x330 xfs_alloc_vextent+0x5e9/0x870 Or crashes like this: XFS (loop0): xfs_buf_find: daddr 0x7fb28 out of range, EOFS 0x8000 ..... BUG: unable to handle kernel NULL pointer dereference at 00000000000000c8 .... Call Trace: xfs_bmap_add_extent_hole_real+0x67d/0x930 xfs_bmapi_write+0x934/0xc90 xfs_da_grow_inode_int+0x27e/0x2f0 xfs_dir2_grow_inode+0x55/0x130 xfs_dir2_sf_to_block+0x94/0x5d0 xfs_dir2_sf_addname+0xd0/0x590 xfs_dir_createname+0x168/0x1a0 xfs_rename+0x658/0x9b0 By checking that free space records pulled from the trees are within the valid range, we catch many of these corruptions before they can do damage. This is a generic btree record checking deficiency. We need to validate the records we fetch from all the different btrees before we use them to catch corruptions like this. This patch results in a corrupt record emitting an error message and returning -EFSCORRUPTED, and the higher layers catch that and abort: XFS (loop0): Size Freespace BTree record corruption in AG 0 detected! XFS (loop0): start block 0x0 block count 0x0 XFS (loop0): Internal error xfs_trans_cancel at line 1012 of file fs/xfs/xfs_trans.c. Caller xfs_create+0x42a/0x670 ..... Call Trace: dump_stack+0x85/0xcb xfs_trans_cancel+0x19f/0x1c0 xfs_create+0x42a/0x670 xfs_generic_create+0x1f6/0x2c0 vfs_create+0xf9/0x180 do_mknodat+0x1f9/0x210 do_syscall_64+0x5a/0x180 entry_SYSCALL_64_after_hwframe+0x49/0xbe ..... XFS (loop0): xfs_do_force_shutdown(0x8) called from line 1013 of file fs/xfs/xfs_trans.c. Return address = ffffffff81500868 XFS (loop0): Corruption of in-memory data detected. Shutting down filesystem Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-06-06 10:42:13 +08:00
struct xfs_mount *mp = cur->bc_mp;
xfs: Pre-calculate per-AG agbno geometry There is a lot of overhead in functions like xfs_verify_agbno() that repeatedly calculate the geometry limits of an AG. These can be pre-calculated as they are static and the verification context has a per-ag context it can quickly reference. In the case of xfs_verify_agbno(), we now always have a perag context handy, so we can store the AG length and the minimum valid block in the AG in the perag. This means we don't have to calculate it on every call and it can be inlined in callers if we move it to xfs_ag.h. Move xfs_ag_block_count() to xfs_ag.c because it's really a per-ag function and not an XFS type function. We need a little bit of rework that is specific to xfs_initialise_perag() to allow growfs to calculate the new perag sizes before we've updated the primary superblock during the grow (chicken/egg situation). Note that we leave the original xfs_verify_agbno in place in xfs_types.c as a static function as other callers in that file do not have per-ag contexts so still need to go the long way. It's been renamed to xfs_verify_agno_agbno() to indicate it takes both an agno and an agbno to differentiate it from new function. Future commits will make similar changes for other per-ag geometry validation functions. Further: $ size --totals fs/xfs/built-in.a text data bss dec hex filename before 1483006 329588 572 1813166 1baaae (TOTALS) after 1482185 329588 572 1812345 1ba779 (TOTALS) This rework reduces the binary size by ~820 bytes, indicating that much less work is being done to bounds check the agbno values against on per-ag geometry information. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2022-07-07 17:13:02 +08:00
struct xfs_perag *pag = cur->bc_ag.pag;
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
union xfs_btree_rec *rec;
int error;
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
error = xfs_btree_get_rec(cur, &rec, stat);
xfs: validate btree records on retrieval So we don't check the validity of records as we walk the btree. When there are corrupt records in the free space btree (e.g. zero startblock/length or beyond EOAG) we just blindly use it and things go bad from there. That leads to assert failures on debug kernels like this: XFS: Assertion failed: fs_is_ok, file: fs/xfs/libxfs/xfs_alloc.c, line: 450 .... Call Trace: xfs_alloc_fixup_trees+0x368/0x5c0 xfs_alloc_ag_vextent_near+0x79a/0xe20 xfs_alloc_ag_vextent+0x1d3/0x330 xfs_alloc_vextent+0x5e9/0x870 Or crashes like this: XFS (loop0): xfs_buf_find: daddr 0x7fb28 out of range, EOFS 0x8000 ..... BUG: unable to handle kernel NULL pointer dereference at 00000000000000c8 .... Call Trace: xfs_bmap_add_extent_hole_real+0x67d/0x930 xfs_bmapi_write+0x934/0xc90 xfs_da_grow_inode_int+0x27e/0x2f0 xfs_dir2_grow_inode+0x55/0x130 xfs_dir2_sf_to_block+0x94/0x5d0 xfs_dir2_sf_addname+0xd0/0x590 xfs_dir_createname+0x168/0x1a0 xfs_rename+0x658/0x9b0 By checking that free space records pulled from the trees are within the valid range, we catch many of these corruptions before they can do damage. This is a generic btree record checking deficiency. We need to validate the records we fetch from all the different btrees before we use them to catch corruptions like this. This patch results in a corrupt record emitting an error message and returning -EFSCORRUPTED, and the higher layers catch that and abort: XFS (loop0): Size Freespace BTree record corruption in AG 0 detected! XFS (loop0): start block 0x0 block count 0x0 XFS (loop0): Internal error xfs_trans_cancel at line 1012 of file fs/xfs/xfs_trans.c. Caller xfs_create+0x42a/0x670 ..... Call Trace: dump_stack+0x85/0xcb xfs_trans_cancel+0x19f/0x1c0 xfs_create+0x42a/0x670 xfs_generic_create+0x1f6/0x2c0 vfs_create+0xf9/0x180 do_mknodat+0x1f9/0x210 do_syscall_64+0x5a/0x180 entry_SYSCALL_64_after_hwframe+0x49/0xbe ..... XFS (loop0): xfs_do_force_shutdown(0x8) called from line 1013 of file fs/xfs/xfs_trans.c. Return address = ffffffff81500868 XFS (loop0): Corruption of in-memory data detected. Shutting down filesystem Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-06-06 10:42:13 +08:00
if (error || !*stat)
return error;
xfs_refcount_btrec_to_irec(rec, irec);
if (irec->rc_blockcount == 0 || irec->rc_blockcount > MAXREFCEXTLEN)
goto out_bad_rec;
xfs: refactor domain and refcount checking Create a helper function to ensure that CoW staging extent records have a single refcount and that shared extent records have more than 1 refcount. We'll put this to more use in the next patch. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-27 05:31:27 +08:00
if (!xfs_refcount_check_domain(irec))
xfs: validate btree records on retrieval So we don't check the validity of records as we walk the btree. When there are corrupt records in the free space btree (e.g. zero startblock/length or beyond EOAG) we just blindly use it and things go bad from there. That leads to assert failures on debug kernels like this: XFS: Assertion failed: fs_is_ok, file: fs/xfs/libxfs/xfs_alloc.c, line: 450 .... Call Trace: xfs_alloc_fixup_trees+0x368/0x5c0 xfs_alloc_ag_vextent_near+0x79a/0xe20 xfs_alloc_ag_vextent+0x1d3/0x330 xfs_alloc_vextent+0x5e9/0x870 Or crashes like this: XFS (loop0): xfs_buf_find: daddr 0x7fb28 out of range, EOFS 0x8000 ..... BUG: unable to handle kernel NULL pointer dereference at 00000000000000c8 .... Call Trace: xfs_bmap_add_extent_hole_real+0x67d/0x930 xfs_bmapi_write+0x934/0xc90 xfs_da_grow_inode_int+0x27e/0x2f0 xfs_dir2_grow_inode+0x55/0x130 xfs_dir2_sf_to_block+0x94/0x5d0 xfs_dir2_sf_addname+0xd0/0x590 xfs_dir_createname+0x168/0x1a0 xfs_rename+0x658/0x9b0 By checking that free space records pulled from the trees are within the valid range, we catch many of these corruptions before they can do damage. This is a generic btree record checking deficiency. We need to validate the records we fetch from all the different btrees before we use them to catch corruptions like this. This patch results in a corrupt record emitting an error message and returning -EFSCORRUPTED, and the higher layers catch that and abort: XFS (loop0): Size Freespace BTree record corruption in AG 0 detected! XFS (loop0): start block 0x0 block count 0x0 XFS (loop0): Internal error xfs_trans_cancel at line 1012 of file fs/xfs/xfs_trans.c. Caller xfs_create+0x42a/0x670 ..... Call Trace: dump_stack+0x85/0xcb xfs_trans_cancel+0x19f/0x1c0 xfs_create+0x42a/0x670 xfs_generic_create+0x1f6/0x2c0 vfs_create+0xf9/0x180 do_mknodat+0x1f9/0x210 do_syscall_64+0x5a/0x180 entry_SYSCALL_64_after_hwframe+0x49/0xbe ..... XFS (loop0): xfs_do_force_shutdown(0x8) called from line 1013 of file fs/xfs/xfs_trans.c. Return address = ffffffff81500868 XFS (loop0): Corruption of in-memory data detected. Shutting down filesystem Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-06-06 10:42:13 +08:00
goto out_bad_rec;
/* check for valid extent range, including overflow */
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
if (!xfs_verify_agbext(pag, irec->rc_startblock, irec->rc_blockcount))
xfs: validate btree records on retrieval So we don't check the validity of records as we walk the btree. When there are corrupt records in the free space btree (e.g. zero startblock/length or beyond EOAG) we just blindly use it and things go bad from there. That leads to assert failures on debug kernels like this: XFS: Assertion failed: fs_is_ok, file: fs/xfs/libxfs/xfs_alloc.c, line: 450 .... Call Trace: xfs_alloc_fixup_trees+0x368/0x5c0 xfs_alloc_ag_vextent_near+0x79a/0xe20 xfs_alloc_ag_vextent+0x1d3/0x330 xfs_alloc_vextent+0x5e9/0x870 Or crashes like this: XFS (loop0): xfs_buf_find: daddr 0x7fb28 out of range, EOFS 0x8000 ..... BUG: unable to handle kernel NULL pointer dereference at 00000000000000c8 .... Call Trace: xfs_bmap_add_extent_hole_real+0x67d/0x930 xfs_bmapi_write+0x934/0xc90 xfs_da_grow_inode_int+0x27e/0x2f0 xfs_dir2_grow_inode+0x55/0x130 xfs_dir2_sf_to_block+0x94/0x5d0 xfs_dir2_sf_addname+0xd0/0x590 xfs_dir_createname+0x168/0x1a0 xfs_rename+0x658/0x9b0 By checking that free space records pulled from the trees are within the valid range, we catch many of these corruptions before they can do damage. This is a generic btree record checking deficiency. We need to validate the records we fetch from all the different btrees before we use them to catch corruptions like this. This patch results in a corrupt record emitting an error message and returning -EFSCORRUPTED, and the higher layers catch that and abort: XFS (loop0): Size Freespace BTree record corruption in AG 0 detected! XFS (loop0): start block 0x0 block count 0x0 XFS (loop0): Internal error xfs_trans_cancel at line 1012 of file fs/xfs/xfs_trans.c. Caller xfs_create+0x42a/0x670 ..... Call Trace: dump_stack+0x85/0xcb xfs_trans_cancel+0x19f/0x1c0 xfs_create+0x42a/0x670 xfs_generic_create+0x1f6/0x2c0 vfs_create+0xf9/0x180 do_mknodat+0x1f9/0x210 do_syscall_64+0x5a/0x180 entry_SYSCALL_64_after_hwframe+0x49/0xbe ..... XFS (loop0): xfs_do_force_shutdown(0x8) called from line 1013 of file fs/xfs/xfs_trans.c. Return address = ffffffff81500868 XFS (loop0): Corruption of in-memory data detected. Shutting down filesystem Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-06-06 10:42:13 +08:00
goto out_bad_rec;
if (irec->rc_refcount == 0 || irec->rc_refcount > MAXREFCOUNT)
goto out_bad_rec;
xfs: Pre-calculate per-AG agbno geometry There is a lot of overhead in functions like xfs_verify_agbno() that repeatedly calculate the geometry limits of an AG. These can be pre-calculated as they are static and the verification context has a per-ag context it can quickly reference. In the case of xfs_verify_agbno(), we now always have a perag context handy, so we can store the AG length and the minimum valid block in the AG in the perag. This means we don't have to calculate it on every call and it can be inlined in callers if we move it to xfs_ag.h. Move xfs_ag_block_count() to xfs_ag.c because it's really a per-ag function and not an XFS type function. We need a little bit of rework that is specific to xfs_initialise_perag() to allow growfs to calculate the new perag sizes before we've updated the primary superblock during the grow (chicken/egg situation). Note that we leave the original xfs_verify_agbno in place in xfs_types.c as a static function as other callers in that file do not have per-ag contexts so still need to go the long way. It's been renamed to xfs_verify_agno_agbno() to indicate it takes both an agno and an agbno to differentiate it from new function. Future commits will make similar changes for other per-ag geometry validation functions. Further: $ size --totals fs/xfs/built-in.a text data bss dec hex filename before 1483006 329588 572 1813166 1baaae (TOTALS) after 1482185 329588 572 1812345 1ba779 (TOTALS) This rework reduces the binary size by ~820 bytes, indicating that much less work is being done to bounds check the agbno values against on per-ag geometry information. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2022-07-07 17:13:02 +08:00
trace_xfs_refcount_get(cur->bc_mp, pag->pag_agno, irec);
xfs: validate btree records on retrieval So we don't check the validity of records as we walk the btree. When there are corrupt records in the free space btree (e.g. zero startblock/length or beyond EOAG) we just blindly use it and things go bad from there. That leads to assert failures on debug kernels like this: XFS: Assertion failed: fs_is_ok, file: fs/xfs/libxfs/xfs_alloc.c, line: 450 .... Call Trace: xfs_alloc_fixup_trees+0x368/0x5c0 xfs_alloc_ag_vextent_near+0x79a/0xe20 xfs_alloc_ag_vextent+0x1d3/0x330 xfs_alloc_vextent+0x5e9/0x870 Or crashes like this: XFS (loop0): xfs_buf_find: daddr 0x7fb28 out of range, EOFS 0x8000 ..... BUG: unable to handle kernel NULL pointer dereference at 00000000000000c8 .... Call Trace: xfs_bmap_add_extent_hole_real+0x67d/0x930 xfs_bmapi_write+0x934/0xc90 xfs_da_grow_inode_int+0x27e/0x2f0 xfs_dir2_grow_inode+0x55/0x130 xfs_dir2_sf_to_block+0x94/0x5d0 xfs_dir2_sf_addname+0xd0/0x590 xfs_dir_createname+0x168/0x1a0 xfs_rename+0x658/0x9b0 By checking that free space records pulled from the trees are within the valid range, we catch many of these corruptions before they can do damage. This is a generic btree record checking deficiency. We need to validate the records we fetch from all the different btrees before we use them to catch corruptions like this. This patch results in a corrupt record emitting an error message and returning -EFSCORRUPTED, and the higher layers catch that and abort: XFS (loop0): Size Freespace BTree record corruption in AG 0 detected! XFS (loop0): start block 0x0 block count 0x0 XFS (loop0): Internal error xfs_trans_cancel at line 1012 of file fs/xfs/xfs_trans.c. Caller xfs_create+0x42a/0x670 ..... Call Trace: dump_stack+0x85/0xcb xfs_trans_cancel+0x19f/0x1c0 xfs_create+0x42a/0x670 xfs_generic_create+0x1f6/0x2c0 vfs_create+0xf9/0x180 do_mknodat+0x1f9/0x210 do_syscall_64+0x5a/0x180 entry_SYSCALL_64_after_hwframe+0x49/0xbe ..... XFS (loop0): xfs_do_force_shutdown(0x8) called from line 1013 of file fs/xfs/xfs_trans.c. Return address = ffffffff81500868 XFS (loop0): Corruption of in-memory data detected. Shutting down filesystem Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-06-06 10:42:13 +08:00
return 0;
out_bad_rec:
xfs_warn(mp,
xfs: Pre-calculate per-AG agbno geometry There is a lot of overhead in functions like xfs_verify_agbno() that repeatedly calculate the geometry limits of an AG. These can be pre-calculated as they are static and the verification context has a per-ag context it can quickly reference. In the case of xfs_verify_agbno(), we now always have a perag context handy, so we can store the AG length and the minimum valid block in the AG in the perag. This means we don't have to calculate it on every call and it can be inlined in callers if we move it to xfs_ag.h. Move xfs_ag_block_count() to xfs_ag.c because it's really a per-ag function and not an XFS type function. We need a little bit of rework that is specific to xfs_initialise_perag() to allow growfs to calculate the new perag sizes before we've updated the primary superblock during the grow (chicken/egg situation). Note that we leave the original xfs_verify_agbno in place in xfs_types.c as a static function as other callers in that file do not have per-ag contexts so still need to go the long way. It's been renamed to xfs_verify_agno_agbno() to indicate it takes both an agno and an agbno to differentiate it from new function. Future commits will make similar changes for other per-ag geometry validation functions. Further: $ size --totals fs/xfs/built-in.a text data bss dec hex filename before 1483006 329588 572 1813166 1baaae (TOTALS) after 1482185 329588 572 1812345 1ba779 (TOTALS) This rework reduces the binary size by ~820 bytes, indicating that much less work is being done to bounds check the agbno values against on per-ag geometry information. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2022-07-07 17:13:02 +08:00
"Refcount BTree record corruption in AG %d detected!",
pag->pag_agno);
xfs: validate btree records on retrieval So we don't check the validity of records as we walk the btree. When there are corrupt records in the free space btree (e.g. zero startblock/length or beyond EOAG) we just blindly use it and things go bad from there. That leads to assert failures on debug kernels like this: XFS: Assertion failed: fs_is_ok, file: fs/xfs/libxfs/xfs_alloc.c, line: 450 .... Call Trace: xfs_alloc_fixup_trees+0x368/0x5c0 xfs_alloc_ag_vextent_near+0x79a/0xe20 xfs_alloc_ag_vextent+0x1d3/0x330 xfs_alloc_vextent+0x5e9/0x870 Or crashes like this: XFS (loop0): xfs_buf_find: daddr 0x7fb28 out of range, EOFS 0x8000 ..... BUG: unable to handle kernel NULL pointer dereference at 00000000000000c8 .... Call Trace: xfs_bmap_add_extent_hole_real+0x67d/0x930 xfs_bmapi_write+0x934/0xc90 xfs_da_grow_inode_int+0x27e/0x2f0 xfs_dir2_grow_inode+0x55/0x130 xfs_dir2_sf_to_block+0x94/0x5d0 xfs_dir2_sf_addname+0xd0/0x590 xfs_dir_createname+0x168/0x1a0 xfs_rename+0x658/0x9b0 By checking that free space records pulled from the trees are within the valid range, we catch many of these corruptions before they can do damage. This is a generic btree record checking deficiency. We need to validate the records we fetch from all the different btrees before we use them to catch corruptions like this. This patch results in a corrupt record emitting an error message and returning -EFSCORRUPTED, and the higher layers catch that and abort: XFS (loop0): Size Freespace BTree record corruption in AG 0 detected! XFS (loop0): start block 0x0 block count 0x0 XFS (loop0): Internal error xfs_trans_cancel at line 1012 of file fs/xfs/xfs_trans.c. Caller xfs_create+0x42a/0x670 ..... Call Trace: dump_stack+0x85/0xcb xfs_trans_cancel+0x19f/0x1c0 xfs_create+0x42a/0x670 xfs_generic_create+0x1f6/0x2c0 vfs_create+0xf9/0x180 do_mknodat+0x1f9/0x210 do_syscall_64+0x5a/0x180 entry_SYSCALL_64_after_hwframe+0x49/0xbe ..... XFS (loop0): xfs_do_force_shutdown(0x8) called from line 1013 of file fs/xfs/xfs_trans.c. Return address = ffffffff81500868 XFS (loop0): Corruption of in-memory data detected. Shutting down filesystem Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-06-06 10:42:13 +08:00
xfs_warn(mp,
"Start block 0x%x, block count 0x%x, references 0x%x",
irec->rc_startblock, irec->rc_blockcount, irec->rc_refcount);
return -EFSCORRUPTED;
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
}
/*
* Update the record referred to by cur to the value given
* by [bno, len, refcount].
* This either works (return 0) or gets an EFSCORRUPTED error.
*/
STATIC int
xfs_refcount_update(
struct xfs_btree_cur *cur,
struct xfs_refcount_irec *irec)
{
union xfs_btree_rec rec;
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
uint32_t start;
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
int error;
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
trace_xfs_refcount_update(cur->bc_mp, cur->bc_ag.pag->pag_agno, irec);
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
start = xfs_refcount_encode_startblock(irec->rc_startblock,
irec->rc_domain);
rec.refc.rc_startblock = cpu_to_be32(start);
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
rec.refc.rc_blockcount = cpu_to_be32(irec->rc_blockcount);
rec.refc.rc_refcount = cpu_to_be32(irec->rc_refcount);
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
error = xfs_btree_update(cur, &rec);
if (error)
trace_xfs_refcount_update_error(cur->bc_mp,
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
cur->bc_ag.pag->pag_agno, error, _RET_IP_);
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
return error;
}
/*
* Insert the record referred to by cur to the value given
* by [bno, len, refcount].
* This either works (return 0) or gets an EFSCORRUPTED error.
*/
xfs: expose various functions to repair code Expose various helpers that the repair code will want to use. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-05-10 01:02:02 +08:00
int
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
xfs_refcount_insert(
struct xfs_btree_cur *cur,
struct xfs_refcount_irec *irec,
int *i)
{
int error;
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
trace_xfs_refcount_insert(cur->bc_mp, cur->bc_ag.pag->pag_agno, irec);
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
cur->bc_rec.rc.rc_startblock = irec->rc_startblock;
cur->bc_rec.rc.rc_blockcount = irec->rc_blockcount;
cur->bc_rec.rc.rc_refcount = irec->rc_refcount;
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
cur->bc_rec.rc.rc_domain = irec->rc_domain;
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
error = xfs_btree_insert(cur, i);
xfs: fix error handling in xfs_refcount_insert() generic/475 fired an assert failure just after the filesystem was shut down: XFS: Assertion failed: fs_is_ok, file: fs/xfs/libxfs/xfs_refcount.c, line: 182 ..... Call Trace: xfs_refcount_insert+0x151/0x190 xfs_refcount_adjust_extents.constprop.11+0x9c/0x470 xfs_refcount_adjust.constprop.10+0xb0/0x270 xfs_refcount_finish_one+0x25a/0x420 xfs_trans_log_finish_refcount_update+0x2a/0x40 xfs_refcount_update_finish_item+0x35/0xa0 xfs_defer_finish+0x15e/0x4d0 xfs_reflink_remap_extent+0x1bc/0x610 xfs_reflink_remap_blocks+0x6e/0x280 xfs_reflink_remap_range+0x311/0x530 vfs_clone_file_range+0x119/0x200 .... If xfs_btree_insert() returns an error, the corruption check fires instead of passing the error back the caller. The corruption check should be after we've checked for an error, not before, thereby avoiding assert failures if the filesystem shuts down during a refcount btree record insert. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-06-01 07:49:00 +08:00
if (error)
goto out_error;
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, *i != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: fix error handling in xfs_refcount_insert() generic/475 fired an assert failure just after the filesystem was shut down: XFS: Assertion failed: fs_is_ok, file: fs/xfs/libxfs/xfs_refcount.c, line: 182 ..... Call Trace: xfs_refcount_insert+0x151/0x190 xfs_refcount_adjust_extents.constprop.11+0x9c/0x470 xfs_refcount_adjust.constprop.10+0xb0/0x270 xfs_refcount_finish_one+0x25a/0x420 xfs_trans_log_finish_refcount_update+0x2a/0x40 xfs_refcount_update_finish_item+0x35/0xa0 xfs_defer_finish+0x15e/0x4d0 xfs_reflink_remap_extent+0x1bc/0x610 xfs_reflink_remap_blocks+0x6e/0x280 xfs_reflink_remap_range+0x311/0x530 vfs_clone_file_range+0x119/0x200 .... If xfs_btree_insert() returns an error, the corruption check fires instead of passing the error back the caller. The corruption check should be after we've checked for an error, not before, thereby avoiding assert failures if the filesystem shuts down during a refcount btree record insert. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-06-01 07:49:00 +08:00
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
out_error:
if (error)
trace_xfs_refcount_insert_error(cur->bc_mp,
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
cur->bc_ag.pag->pag_agno, error, _RET_IP_);
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
return error;
}
/*
* Remove the record referred to by cur, then set the pointer to the spot
* where the record could be re-inserted, in case we want to increment or
* decrement the cursor.
* This either works (return 0) or gets an EFSCORRUPTED error.
*/
STATIC int
xfs_refcount_delete(
struct xfs_btree_cur *cur,
int *i)
{
struct xfs_refcount_irec irec;
int found_rec;
int error;
error = xfs_refcount_get_rec(cur, &irec, &found_rec);
if (error)
goto out_error;
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, found_rec != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
trace_xfs_refcount_delete(cur->bc_mp, cur->bc_ag.pag->pag_agno, &irec);
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
error = xfs_btree_delete(cur, i);
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, *i != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
if (error)
goto out_error;
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
error = xfs_refcount_lookup_ge(cur, irec.rc_domain, irec.rc_startblock,
&found_rec);
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
out_error:
if (error)
trace_xfs_refcount_delete_error(cur->bc_mp,
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
cur->bc_ag.pag->pag_agno, error, _RET_IP_);
xfs: add refcount btree operations Implement the generic btree operations required to manipulate refcount btree blocks. The implementation is similar to the bmapbt, though it will only allocate and free blocks from the AG. Since the refcount root and level fields are separate from the existing roots and levels array, they need a separate logging flag. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: fix logging of AGF refcount btree fields] Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:19 +08:00
return error;
}
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
/*
* Adjusting the Reference Count
*
* As stated elsewhere, the reference count btree (refcbt) stores
* >1 reference counts for extents of physical blocks. In this
* operation, we're either raising or lowering the reference count of
* some subrange stored in the tree:
*
* <------ adjustment range ------>
* ----+ +---+-----+ +--+--------+---------
* 2 | | 3 | 4 | |17| 55 | 10
* ----+ +---+-----+ +--+--------+---------
* X axis is physical blocks number;
* reference counts are the numbers inside the rectangles
*
* The first thing we need to do is to ensure that there are no
* refcount extents crossing either boundary of the range to be
* adjusted. For any extent that does cross a boundary, split it into
* two extents so that we can increment the refcount of one of the
* pieces later:
*
* <------ adjustment range ------>
* ----+ +---+-----+ +--+--------+----+----
* 2 | | 3 | 2 | |17| 55 | 10 | 10
* ----+ +---+-----+ +--+--------+----+----
*
* For this next step, let's assume that all the physical blocks in
* the adjustment range are mapped to a file and are therefore in use
* at least once. Therefore, we can infer that any gap in the
* refcount tree within the adjustment range represents a physical
* extent with refcount == 1:
*
* <------ adjustment range ------>
* ----+---+---+-----+-+--+--------+----+----
* 2 |"1"| 3 | 2 |1|17| 55 | 10 | 10
* ----+---+---+-----+-+--+--------+----+----
* ^
*
* For each extent that falls within the interval range, figure out
* which extent is to the left or the right of that extent. Now we
* have a left, current, and right extent. If the new reference count
* of the center extent enables us to merge left, center, and right
* into one record covering all three, do so. If the center extent is
* at the left end of the range, abuts the left extent, and its new
* reference count matches the left extent's record, then merge them.
* If the center extent is at the right end of the range, abuts the
* right extent, and the reference counts match, merge those. In the
* example, we can left merge (assuming an increment operation):
*
* <------ adjustment range ------>
* --------+---+-----+-+--+--------+----+----
* 2 | 3 | 2 |1|17| 55 | 10 | 10
* --------+---+-----+-+--+--------+----+----
* ^
*
* For all other extents within the range, adjust the reference count
* or delete it if the refcount falls below 2. If we were
* incrementing, the end result looks like this:
*
* <------ adjustment range ------>
* --------+---+-----+-+--+--------+----+----
* 2 | 4 | 3 |2|18| 56 | 11 | 10
* --------+---+-----+-+--+--------+----+----
*
* The result of a decrement operation looks as such:
*
* <------ adjustment range ------>
* ----+ +---+ +--+--------+----+----
* 2 | | 2 | |16| 54 | 9 | 10
* ----+ +---+ +--+--------+----+----
* DDDD 111111DD
*
* The blocks marked "D" are freed; the blocks marked "1" are only
* referenced once and therefore the record is removed from the
* refcount btree.
*/
/* Next block after this extent. */
static inline xfs_agblock_t
xfs_refc_next(
struct xfs_refcount_irec *rc)
{
return rc->rc_startblock + rc->rc_blockcount;
}
/*
* Split a refcount extent that crosses agbno.
*/
STATIC int
xfs_refcount_split_extent(
struct xfs_btree_cur *cur,
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
enum xfs_refc_domain domain,
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
xfs_agblock_t agbno,
bool *shape_changed)
{
struct xfs_refcount_irec rcext, tmp;
int found_rec;
int error;
*shape_changed = false;
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
error = xfs_refcount_lookup_le(cur, domain, agbno, &found_rec);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
if (error)
goto out_error;
if (!found_rec)
return 0;
error = xfs_refcount_get_rec(cur, &rcext, &found_rec);
if (error)
goto out_error;
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, found_rec != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
if (rcext.rc_startblock == agbno || xfs_refc_next(&rcext) <= agbno)
return 0;
*shape_changed = true;
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
trace_xfs_refcount_split_extent(cur->bc_mp, cur->bc_ag.pag->pag_agno,
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
&rcext, agbno);
/* Establish the right extent. */
tmp = rcext;
tmp.rc_startblock = agbno;
tmp.rc_blockcount -= (agbno - rcext.rc_startblock);
error = xfs_refcount_update(cur, &tmp);
if (error)
goto out_error;
/* Insert the left extent. */
tmp = rcext;
tmp.rc_blockcount = agbno - rcext.rc_startblock;
error = xfs_refcount_insert(cur, &tmp, &found_rec);
if (error)
goto out_error;
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, found_rec != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
return error;
out_error:
trace_xfs_refcount_split_extent_error(cur->bc_mp,
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
cur->bc_ag.pag->pag_agno, error, _RET_IP_);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
return error;
}
/*
* Merge the left, center, and right extents.
*/
STATIC int
xfs_refcount_merge_center_extents(
struct xfs_btree_cur *cur,
struct xfs_refcount_irec *left,
struct xfs_refcount_irec *center,
struct xfs_refcount_irec *right,
unsigned long long extlen,
xfs_extlen_t *aglen)
{
int error;
int found_rec;
trace_xfs_refcount_merge_center_extents(cur->bc_mp,
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
cur->bc_ag.pag->pag_agno, left, center, right);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
/*
* Make sure the center and right extents are not in the btree.
* If the center extent was synthesized, the first delete call
* removes the right extent and we skip the second deletion.
* If center and right were in the btree, then the first delete
* call removes the center and the second one removes the right
* extent.
*/
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
error = xfs_refcount_lookup_ge(cur, center->rc_domain,
center->rc_startblock, &found_rec);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
if (error)
goto out_error;
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, found_rec != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
error = xfs_refcount_delete(cur, &found_rec);
if (error)
goto out_error;
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, found_rec != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
if (center->rc_refcount > 1) {
error = xfs_refcount_delete(cur, &found_rec);
if (error)
goto out_error;
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, found_rec != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
}
/* Enlarge the left extent. */
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
error = xfs_refcount_lookup_le(cur, left->rc_domain,
left->rc_startblock, &found_rec);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
if (error)
goto out_error;
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, found_rec != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
left->rc_blockcount = extlen;
error = xfs_refcount_update(cur, left);
if (error)
goto out_error;
*aglen = 0;
return error;
out_error:
trace_xfs_refcount_merge_center_extents_error(cur->bc_mp,
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
cur->bc_ag.pag->pag_agno, error, _RET_IP_);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
return error;
}
/*
* Merge with the left extent.
*/
STATIC int
xfs_refcount_merge_left_extent(
struct xfs_btree_cur *cur,
struct xfs_refcount_irec *left,
struct xfs_refcount_irec *cleft,
xfs_agblock_t *agbno,
xfs_extlen_t *aglen)
{
int error;
int found_rec;
trace_xfs_refcount_merge_left_extent(cur->bc_mp,
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
cur->bc_ag.pag->pag_agno, left, cleft);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
/* If the extent at agbno (cleft) wasn't synthesized, remove it. */
if (cleft->rc_refcount > 1) {
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
error = xfs_refcount_lookup_le(cur, cleft->rc_domain,
cleft->rc_startblock, &found_rec);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
if (error)
goto out_error;
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, found_rec != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
error = xfs_refcount_delete(cur, &found_rec);
if (error)
goto out_error;
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, found_rec != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
}
/* Enlarge the left extent. */
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
error = xfs_refcount_lookup_le(cur, left->rc_domain,
left->rc_startblock, &found_rec);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
if (error)
goto out_error;
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, found_rec != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
left->rc_blockcount += cleft->rc_blockcount;
error = xfs_refcount_update(cur, left);
if (error)
goto out_error;
*agbno += cleft->rc_blockcount;
*aglen -= cleft->rc_blockcount;
return error;
out_error:
trace_xfs_refcount_merge_left_extent_error(cur->bc_mp,
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
cur->bc_ag.pag->pag_agno, error, _RET_IP_);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
return error;
}
/*
* Merge with the right extent.
*/
STATIC int
xfs_refcount_merge_right_extent(
struct xfs_btree_cur *cur,
struct xfs_refcount_irec *right,
struct xfs_refcount_irec *cright,
xfs_extlen_t *aglen)
{
int error;
int found_rec;
trace_xfs_refcount_merge_right_extent(cur->bc_mp,
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
cur->bc_ag.pag->pag_agno, cright, right);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
/*
* If the extent ending at agbno+aglen (cright) wasn't synthesized,
* remove it.
*/
if (cright->rc_refcount > 1) {
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
error = xfs_refcount_lookup_le(cur, cright->rc_domain,
cright->rc_startblock, &found_rec);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
if (error)
goto out_error;
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, found_rec != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
error = xfs_refcount_delete(cur, &found_rec);
if (error)
goto out_error;
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, found_rec != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
}
/* Enlarge the right extent. */
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
error = xfs_refcount_lookup_le(cur, right->rc_domain,
right->rc_startblock, &found_rec);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
if (error)
goto out_error;
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, found_rec != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
right->rc_startblock -= cright->rc_blockcount;
right->rc_blockcount += cright->rc_blockcount;
error = xfs_refcount_update(cur, right);
if (error)
goto out_error;
*aglen -= cright->rc_blockcount;
return error;
out_error:
trace_xfs_refcount_merge_right_extent_error(cur->bc_mp,
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
cur->bc_ag.pag->pag_agno, error, _RET_IP_);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
return error;
}
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
#define XFS_FIND_RCEXT_SHARED 1
#define XFS_FIND_RCEXT_COW 2
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
/*
* Find the left extent and the one after it (cleft). This function assumes
* that we've already split any extent crossing agbno.
*/
STATIC int
xfs_refcount_find_left_extents(
struct xfs_btree_cur *cur,
struct xfs_refcount_irec *left,
struct xfs_refcount_irec *cleft,
xfs_agblock_t agbno,
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
xfs_extlen_t aglen,
int flags)
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
{
struct xfs_refcount_irec tmp;
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
enum xfs_refc_domain domain;
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
int error;
int found_rec;
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
if (flags & XFS_FIND_RCEXT_SHARED)
domain = XFS_REFC_DOMAIN_SHARED;
else
domain = XFS_REFC_DOMAIN_COW;
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
left->rc_startblock = cleft->rc_startblock = NULLAGBLOCK;
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
error = xfs_refcount_lookup_le(cur, domain, agbno - 1, &found_rec);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
if (error)
goto out_error;
if (!found_rec)
return 0;
error = xfs_refcount_get_rec(cur, &tmp, &found_rec);
if (error)
goto out_error;
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, found_rec != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
if (xfs_refc_next(&tmp) != agbno)
return 0;
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
if ((flags & XFS_FIND_RCEXT_SHARED) && tmp.rc_refcount < 2)
return 0;
if ((flags & XFS_FIND_RCEXT_COW) && tmp.rc_refcount > 1)
return 0;
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
/* We have a left extent; retrieve (or invent) the next right one */
*left = tmp;
error = xfs_btree_increment(cur, 0, &found_rec);
if (error)
goto out_error;
if (found_rec) {
error = xfs_refcount_get_rec(cur, &tmp, &found_rec);
if (error)
goto out_error;
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, found_rec != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
/* if tmp starts at the end of our range, just use that */
if (tmp.rc_startblock == agbno)
*cleft = tmp;
else {
/*
* There's a gap in the refcntbt at the start of the
* range we're interested in (refcount == 1) so
* synthesize the implied extent and pass it back.
* We assume here that the agbno/aglen range was
* passed in from a data fork extent mapping and
* therefore is allocated to exactly one owner.
*/
cleft->rc_startblock = agbno;
cleft->rc_blockcount = min(aglen,
tmp.rc_startblock - agbno);
cleft->rc_refcount = 1;
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
cleft->rc_domain = domain;
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
}
} else {
/*
* No extents, so pretend that there's one covering the whole
* range.
*/
cleft->rc_startblock = agbno;
cleft->rc_blockcount = aglen;
cleft->rc_refcount = 1;
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
cleft->rc_domain = domain;
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
}
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
trace_xfs_refcount_find_left_extent(cur->bc_mp, cur->bc_ag.pag->pag_agno,
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
left, cleft, agbno);
return error;
out_error:
trace_xfs_refcount_find_left_extent_error(cur->bc_mp,
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
cur->bc_ag.pag->pag_agno, error, _RET_IP_);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
return error;
}
/*
* Find the right extent and the one before it (cright). This function
* assumes that we've already split any extents crossing agbno + aglen.
*/
STATIC int
xfs_refcount_find_right_extents(
struct xfs_btree_cur *cur,
struct xfs_refcount_irec *right,
struct xfs_refcount_irec *cright,
xfs_agblock_t agbno,
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
xfs_extlen_t aglen,
int flags)
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
{
struct xfs_refcount_irec tmp;
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
enum xfs_refc_domain domain;
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
int error;
int found_rec;
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
if (flags & XFS_FIND_RCEXT_SHARED)
domain = XFS_REFC_DOMAIN_SHARED;
else
domain = XFS_REFC_DOMAIN_COW;
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
right->rc_startblock = cright->rc_startblock = NULLAGBLOCK;
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
error = xfs_refcount_lookup_ge(cur, domain, agbno + aglen, &found_rec);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
if (error)
goto out_error;
if (!found_rec)
return 0;
error = xfs_refcount_get_rec(cur, &tmp, &found_rec);
if (error)
goto out_error;
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, found_rec != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
if (tmp.rc_startblock != agbno + aglen)
return 0;
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
if ((flags & XFS_FIND_RCEXT_SHARED) && tmp.rc_refcount < 2)
return 0;
if ((flags & XFS_FIND_RCEXT_COW) && tmp.rc_refcount > 1)
return 0;
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
/* We have a right extent; retrieve (or invent) the next left one */
*right = tmp;
error = xfs_btree_decrement(cur, 0, &found_rec);
if (error)
goto out_error;
if (found_rec) {
error = xfs_refcount_get_rec(cur, &tmp, &found_rec);
if (error)
goto out_error;
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, found_rec != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
/* if tmp ends at the end of our range, just use that */
if (xfs_refc_next(&tmp) == agbno + aglen)
*cright = tmp;
else {
/*
* There's a gap in the refcntbt at the end of the
* range we're interested in (refcount == 1) so
* create the implied extent and pass it back.
* We assume here that the agbno/aglen range was
* passed in from a data fork extent mapping and
* therefore is allocated to exactly one owner.
*/
cright->rc_startblock = max(agbno, xfs_refc_next(&tmp));
cright->rc_blockcount = right->rc_startblock -
cright->rc_startblock;
cright->rc_refcount = 1;
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
cright->rc_domain = domain;
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
}
} else {
/*
* No extents, so pretend that there's one covering the whole
* range.
*/
cright->rc_startblock = agbno;
cright->rc_blockcount = aglen;
cright->rc_refcount = 1;
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
cright->rc_domain = domain;
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
}
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
trace_xfs_refcount_find_right_extent(cur->bc_mp, cur->bc_ag.pag->pag_agno,
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
cright, right, agbno + aglen);
return error;
out_error:
trace_xfs_refcount_find_right_extent_error(cur->bc_mp,
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
cur->bc_ag.pag->pag_agno, error, _RET_IP_);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
return error;
}
/* Is this extent valid? */
static inline bool
xfs_refc_valid(
struct xfs_refcount_irec *rc)
{
return rc->rc_startblock != NULLAGBLOCK;
}
/*
* Try to merge with any extents on the boundaries of the adjustment range.
*/
STATIC int
xfs_refcount_merge_extents(
struct xfs_btree_cur *cur,
xfs_agblock_t *agbno,
xfs_extlen_t *aglen,
enum xfs_refc_adjust_op adjust,
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
int flags,
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
bool *shape_changed)
{
struct xfs_refcount_irec left = {0}, cleft = {0};
struct xfs_refcount_irec cright = {0}, right = {0};
int error;
unsigned long long ulen;
bool cequal;
*shape_changed = false;
/*
* Find the extent just below agbno [left], just above agbno [cleft],
* just below (agbno + aglen) [cright], and just above (agbno + aglen)
* [right].
*/
error = xfs_refcount_find_left_extents(cur, &left, &cleft, *agbno,
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
*aglen, flags);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
if (error)
return error;
error = xfs_refcount_find_right_extents(cur, &right, &cright, *agbno,
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
*aglen, flags);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
if (error)
return error;
/* No left or right extent to merge; exit. */
if (!xfs_refc_valid(&left) && !xfs_refc_valid(&right))
return 0;
cequal = (cleft.rc_startblock == cright.rc_startblock) &&
(cleft.rc_blockcount == cright.rc_blockcount);
/* Try to merge left, cleft, and right. cleft must == cright. */
ulen = (unsigned long long)left.rc_blockcount + cleft.rc_blockcount +
right.rc_blockcount;
if (xfs_refc_valid(&left) && xfs_refc_valid(&right) &&
xfs_refc_valid(&cleft) && xfs_refc_valid(&cright) && cequal &&
left.rc_refcount == cleft.rc_refcount + adjust &&
right.rc_refcount == cleft.rc_refcount + adjust &&
ulen < MAXREFCEXTLEN) {
*shape_changed = true;
return xfs_refcount_merge_center_extents(cur, &left, &cleft,
xfs: non-scrub - remove unused function parameters Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-04-07 01:09:42 +08:00
&right, ulen, aglen);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
}
/* Try to merge left and cleft. */
ulen = (unsigned long long)left.rc_blockcount + cleft.rc_blockcount;
if (xfs_refc_valid(&left) && xfs_refc_valid(&cleft) &&
left.rc_refcount == cleft.rc_refcount + adjust &&
ulen < MAXREFCEXTLEN) {
*shape_changed = true;
error = xfs_refcount_merge_left_extent(cur, &left, &cleft,
agbno, aglen);
if (error)
return error;
/*
* If we just merged left + cleft and cleft == cright,
* we no longer have a cright to merge with right. We're done.
*/
if (cequal)
return 0;
}
/* Try to merge cright and right. */
ulen = (unsigned long long)right.rc_blockcount + cright.rc_blockcount;
if (xfs_refc_valid(&right) && xfs_refc_valid(&cright) &&
right.rc_refcount == cright.rc_refcount + adjust &&
ulen < MAXREFCEXTLEN) {
*shape_changed = true;
return xfs_refcount_merge_right_extent(cur, &right, &cright,
xfs: non-scrub - remove unused function parameters Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-04-07 01:09:42 +08:00
aglen);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
}
return error;
}
/*
* XXX: This is a pretty hand-wavy estimate. The penalty for guessing
* true incorrectly is a shutdown FS; the penalty for guessing false
* incorrectly is more transaction rolls than might be necessary.
* Be conservative here.
*/
static bool
xfs_refcount_still_have_space(
struct xfs_btree_cur *cur)
{
unsigned long overhead;
xfs: reduce transaction reservations with reflink Before to the introduction of deferred refcount operations, reflink would try to cram refcount btree updates into the same transaction as an allocation or a free event. Mainline XFS has never actually done that, but we never refactored the transaction reservations to reflect that we now do all refcount updates in separate transactions. Fix this to reduce the transaction reservation size even farther, so that between this patch and the previous one, we reduce the tr_write and tr_itruncate sizes by 66%. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2022-04-26 09:38:14 +08:00
/*
* Worst case estimate: full splits of the free space and rmap btrees
* to handle each of the shape changes to the refcount btree.
*/
xfs: rename xfs_*alloc*_log_count to _block_count These functions return the maximum number of blocks that could be logged in a particular transaction. "log count" is confusing since there's a separate concept of a log (operation) count in the reservation code, so let's change it to "block count" to be less confusing. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2022-04-26 09:38:24 +08:00
overhead = xfs_allocfree_block_count(cur->bc_mp,
xfs: reduce transaction reservations with reflink Before to the introduction of deferred refcount operations, reflink would try to cram refcount btree updates into the same transaction as an allocation or a free event. Mainline XFS has never actually done that, but we never refactored the transaction reservations to reflect that we now do all refcount updates in separate transactions. Fix this to reduce the transaction reservation size even farther, so that between this patch and the previous one, we reduce the tr_write and tr_itruncate sizes by 66%. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2022-04-26 09:38:14 +08:00
cur->bc_ag.refc.shape_changes);
overhead += cur->bc_mp->m_refc_maxlevels;
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
overhead *= cur->bc_mp->m_sb.sb_blocksize;
/*
* Only allow 2 refcount extent updates per transaction if the
* refcount continue update "error" has been injected.
*/
xfs: make the btree ag cursor private union anonymous This is much less widely used than the bc_private union was, so this is done as a single patch. The named union xfs_btree_cur_private goes away and is embedded into the struct xfs_btree_cur_ag as an anonymous union, and the code is modified via this script: $ sed -i 's/priv\.\([abt|refc]\)/\1/g' fs/xfs/*[ch] fs/xfs/*/*[ch] Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-03-11 08:57:51 +08:00
if (cur->bc_ag.refc.nr_ops > 2 &&
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
XFS_TEST_ERROR(false, cur->bc_mp,
xfs: remove unneeded parameter from XFS_TEST_ERROR Since we moved the injected error frequency controls to the mountpoint, we can get rid of the last argument to XFS_TEST_ERROR. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
2017-06-21 08:54:47 +08:00
XFS_ERRTAG_REFCOUNT_CONTINUE_UPDATE))
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
return false;
xfs: make the btree ag cursor private union anonymous This is much less widely used than the bc_private union was, so this is done as a single patch. The named union xfs_btree_cur_private goes away and is embedded into the struct xfs_btree_cur_ag as an anonymous union, and the code is modified via this script: $ sed -i 's/priv\.\([abt|refc]\)/\1/g' fs/xfs/*[ch] fs/xfs/*/*[ch] Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-03-11 08:57:51 +08:00
if (cur->bc_ag.refc.nr_ops == 0)
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
return true;
else if (overhead > cur->bc_tp->t_log_res)
return false;
return cur->bc_tp->t_log_res - overhead >
xfs: make the btree ag cursor private union anonymous This is much less widely used than the bc_private union was, so this is done as a single patch. The named union xfs_btree_cur_private goes away and is embedded into the struct xfs_btree_cur_ag as an anonymous union, and the code is modified via this script: $ sed -i 's/priv\.\([abt|refc]\)/\1/g' fs/xfs/*[ch] fs/xfs/*/*[ch] Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-03-11 08:57:51 +08:00
cur->bc_ag.refc.nr_ops * XFS_REFCOUNT_ITEM_OVERHEAD;
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
}
/*
* Adjust the refcounts of middle extents. At this point we should have
* split extents that crossed the adjustment range; merged with adjacent
* extents; and updated agbno/aglen to reflect the merges. Therefore,
* all we have to do is update the extents inside [agbno, agbno + aglen].
*/
STATIC int
xfs_refcount_adjust_extents(
struct xfs_btree_cur *cur,
xfs_agblock_t *agbno,
xfs_extlen_t *aglen,
xfs: remove unused parameter from refcount code The owner info parameter is always NULL, so get rid of the parameter. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
2021-10-13 06:58:11 +08:00
enum xfs_refc_adjust_op adj)
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
{
struct xfs_refcount_irec ext, tmp;
int error;
int found_rec, found_tmp;
xfs_fsblock_t fsbno;
/* Merging did all the work already. */
if (*aglen == 0)
return 0;
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
error = xfs_refcount_lookup_ge(cur, XFS_REFC_DOMAIN_SHARED, *agbno,
&found_rec);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
if (error)
goto out_error;
while (*aglen > 0 && xfs_refcount_still_have_space(cur)) {
error = xfs_refcount_get_rec(cur, &ext, &found_rec);
if (error)
goto out_error;
if (!found_rec) {
ext.rc_startblock = cur->bc_mp->m_sb.sb_agblocks;
ext.rc_blockcount = 0;
ext.rc_refcount = 0;
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
ext.rc_domain = XFS_REFC_DOMAIN_SHARED;
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
}
/*
* Deal with a hole in the refcount tree; if a file maps to
* these blocks and there's no refcountbt record, pretend that
* there is one with refcount == 1.
*/
if (ext.rc_startblock != *agbno) {
tmp.rc_startblock = *agbno;
tmp.rc_blockcount = min(*aglen,
ext.rc_startblock - *agbno);
tmp.rc_refcount = 1 + adj;
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
tmp.rc_domain = XFS_REFC_DOMAIN_SHARED;
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
trace_xfs_refcount_modify_extent(cur->bc_mp,
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
cur->bc_ag.pag->pag_agno, &tmp);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
/*
* Either cover the hole (increment) or
* delete the range (decrement).
*/
xfs: count EFIs when deciding to ask for a continuation of a refcount update A long time ago, I added to XFS the ability to use deferred reference count operations as part of a transaction chain. This enabled us to avoid blowing out the transaction reservation when the blocks in a physical extent all had different reference counts because we could ask the deferred operation manager for a continuation, which would get us a clean transaction. The refcount code asks for a continuation when the number of refcount record updates reaches the point where we think that the transaction has logged enough full btree blocks due to refcount (and free space) btree shape changes and refcount record updates that we're in danger of overflowing the transaction. We did not previously count the EFIs logged to the refcount update transaction because the clamps on the length of a bunmap operation were sufficient to avoid overflowing the transaction reservation even in the worst case situation where every other block of the unmapped extent is shared. Unfortunately, the restrictions on bunmap length avoid failure in the worst case by imposing a maximum unmap length of ~3000 blocks, even for non-pathological cases. This seriously limits performance when freeing large extents. Therefore, track EFIs with the same counter as refcount record updates, and use that information as input into when we should ask for a continuation. This enables the next patch to drop the clumsy bunmap limitation. Depends: 27dada070d59 ("xfs: change the order in which child and parent defer ops ar finished") Depends: 74f4d6a1e065 ("xfs: only relog deferred intent items if free space in the log gets low") Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2022-04-27 06:29:54 +08:00
cur->bc_ag.refc.nr_ops++;
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
if (tmp.rc_refcount) {
error = xfs_refcount_insert(cur, &tmp,
&found_tmp);
if (error)
goto out_error;
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp,
found_tmp != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
} else {
fsbno = XFS_AGB_TO_FSB(cur->bc_mp,
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
cur->bc_ag.pag->pag_agno,
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
tmp.rc_startblock);
xfs: rename xfs_bmap_add_free to xfs_free_extent_later xfs_bmap_add_free isn't a block mapping function; it schedules deferred freeing operations for a later point in a compound transaction chain. While it's primarily used by bunmapi, its use has expanded beyond that. Move it to xfs_alloc.c and rename the function since it's now general freeing functionality. Bring the slab cache bits in line with the way we handle the other intent items. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
2021-10-13 05:17:01 +08:00
xfs_free_extent_later(cur->bc_tp, fsbno,
xfs: remove unused parameter from refcount code The owner info parameter is always NULL, so get rid of the parameter. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
2021-10-13 06:58:11 +08:00
tmp.rc_blockcount, NULL);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
}
(*agbno) += tmp.rc_blockcount;
(*aglen) -= tmp.rc_blockcount;
xfs: make sure aglen never goes negative in xfs_refcount_adjust_extents Prior to calling xfs_refcount_adjust_extents, we trimmed agbno/aglen such that the end of the range would not be in the middle of a refcount record. If this is no longer the case, something is seriously wrong with the btree. Bail out with a corruption error. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-26 09:18:21 +08:00
/* Stop if there's nothing left to modify */
if (*aglen == 0 || !xfs_refcount_still_have_space(cur))
break;
/* Move the cursor to the start of ext. */
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
error = xfs_refcount_lookup_ge(cur,
XFS_REFC_DOMAIN_SHARED, *agbno,
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
&found_rec);
if (error)
goto out_error;
}
xfs: make sure aglen never goes negative in xfs_refcount_adjust_extents Prior to calling xfs_refcount_adjust_extents, we trimmed agbno/aglen such that the end of the range would not be in the middle of a refcount record. If this is no longer the case, something is seriously wrong with the btree. Bail out with a corruption error. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-26 09:18:21 +08:00
/*
* A previous step trimmed agbno/aglen such that the end of the
* range would not be in the middle of the record. If this is
* no longer the case, something is seriously wrong with the
* btree. Make sure we never feed the synthesized record into
* the processing loop below.
*/
if (XFS_IS_CORRUPT(cur->bc_mp, ext.rc_blockcount == 0) ||
XFS_IS_CORRUPT(cur->bc_mp, ext.rc_blockcount > *aglen)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
/*
* Adjust the reference count and either update the tree
* (incr) or free the blocks (decr).
*/
if (ext.rc_refcount == MAXREFCOUNT)
goto skip;
ext.rc_refcount += adj;
trace_xfs_refcount_modify_extent(cur->bc_mp,
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
cur->bc_ag.pag->pag_agno, &ext);
xfs: count EFIs when deciding to ask for a continuation of a refcount update A long time ago, I added to XFS the ability to use deferred reference count operations as part of a transaction chain. This enabled us to avoid blowing out the transaction reservation when the blocks in a physical extent all had different reference counts because we could ask the deferred operation manager for a continuation, which would get us a clean transaction. The refcount code asks for a continuation when the number of refcount record updates reaches the point where we think that the transaction has logged enough full btree blocks due to refcount (and free space) btree shape changes and refcount record updates that we're in danger of overflowing the transaction. We did not previously count the EFIs logged to the refcount update transaction because the clamps on the length of a bunmap operation were sufficient to avoid overflowing the transaction reservation even in the worst case situation where every other block of the unmapped extent is shared. Unfortunately, the restrictions on bunmap length avoid failure in the worst case by imposing a maximum unmap length of ~3000 blocks, even for non-pathological cases. This seriously limits performance when freeing large extents. Therefore, track EFIs with the same counter as refcount record updates, and use that information as input into when we should ask for a continuation. This enables the next patch to drop the clumsy bunmap limitation. Depends: 27dada070d59 ("xfs: change the order in which child and parent defer ops ar finished") Depends: 74f4d6a1e065 ("xfs: only relog deferred intent items if free space in the log gets low") Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2022-04-27 06:29:54 +08:00
cur->bc_ag.refc.nr_ops++;
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
if (ext.rc_refcount > 1) {
error = xfs_refcount_update(cur, &ext);
if (error)
goto out_error;
} else if (ext.rc_refcount == 1) {
error = xfs_refcount_delete(cur, &found_rec);
if (error)
goto out_error;
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, found_rec != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
goto advloop;
} else {
fsbno = XFS_AGB_TO_FSB(cur->bc_mp,
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
cur->bc_ag.pag->pag_agno,
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
ext.rc_startblock);
xfs: remove unused parameter from refcount code The owner info parameter is always NULL, so get rid of the parameter. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
2021-10-13 06:58:11 +08:00
xfs_free_extent_later(cur->bc_tp, fsbno,
ext.rc_blockcount, NULL);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
}
skip:
error = xfs_btree_increment(cur, 0, &found_rec);
if (error)
goto out_error;
advloop:
(*agbno) += ext.rc_blockcount;
(*aglen) -= ext.rc_blockcount;
}
return error;
out_error:
trace_xfs_refcount_modify_extent_error(cur->bc_mp,
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
cur->bc_ag.pag->pag_agno, error, _RET_IP_);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
return error;
}
/* Adjust the reference count of a range of AG blocks. */
STATIC int
xfs_refcount_adjust(
struct xfs_btree_cur *cur,
xfs_agblock_t agbno,
xfs_extlen_t aglen,
xfs_agblock_t *new_agbno,
xfs_extlen_t *new_aglen,
xfs: remove unused parameter from refcount code The owner info parameter is always NULL, so get rid of the parameter. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
2021-10-13 06:58:11 +08:00
enum xfs_refc_adjust_op adj)
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
{
bool shape_changed;
int shape_changes = 0;
int error;
*new_agbno = agbno;
*new_aglen = aglen;
if (adj == XFS_REFCOUNT_ADJUST_INCREASE)
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
trace_xfs_refcount_increase(cur->bc_mp, cur->bc_ag.pag->pag_agno,
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
agbno, aglen);
else
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
trace_xfs_refcount_decrease(cur->bc_mp, cur->bc_ag.pag->pag_agno,
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
agbno, aglen);
/*
* Ensure that no rcextents cross the boundary of the adjustment range.
*/
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
error = xfs_refcount_split_extent(cur, XFS_REFC_DOMAIN_SHARED,
agbno, &shape_changed);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
if (error)
goto out_error;
if (shape_changed)
shape_changes++;
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
error = xfs_refcount_split_extent(cur, XFS_REFC_DOMAIN_SHARED,
agbno + aglen, &shape_changed);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
if (error)
goto out_error;
if (shape_changed)
shape_changes++;
/*
* Try to merge with the left or right extents of the range.
*/
error = xfs_refcount_merge_extents(cur, new_agbno, new_aglen, adj,
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
XFS_FIND_RCEXT_SHARED, &shape_changed);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
if (error)
goto out_error;
if (shape_changed)
shape_changes++;
if (shape_changes)
xfs: make the btree ag cursor private union anonymous This is much less widely used than the bc_private union was, so this is done as a single patch. The named union xfs_btree_cur_private goes away and is embedded into the struct xfs_btree_cur_ag as an anonymous union, and the code is modified via this script: $ sed -i 's/priv\.\([abt|refc]\)/\1/g' fs/xfs/*[ch] fs/xfs/*/*[ch] Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-03-11 08:57:51 +08:00
cur->bc_ag.refc.shape_changes++;
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
/* Now that we've taken care of the ends, adjust the middle extents */
xfs: remove unused parameter from refcount code The owner info parameter is always NULL, so get rid of the parameter. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
2021-10-13 06:58:11 +08:00
error = xfs_refcount_adjust_extents(cur, new_agbno, new_aglen, adj);
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
if (error)
goto out_error;
return 0;
out_error:
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
trace_xfs_refcount_adjust_error(cur->bc_mp, cur->bc_ag.pag->pag_agno,
xfs: adjust refcount of an extent of blocks in refcount btree Provide functions to adjust the reference counts for an extent of physical blocks stored in the refcount btree. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:21 +08:00
error, _RET_IP_);
return error;
}
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
/* Clean up after calling xfs_refcount_finish_one. */
void
xfs_refcount_finish_one_cleanup(
struct xfs_trans *tp,
struct xfs_btree_cur *rcur,
int error)
{
struct xfs_buf *agbp;
if (rcur == NULL)
return;
xfs: convert btree cursor ag-private member name bc_private.a -> bc_ag conversion via script: `sed -i 's/bc_private\.a/bc_ag/g' fs/xfs/*[ch] fs/xfs/*/*[ch]` And then revert the change to the bc_ag #define in fs/xfs/libxfs/xfs_btree.h manually. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-03-11 08:51:15 +08:00
agbp = rcur->bc_ag.agbp;
xfs: trivial xfs_btree_del_cursor cleanups The error argument to xfs_btree_del_cursor already understands the "nonzero for error" semantics, so remove pointless error testing in the callers and pass it directly. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2018-07-20 03:26:31 +08:00
xfs_btree_del_cursor(rcur, error);
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
if (error)
xfs_trans_brelse(tp, agbp);
}
xfs: check deferred refcount op continuation parameters If we're in the middle of a deferred refcount operation and decide to roll the transaction to avoid overflowing the transaction space, we need to check the new agbno/aglen parameters that we're about to record in the new intent. Specifically, we need to check that the new extent is completely within the filesystem, and that continuation does not put us into a different AG. If the keys of a node block are wrong, the lookup to resume an xfs_refcount_adjust_extents operation can put us into the wrong record block. If this happens, we might not find that we run out of aglen at an exact record boundary, which will cause the loop control to do the wrong thing. The previous patch should take care of that problem, but let's add this extra sanity check to stop corruption problems sooner than later. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 02:33:47 +08:00
/*
* Set up a continuation a deferred refcount operation by updating the intent.
* Checks to make sure we're not going to run off the end of the AG.
*/
static inline int
xfs_refcount_continue_op(
struct xfs_btree_cur *cur,
xfs_fsblock_t startblock,
xfs_agblock_t new_agbno,
xfs_extlen_t new_len,
xfs_fsblock_t *new_fsbno)
{
struct xfs_mount *mp = cur->bc_mp;
struct xfs_perag *pag = cur->bc_ag.pag;
if (XFS_IS_CORRUPT(mp, !xfs_verify_agbext(pag, new_agbno, new_len)))
return -EFSCORRUPTED;
*new_fsbno = XFS_AGB_TO_FSB(mp, pag->pag_agno, new_agbno);
ASSERT(xfs_verify_fsbext(mp, *new_fsbno, new_len));
ASSERT(pag->pag_agno == XFS_FSB_TO_AGNO(mp, *new_fsbno));
return 0;
}
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
/*
* Process one of the deferred refcount operations. We pass back the
* btree cursor to maintain our lock on the btree between calls.
* This saves time and eliminates a buffer deadlock between the
* superblock and the AGF because we'll always grab them in the same
* order.
*/
int
xfs_refcount_finish_one(
struct xfs_trans *tp,
enum xfs_refcount_intent_type type,
xfs_fsblock_t startblock,
xfs_extlen_t blockcount,
xfs_fsblock_t *new_fsb,
xfs_extlen_t *new_len,
struct xfs_btree_cur **pcur)
{
struct xfs_mount *mp = tp->t_mountp;
struct xfs_btree_cur *rcur;
struct xfs_buf *agbp = NULL;
int error = 0;
xfs_agblock_t bno;
xfs_agblock_t new_agbno;
unsigned long nr_ops = 0;
int shape_changes = 0;
xfs: convert refcount btree cursor to use perags Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
struct xfs_perag *pag;
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
xfs: convert refcount btree cursor to use perags Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
pag = xfs_perag_get(mp, XFS_FSB_TO_AGNO(mp, startblock));
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
bno = XFS_FSB_TO_AGBNO(mp, startblock);
trace_xfs_refcount_deferred(mp, XFS_FSB_TO_AGNO(mp, startblock),
type, XFS_FSB_TO_AGBNO(mp, startblock),
blockcount);
xfs: convert refcount btree cursor to use perags Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
if (XFS_TEST_ERROR(false, mp, XFS_ERRTAG_REFCOUNT_FINISH_ONE)) {
error = -EIO;
goto out_drop;
}
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
/*
* If we haven't gotten a cursor or the cursor AG doesn't match
* the startblock, get one now.
*/
rcur = *pcur;
xfs: convert refcount btree cursor to use perags Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
if (rcur != NULL && rcur->bc_ag.pag != pag) {
xfs: make the btree ag cursor private union anonymous This is much less widely used than the bc_private union was, so this is done as a single patch. The named union xfs_btree_cur_private goes away and is embedded into the struct xfs_btree_cur_ag as an anonymous union, and the code is modified via this script: $ sed -i 's/priv\.\([abt|refc]\)/\1/g' fs/xfs/*[ch] fs/xfs/*/*[ch] Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-03-11 08:57:51 +08:00
nr_ops = rcur->bc_ag.refc.nr_ops;
shape_changes = rcur->bc_ag.refc.shape_changes;
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
xfs_refcount_finish_one_cleanup(tp, rcur, 0);
rcur = NULL;
*pcur = NULL;
}
if (rcur == NULL) {
xfs: pass perag to xfs_alloc_read_agf() xfs_alloc_read_agf() initialises the perag if it hasn't been done yet, so it makes sense to pass it the perag rather than pull a reference from the buffer. This allows callers to be per-ag centric rather than passing mount/agno pairs everywhere. Whilst modifying the xfs_reflink_find_shared() function definition, declare it static and remove the extern declaration as it is an internal function only these days. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2022-07-07 17:07:40 +08:00
error = xfs_alloc_read_agf(pag, tp, XFS_ALLOC_FLAG_FREEING,
&agbp);
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
if (error)
xfs: convert refcount btree cursor to use perags Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
goto out_drop;
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
xfs: convert refcount btree cursor to use perags Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
rcur = xfs_refcountbt_init_cursor(mp, tp, agbp, pag);
xfs: make the btree ag cursor private union anonymous This is much less widely used than the bc_private union was, so this is done as a single patch. The named union xfs_btree_cur_private goes away and is embedded into the struct xfs_btree_cur_ag as an anonymous union, and the code is modified via this script: $ sed -i 's/priv\.\([abt|refc]\)/\1/g' fs/xfs/*[ch] fs/xfs/*/*[ch] Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-03-11 08:57:51 +08:00
rcur->bc_ag.refc.nr_ops = nr_ops;
rcur->bc_ag.refc.shape_changes = shape_changes;
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
}
*pcur = rcur;
switch (type) {
case XFS_REFCOUNT_INCREASE:
error = xfs_refcount_adjust(rcur, bno, blockcount, &new_agbno,
xfs: remove unused parameter from refcount code The owner info parameter is always NULL, so get rid of the parameter. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
2021-10-13 06:58:11 +08:00
new_len, XFS_REFCOUNT_ADJUST_INCREASE);
xfs: check deferred refcount op continuation parameters If we're in the middle of a deferred refcount operation and decide to roll the transaction to avoid overflowing the transaction space, we need to check the new agbno/aglen parameters that we're about to record in the new intent. Specifically, we need to check that the new extent is completely within the filesystem, and that continuation does not put us into a different AG. If the keys of a node block are wrong, the lookup to resume an xfs_refcount_adjust_extents operation can put us into the wrong record block. If this happens, we might not find that we run out of aglen at an exact record boundary, which will cause the loop control to do the wrong thing. The previous patch should take care of that problem, but let's add this extra sanity check to stop corruption problems sooner than later. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 02:33:47 +08:00
if (error)
goto out_drop;
if (*new_len > 0)
error = xfs_refcount_continue_op(rcur, startblock,
new_agbno, *new_len, new_fsb);
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
break;
case XFS_REFCOUNT_DECREASE:
error = xfs_refcount_adjust(rcur, bno, blockcount, &new_agbno,
xfs: remove unused parameter from refcount code The owner info parameter is always NULL, so get rid of the parameter. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
2021-10-13 06:58:11 +08:00
new_len, XFS_REFCOUNT_ADJUST_DECREASE);
xfs: check deferred refcount op continuation parameters If we're in the middle of a deferred refcount operation and decide to roll the transaction to avoid overflowing the transaction space, we need to check the new agbno/aglen parameters that we're about to record in the new intent. Specifically, we need to check that the new extent is completely within the filesystem, and that continuation does not put us into a different AG. If the keys of a node block are wrong, the lookup to resume an xfs_refcount_adjust_extents operation can put us into the wrong record block. If this happens, we might not find that we run out of aglen at an exact record boundary, which will cause the loop control to do the wrong thing. The previous patch should take care of that problem, but let's add this extra sanity check to stop corruption problems sooner than later. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 02:33:47 +08:00
if (error)
goto out_drop;
if (*new_len > 0)
error = xfs_refcount_continue_op(rcur, startblock,
new_agbno, *new_len, new_fsb);
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
break;
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
case XFS_REFCOUNT_ALLOC_COW:
*new_fsb = startblock + blockcount;
*new_len = 0;
xfs: pass transaction to xfs_defer_add() The majority of remaining references to struct xfs_defer_ops in XFS are associated with xfs_defer_add(). At this point, there are no more external xfs_defer_ops users left. All instances of xfs_defer_ops are embedded in the transaction, which means we can safely pass the transaction down to the dfops add interface. Update xfs_defer_add() to receive the transaction as a parameter. Various subsystems implement wrappers to allocate and construct the context specific data structures for the associated deferred operation type. Update these to also carry the transaction down as needed and clean up unused dfops parameters along the way. This removes most of the remaining references to struct xfs_defer_ops throughout the code and facilitates removal of the structure. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> [darrick: fix unused variable warnings with ftrace disabled] Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-08-01 22:20:34 +08:00
error = __xfs_refcount_cow_alloc(rcur, bno, blockcount);
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
break;
case XFS_REFCOUNT_FREE_COW:
*new_fsb = startblock + blockcount;
*new_len = 0;
xfs: pass transaction to xfs_defer_add() The majority of remaining references to struct xfs_defer_ops in XFS are associated with xfs_defer_add(). At this point, there are no more external xfs_defer_ops users left. All instances of xfs_defer_ops are embedded in the transaction, which means we can safely pass the transaction down to the dfops add interface. Update xfs_defer_add() to receive the transaction as a parameter. Various subsystems implement wrappers to allocate and construct the context specific data structures for the associated deferred operation type. Update these to also carry the transaction down as needed and clean up unused dfops parameters along the way. This removes most of the remaining references to struct xfs_defer_ops throughout the code and facilitates removal of the structure. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> [darrick: fix unused variable warnings with ftrace disabled] Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-08-01 22:20:34 +08:00
error = __xfs_refcount_cow_free(rcur, bno, blockcount);
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
break;
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
default:
ASSERT(0);
error = -EFSCORRUPTED;
}
if (!error && *new_len > 0)
xfs: convert refcount btree cursor to use perags Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
trace_xfs_refcount_finish_one_leftover(mp, pag->pag_agno, type,
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
bno, blockcount, new_agbno, *new_len);
xfs: convert refcount btree cursor to use perags Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
out_drop:
xfs_perag_put(pag);
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
return error;
}
/*
* Record a refcount intent for later processing.
*/
xfs: remove unnecessary int returns from deferred refcount functions Remove the return value from the functions that schedule deferred refcount operations since they never fail and do not return status. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2019-08-27 08:06:04 +08:00
static void
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
__xfs_refcount_add(
xfs: pass transaction to xfs_defer_add() The majority of remaining references to struct xfs_defer_ops in XFS are associated with xfs_defer_add(). At this point, there are no more external xfs_defer_ops users left. All instances of xfs_defer_ops are embedded in the transaction, which means we can safely pass the transaction down to the dfops add interface. Update xfs_defer_add() to receive the transaction as a parameter. Various subsystems implement wrappers to allocate and construct the context specific data structures for the associated deferred operation type. Update these to also carry the transaction down as needed and clean up unused dfops parameters along the way. This removes most of the remaining references to struct xfs_defer_ops throughout the code and facilitates removal of the structure. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> [darrick: fix unused variable warnings with ftrace disabled] Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-08-01 22:20:34 +08:00
struct xfs_trans *tp,
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
enum xfs_refcount_intent_type type,
xfs_fsblock_t startblock,
xfs_extlen_t blockcount)
{
struct xfs_refcount_intent *ri;
xfs: pass transaction to xfs_defer_add() The majority of remaining references to struct xfs_defer_ops in XFS are associated with xfs_defer_add(). At this point, there are no more external xfs_defer_ops users left. All instances of xfs_defer_ops are embedded in the transaction, which means we can safely pass the transaction down to the dfops add interface. Update xfs_defer_add() to receive the transaction as a parameter. Various subsystems implement wrappers to allocate and construct the context specific data structures for the associated deferred operation type. Update these to also carry the transaction down as needed and clean up unused dfops parameters along the way. This removes most of the remaining references to struct xfs_defer_ops throughout the code and facilitates removal of the structure. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> [darrick: fix unused variable warnings with ftrace disabled] Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-08-01 22:20:34 +08:00
trace_xfs_refcount_defer(tp->t_mountp,
XFS_FSB_TO_AGNO(tp->t_mountp, startblock),
type, XFS_FSB_TO_AGBNO(tp->t_mountp, startblock),
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
blockcount);
xfs: create slab caches for frequently-used deferred items Create slab caches for the high-level structures that coordinate deferred intent items, since they're used fairly heavily. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
2021-10-13 05:11:01 +08:00
ri = kmem_cache_alloc(xfs_refcount_intent_cache,
GFP_NOFS | __GFP_NOFAIL);
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
INIT_LIST_HEAD(&ri->ri_list);
ri->ri_type = type;
ri->ri_startblock = startblock;
ri->ri_blockcount = blockcount;
xfs: pass transaction to xfs_defer_add() The majority of remaining references to struct xfs_defer_ops in XFS are associated with xfs_defer_add(). At this point, there are no more external xfs_defer_ops users left. All instances of xfs_defer_ops are embedded in the transaction, which means we can safely pass the transaction down to the dfops add interface. Update xfs_defer_add() to receive the transaction as a parameter. Various subsystems implement wrappers to allocate and construct the context specific data structures for the associated deferred operation type. Update these to also carry the transaction down as needed and clean up unused dfops parameters along the way. This removes most of the remaining references to struct xfs_defer_ops throughout the code and facilitates removal of the structure. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> [darrick: fix unused variable warnings with ftrace disabled] Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-08-01 22:20:34 +08:00
xfs_defer_add(tp, XFS_DEFER_OPS_TYPE_REFCOUNT, &ri->ri_list);
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
}
/*
* Increase the reference count of the blocks backing a file's extent.
*/
xfs: remove unnecessary int returns from deferred refcount functions Remove the return value from the functions that schedule deferred refcount operations since they never fail and do not return status. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2019-08-27 08:06:04 +08:00
void
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
xfs_refcount_increase_extent(
xfs: pass transaction to xfs_defer_add() The majority of remaining references to struct xfs_defer_ops in XFS are associated with xfs_defer_add(). At this point, there are no more external xfs_defer_ops users left. All instances of xfs_defer_ops are embedded in the transaction, which means we can safely pass the transaction down to the dfops add interface. Update xfs_defer_add() to receive the transaction as a parameter. Various subsystems implement wrappers to allocate and construct the context specific data structures for the associated deferred operation type. Update these to also carry the transaction down as needed and clean up unused dfops parameters along the way. This removes most of the remaining references to struct xfs_defer_ops throughout the code and facilitates removal of the structure. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> [darrick: fix unused variable warnings with ftrace disabled] Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-08-01 22:20:34 +08:00
struct xfs_trans *tp,
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
struct xfs_bmbt_irec *PREV)
{
xfs: convert xfs_sb_version_has checks to use mount features This is a conversion of the remaining xfs_sb_version_has..(sbp) checks to use xfs_has_..(mp) feature checks. This was largely done with a vim replacement macro that did: :0,$s/xfs_sb_version_has\(.*\)&\(.*\)->m_sb/xfs_has_\1\2/g<CR> A couple of other variants were also used, and the rest touched up by hand. $ size -t fs/xfs/built-in.a text data bss dec hex filename before 1127533 311352 484 1439369 15f689 (TOTALS) after 1125360 311352 484 1437196 15ee0c (TOTALS) Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-08-19 09:46:55 +08:00
if (!xfs_has_reflink(tp->t_mountp))
xfs: remove unnecessary int returns from deferred refcount functions Remove the return value from the functions that schedule deferred refcount operations since they never fail and do not return status. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2019-08-27 08:06:04 +08:00
return;
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
xfs: remove unnecessary int returns from deferred refcount functions Remove the return value from the functions that schedule deferred refcount operations since they never fail and do not return status. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2019-08-27 08:06:04 +08:00
__xfs_refcount_add(tp, XFS_REFCOUNT_INCREASE, PREV->br_startblock,
PREV->br_blockcount);
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
}
/*
* Decrease the reference count of the blocks backing a file's extent.
*/
xfs: remove unnecessary int returns from deferred refcount functions Remove the return value from the functions that schedule deferred refcount operations since they never fail and do not return status. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2019-08-27 08:06:04 +08:00
void
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
xfs_refcount_decrease_extent(
xfs: pass transaction to xfs_defer_add() The majority of remaining references to struct xfs_defer_ops in XFS are associated with xfs_defer_add(). At this point, there are no more external xfs_defer_ops users left. All instances of xfs_defer_ops are embedded in the transaction, which means we can safely pass the transaction down to the dfops add interface. Update xfs_defer_add() to receive the transaction as a parameter. Various subsystems implement wrappers to allocate and construct the context specific data structures for the associated deferred operation type. Update these to also carry the transaction down as needed and clean up unused dfops parameters along the way. This removes most of the remaining references to struct xfs_defer_ops throughout the code and facilitates removal of the structure. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> [darrick: fix unused variable warnings with ftrace disabled] Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-08-01 22:20:34 +08:00
struct xfs_trans *tp,
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
struct xfs_bmbt_irec *PREV)
{
xfs: convert xfs_sb_version_has checks to use mount features This is a conversion of the remaining xfs_sb_version_has..(sbp) checks to use xfs_has_..(mp) feature checks. This was largely done with a vim replacement macro that did: :0,$s/xfs_sb_version_has\(.*\)&\(.*\)->m_sb/xfs_has_\1\2/g<CR> A couple of other variants were also used, and the rest touched up by hand. $ size -t fs/xfs/built-in.a text data bss dec hex filename before 1127533 311352 484 1439369 15f689 (TOTALS) after 1125360 311352 484 1437196 15ee0c (TOTALS) Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-08-19 09:46:55 +08:00
if (!xfs_has_reflink(tp->t_mountp))
xfs: remove unnecessary int returns from deferred refcount functions Remove the return value from the functions that schedule deferred refcount operations since they never fail and do not return status. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2019-08-27 08:06:04 +08:00
return;
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
xfs: remove unnecessary int returns from deferred refcount functions Remove the return value from the functions that schedule deferred refcount operations since they never fail and do not return status. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2019-08-27 08:06:04 +08:00
__xfs_refcount_add(tp, XFS_REFCOUNT_DECREASE, PREV->br_startblock,
PREV->br_blockcount);
xfs: connect refcount adjust functions to upper layers Plumb in the upper level interface to schedule and finish deferred refcount operations via the deferred ops mechanism. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:22 +08:00
}
xfs: introduce reflink utility functions These functions will be used by the other reflink functions to find the maximum length of a range of shared blocks. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.coM> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:25 +08:00
/*
* Given an AG extent, find the lowest-numbered run of shared blocks
* within that range and return the range in fbno/flen. If
* find_end_of_shared is set, return the longest contiguous extent of
* shared blocks; if not, just return the first extent we find. If no
* shared blocks are found, fbno and flen will be set to NULLAGBLOCK
* and 0, respectively.
*/
int
xfs_refcount_find_shared(
struct xfs_btree_cur *cur,
xfs_agblock_t agbno,
xfs_extlen_t aglen,
xfs_agblock_t *fbno,
xfs_extlen_t *flen,
bool find_end_of_shared)
{
struct xfs_refcount_irec tmp;
int i;
int have;
int error;
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
trace_xfs_refcount_find_shared(cur->bc_mp, cur->bc_ag.pag->pag_agno,
xfs: introduce reflink utility functions These functions will be used by the other reflink functions to find the maximum length of a range of shared blocks. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.coM> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:25 +08:00
agbno, aglen);
/* By default, skip the whole range */
*fbno = NULLAGBLOCK;
*flen = 0;
/* Try to find a refcount extent that crosses the start */
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
error = xfs_refcount_lookup_le(cur, XFS_REFC_DOMAIN_SHARED, agbno,
&have);
xfs: introduce reflink utility functions These functions will be used by the other reflink functions to find the maximum length of a range of shared blocks. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.coM> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:25 +08:00
if (error)
goto out_error;
if (!have) {
/* No left extent, look at the next one */
error = xfs_btree_increment(cur, 0, &have);
if (error)
goto out_error;
if (!have)
goto done;
}
error = xfs_refcount_get_rec(cur, &tmp, &i);
if (error)
goto out_error;
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, i != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: introduce reflink utility functions These functions will be used by the other reflink functions to find the maximum length of a range of shared blocks. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.coM> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:25 +08:00
/* If the extent ends before the start, look at the next one */
if (tmp.rc_startblock + tmp.rc_blockcount <= agbno) {
error = xfs_btree_increment(cur, 0, &have);
if (error)
goto out_error;
if (!have)
goto done;
error = xfs_refcount_get_rec(cur, &tmp, &i);
if (error)
goto out_error;
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, i != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: introduce reflink utility functions These functions will be used by the other reflink functions to find the maximum length of a range of shared blocks. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.coM> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:25 +08:00
}
/* If the extent starts after the range we want, bail out */
if (tmp.rc_startblock >= agbno + aglen)
goto done;
/* We found the start of a shared extent! */
if (tmp.rc_startblock < agbno) {
tmp.rc_blockcount -= (agbno - tmp.rc_startblock);
tmp.rc_startblock = agbno;
}
*fbno = tmp.rc_startblock;
*flen = min(tmp.rc_blockcount, agbno + aglen - *fbno);
if (!find_end_of_shared)
goto done;
/* Otherwise, find the end of this shared extent */
while (*fbno + *flen < agbno + aglen) {
error = xfs_btree_increment(cur, 0, &have);
if (error)
goto out_error;
if (!have)
break;
error = xfs_refcount_get_rec(cur, &tmp, &i);
if (error)
goto out_error;
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, i != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: introduce reflink utility functions These functions will be used by the other reflink functions to find the maximum length of a range of shared blocks. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.coM> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:25 +08:00
if (tmp.rc_startblock >= agbno + aglen ||
tmp.rc_startblock != *fbno + *flen)
break;
*flen = min(*flen + tmp.rc_blockcount, agbno + aglen - *fbno);
}
done:
trace_xfs_refcount_find_shared_result(cur->bc_mp,
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
cur->bc_ag.pag->pag_agno, *fbno, *flen);
xfs: introduce reflink utility functions These functions will be used by the other reflink functions to find the maximum length of a range of shared blocks. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.coM> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:25 +08:00
out_error:
if (error)
trace_xfs_refcount_find_shared_error(cur->bc_mp,
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
cur->bc_ag.pag->pag_agno, error, _RET_IP_);
xfs: introduce reflink utility functions These functions will be used by the other reflink functions to find the maximum length of a range of shared blocks. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.coM> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:25 +08:00
return error;
}
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
/*
* Recovering CoW Blocks After a Crash
*
* Due to the way that the copy on write mechanism works, there's a window of
* opportunity in which we can lose track of allocated blocks during a crash.
* Because CoW uses delayed allocation in the in-core CoW fork, writeback
* causes blocks to be allocated and stored in the CoW fork. The blocks are
* no longer in the free space btree but are not otherwise recorded anywhere
* until the write completes and the blocks are mapped into the file. A crash
* in between allocation and remapping results in the replacement blocks being
* lost. This situation is exacerbated by the CoW extent size hint because
* allocations can hang around for long time.
*
* However, there is a place where we can record these allocations before they
* become mappings -- the reference count btree. The btree does not record
* extents with refcount == 1, so we can record allocations with a refcount of
* 1. Blocks being used for CoW writeout cannot be shared, so there should be
* no conflict with shared block records. These mappings should be created
* when we allocate blocks to the CoW fork and deleted when they're removed
* from the CoW fork.
*
* Minor nit: records for in-progress CoW allocations and records for shared
* extents must never be merged, to preserve the property that (except for CoW
* allocations) there are no refcount btree entries with refcount == 1. The
* only time this could potentially happen is when unsharing a block that's
* adjacent to CoW allocations, so we must be careful to avoid this.
*
* At mount time we recover lost CoW allocations by searching the refcount
* btree for these refcount == 1 mappings. These represent CoW allocations
* that were in progress at the time the filesystem went down, so we can free
* them to get the space back.
*
* This mechanism is superior to creating EFIs for unmapped CoW extents for
* several reasons -- first, EFIs pin the tail of the log and would have to be
* periodically relogged to avoid filling up the log. Second, CoW completions
* will have to file an EFD and create new EFIs for whatever remains in the
* CoW fork; this partially takes care of (1) but extent-size reservations
* will have to periodically relog even if there's no writeout in progress.
* This can happen if the CoW extent size hint is set, which you really want.
* Third, EFIs cannot currently be automatically relogged into newer
* transactions to advance the log tail. Fourth, stuffing the log full of
* EFIs places an upper bound on the number of CoW allocations that can be
* held filesystem-wide at any given time. Recording them in the refcount
* btree doesn't require us to maintain any state in memory and doesn't pin
* the log.
*/
/*
* Adjust the refcounts of CoW allocations. These allocations are "magic"
* in that they're not referenced anywhere else in the filesystem, so we
* stash them in the refcount btree with a refcount of 1 until either file
* remapping (or CoW cancellation) happens.
*/
STATIC int
xfs_refcount_adjust_cow_extents(
struct xfs_btree_cur *cur,
xfs_agblock_t agbno,
xfs_extlen_t aglen,
xfs: non-scrub - remove unused function parameters Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-04-07 01:09:42 +08:00
enum xfs_refc_adjust_op adj)
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
{
struct xfs_refcount_irec ext, tmp;
int error;
int found_rec, found_tmp;
if (aglen == 0)
return 0;
/* Find any overlapping refcount records */
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
error = xfs_refcount_lookup_ge(cur, XFS_REFC_DOMAIN_COW, agbno,
&found_rec);
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
if (error)
goto out_error;
error = xfs_refcount_get_rec(cur, &ext, &found_rec);
if (error)
goto out_error;
if (!found_rec) {
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
ext.rc_startblock = cur->bc_mp->m_sb.sb_agblocks;
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
ext.rc_blockcount = 0;
ext.rc_refcount = 0;
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
ext.rc_domain = XFS_REFC_DOMAIN_COW;
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
}
switch (adj) {
case XFS_REFCOUNT_ADJUST_COW_ALLOC:
/* Adding a CoW reservation, there should be nothing here. */
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp,
agbno + aglen > ext.rc_startblock)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
tmp.rc_startblock = agbno;
tmp.rc_blockcount = aglen;
tmp.rc_refcount = 1;
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
tmp.rc_domain = XFS_REFC_DOMAIN_COW;
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
trace_xfs_refcount_modify_extent(cur->bc_mp,
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
cur->bc_ag.pag->pag_agno, &tmp);
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
error = xfs_refcount_insert(cur, &tmp,
&found_tmp);
if (error)
goto out_error;
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, found_tmp != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
break;
case XFS_REFCOUNT_ADJUST_COW_FREE:
/* Removing a CoW reservation, there should be one extent. */
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, ext.rc_startblock != agbno)) {
error = -EFSCORRUPTED;
goto out_error;
}
if (XFS_IS_CORRUPT(cur->bc_mp, ext.rc_blockcount != aglen)) {
error = -EFSCORRUPTED;
goto out_error;
}
if (XFS_IS_CORRUPT(cur->bc_mp, ext.rc_refcount != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
ext.rc_refcount = 0;
trace_xfs_refcount_modify_extent(cur->bc_mp,
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
cur->bc_ag.pag->pag_agno, &ext);
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
error = xfs_refcount_delete(cur, &found_rec);
if (error)
goto out_error;
xfs: kill the XFS_WANT_CORRUPT_* macros The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the creation of local variables and redirections of the code flow. This is pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that remove both of those ugly points. The change was performed with the following coccinelle script: @@ expression mp, test; identifier label; @@ - XFS_WANT_CORRUPTED_GOTO(mp, test, label); + if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; } @@ expression mp, test; @@ - XFS_WANT_CORRUPTED_RETURN(mp, test); + if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED; @@ expression mp, lval, rval; @@ - XFS_IS_CORRUPT(mp, !(lval == rval)) + XFS_IS_CORRUPT(mp, lval != rval) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 && e2)) + XFS_IS_CORRUPT(mp, !e1 || !e2) @@ expression e1, e2; @@ - !(e1 == e2) + e1 != e2 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 && e3 == e4) || e5 != e6 + e1 != e2 || e3 != e4 || e5 != e6 @@ expression e1, e2, e3, e4, e5, e6; @@ - !(e1 == e2 || (e3 <= e4 && e5 <= e6)) + e1 != e2 && (e3 > e4 || e5 > e6) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2)) + XFS_IS_CORRUPT(mp, e1 > e2) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 < e2)) + XFS_IS_CORRUPT(mp, e1 >= e2) @@ expression mp, e1; @@ - XFS_IS_CORRUPT(mp, !!e1) + XFS_IS_CORRUPT(mp, e1) @@ expression mp, e1, e2; @@ - XFS_IS_CORRUPT(mp, !(e1 || e2)) + XFS_IS_CORRUPT(mp, !e1 && !e2) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4)) + XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4) @@ expression mp, e1, e2, e3, e4; @@ - XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4)) + XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:52:18 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp, found_rec != 1)) {
error = -EFSCORRUPTED;
goto out_error;
}
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
break;
default:
ASSERT(0);
}
return error;
out_error:
trace_xfs_refcount_modify_extent_error(cur->bc_mp,
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
cur->bc_ag.pag->pag_agno, error, _RET_IP_);
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
return error;
}
/*
* Add or remove refcount btree entries for CoW reservations.
*/
STATIC int
xfs_refcount_adjust_cow(
struct xfs_btree_cur *cur,
xfs_agblock_t agbno,
xfs_extlen_t aglen,
xfs: non-scrub - remove unused function parameters Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-04-07 01:09:42 +08:00
enum xfs_refc_adjust_op adj)
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
{
bool shape_changed;
int error;
/*
* Ensure that no rcextents cross the boundary of the adjustment range.
*/
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
error = xfs_refcount_split_extent(cur, XFS_REFC_DOMAIN_COW,
agbno, &shape_changed);
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
if (error)
goto out_error;
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
error = xfs_refcount_split_extent(cur, XFS_REFC_DOMAIN_COW,
agbno + aglen, &shape_changed);
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
if (error)
goto out_error;
/*
* Try to merge with the left or right extents of the range.
*/
error = xfs_refcount_merge_extents(cur, &agbno, &aglen, adj,
XFS_FIND_RCEXT_COW, &shape_changed);
if (error)
goto out_error;
/* Now that we've taken care of the ends, adjust the middle extents */
xfs: non-scrub - remove unused function parameters Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-04-07 01:09:42 +08:00
error = xfs_refcount_adjust_cow_extents(cur, agbno, aglen, adj);
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
if (error)
goto out_error;
return 0;
out_error:
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
trace_xfs_refcount_adjust_cow_error(cur->bc_mp, cur->bc_ag.pag->pag_agno,
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
error, _RET_IP_);
return error;
}
/*
* Record a CoW allocation in the refcount btree.
*/
STATIC int
__xfs_refcount_cow_alloc(
struct xfs_btree_cur *rcur,
xfs_agblock_t agbno,
xfs: pass transaction to xfs_defer_add() The majority of remaining references to struct xfs_defer_ops in XFS are associated with xfs_defer_add(). At this point, there are no more external xfs_defer_ops users left. All instances of xfs_defer_ops are embedded in the transaction, which means we can safely pass the transaction down to the dfops add interface. Update xfs_defer_add() to receive the transaction as a parameter. Various subsystems implement wrappers to allocate and construct the context specific data structures for the associated deferred operation type. Update these to also carry the transaction down as needed and clean up unused dfops parameters along the way. This removes most of the remaining references to struct xfs_defer_ops throughout the code and facilitates removal of the structure. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> [darrick: fix unused variable warnings with ftrace disabled] Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-08-01 22:20:34 +08:00
xfs_extlen_t aglen)
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
{
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
trace_xfs_refcount_cow_increase(rcur->bc_mp, rcur->bc_ag.pag->pag_agno,
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
agbno, aglen);
/* Add refcount btree reservation */
xfs: queue deferred rmap ops for cow staging extent alloc/free in the right order Under the deferred rmap operation scheme, there's a certain order in which the rmap deferred ops have to be queued to maintain integrity during log replay. For alloc/map operations that order is cui -> rui; for free/unmap operations that order is cui -> rui -> efi. However, the initial refcount code got the ordering wrong in the free side of things because it queued refcount free op and an EFI and the refcount free op queued a rmap free op, resulting in the order cui -> efi -> rui. If we fail before the efd finishes, the efi recovery will try to do a wildcard rmap removal and the subsequent rui will fail to find the rmap and blow up. This didn't ever happen due to other screws up in handling unknown owner rmap removals, but those other screw ups broke recovery in other ways, so fix the ordering to follow the intended rules. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-12-08 11:07:03 +08:00
return xfs_refcount_adjust_cow(rcur, agbno, aglen,
xfs: non-scrub - remove unused function parameters Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-04-07 01:09:42 +08:00
XFS_REFCOUNT_ADJUST_COW_ALLOC);
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
}
/*
* Remove a CoW allocation from the refcount btree.
*/
STATIC int
__xfs_refcount_cow_free(
struct xfs_btree_cur *rcur,
xfs_agblock_t agbno,
xfs: pass transaction to xfs_defer_add() The majority of remaining references to struct xfs_defer_ops in XFS are associated with xfs_defer_add(). At this point, there are no more external xfs_defer_ops users left. All instances of xfs_defer_ops are embedded in the transaction, which means we can safely pass the transaction down to the dfops add interface. Update xfs_defer_add() to receive the transaction as a parameter. Various subsystems implement wrappers to allocate and construct the context specific data structures for the associated deferred operation type. Update these to also carry the transaction down as needed and clean up unused dfops parameters along the way. This removes most of the remaining references to struct xfs_defer_ops throughout the code and facilitates removal of the structure. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> [darrick: fix unused variable warnings with ftrace disabled] Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-08-01 22:20:34 +08:00
xfs_extlen_t aglen)
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
{
xfs: remove agno from btree cursor Now that everything passes a perag, the agno is not needed anymore. Convert all the users to use pag->pag_agno instead and remove the agno from the cursor. This was largely done as an automated search and replace. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
trace_xfs_refcount_cow_decrease(rcur->bc_mp, rcur->bc_ag.pag->pag_agno,
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
agbno, aglen);
/* Remove refcount btree reservation */
xfs: queue deferred rmap ops for cow staging extent alloc/free in the right order Under the deferred rmap operation scheme, there's a certain order in which the rmap deferred ops have to be queued to maintain integrity during log replay. For alloc/map operations that order is cui -> rui; for free/unmap operations that order is cui -> rui -> efi. However, the initial refcount code got the ordering wrong in the free side of things because it queued refcount free op and an EFI and the refcount free op queued a rmap free op, resulting in the order cui -> efi -> rui. If we fail before the efd finishes, the efi recovery will try to do a wildcard rmap removal and the subsequent rui will fail to find the rmap and blow up. This didn't ever happen due to other screws up in handling unknown owner rmap removals, but those other screw ups broke recovery in other ways, so fix the ordering to follow the intended rules. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-12-08 11:07:03 +08:00
return xfs_refcount_adjust_cow(rcur, agbno, aglen,
xfs: non-scrub - remove unused function parameters Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-04-07 01:09:42 +08:00
XFS_REFCOUNT_ADJUST_COW_FREE);
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
}
/* Record a CoW staging extent in the refcount btree. */
xfs: remove unnecessary int returns from deferred refcount functions Remove the return value from the functions that schedule deferred refcount operations since they never fail and do not return status. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2019-08-27 08:06:04 +08:00
void
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
xfs_refcount_alloc_cow_extent(
xfs: pass transaction to xfs_defer_add() The majority of remaining references to struct xfs_defer_ops in XFS are associated with xfs_defer_add(). At this point, there are no more external xfs_defer_ops users left. All instances of xfs_defer_ops are embedded in the transaction, which means we can safely pass the transaction down to the dfops add interface. Update xfs_defer_add() to receive the transaction as a parameter. Various subsystems implement wrappers to allocate and construct the context specific data structures for the associated deferred operation type. Update these to also carry the transaction down as needed and clean up unused dfops parameters along the way. This removes most of the remaining references to struct xfs_defer_ops throughout the code and facilitates removal of the structure. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> [darrick: fix unused variable warnings with ftrace disabled] Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-08-01 22:20:34 +08:00
struct xfs_trans *tp,
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
xfs_fsblock_t fsb,
xfs_extlen_t len)
{
xfs: pass transaction to xfs_defer_add() The majority of remaining references to struct xfs_defer_ops in XFS are associated with xfs_defer_add(). At this point, there are no more external xfs_defer_ops users left. All instances of xfs_defer_ops are embedded in the transaction, which means we can safely pass the transaction down to the dfops add interface. Update xfs_defer_add() to receive the transaction as a parameter. Various subsystems implement wrappers to allocate and construct the context specific data structures for the associated deferred operation type. Update these to also carry the transaction down as needed and clean up unused dfops parameters along the way. This removes most of the remaining references to struct xfs_defer_ops throughout the code and facilitates removal of the structure. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> [darrick: fix unused variable warnings with ftrace disabled] Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-08-01 22:20:34 +08:00
struct xfs_mount *mp = tp->t_mountp;
xfs: queue deferred rmap ops for cow staging extent alloc/free in the right order Under the deferred rmap operation scheme, there's a certain order in which the rmap deferred ops have to be queued to maintain integrity during log replay. For alloc/map operations that order is cui -> rui; for free/unmap operations that order is cui -> rui -> efi. However, the initial refcount code got the ordering wrong in the free side of things because it queued refcount free op and an EFI and the refcount free op queued a rmap free op, resulting in the order cui -> efi -> rui. If we fail before the efd finishes, the efi recovery will try to do a wildcard rmap removal and the subsequent rui will fail to find the rmap and blow up. This didn't ever happen due to other screws up in handling unknown owner rmap removals, but those other screw ups broke recovery in other ways, so fix the ordering to follow the intended rules. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-12-08 11:07:03 +08:00
xfs: convert xfs_sb_version_has checks to use mount features This is a conversion of the remaining xfs_sb_version_has..(sbp) checks to use xfs_has_..(mp) feature checks. This was largely done with a vim replacement macro that did: :0,$s/xfs_sb_version_has\(.*\)&\(.*\)->m_sb/xfs_has_\1\2/g<CR> A couple of other variants were also used, and the rest touched up by hand. $ size -t fs/xfs/built-in.a text data bss dec hex filename before 1127533 311352 484 1439369 15f689 (TOTALS) after 1125360 311352 484 1437196 15ee0c (TOTALS) Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-08-19 09:46:55 +08:00
if (!xfs_has_reflink(mp))
xfs: remove unnecessary int returns from deferred refcount functions Remove the return value from the functions that schedule deferred refcount operations since they never fail and do not return status. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2019-08-27 08:06:04 +08:00
return;
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
xfs: remove unnecessary int returns from deferred refcount functions Remove the return value from the functions that schedule deferred refcount operations since they never fail and do not return status. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2019-08-27 08:06:04 +08:00
__xfs_refcount_add(tp, XFS_REFCOUNT_ALLOC_COW, fsb, len);
xfs: queue deferred rmap ops for cow staging extent alloc/free in the right order Under the deferred rmap operation scheme, there's a certain order in which the rmap deferred ops have to be queued to maintain integrity during log replay. For alloc/map operations that order is cui -> rui; for free/unmap operations that order is cui -> rui -> efi. However, the initial refcount code got the ordering wrong in the free side of things because it queued refcount free op and an EFI and the refcount free op queued a rmap free op, resulting in the order cui -> efi -> rui. If we fail before the efd finishes, the efi recovery will try to do a wildcard rmap removal and the subsequent rui will fail to find the rmap and blow up. This didn't ever happen due to other screws up in handling unknown owner rmap removals, but those other screw ups broke recovery in other ways, so fix the ordering to follow the intended rules. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-12-08 11:07:03 +08:00
/* Add rmap entry */
xfs: remove unnecessary int returns from deferred rmap functions Remove the return value from the functions that schedule deferred rmap operations since they never fail and do not return status. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2019-08-27 08:06:03 +08:00
xfs_rmap_alloc_extent(tp, XFS_FSB_TO_AGNO(mp, fsb),
xfs: queue deferred rmap ops for cow staging extent alloc/free in the right order Under the deferred rmap operation scheme, there's a certain order in which the rmap deferred ops have to be queued to maintain integrity during log replay. For alloc/map operations that order is cui -> rui; for free/unmap operations that order is cui -> rui -> efi. However, the initial refcount code got the ordering wrong in the free side of things because it queued refcount free op and an EFI and the refcount free op queued a rmap free op, resulting in the order cui -> efi -> rui. If we fail before the efd finishes, the efi recovery will try to do a wildcard rmap removal and the subsequent rui will fail to find the rmap and blow up. This didn't ever happen due to other screws up in handling unknown owner rmap removals, but those other screw ups broke recovery in other ways, so fix the ordering to follow the intended rules. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-12-08 11:07:03 +08:00
XFS_FSB_TO_AGBNO(mp, fsb), len, XFS_RMAP_OWN_COW);
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
}
/* Forget a CoW staging event in the refcount btree. */
xfs: remove unnecessary int returns from deferred refcount functions Remove the return value from the functions that schedule deferred refcount operations since they never fail and do not return status. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2019-08-27 08:06:04 +08:00
void
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
xfs_refcount_free_cow_extent(
xfs: pass transaction to xfs_defer_add() The majority of remaining references to struct xfs_defer_ops in XFS are associated with xfs_defer_add(). At this point, there are no more external xfs_defer_ops users left. All instances of xfs_defer_ops are embedded in the transaction, which means we can safely pass the transaction down to the dfops add interface. Update xfs_defer_add() to receive the transaction as a parameter. Various subsystems implement wrappers to allocate and construct the context specific data structures for the associated deferred operation type. Update these to also carry the transaction down as needed and clean up unused dfops parameters along the way. This removes most of the remaining references to struct xfs_defer_ops throughout the code and facilitates removal of the structure. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> [darrick: fix unused variable warnings with ftrace disabled] Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-08-01 22:20:34 +08:00
struct xfs_trans *tp,
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
xfs_fsblock_t fsb,
xfs_extlen_t len)
{
xfs: pass transaction to xfs_defer_add() The majority of remaining references to struct xfs_defer_ops in XFS are associated with xfs_defer_add(). At this point, there are no more external xfs_defer_ops users left. All instances of xfs_defer_ops are embedded in the transaction, which means we can safely pass the transaction down to the dfops add interface. Update xfs_defer_add() to receive the transaction as a parameter. Various subsystems implement wrappers to allocate and construct the context specific data structures for the associated deferred operation type. Update these to also carry the transaction down as needed and clean up unused dfops parameters along the way. This removes most of the remaining references to struct xfs_defer_ops throughout the code and facilitates removal of the structure. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> [darrick: fix unused variable warnings with ftrace disabled] Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-08-01 22:20:34 +08:00
struct xfs_mount *mp = tp->t_mountp;
xfs: queue deferred rmap ops for cow staging extent alloc/free in the right order Under the deferred rmap operation scheme, there's a certain order in which the rmap deferred ops have to be queued to maintain integrity during log replay. For alloc/map operations that order is cui -> rui; for free/unmap operations that order is cui -> rui -> efi. However, the initial refcount code got the ordering wrong in the free side of things because it queued refcount free op and an EFI and the refcount free op queued a rmap free op, resulting in the order cui -> efi -> rui. If we fail before the efd finishes, the efi recovery will try to do a wildcard rmap removal and the subsequent rui will fail to find the rmap and blow up. This didn't ever happen due to other screws up in handling unknown owner rmap removals, but those other screw ups broke recovery in other ways, so fix the ordering to follow the intended rules. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-12-08 11:07:03 +08:00
xfs: convert xfs_sb_version_has checks to use mount features This is a conversion of the remaining xfs_sb_version_has..(sbp) checks to use xfs_has_..(mp) feature checks. This was largely done with a vim replacement macro that did: :0,$s/xfs_sb_version_has\(.*\)&\(.*\)->m_sb/xfs_has_\1\2/g<CR> A couple of other variants were also used, and the rest touched up by hand. $ size -t fs/xfs/built-in.a text data bss dec hex filename before 1127533 311352 484 1439369 15f689 (TOTALS) after 1125360 311352 484 1437196 15ee0c (TOTALS) Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-08-19 09:46:55 +08:00
if (!xfs_has_reflink(mp))
xfs: remove unnecessary int returns from deferred refcount functions Remove the return value from the functions that schedule deferred refcount operations since they never fail and do not return status. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2019-08-27 08:06:04 +08:00
return;
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
xfs: queue deferred rmap ops for cow staging extent alloc/free in the right order Under the deferred rmap operation scheme, there's a certain order in which the rmap deferred ops have to be queued to maintain integrity during log replay. For alloc/map operations that order is cui -> rui; for free/unmap operations that order is cui -> rui -> efi. However, the initial refcount code got the ordering wrong in the free side of things because it queued refcount free op and an EFI and the refcount free op queued a rmap free op, resulting in the order cui -> efi -> rui. If we fail before the efd finishes, the efi recovery will try to do a wildcard rmap removal and the subsequent rui will fail to find the rmap and blow up. This didn't ever happen due to other screws up in handling unknown owner rmap removals, but those other screw ups broke recovery in other ways, so fix the ordering to follow the intended rules. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-12-08 11:07:03 +08:00
/* Remove rmap entry */
xfs: remove unnecessary int returns from deferred rmap functions Remove the return value from the functions that schedule deferred rmap operations since they never fail and do not return status. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2019-08-27 08:06:03 +08:00
xfs_rmap_free_extent(tp, XFS_FSB_TO_AGNO(mp, fsb),
xfs: queue deferred rmap ops for cow staging extent alloc/free in the right order Under the deferred rmap operation scheme, there's a certain order in which the rmap deferred ops have to be queued to maintain integrity during log replay. For alloc/map operations that order is cui -> rui; for free/unmap operations that order is cui -> rui -> efi. However, the initial refcount code got the ordering wrong in the free side of things because it queued refcount free op and an EFI and the refcount free op queued a rmap free op, resulting in the order cui -> efi -> rui. If we fail before the efd finishes, the efi recovery will try to do a wildcard rmap removal and the subsequent rui will fail to find the rmap and blow up. This didn't ever happen due to other screws up in handling unknown owner rmap removals, but those other screw ups broke recovery in other ways, so fix the ordering to follow the intended rules. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-12-08 11:07:03 +08:00
XFS_FSB_TO_AGBNO(mp, fsb), len, XFS_RMAP_OWN_COW);
xfs: remove unnecessary int returns from deferred refcount functions Remove the return value from the functions that schedule deferred refcount operations since they never fail and do not return status. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2019-08-27 08:06:04 +08:00
__xfs_refcount_add(tp, XFS_REFCOUNT_FREE_COW, fsb, len);
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
}
struct xfs_refcount_recovery {
struct list_head rr_list;
struct xfs_refcount_irec rr_rrec;
};
/* Stuff an extent on the recovery list. */
STATIC int
xfs_refcount_recover_extent(
xfs: convert open coded corruption check to use XFS_IS_CORRUPT Convert the last of the open coded corruption check and report idioms to use the XFS_IS_CORRUPT macro. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:53:22 +08:00
struct xfs_btree_cur *cur,
xfs: make the record pointer passed to query_range functions const The query_range functions are supposed to call a caller-supplied function on each record found in the dataset. These functions don't own the memory storing the record, so don't let them change the record. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2021-08-11 08:02:16 +08:00
const union xfs_btree_rec *rec,
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
void *priv)
{
struct list_head *debris = priv;
struct xfs_refcount_recovery *rr;
xfs: convert open coded corruption check to use XFS_IS_CORRUPT Convert the last of the open coded corruption check and report idioms to use the XFS_IS_CORRUPT macro. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-12 04:53:22 +08:00
if (XFS_IS_CORRUPT(cur->bc_mp,
be32_to_cpu(rec->refc.rc_refcount) != 1))
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
return -EFSCORRUPTED;
fs: xfs: Remove KM_NOSLEEP and KM_SLEEP. Since no caller is using KM_NOSLEEP and no callee branches on KM_SLEEP, we can remove KM_NOSLEEP and replace KM_SLEEP with 0. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-08-27 03:06:22 +08:00
rr = kmem_alloc(sizeof(struct xfs_refcount_recovery), 0);
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
xfs_refcount_btrec_to_irec(rec, &rr->rr_rrec);
list_add_tail(&rr->rr_list, debris);
return 0;
}
/* Find and remove leftover CoW reservations. */
int
xfs_refcount_recover_cow_leftovers(
struct xfs_mount *mp,
xfs: convert refcount btree cursor to use perags Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
struct xfs_perag *pag)
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
{
struct xfs_trans *tp;
struct xfs_btree_cur *cur;
struct xfs_buf *agbp;
struct xfs_refcount_recovery *rr, *n;
struct list_head debris;
union xfs_btree_irec low;
union xfs_btree_irec high;
xfs_fsblock_t fsb;
int error;
if (mp->m_sb.sb_agblocks >= XFS_REFC_COW_START)
return -EOPNOTSUPP;
xfs: avoid mount-time deadlock in CoW extent recovery If a malicious user corrupts the refcount btree to cause a cycle between different levels of the tree, the next mount attempt will deadlock in the CoW recovery routine while grabbing buffer locks. We can use the ability to re-grab a buffer that was previous locked to a transaction to avoid deadlocks, so do that here. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2017-05-16 10:16:15 +08:00
INIT_LIST_HEAD(&debris);
/*
* In this first part, we use an empty transaction to gather up
* all the leftover CoW extents so that we can subsequently
* delete them. The empty transaction is used to avoid
* a buffer lock deadlock if there happens to be a loop in the
* refcountbt because we're allowed to re-grab a buffer that is
* already attached to our transaction. When we're done
* recording the CoW debris we cancel the (empty) transaction
* and everything goes away cleanly.
*/
error = xfs_trans_alloc_empty(mp, &tp);
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
if (error)
return error;
xfs: avoid mount-time deadlock in CoW extent recovery If a malicious user corrupts the refcount btree to cause a cycle between different levels of the tree, the next mount attempt will deadlock in the CoW recovery routine while grabbing buffer locks. We can use the ability to re-grab a buffer that was previous locked to a transaction to avoid deadlocks, so do that here. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2017-05-16 10:16:15 +08:00
xfs: pass perag to xfs_alloc_read_agf() xfs_alloc_read_agf() initialises the perag if it hasn't been done yet, so it makes sense to pass it the perag rather than pull a reference from the buffer. This allows callers to be per-ag centric rather than passing mount/agno pairs everywhere. Whilst modifying the xfs_reflink_find_shared() function definition, declare it static and remove the extern declaration as it is an internal function only these days. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2022-07-07 17:07:40 +08:00
error = xfs_alloc_read_agf(pag, tp, 0, &agbp);
xfs: avoid mount-time deadlock in CoW extent recovery If a malicious user corrupts the refcount btree to cause a cycle between different levels of the tree, the next mount attempt will deadlock in the CoW recovery routine while grabbing buffer locks. We can use the ability to re-grab a buffer that was previous locked to a transaction to avoid deadlocks, so do that here. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2017-05-16 10:16:15 +08:00
if (error)
goto out_trans;
xfs: convert refcount btree cursor to use perags Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
cur = xfs_refcountbt_init_cursor(mp, tp, agbp, pag);
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
/* Find all the leftover CoW staging extents. */
memset(&low, 0, sizeof(low));
memset(&high, 0, sizeof(high));
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
low.rc.rc_domain = high.rc.rc_domain = XFS_REFC_DOMAIN_COW;
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
high.rc.rc_startblock = -1U;
error = xfs_btree_query_range(cur, &low, &high,
xfs_refcount_recover_extent, &debris);
xfs: clean up xfs_btree_del_cursor callers Less trivial cleanups of the error argument to xfs_btree_del_cursor; these require some minor code refactoring. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2018-07-20 03:29:10 +08:00
xfs_btree_del_cursor(cur, error);
xfs: avoid mount-time deadlock in CoW extent recovery If a malicious user corrupts the refcount btree to cause a cycle between different levels of the tree, the next mount attempt will deadlock in the CoW recovery routine while grabbing buffer locks. We can use the ability to re-grab a buffer that was previous locked to a transaction to avoid deadlocks, so do that here. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2017-05-16 10:16:15 +08:00
xfs_trans_brelse(tp, agbp);
xfs_trans_cancel(tp);
xfs: clean up xfs_btree_del_cursor callers Less trivial cleanups of the error argument to xfs_btree_del_cursor; these require some minor code refactoring. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2018-07-20 03:29:10 +08:00
if (error)
goto out_free;
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
/* Now iterate the list to free the leftovers */
xfs: avoid mount-time deadlock in CoW extent recovery If a malicious user corrupts the refcount btree to cause a cycle between different levels of the tree, the next mount attempt will deadlock in the CoW recovery routine while grabbing buffer locks. We can use the ability to re-grab a buffer that was previous locked to a transaction to avoid deadlocks, so do that here. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2017-05-16 10:16:15 +08:00
list_for_each_entry_safe(rr, n, &debris, rr_list) {
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
/* Set up transaction. */
error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, 0, 0, 0, &tp);
if (error)
goto out_free;
xfs: convert refcount btree cursor to use perags Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-06-02 08:48:24 +08:00
trace_xfs_refcount_recover_extent(mp, pag->pag_agno,
&rr->rr_rrec);
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
/* Free the orphan record */
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
fsb = XFS_AGB_TO_FSB(mp, pag->pag_agno,
rr->rr_rrec.rc_startblock);
xfs: remove unnecessary int returns from deferred refcount functions Remove the return value from the functions that schedule deferred refcount operations since they never fail and do not return status. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2019-08-27 08:06:04 +08:00
xfs_refcount_free_cow_extent(tp, fsb,
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
rr->rr_rrec.rc_blockcount);
/* Free the block. */
xfs: rename xfs_bmap_add_free to xfs_free_extent_later xfs_bmap_add_free isn't a block mapping function; it schedules deferred freeing operations for a later point in a compound transaction chain. While it's primarily used by bunmapi, its use has expanded beyond that. Move it to xfs_alloc.c and rename the function since it's now general freeing functionality. Bring the slab cache bits in line with the way we handle the other intent items. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
2021-10-13 05:17:01 +08:00
xfs_free_extent_later(tp, fsb, rr->rr_rrec.rc_blockcount, NULL);
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
error = xfs_trans_commit(tp);
if (error)
xfs: rework refcount cow recovery error handling The error handling in xfs_refcount_recover_cow_leftovers is confused and can potentially leak memory, so rework it to release resources correctly on error. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reported-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-10-10 14:23:07 +08:00
goto out_free;
xfs: avoid mount-time deadlock in CoW extent recovery If a malicious user corrupts the refcount btree to cause a cycle between different levels of the tree, the next mount attempt will deadlock in the CoW recovery routine while grabbing buffer locks. We can use the ability to re-grab a buffer that was previous locked to a transaction to avoid deadlocks, so do that here. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2017-05-16 10:16:15 +08:00
list_del(&rr->rr_list);
kmem_free(rr);
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
}
xfs: avoid mount-time deadlock in CoW extent recovery If a malicious user corrupts the refcount btree to cause a cycle between different levels of the tree, the next mount attempt will deadlock in the CoW recovery routine while grabbing buffer locks. We can use the ability to re-grab a buffer that was previous locked to a transaction to avoid deadlocks, so do that here. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2017-05-16 10:16:15 +08:00
return error;
out_trans:
xfs_trans_cancel(tp);
xfs: store in-progress CoW allocations in the refcount btree Due to the way the CoW algorithm in XFS works, there's an interval during which blocks allocated to handle a CoW can be lost -- if the FS goes down after the blocks are allocated but before the block remapping takes place. This is exacerbated by the cowextsz hint -- allocated reservations can sit around for a while, waiting to get used. Since the refcount btree doesn't normally store records with refcount of 1, we can use it to record these in-progress extents. In-progress blocks cannot be shared because they're not user-visible, so there shouldn't be any conflicts with other programs. This is a better solution than holding EFIs during writeback because (a) EFIs can't be relogged currently, (b) even if they could, EFIs are bound by available log space, which puts an unnecessary upper bound on how much CoW we can have in flight, and (c) we already have a mechanism to track blocks. At mount time, read the refcount records and free anything we find with a refcount of 1 because those were in-progress when the FS went down. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 00:11:39 +08:00
out_free:
/* Free the leftover list */
list_for_each_entry_safe(rr, n, &debris, rr_list) {
list_del(&rr->rr_list);
kmem_free(rr);
}
return error;
}
xfs: add scrub cross-referencing helpers for the refcount btrees Add a couple of functions to the refcount btrees that will be used to cross-reference metadata against the refcountbt. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-01-17 10:52:14 +08:00
/* Is there a record covering a given extent? */
int
xfs_refcount_has_record(
struct xfs_btree_cur *cur,
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
enum xfs_refc_domain domain,
xfs: add scrub cross-referencing helpers for the refcount btrees Add a couple of functions to the refcount btrees that will be used to cross-reference metadata against the refcountbt. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-01-17 10:52:14 +08:00
xfs_agblock_t bno,
xfs_extlen_t len,
bool *exists)
{
union xfs_btree_irec low;
union xfs_btree_irec high;
memset(&low, 0, sizeof(low));
low.rc.rc_startblock = bno;
memset(&high, 0xFF, sizeof(high));
high.rc.rc_startblock = bno + len - 1;
xfs: track cow/shared record domains explicitly in xfs_refcount_irec Just prior to committing the reflink code into upstream, the xfs maintainer at the time requested that I find a way to shard the refcount records into two domains -- one for records tracking shared extents, and a second for tracking CoW staging extents. The idea here was to minimize mount time CoW reclamation by pushing all the CoW records to the right edge of the keyspace, and it was accomplished by setting the upper bit in rc_startblock. We don't allow AGs to have more than 2^31 blocks, so the bit was free. Unfortunately, this was a very late addition to the codebase, so most of the refcount record processing code still treats rc_startblock as a u32 and pays no attention to whether or not the upper bit (the cow flag) is set. This is a weakness is theoretically exploitable, since we're not fully validating the incoming metadata records. Fuzzing demonstrates practical exploits of this weakness. If the cow flag of a node block key record is corrupted, a lookup operation can go to the wrong record block and start returning records from the wrong cow/shared domain. This causes the math to go all wrong (since cow domain is still implicit in the upper bit of rc_startblock) and we can crash the kernel by tricking xfs into jumping into a nonexistent AG and tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL. To fix this, start tracking the domain as an explicit part of struct xfs_refcount_irec, adjust all refcount functions to check the domain of a returned record, and alter the function definitions to accept them where necessary. Found by fuzzing keys[2].cowflag = add in xfs/464. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-11 00:06:24 +08:00
low.rc.rc_domain = high.rc.rc_domain = domain;
xfs: add scrub cross-referencing helpers for the refcount btrees Add a couple of functions to the refcount btrees that will be used to cross-reference metadata against the refcountbt. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-01-17 10:52:14 +08:00
return xfs_btree_has_record(cur, &low, &high, exists);
}
xfs: create slab caches for frequently-used deferred items Create slab caches for the high-level structures that coordinate deferred intent items, since they're used fairly heavily. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
2021-10-13 05:11:01 +08:00
int __init
xfs_refcount_intent_init_cache(void)
{
xfs_refcount_intent_cache = kmem_cache_create("xfs_refc_intent",
sizeof(struct xfs_refcount_intent),
0, 0, NULL);
return xfs_refcount_intent_cache != NULL ? 0 : -ENOMEM;
}
void
xfs_refcount_intent_destroy_cache(void)
{
kmem_cache_destroy(xfs_refcount_intent_cache);
xfs_refcount_intent_cache = NULL;
}
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