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Commit Graph

2168 Commits

Author SHA1 Message Date
Bob Peterson
b3422cacdd gfs2: Rework how rgrp buffer_heads are managed
Before this patch, the rgrp code had a serious problem related to
how it managed buffer_heads for resource groups. The problem caused
file system corruption, especially in cases of journal replay.

When an rgrp glock was demoted to transfer ownership to a
different cluster node, do_xmote() first calls rgrp_go_sync and then
rgrp_go_inval, as expected. When it calls rgrp_go_sync, that called
gfs2_rgrp_brelse() that dropped the buffer_head reference count.
In most cases, the reference count went to zero, which is right.
However, there were other places where the buffers are handled
differently.

After rgrp_go_sync, do_xmote called rgrp_go_inval which called
gfs2_rgrp_brelse a second time, then rgrp_go_inval's call to
truncate_inode_pages_range would get rid of the pages in memory,
but only if the reference count drops to 0.

Unfortunately, gfs2_rgrp_brelse was setting bi->bi_bh = NULL.
So when rgrp_go_sync called gfs2_rgrp_brelse, it lost the pointer
to the buffer_heads in cases where the reference count was still 1.
Therefore, when rgrp_go_inval called gfs2_rgrp_brelse a second time,
it failed the check for "if (bi->bi_bh)" and thus failed to call
brelse a second time. Because of that, the reference count on those
buffers sometimes failed to drop from 1 to 0. And that caused
function truncate_inode_pages_range to keep the pages in page cache
rather than freeing them.

The next time the rgrp glock was acquired, the metadata read of
the rgrp buffers re-used the pages in memory, which were now
wrong because they were likely modified by the other node who
acquired the glock in EX (which is why we demoted the glock).
This re-use of the page cache caused corruption because changes
made by the other nodes were never seen, so the bitmaps were
inaccurate.

For some reason, the problem became most apparent when journal
replay forced the replay of rgrps in memory, which caused newer
rgrp data to be overwritten by the older in-core pages.

A big part of the problem was that the rgrp buffer were released
in multiple places: The go_unlock function would release them when
the glock was released rather than when the glock is demoted,
which is clearly wrong because our intent was to cache them until
the glock is demoted from SH or EX.

This patch attempts to clean up the mess and make one consistent
and centralized mechanism for managing the rgrp buffer_heads by
implementing several changes:

1. It eliminates the call to gfs2_rgrp_brelse() from rgrp_go_sync.
   We don't want to release the buffers or zero the pointers when
   syncing for the reasons stated above. It only makes sense to
   release them when the glock is actually invalidated (go_inval).
   And when we do, then we set the bh pointers to NULL.
2. The go_unlock function (which was only used for rgrps) is
   eliminated, as we've talked about doing many times before.
   The go_unlock function was called too early in the glock dq
   process, and should not happen until the glock is invalidated.
3. It also eliminates the call to rgrp_brelse in gfs2_clear_rgrpd.
   That will now happen automatically when the rgrp glocks are
   demoted, and shouldn't happen any sooner or later than that.
   Instead, function gfs2_clear_rgrpd has been modified to demote
   the rgrp glocks, and therefore, free those pages, before the
   remaining glocks are culled by gfs2_gl_hash_clear. This
   prevents the gl_object from hanging around when the glocks are
   culled.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-02-10 07:39:48 -06:00
Bob Peterson
30fe70a85a gfs2: clear ail1 list when gfs2 withdraws
This patch fixes a bug in which function gfs2_log_flush can get into
an infinite loop when a gfs2 file system is withdrawn. The problem
is the infinite loop "for (;;)" in gfs2_log_flush which would never
finish because the io error and subsequent withdraw prevented the
items from being taken off the ail list.

This patch tries to clean up the mess by allowing withdraw situations
to move not-in-flight buffer_heads to the ail2 list, where they will
be dealt with later.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-02-10 07:39:48 -06:00
Bob Peterson
69511080bd gfs2: Introduce concept of a pending withdraw
File system withdraws can be delayed when inconsistencies are
discovered when we cannot withdraw immediately, for example, when
critical spin_locks are held. But delaying the withdraw can cause
gfs2 to ignore the error and keep running for a short period of time.
For example, an rgrp glock may be dequeued and demoted while there
are still buffers that haven't been properly revoked, due to io
errors writing to the journal.

This patch introduces a new concept of a pending withdraw, which
means an inconsistency has been discovered and we need to withdraw
at the earliest possible opportunity. In these cases, we aren't
quite withdrawn yet, but we still need to not dequeue glocks and
other critical things. If we dequeue the glocks and the withdraw
results in our journal being replayed, the replay could overwrite
data that's been modified by a different node that acquired the
glock in the meantime.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-02-10 07:39:47 -06:00
Andreas Gruenbacher
8e28ef1f2f gfs2: Return bool from gfs2_assert functions
The gfs2_assert functions only print messages when the filesystem hasn't been
withdrawn yet, and they indicate whether or not they've printed something in
their return value.  However, none of the callers use that information, so
simply return whether or not the assert has failed.

(The gfs2_assert functions are still backwards; they return false when an
assertion is true.)

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2020-02-10 07:39:47 -06:00
Andreas Gruenbacher
a5ca2f1cb6 gfs2: Turn gfs2_consist into void functions
Change the various gfs2_consist functions to return void.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2020-02-10 07:39:46 -06:00
Andreas Gruenbacher
d7e7ab3f1e gfs2: Remove usused cluster_wide arguments of gfs2_consist functions
These arguments are always passed as 0, and they are never evaluated.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2020-02-10 07:39:45 -06:00
Andreas Gruenbacher
8dc88ac68d gfs2: Report errors before withdraw
In gfs2_rgrp_verify and compute_bitstructs, make sure to report errors before
withdrawing the filesystem: otherwise, when we withdraw first and withdraw is
configured to panic, we'll never get to the error reporting.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2020-02-10 07:39:45 -06:00
Andreas Gruenbacher
badb55ec20 gfs2: Split gfs2_lm_withdraw into two functions
Split gfs2_lm_withdraw into a function that prints an error message and a
function that withdraws the filesystem.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2020-02-10 07:39:44 -06:00
Andreas Gruenbacher
6e5e41e2dc gfs2: fix O_SYNC write handling
In gfs2_file_write_iter, for direct writes, the error checking in the buffered
write fallback case is incomplete.  This can cause inode write errors to go
undetected.  Fix and clean up gfs2_file_write_iter along the way.

Based on a proposed fix by Christoph Hellwig <hch@lst.de>.

Fixes: 967bcc91b0 ("gfs2: iomap direct I/O support")
Cc: stable@vger.kernel.org # v4.19+
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-02-06 18:49:41 +01:00
Christoph Hellwig
4c0e8dda60 gfs2: move setting current->backing_dev_info
Set current->backing_dev_info just around the buffered write calls to
prepare for the next fix.

Fixes: 967bcc91b0 ("gfs2: iomap direct I/O support")
Cc: stable@vger.kernel.org # v4.19+
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-02-06 17:35:23 +01:00
Abhi Das
7582026f6f gfs2: fix gfs2_find_jhead that returns uninitialized jhead with seq 0
When the first log header in a journal happens to have a sequence
number of 0, a bug in gfs2_find_jhead() causes it to prematurely exit,
and return an uninitialized jhead with seq 0. This can cause failures
in the caller. For instance, a mount fails in one test case.

The correct behavior is for it to continue searching through the journal
to find the correct journal head with the highest sequence number.

Fixes: f4686c26ec ("gfs2: read journal in large chunks")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-02-06 17:35:23 +01:00
Bob Peterson
a31b4ec539 Revert "gfs2: eliminate tr_num_revoke_rm"
This reverts commit e955537e32.

Before patch e955537e32, tr_num_revoke tracked the number of revokes
added to the transaction, and tr_num_revoke_rm tracked how many
revokes were removed. But since revokes are queued off the sdp
(superblock) pointer, some transactions could remove more revokes
than they added. (e.g. revokes added by a different process).
Commit e955537e32 eliminated transaction variable tr_num_revoke_rm,
but in order to do so, it changed the accounting to always use
tr_num_revoke for its math. Since you can remove more revokes than
you add, tr_num_revoke could now become a negative value.
This negative value broke the assert in function gfs2_trans_end:

	if (gfs2_assert_withdraw(sdp, (nbuf <=3D tr->tr_blocks) &&
			       (tr->tr_num_revoke <=3D tr->tr_revokes)))

One way to fix this is to simply remove the tr_num_revoke clause
from the assert and allow the value to become negative. Andreas
didn't like that idea, so instead, we decided to revert e955537e32.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-01-28 15:04:53 +01:00
Alex Shi
c04f2e0dd5 gfs2: remove unused LBIT macros
Since commit 223b2b889f ("GFS2: Fix alignment issue and tidy
gfs2_bitfit"), these 3 macros aren't used anymore, so remove them.

Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-01-21 11:19:45 +01:00
Alex Shi
b3ca4e447d fs/gfs2: remove unused IS_DINODE and IS_LEAF macros
Since commit 1579343a73 ("GFS2: Remove dirent_first() function"),
these macros aren't used any more, so remove them.

Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-01-21 11:19:38 +01:00
Andreas Gruenbacher
f7be987b82 gfs2: Remove GFS2_MIN_LVB_SIZE define
The dlm lockspace is set up to have lock value blocks of GDLM_LVB_SIZE bytes,
and dlm is the only lock manager we support, so there is no point in claiming
that the lock value block could have any other size.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-01-20 08:46:53 +01:00
Andreas Gruenbacher
5d43975859 gfs2: Fix incorrect variable name
Rename sd_log_commited_revoke to sd_log_committed_revoke.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-01-20 08:46:53 +01:00
Andreas Gruenbacher
2b0fb353c0 gfs2: Avoid access time thrashing in gfs2_inode_lookup
In gfs2_inode_lookup, we initialize inode->i_atime to the lowest
possibly value after gfs2_inode_refresh may already have been called.
This should be the other way around, but we didn't notice because
usually the inode type is known from the directory entry and so
gfs2_inode_lookup won't call gfs2_inode_refresh.

In addition, only initialize ip->i_no_formal_ino from no_formal_ino when
actually needed.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-01-15 15:20:07 +01:00
Bob Peterson
e556280d36 gfs2: minor cleanup: remove unneeded variable ret in gfs2_jdata_writepage
This patch simply removes variable ret, which is used to store the return
code of its call to __gfs2_jdata_writepage, in favor of just returning the
result directly.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2020-01-08 10:39:57 -06:00
Bob Peterson
2e9eeaa117 gfs2: eliminate ssize parameter from gfs2_struct2blk
Every caller of function gfs2_struct2blk specified sizeof(u64).

This patch eliminates the unnecessary parameter and replaces the
size calculation with a new superblock variable that is computed
to be the maximum number of block pointers we can fit inside a
log descriptor, as is done for pointers per dinode and indirect
block.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andrew Price <anprice@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-01-07 18:46:06 +01:00
Andreas Gruenbacher
eed0f953b9 gfs2: Another gfs2_find_jhead fix
On filesystems with a block size smaller than the page size,
gfs2_find_jhead can split a page across two bios (for example, when
blocks are not allocated consecutively).  When that happens, the first
bio that completes will unlock the page in its bi_end_io handler even
though the page hasn't been read completely yet.  Fix that by using a
chained bio for the rest of the page.

While at it, clean up the sector calculation logic in
gfs2_log_alloc_bio.  In gfs2_find_jhead, simplify the disk block and
offset calculation logic and fix a variable name.

Fixes: f4686c26ec ("gfs2: read journal in large chunks")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-01-07 12:30:36 +01:00
Linus Torvalds
3f1266ec70 GFS2 changes for this merge window:
Bob's extensive filesystem withdrawal and recovery testing:
 - Don't write log headers after file system withdraw
 - clean up iopen glock mess in gfs2_create_inode
 - Close timing window with GLF_INVALIDATE_IN_PROGRESS
 - Abort gfs2_freeze if io error is seen
 - Don't loop forever in gfs2_freeze if withdrawn
 - fix infinite loop in gfs2_ail1_flush on io error
 - Introduce function gfs2_withdrawn
 - fix glock reference problem in gfs2_trans_remove_revoke
 
 Filesystems with a block size smaller than the page size:
 - Fix end-of-file handling in gfs2_page_mkwrite
 - Improve mmap write vs. punch_hole consistency
 
 Other:
 - Remove active journal side effect from gfs2_write_log_header
 - Multi-block allocations in gfs2_page_mkwrite
 
 Minor cleanups and coding style fixes:
 - Remove duplicate call from gfs2_create_inode
 - make gfs2_log_shutdown static
 - make gfs2_fs_parameters static
 - Some whitespace cleanups
 - removed unnecessary semicolon
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Merge tag 'gfs2-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2

Pull GFS2 updates from Andreas Gruenbacher:
 "Bob's extensive filesystem withdrawal and recovery testing:
   - don't write log headers after file system withdraw
   - clean up iopen glock mess in gfs2_create_inode
   - close timing window with GLF_INVALIDATE_IN_PROGRESS
   - abort gfs2_freeze if io error is seen
   - don't loop forever in gfs2_freeze if withdrawn
   - fix infinite loop in gfs2_ail1_flush on io error
   - introduce function gfs2_withdrawn
   - fix glock reference problem in gfs2_trans_remove_revoke

  Filesystems with a block size smaller than the page size:
   - fix end-of-file handling in gfs2_page_mkwrite
   - improve mmap write vs. punch_hole consistency

  Other:
   - remove active journal side effect from gfs2_write_log_header
   - multi-block allocations in gfs2_page_mkwrite

  Minor cleanups and coding style fixes:
   - remove duplicate call from gfs2_create_inode
   - make gfs2_log_shutdown static
   - make gfs2_fs_parameters static
   - some whitespace cleanups
   - removed unnecessary semicolon"

* tag 'gfs2-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: Don't write log headers after file system withdraw
  gfs2: Remove duplicate call from gfs2_create_inode
  gfs2: clean up iopen glock mess in gfs2_create_inode
  gfs2: Close timing window with GLF_INVALIDATE_IN_PROGRESS
  gfs2: Abort gfs2_freeze if io error is seen
  gfs2: Don't loop forever in gfs2_freeze if withdrawn
  gfs2: fix infinite loop in gfs2_ail1_flush on io error
  gfs2: Introduce function gfs2_withdrawn
  gfs2: fix glock reference problem in gfs2_trans_remove_revoke
  gfs2: make gfs2_log_shutdown static
  gfs2: Remove active journal side effect from gfs2_write_log_header
  gfs2: Fix end-of-file handling in gfs2_page_mkwrite
  gfs2: Multi-block allocations in gfs2_page_mkwrite
  gfs2: Improve mmap write vs. punch_hole consistency
  gfs2: make gfs2_fs_parameters static
  gfs2: Some whitespace cleanups
  gfs2: removed unnecessary semicolon
2019-12-05 13:20:11 -08:00
Linus Torvalds
0da522107e compat_ioctl: remove most of fs/compat_ioctl.c
As part of the cleanup of some remaining y2038 issues, I came to
 fs/compat_ioctl.c, which still has a couple of commands that need support
 for time64_t.
 
 In completely unrelated work, I spent time on cleaning up parts of this
 file in the past, moving things out into drivers instead.
 
 After Al Viro reviewed an earlier version of this series and did a lot
 more of that cleanup, I decided to try to completely eliminate the rest
 of it and move it all into drivers.
 
 This series incorporates some of Al's work and many patches of my own,
 but in the end stops short of actually removing the last part, which is
 the scsi ioctl handlers. I have patches for those as well, but they need
 more testing or possibly a rewrite.
 
 Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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Merge tag 'compat-ioctl-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground

Pull removal of most of fs/compat_ioctl.c from Arnd Bergmann:
 "As part of the cleanup of some remaining y2038 issues, I came to
  fs/compat_ioctl.c, which still has a couple of commands that need
  support for time64_t.

  In completely unrelated work, I spent time on cleaning up parts of
  this file in the past, moving things out into drivers instead.

  After Al Viro reviewed an earlier version of this series and did a lot
  more of that cleanup, I decided to try to completely eliminate the
  rest of it and move it all into drivers.

  This series incorporates some of Al's work and many patches of my own,
  but in the end stops short of actually removing the last part, which
  is the scsi ioctl handlers. I have patches for those as well, but they
  need more testing or possibly a rewrite"

* tag 'compat-ioctl-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground: (42 commits)
  scsi: sd: enable compat ioctls for sed-opal
  pktcdvd: add compat_ioctl handler
  compat_ioctl: move SG_GET_REQUEST_TABLE handling
  compat_ioctl: ppp: move simple commands into ppp_generic.c
  compat_ioctl: handle PPPIOCGIDLE for 64-bit time_t
  compat_ioctl: move PPPIOCSCOMPRESS to ppp_generic
  compat_ioctl: unify copy-in of ppp filters
  tty: handle compat PPP ioctls
  compat_ioctl: move SIOCOUTQ out of compat_ioctl.c
  compat_ioctl: handle SIOCOUTQNSD
  af_unix: add compat_ioctl support
  compat_ioctl: reimplement SG_IO handling
  compat_ioctl: move WDIOC handling into wdt drivers
  fs: compat_ioctl: move FITRIM emulation into file systems
  gfs2: add compat_ioctl support
  compat_ioctl: remove unused convert_in_user macro
  compat_ioctl: remove last RAID handling code
  compat_ioctl: remove /dev/raw ioctl translation
  compat_ioctl: remove PCI ioctl translation
  compat_ioctl: remove joystick ioctl translation
  ...
2019-12-01 13:46:15 -08:00
Linus Torvalds
3b266a52d8 New code for 5.5:
- Make iomap_dio_rw callers explicitly tell us if they want us to wait
 - Port the xfs writeback code to iomap to complete the buffered io
   library functions
 - Refactor the unshare code to share common pieces
 - Add support for performing copy on write with buffered writes
 - Other minor fixes
 - Fix unchecked return in iomap_bmap
 - Fix a type casting bug in a ternary statement in iomap_dio_bio_actor
 - Improve tracepoints for easier diagnostic ability
 - Fix pipe page leakage in directio reads
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Merge tag 'iomap-5.5-merge-11' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull iomap updates from Darrick Wong:
 "In this release, we hoisted as much of XFS' writeback code into iomap
  as was practicable, refactored the unshare file data function, added
  the ability to perform buffered io copy on write, and tweaked various
  parts of the directio implementation as needed to port ext4's directio
  code (that will be a separate pull).

  Summary:

   - Make iomap_dio_rw callers explicitly tell us if they want us to
     wait

   - Port the xfs writeback code to iomap to complete the buffered io
     library functions

   - Refactor the unshare code to share common pieces

   - Add support for performing copy on write with buffered writes

   - Other minor fixes

   - Fix unchecked return in iomap_bmap

   - Fix a type casting bug in a ternary statement in
     iomap_dio_bio_actor

   - Improve tracepoints for easier diagnostic ability

   - Fix pipe page leakage in directio reads"

* tag 'iomap-5.5-merge-11' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (31 commits)
  iomap: Fix pipe page leakage during splicing
  iomap: trace iomap_appply results
  iomap: fix return value of iomap_dio_bio_actor on 32bit systems
  iomap: iomap_bmap should check iomap_apply return value
  iomap: Fix overflow in iomap_page_mkwrite
  fs/iomap: remove redundant check in iomap_dio_rw()
  iomap: use a srcmap for a read-modify-write I/O
  iomap: renumber IOMAP_HOLE to 0
  iomap: use write_begin to read pages to unshare
  iomap: move the zeroing case out of iomap_read_page_sync
  iomap: ignore non-shared or non-data blocks in xfs_file_dirty
  iomap: always use AOP_FLAG_NOFS in iomap_write_begin
  iomap: remove the unused iomap argument to __iomap_write_end
  iomap: better document the IOMAP_F_* flags
  iomap: enhance writeback error message
  iomap: pass a struct page to iomap_finish_page_writeback
  iomap: cleanup iomap_ioend_compare
  iomap: move struct iomap_page out of iomap.h
  iomap: warn on inline maps in iomap_writepage_map
  iomap: lift the xfs writeback code to iomap
  ...
2019-11-30 10:44:49 -08:00
Bob Peterson
ade4808893 gfs2: Don't write log headers after file system withdraw
Before this patch, when a node withdrew a gfs2 file system, it
wrote a (clean) unmount log header. That's wrong. You don't want
to write anything to the journal once you're withdrawn because
that's acknowledging that the transaction is complete and the
journal is in good shape, neither of which may be a valid
assumption when the file system is withdrawn. This is especially
true if the withdraw was caused due to io errors writing to the
journal in the first place. The best course of action is to leave
the journal "as is" until it may be safely replayed during
journal recovery, regardless of whether it's done by this node or
another.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2019-11-21 11:37:41 +01:00
Andreas Gruenbacher
8f81180ac1 gfs2: Remove duplicate call from gfs2_create_inode
In gfs2_create_inode, gfs2_set_inode_blocks is called twice for no good reason.
Remove the unnecessary call.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2019-11-21 11:37:12 +01:00
Bob Peterson
2c47c1be51 gfs2: clean up iopen glock mess in gfs2_create_inode
Before this patch, gfs2_create_inode had a use-after-free for the
iopen glock in some error paths because it did this:

	gfs2_glock_put(io_gl);
fail_gunlock2:
	if (io_gl)
		clear_bit(GLF_INODE_CREATING, &io_gl->gl_flags);

In some cases, the io_gl was used for create and only had one
reference, so the glock might be freed before the clear_bit().
This patch tries to straighten it out by only jumping to the
error paths where iopen is properly set, and moving the
gfs2_glock_put after the clear_bit.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2019-11-19 21:02:01 +01:00
Bob Peterson
d99724c3c3 gfs2: Close timing window with GLF_INVALIDATE_IN_PROGRESS
This patch closes a timing window in which two processes compete
and overlap in the execution of do_xmote for the same glock:

             Process A                              Process B
   ------------------------------------   -----------------------------
1. Grabs gl_lockref and calls do_xmote
2.                                        Grabs gl_lockref but is blocked
3. Sets GLF_INVALIDATE_IN_PROGRESS
4. Unlocks gl_lockref
5.                                        Calls do_xmote
6. Call glops->go_sync
7. test_and_clear_bit GLF_DIRTY
8. Call gfs2_log_flush                    Call glops->go_sync
9. (slow IO, so it blocks a long time)    test_and_clear_bit GLF_DIRTY
                                          It's not dirty (step 7) returns
10.                                       Tests GLF_INVALIDATE_IN_PROGRESS
11.                                       Calls go_inval (rgrp_go_inval)
12.                                       gfs2_rgrp_relse does brelse
13.                                       truncate_inode_pages_range
14.                                       Calls lm_lock UN

In step 14 we've just told dlm to give the glock to another node
when, in fact, process A has not finished the IO and synced all
buffer_heads to disk and make sure their revokes are done.

This patch fixes the problem by changing the GLF_INVALIDATE_IN_PROGRESS
to use test_and_set_bit, and if the bit is already set, process B just
ignores it and trusts that process A will do the do_xmote in the proper
order.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2019-11-15 18:21:59 +01:00
Bob Peterson
52b1cdcb7a gfs2: Abort gfs2_freeze if io error is seen
Before this patch, an io error, such as -EIO writing to the journal
would cause function gfs2_freeze to go into an infinite loop,
continuously retrying the freeze operation. But nothing ever clears
the -EIO except unmount after withdraw, which is impossible if the
freeze operation never ends (fails). Instead you get:

[ 6499.767994] gfs2: fsid=dm-32.0: error freezing FS: -5
[ 6499.773058] gfs2: fsid=dm-32.0: retrying...
[ 6500.791957] gfs2: fsid=dm-32.0: error freezing FS: -5
[ 6500.797015] gfs2: fsid=dm-32.0: retrying...

This patch adds a check for -EIO in gfs2_freeze, and if seen, it
dequeues the freeze glock, aborts the loop and returns the error.
Also, there's no need to pass the freeze holder to function
gfs2_lock_fs_check_clean since it's only called in one place and
it's a well-known superblock pointer, so this simplifies that.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2019-11-15 17:57:30 +01:00
Bob Peterson
60528afa78 gfs2: Don't loop forever in gfs2_freeze if withdrawn
Before this patch, function gfs2_freeze would loop forever if the
filesystem it tries to freeze is withdrawn. That's because function
gfs2_lock_fs_check_clean tries to enqueue the glock of the journal and
the gfs2_glock returns -EIO because you can't enqueue a journaled glock
after a withdraw.

Move the check for file system withdraw inside the loop so that the loop
can end when withdraw occurs.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2019-11-14 19:47:05 +01:00
Bob Peterson
f155f5e010 gfs2: fix infinite loop in gfs2_ail1_flush on io error
Before this patch, an IO error encountered in function gfs2_ail1_flush
would cause a deadlock: because of the io error (and its resulting
withdrawn state), buffers stopped being written to the journal.
Buffers would remain on the ail1 list, so gfs2_ail1_start_one would
return 1 to indicate dirty buffers were still on the ail1 list.
However, when function gfs2_ail1_flush got a non-zero return code,
it would goto restart to retry the writes, which meant it would never
finish, and thus the infinite loop.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2019-11-14 19:46:43 +01:00
Bob Peterson
eb43e660c0 gfs2: Introduce function gfs2_withdrawn
Add function gfs2_withdrawn and replace all checks for the SDF_WITHDRAWN
bit to call it. This does not change the logic or function of gfs2, and
it facilitates later improvements to the withdraw sequence.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2019-11-14 19:46:18 +01:00
Bob Peterson
fe5e7ba11f gfs2: fix glock reference problem in gfs2_trans_remove_revoke
Commit 9287c6452d fixed a situation in which gfs2 could use a glock
after it had been freed. To do that, it temporarily added a new glock
reference by calling gfs2_glock_hold in function gfs2_add_revoke.
However, if the bd element was removed by gfs2_trans_remove_revoke, it
failed to drop the additional reference.

This patch adds logic to gfs2_trans_remove_revoke to properly drop the
additional glock reference.

Fixes: 9287c6452d ("gfs2: Fix occasional glock use-after-free")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2019-11-14 16:51:00 +01:00
Bob Peterson
feed98a8e5 gfs2: make gfs2_log_shutdown static
Function gfs2_log_shutdown is only called from within log.c. This
patch removes the extern declaration and makes it static.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2019-11-14 16:50:56 +01:00
Andreas Gruenbacher
19ebc050e4 gfs2: Remove active journal side effect from gfs2_write_log_header
Function gfs2_write_log_header can be used to write a log header into any of
the journals of a filesystem.  When used on the node's own journal,
gfs2_write_log_header advances the current position in the log
(sdp->sd_log_flush_head) as a side effect, through function gfs2_log_bmap.

This is confusing, and it also means that we can't use gfs2_log_bmap for other
journals even if they have an extent map.  So clean this mess up by not
advancing sdp->sd_log_flush_head in gfs2_write_log_header or gfs2_log_bmap
anymore and making that a responsibility of the callers instead.

This is related to commit 7c70b89695 ("gfs2: clean_journal improperly set
sd_log_flush_head").

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2019-11-12 15:17:53 +01:00
Andreas Gruenbacher
184b4e6085 gfs2: Fix end-of-file handling in gfs2_page_mkwrite
When the filesystem block size is smaller than the page size, the last
page may contain blocks that lie entirely beyond the end of the file.
Make sure to only allocate blocks that lie at least partially in the
file.  Allocating blocks beyond that isn't useful, and what's more, they
will not be zeroed out and may end up containing random data.

With that change in place, make sure we'll still always unstuff stuffed
inodes: iomap_writepage and iomap_writepages currently can't handle
stuffed files.

In addition, simplify and move the end-of-file check further to the top
in gfs2_page_mkwrite to avoid weird side effects like unstuffing when
we're not.

Fixes xfstest generic/263.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2019-11-07 21:02:35 +01:00
Andreas Gruenbacher
f53056c430 gfs2: Multi-block allocations in gfs2_page_mkwrite
In gfs2_page_mkwrite's gfs2_allocate_page_backing helper, try to
allocate as many blocks at once as we need.  Pass in the size of the
requested allocation.

Fixes: 35af80aef9 ("gfs2: don't use buffer_heads in gfs2_allocate_page_backing")
Cc: stable@vger.kernel.org # v5.3+
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2019-11-07 21:02:02 +01:00
Andreas Gruenbacher
39c3a948ec gfs2: Improve mmap write vs. punch_hole consistency
When punching a hole in a file, use filemap_write_and_wait_range to
write back any dirty pages in the range of the hole.  As a side effect,
if the hole isn't page aligned, this marks unaligned pages at the
beginning and the end of the hole read-only.  This is required when the
block size is smaller than the page size: when those pages are written
to again after the hole punching, we must make sure that page_mkwrite is
called for those pages so that the page will be fully allocated and any
blocks turned into holes from the hole punching will be reallocated.
(If a page is writably mapped, page_mkwrite won't be called.)

Fixes xfstest generic/567.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2019-11-07 21:01:04 +01:00
Ben Dooks (Codethink)
1a48049adb gfs2: make gfs2_fs_parameters static
The gfs2_fs_parameters is not used outside the unit
it is declared in, so make it static.

Fixes the following sparse warning:

fs/gfs2/ops_fstype.c:1331:39: warning: symbol 'gfs2_fs_parameters' was not declared. Should it be static?

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Reviewed-by: Andrew Price <anprice@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2019-10-30 12:17:04 +01:00
Andreas Gruenbacher
f3b64b57c0 gfs2: Some whitespace cleanups
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2019-10-30 12:17:04 +01:00
Aliasgar Surti
098b9c1453 gfs2: removed unnecessary semicolon
There is use of unnecessary semicolon after switch case.
Removed the semicolon.

Signed-off-by: Aliasgar Surti <aliasgar.surti500@gmail.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2019-10-30 12:17:04 +01:00
Andrew Price
d5798141fd gfs2: Fix initialisation of args for remount
When gfs2 was converted to use fs_context, the initialisation of the
mount args structure to the currently active args was lost with the
removal of gfs2_remount_fs(), so the checks of the new args on remount
became checks against the default values instead of the current ones.
This caused unexpected remount behaviour and test failures (xfstests
generic/294, generic/306 and generic/452).

Reinstate the args initialisation, this time in gfs2_init_fs_context()
and conditional upon fc->purpose, as that's the only time we get control
before the mount args are parsed in the remount process.

Fixes: 1f52aa08d1 ("gfs2: Convert gfs2 to fs_context")
Signed-off-by: Andrew Price <anprice@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2019-10-30 12:16:53 +01:00
Andrew Price
30aecae86e gfs2: Fix memory leak when gfs2meta's fs_context is freed
gfs2 and gfs2meta share an ->init_fs_context function which allocates an
args structure stored in fc->fs_private. gfs2 registers a ->free
function to free this memory when the fs_context is cleaned up, but
there was not one registered for gfs2meta, causing a leak.

Register a ->free function for gfs2meta. The existing gfs2_fc_free
function does what we need.

Reported-by: syzbot+c2fdfd2b783754878fb6@syzkaller.appspotmail.com
Fixes: 1f52aa08d1 ("gfs2: Convert gfs2 to fs_context")
Signed-off-by: Andrew Price <anprice@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2019-10-24 16:20:43 +02:00
Arnd Bergmann
8d09807048 gfs2: add compat_ioctl support
Out of the four ioctl commands supported on gfs2, only FITRIM
works in compat mode.

Add a proper handler based on the ext4 implementation.

Fixes: 6ddc5c3ddf ("gfs2: getlabel support")
Reviewed-by: Bob Peterson <rpeterso@redhat.com>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2019-10-23 17:23:46 +02:00
Goldwyn Rodrigues
c039b99792 iomap: use a srcmap for a read-modify-write I/O
The srcmap is used to identify where the read is to be performed from.
It is passed to ->iomap_begin, which can fill it in if we need to read
data for partially written blocks from a different location than the
write target.  The srcmap is only supported for buffered writes so far.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
[hch: merged two patches, removed the IOMAP_F_COW flag, use iomap as
      srcmap if not set, adjust length down to srcmap end as well]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
2019-10-21 08:51:59 -07:00
Jan Kara
13ef954445 iomap: Allow forcing of waiting for running DIO in iomap_dio_rw()
Filesystems do not support doing IO as asynchronous in some cases. For
example in case of unaligned writes or in case file size needs to be
extended (e.g. for ext4). Instead of forcing filesystem to wait for AIO
in such cases, add argument to iomap_dio_rw() which makes the function
wait for IO completion. This also results in executing
iomap_dio_complete() inline in iomap_dio_rw() providing its return value
to the caller as for ordinary sync IO.

Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-10-15 08:43:42 -07:00
Linus Torvalds
0b36c9eed2 Merge branch 'work.mount3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull more mount API conversions from Al Viro:
 "Assorted conversions of options parsing to new API.

  gfs2 is probably the most serious one here; the rest is trivial stuff.

  Other things in what used to be #work.mount are going to wait for the
  next cycle (and preferably go via git trees of the filesystems
  involved)"

* 'work.mount3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  gfs2: Convert gfs2 to fs_context
  vfs: Convert spufs to use the new mount API
  vfs: Convert hypfs to use the new mount API
  hypfs: Fix error number left in struct pointer member
  vfs: Convert functionfs to use the new mount API
  vfs: Convert bpf to use the new mount API
2019-09-24 12:33:34 -07:00
Andrew Price
1f52aa08d1 gfs2: Convert gfs2 to fs_context
Convert gfs2 and gfs2meta to fs_context. Removes the duplicated vfs code
from gfs2_mount and instead uses the new vfs_get_block_super() before
switching the ->root to the appropriate dentry.

The mount option parsing has been converted to the new API and error
reporting for invalid options has been made more precise at the same
time.

All of the mount/remount code has been moved into ops_fstype.c

Signed-off-by: Andrew Price <anprice@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: cluster-devel@redhat.com
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-09-18 22:47:05 -04:00
Bob Peterson
f0b444b349 gfs2: clear buf_in_tr when ending a transaction in sweep_bh_for_rgrps
In function sweep_bh_for_rgrps, which is a helper for punch_hole,
it uses variable buf_in_tr to keep track of when it needs to commit
pending block frees on a partial delete that overflows the
transaction created for the delete. The problem is that the
variable was initialized at the start of function sweep_bh_for_rgrps
but it was never cleared, even when starting a new transaction.

This patch reinitializes the variable when the transaction is
ended, so the next transaction starts out with it cleared.

Fixes: d552a2b9b3 ("GFS2: Non-recursive delete")
Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2019-09-17 16:50:50 +02:00
Andreas Gruenbacher
b473bc2dcd gfs2: Improve mmap write vs. truncate consistency
On filesystems with a block size smaller than PAGE_SIZE, page_mkwrite is
called for each memory-mapped page before that page can be written to.
When such a memory-mapped file is truncated down to size x which is not
a multiple of the page size and then back to a larger size, the page
straddling size x can end up with a partial block mapping.  In that
case, make sure to mark that page read-only so that page_mkwrite will be
called before the page can be written to the next time.

(There is no point in marking the page straddling size x read-only when
truncating down as writing to memory beyond the end of the file will
result in SIGBUS instead of growing the file.)

Fixes xfstests generic/029, generic/030 on filesystems with a block size
smaller than PAGE_SIZE.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2019-09-06 22:54:23 +02:00
Bob Peterson
ad26967b9a gfs2: Use async glocks for rename
Because s_vfs_rename_mutex is not cluster-wide, multiple nodes can
reverse the roles of which directories are "old" and which are "new" for
the purposes of rename. This can cause deadlocks where two nodes end up
waiting for each other.

There can be several layers of directory dependencies across many nodes.

This patch fixes the problem by acquiring all gfs2_rename's inode glocks
asychronously and waiting for all glocks to be acquired.  That way all
inodes are locked regardless of the order.

The timeout value for multiple asynchronous glocks is calculated to be
the total of the individual wait times for each glock times two.

Since gfs2_exchange is very similar to gfs2_rename, both functions are
patched in the same way.

A new async glock wait queue, sd_async_glock_wait, keeps a list of
waiters for these events. If gfs2's holder_wake function detects an
async holder, it wakes up any waiters for the event. The waiter only
tests whether any of its requests are still pending.

Since the glocks are sent to dlm asychronously, the wait function needs
to check to see which glocks, if any, were granted.

If a glock is granted by dlm (and therefore held), its minimum hold time
is checked and adjusted as necessary, as other glock grants do.

If the event times out, all glocks held thus far must be dequeued to
resolve any existing deadlocks.  Then, if there are any outstanding
locking requests, we need to loop around and wait for dlm to respond to
those requests too.  After we release all requests, we return -ESTALE to
the caller (vfs rename) which loops around and retries the request.

    Node1           Node2
    ---------       ---------
1.  Enqueue A       Enqueue B
2.  Enqueue B       Enqueue A
3.  A granted
6.                  B granted
7.  Wait for B
8.                  Wait for A
9.                  A times out (since Node 1 holds A)
10.                 Dequeue B (since it was granted)
11.                 Wait for all requests from DLM
12. B Granted (since Node2 released it in step 10)
13. Rename
14. Dequeue A
15.                 DLM Grants A
16.                 Dequeue A (due to the timeout and since we
                    no longer have B held for our task).
17. Dequeue B
18.                 Return -ESTALE to vfs
19.                 VFS retries the operation, goto step 1.

This release-all-locks / acquire-all-locks may slow rename / exchange
down as both nodes struggle in the same way and do the same thing.
However, this will only happen when there is contention for the same
inodes, which ought to be rare.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2019-09-04 20:22:17 +02:00