linux/fs/xfs/xfs_attr_inactive.c
Darrick J. Wong 54027a4993 xfs: fix uninitialized variable in xfs_attr3_leaf_inactive
Dan Carpenter pointed out that error is uninitialized.  While there
never should be an attr leaf block with zero entries, let's not leave
that logic bomb there.

Fixes: 0bb9d159bd ("xfs: streamline xfs_attr3_leaf_inactive")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
2020-01-23 16:11:32 -08:00

396 lines
9.7 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2000-2005 Silicon Graphics, Inc.
* Copyright (c) 2013 Red Hat, Inc.
* All Rights Reserved.
*/
#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_bit.h"
#include "xfs_mount.h"
#include "xfs_da_format.h"
#include "xfs_da_btree.h"
#include "xfs_inode.h"
#include "xfs_attr_remote.h"
#include "xfs_trans.h"
#include "xfs_bmap.h"
#include "xfs_attr.h"
#include "xfs_attr_leaf.h"
#include "xfs_quota.h"
#include "xfs_dir2.h"
#include "xfs_error.h"
/*
* Invalidate any incore buffers associated with this remote attribute value
* extent. We never log remote attribute value buffers, which means that they
* won't be attached to a transaction and are therefore safe to mark stale.
* The actual bunmapi will be taken care of later.
*/
STATIC int
xfs_attr3_rmt_stale(
struct xfs_inode *dp,
xfs_dablk_t blkno,
int blkcnt)
{
struct xfs_bmbt_irec map;
int nmap;
int error;
/*
* Roll through the "value", invalidating the attribute value's
* blocks.
*/
while (blkcnt > 0) {
/*
* Try to remember where we decided to put the value.
*/
nmap = 1;
error = xfs_bmapi_read(dp, (xfs_fileoff_t)blkno, blkcnt,
&map, &nmap, XFS_BMAPI_ATTRFORK);
if (error)
return error;
if (XFS_IS_CORRUPT(dp->i_mount, nmap != 1))
return -EFSCORRUPTED;
/*
* Mark any incore buffers for the remote value as stale. We
* never log remote attr value buffers, so the buffer should be
* easy to kill.
*/
error = xfs_attr_rmtval_stale(dp, &map, 0);
if (error)
return error;
blkno += map.br_blockcount;
blkcnt -= map.br_blockcount;
}
return 0;
}
/*
* Invalidate all of the "remote" value regions pointed to by a particular
* leaf block.
* Note that we must release the lock on the buffer so that we are not
* caught holding something that the logging code wants to flush to disk.
*/
STATIC int
xfs_attr3_leaf_inactive(
struct xfs_trans **trans,
struct xfs_inode *dp,
struct xfs_buf *bp)
{
struct xfs_attr3_icleaf_hdr ichdr;
struct xfs_mount *mp = bp->b_mount;
struct xfs_attr_leafblock *leaf = bp->b_addr;
struct xfs_attr_leaf_entry *entry;
struct xfs_attr_leaf_name_remote *name_rmt;
int error = 0;
int i;
xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, leaf);
/*
* Find the remote value extents for this leaf and invalidate their
* incore buffers.
*/
entry = xfs_attr3_leaf_entryp(leaf);
for (i = 0; i < ichdr.count; entry++, i++) {
int blkcnt;
if (!entry->nameidx || (entry->flags & XFS_ATTR_LOCAL))
continue;
name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
if (!name_rmt->valueblk)
continue;
blkcnt = xfs_attr3_rmt_blocks(dp->i_mount,
be32_to_cpu(name_rmt->valuelen));
error = xfs_attr3_rmt_stale(dp,
be32_to_cpu(name_rmt->valueblk), blkcnt);
if (error)
goto err;
}
xfs_trans_brelse(*trans, bp);
err:
return error;
}
/*
* Recurse (gasp!) through the attribute nodes until we find leaves.
* We're doing a depth-first traversal in order to invalidate everything.
*/
STATIC int
xfs_attr3_node_inactive(
struct xfs_trans **trans,
struct xfs_inode *dp,
struct xfs_buf *bp,
int level)
{
struct xfs_mount *mp = dp->i_mount;
struct xfs_da_blkinfo *info;
xfs_dablk_t child_fsb;
xfs_daddr_t parent_blkno, child_blkno;
struct xfs_buf *child_bp;
struct xfs_da3_icnode_hdr ichdr;
int error, i;
/*
* Since this code is recursive (gasp!) we must protect ourselves.
*/
if (level > XFS_DA_NODE_MAXDEPTH) {
xfs_trans_brelse(*trans, bp); /* no locks for later trans */
xfs_buf_corruption_error(bp);
return -EFSCORRUPTED;
}
xfs_da3_node_hdr_from_disk(dp->i_mount, &ichdr, bp->b_addr);
parent_blkno = bp->b_bn;
if (!ichdr.count) {
xfs_trans_brelse(*trans, bp);
return 0;
}
child_fsb = be32_to_cpu(ichdr.btree[0].before);
xfs_trans_brelse(*trans, bp); /* no locks for later trans */
/*
* If this is the node level just above the leaves, simply loop
* over the leaves removing all of them. If this is higher up
* in the tree, recurse downward.
*/
for (i = 0; i < ichdr.count; i++) {
/*
* Read the subsidiary block to see what we have to work with.
* Don't do this in a transaction. This is a depth-first
* traversal of the tree so we may deal with many blocks
* before we come back to this one.
*/
error = xfs_da3_node_read(*trans, dp, child_fsb, &child_bp,
XFS_ATTR_FORK);
if (error)
return error;
/* save for re-read later */
child_blkno = XFS_BUF_ADDR(child_bp);
/*
* Invalidate the subtree, however we have to.
*/
info = child_bp->b_addr;
switch (info->magic) {
case cpu_to_be16(XFS_DA_NODE_MAGIC):
case cpu_to_be16(XFS_DA3_NODE_MAGIC):
error = xfs_attr3_node_inactive(trans, dp, child_bp,
level + 1);
break;
case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
error = xfs_attr3_leaf_inactive(trans, dp, child_bp);
break;
default:
xfs_buf_corruption_error(child_bp);
xfs_trans_brelse(*trans, child_bp);
error = -EFSCORRUPTED;
break;
}
if (error)
return error;
/*
* Remove the subsidiary block from the cache and from the log.
*/
child_bp = xfs_trans_get_buf(*trans, mp->m_ddev_targp,
child_blkno,
XFS_FSB_TO_BB(mp, mp->m_attr_geo->fsbcount), 0);
if (!child_bp)
return -EIO;
error = bp->b_error;
if (error) {
xfs_trans_brelse(*trans, child_bp);
return error;
}
xfs_trans_binval(*trans, child_bp);
/*
* If we're not done, re-read the parent to get the next
* child block number.
*/
if (i + 1 < ichdr.count) {
struct xfs_da3_icnode_hdr phdr;
error = xfs_da3_node_read_mapped(*trans, dp,
parent_blkno, &bp, XFS_ATTR_FORK);
if (error)
return error;
xfs_da3_node_hdr_from_disk(dp->i_mount, &phdr,
bp->b_addr);
child_fsb = be32_to_cpu(phdr.btree[i + 1].before);
xfs_trans_brelse(*trans, bp);
}
/*
* Atomically commit the whole invalidate stuff.
*/
error = xfs_trans_roll_inode(trans, dp);
if (error)
return error;
}
return 0;
}
/*
* Indiscriminately delete the entire attribute fork
*
* Recurse (gasp!) through the attribute nodes until we find leaves.
* We're doing a depth-first traversal in order to invalidate everything.
*/
static int
xfs_attr3_root_inactive(
struct xfs_trans **trans,
struct xfs_inode *dp)
{
struct xfs_mount *mp = dp->i_mount;
struct xfs_da_blkinfo *info;
struct xfs_buf *bp;
xfs_daddr_t blkno;
int error;
/*
* Read block 0 to see what we have to work with.
* We only get here if we have extents, since we remove
* the extents in reverse order the extent containing
* block 0 must still be there.
*/
error = xfs_da3_node_read(*trans, dp, 0, &bp, XFS_ATTR_FORK);
if (error)
return error;
blkno = bp->b_bn;
/*
* Invalidate the tree, even if the "tree" is only a single leaf block.
* This is a depth-first traversal!
*/
info = bp->b_addr;
switch (info->magic) {
case cpu_to_be16(XFS_DA_NODE_MAGIC):
case cpu_to_be16(XFS_DA3_NODE_MAGIC):
error = xfs_attr3_node_inactive(trans, dp, bp, 1);
break;
case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
error = xfs_attr3_leaf_inactive(trans, dp, bp);
break;
default:
error = -EFSCORRUPTED;
xfs_buf_corruption_error(bp);
xfs_trans_brelse(*trans, bp);
break;
}
if (error)
return error;
/*
* Invalidate the incore copy of the root block.
*/
bp = xfs_trans_get_buf(*trans, mp->m_ddev_targp, blkno,
XFS_FSB_TO_BB(mp, mp->m_attr_geo->fsbcount), 0);
if (!bp)
return -EIO;
error = bp->b_error;
if (error) {
xfs_trans_brelse(*trans, bp);
return error;
}
xfs_trans_binval(*trans, bp); /* remove from cache */
/*
* Commit the invalidate and start the next transaction.
*/
error = xfs_trans_roll_inode(trans, dp);
return error;
}
/*
* xfs_attr_inactive kills all traces of an attribute fork on an inode. It
* removes both the on-disk and in-memory inode fork. Note that this also has to
* handle the condition of inodes without attributes but with an attribute fork
* configured, so we can't use xfs_inode_hasattr() here.
*
* The in-memory attribute fork is removed even on error.
*/
int
xfs_attr_inactive(
struct xfs_inode *dp)
{
struct xfs_trans *trans;
struct xfs_mount *mp;
int lock_mode = XFS_ILOCK_SHARED;
int error = 0;
mp = dp->i_mount;
ASSERT(! XFS_NOT_DQATTACHED(mp, dp));
xfs_ilock(dp, lock_mode);
if (!XFS_IFORK_Q(dp))
goto out_destroy_fork;
xfs_iunlock(dp, lock_mode);
lock_mode = 0;
error = xfs_trans_alloc(mp, &M_RES(mp)->tr_attrinval, 0, 0, 0, &trans);
if (error)
goto out_destroy_fork;
lock_mode = XFS_ILOCK_EXCL;
xfs_ilock(dp, lock_mode);
if (!XFS_IFORK_Q(dp))
goto out_cancel;
/*
* No need to make quota reservations here. We expect to release some
* blocks, not allocate, in the common case.
*/
xfs_trans_ijoin(trans, dp, 0);
/*
* Invalidate and truncate the attribute fork extents. Make sure the
* fork actually has attributes as otherwise the invalidation has no
* blocks to read and returns an error. In this case, just do the fork
* removal below.
*/
if (xfs_inode_hasattr(dp) &&
dp->i_d.di_aformat != XFS_DINODE_FMT_LOCAL) {
error = xfs_attr3_root_inactive(&trans, dp);
if (error)
goto out_cancel;
error = xfs_itruncate_extents(&trans, dp, XFS_ATTR_FORK, 0);
if (error)
goto out_cancel;
}
/* Reset the attribute fork - this also destroys the in-core fork */
xfs_attr_fork_remove(dp, trans);
error = xfs_trans_commit(trans);
xfs_iunlock(dp, lock_mode);
return error;
out_cancel:
xfs_trans_cancel(trans);
out_destroy_fork:
/* kill the in-core attr fork before we drop the inode lock */
if (dp->i_afp)
xfs_idestroy_fork(dp, XFS_ATTR_FORK);
if (lock_mode)
xfs_iunlock(dp, lock_mode);
return error;
}