leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

xfs: queue deferred rmap ops for cow staging extent alloc/free in the right order

Browse Source 
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>
This commit is contained in:
Darrick J. Wong 2017-12-07 19:07:03 -08:00
parent 86d692bfad
commit 0525e952dc
1 changed files with 19 additions and 33 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

52
fs/xfs/libxfs/xfs_refcount.c
View File

@ -1488,27 +1488,12 @@ __xfs_refcount_cow_alloc(
xfs_extlen_t aglen,
struct xfs_defer_ops *dfops)
{
int error;
trace_xfs_refcount_cow_increase(rcur->bc_mp, rcur->bc_private.a.agno,
agbno, aglen);
/* Add refcount btree reservation */
error = xfs_refcount_adjust_cow(rcur, agbno, aglen,
return xfs_refcount_adjust_cow(rcur, agbno, aglen,
XFS_REFCOUNT_ADJUST_COW_ALLOC, dfops);
if (error)
return error;
/* Add rmap entry */
if (xfs_sb_version_hasrmapbt(&rcur->bc_mp->m_sb)) {
error = xfs_rmap_alloc_extent(rcur->bc_mp, dfops,
rcur->bc_private.a.agno,
agbno, aglen, XFS_RMAP_OWN_COW);
if (error)
return error;
}
return error;
}
/*
@ -1521,27 +1506,12 @@ __xfs_refcount_cow_free(
xfs_extlen_t aglen,
struct xfs_defer_ops *dfops)
{
int error;
trace_xfs_refcount_cow_decrease(rcur->bc_mp, rcur->bc_private.a.agno,
agbno, aglen);
/* Remove refcount btree reservation */
error = xfs_refcount_adjust_cow(rcur, agbno, aglen,
return xfs_refcount_adjust_cow(rcur, agbno, aglen,
XFS_REFCOUNT_ADJUST_COW_FREE, dfops);
if (error)
return error;
/* Remove rmap entry */
if (xfs_sb_version_hasrmapbt(&rcur->bc_mp->m_sb)) {
error = xfs_rmap_free_extent(rcur->bc_mp, dfops,
rcur->bc_private.a.agno,
agbno, aglen, XFS_RMAP_OWN_COW);
if (error)
return error;
}
return error;
}
/* Record a CoW staging extent in the refcount btree. */
@ -1552,11 +1522,19 @@ xfs_refcount_alloc_cow_extent(
xfs_fsblock_t fsb,
xfs_extlen_t len)
{
int error;
if (!xfs_sb_version_hasreflink(&mp->m_sb))
return 0;
return __xfs_refcount_add(mp, dfops, XFS_REFCOUNT_ALLOC_COW,
error = __xfs_refcount_add(mp, dfops, XFS_REFCOUNT_ALLOC_COW,
fsb, len);
if (error)
return error;
/* Add rmap entry */
return xfs_rmap_alloc_extent(mp, dfops, XFS_FSB_TO_AGNO(mp, fsb),
XFS_FSB_TO_AGBNO(mp, fsb), len, XFS_RMAP_OWN_COW);
}
/* Forget a CoW staging event in the refcount btree. */
@ -1567,9 +1545,17 @@ xfs_refcount_free_cow_extent(
xfs_fsblock_t fsb,
xfs_extlen_t len)
{
int error;
if (!xfs_sb_version_hasreflink(&mp->m_sb))
return 0;
/* Remove rmap entry */
error = xfs_rmap_free_extent(mp, dfops, XFS_FSB_TO_AGNO(mp, fsb),
XFS_FSB_TO_AGBNO(mp, fsb), len, XFS_RMAP_OWN_COW);
if (error)
return error;
return __xfs_refcount_add(mp, dfops, XFS_REFCOUNT_FREE_COW,
fsb, len);
}