From: Brian Foster bfoster@redhat.com
[ Upstream commit ad90bb585c45917b6c1bb01c812fba337e689362 ]
XFS started using the perag metadata reservation pool for free inode btree blocks in commit 76d771b4cbe33 ("xfs: use per-AG reservations for the finobt"). To handle backwards compatibility, finobt blocks are accounted against the pool so long as the full reservation is available at mount time. Otherwise the ->m_inotbt_nores flag is set and the filesystem falls back to the traditional per-transaction finobt reservation.
This commit has two problems:
- finobt blocks are always accounted against the metadata reservation on allocation, regardless of ->m_inotbt_nores state - finobt blocks are never returned to the reservation pool on free
The first problem affects reflink+finobt filesystems where the full finobt reservation is not available at mount time. finobt blocks are essentially stolen from the reflink reservation, putting refcountbt management at risk of allocation failure. The second problem is an unconditional leak of metadata reservation whenever finobt is enabled.
Update the finobt block allocation callouts to consider ->m_inotbt_nores and account blocks appropriately. Blocks should be consistently accounted against the metadata pool when ->m_inotbt_nores is false and otherwise tagged as RESV_NONE.
Signed-off-by: Brian Foster bfoster@redhat.com Reviewed-by: Darrick J. Wong darrick.wong@oracle.com Signed-off-by: Darrick J. Wong darrick.wong@oracle.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com --- fs/xfs/libxfs/xfs_ialloc_btree.c | 29 +++++++++++++++++++++++++---- 1 file changed, 25 insertions(+), 4 deletions(-)
diff --git a/fs/xfs/libxfs/xfs_ialloc_btree.c b/fs/xfs/libxfs/xfs_ialloc_btree.c index 317caba9faa6..af3c20821a48 100644 --- a/fs/xfs/libxfs/xfs_ialloc_btree.c +++ b/fs/xfs/libxfs/xfs_ialloc_btree.c @@ -141,21 +141,42 @@ xfs_finobt_alloc_block( union xfs_btree_ptr *new, int *stat) { + if (cur->bc_mp->m_inotbt_nores) + return xfs_inobt_alloc_block(cur, start, new, stat); return __xfs_inobt_alloc_block(cur, start, new, stat, XFS_AG_RESV_METADATA); }
STATIC int -xfs_inobt_free_block( +__xfs_inobt_free_block( struct xfs_btree_cur *cur, - struct xfs_buf *bp) + struct xfs_buf *bp, + enum xfs_ag_resv_type resv) { struct xfs_owner_info oinfo;
xfs_rmap_ag_owner(&oinfo, XFS_RMAP_OWN_INOBT); return xfs_free_extent(cur->bc_tp, XFS_DADDR_TO_FSB(cur->bc_mp, XFS_BUF_ADDR(bp)), 1, - &oinfo, XFS_AG_RESV_NONE); + &oinfo, resv); +} + +STATIC int +xfs_inobt_free_block( + struct xfs_btree_cur *cur, + struct xfs_buf *bp) +{ + return __xfs_inobt_free_block(cur, bp, XFS_AG_RESV_NONE); +} + +STATIC int +xfs_finobt_free_block( + struct xfs_btree_cur *cur, + struct xfs_buf *bp) +{ + if (cur->bc_mp->m_inotbt_nores) + return xfs_inobt_free_block(cur, bp); + return __xfs_inobt_free_block(cur, bp, XFS_AG_RESV_METADATA); }
STATIC int @@ -372,7 +393,7 @@ static const struct xfs_btree_ops xfs_finobt_ops = { .dup_cursor = xfs_inobt_dup_cursor, .set_root = xfs_finobt_set_root, .alloc_block = xfs_finobt_alloc_block, - .free_block = xfs_inobt_free_block, + .free_block = xfs_finobt_free_block, .get_minrecs = xfs_inobt_get_minrecs, .get_maxrecs = xfs_inobt_get_maxrecs, .init_key_from_rec = xfs_inobt_init_key_from_rec,