From d5753847b216db0e553e8065aa825cfe497ad143 Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Sat, 11 Feb 2023 04:09:06 +1100 Subject: xfs: block reservation too large for minleft allocation When we enter xfs_bmbt_alloc_block() without having first allocated a data extent (i.e. tp->t_firstblock == NULLFSBLOCK) because we are doing something like unwritten extent conversion, the transaction block reservation is used as the minleft value. This works for operations like unwritten extent conversion, but it assumes that the block reservation is only for a BMBT split. THis is not always true, and sometimes results in larger than necessary minleft values being set. We only actually need enough space for a btree split, something we already handle correctly in xfs_bmapi_write() via the xfs_bmapi_minleft() calculation. We should use xfs_bmapi_minleft() in xfs_bmbt_alloc_block() to calculate the number of blocks a BMBT split on this inode is going to require, not use the transaction block reservation that contains the maximum number of blocks this transaction may consume in it... Signed-off-by: Dave Chinner Reviewed-by: Allison Henderson Reviewed-by: Darrick J. Wong --- fs/xfs/libxfs/xfs_bmap.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'fs/xfs/libxfs/xfs_bmap.h') diff --git a/fs/xfs/libxfs/xfs_bmap.h b/fs/xfs/libxfs/xfs_bmap.h index 01c2df35c3e3..524912f276f8 100644 --- a/fs/xfs/libxfs/xfs_bmap.h +++ b/fs/xfs/libxfs/xfs_bmap.h @@ -220,6 +220,8 @@ int xfs_bmap_add_extent_unwritten_real(struct xfs_trans *tp, struct xfs_inode *ip, int whichfork, struct xfs_iext_cursor *icur, struct xfs_btree_cur **curp, struct xfs_bmbt_irec *new, int *logflagsp); +xfs_extlen_t xfs_bmapi_minleft(struct xfs_trans *tp, struct xfs_inode *ip, + int fork); enum xfs_bmap_intent_type { XFS_BMAP_MAP = 1, -- cgit v1.2.3-73-gaa49b