[PATCH 07/10] xfs: fix space reservation in xfs_bmbt_alloc_block

Christoph Hellwig
2017-04-13T08:05:51Z

minleft counts the number of blocks that need to be available after the
current allocation has been completed. As the total allocation should not
be more than the transaction reservation we need to subtract the
allocation length. In addition we need to subtract the already used
transaction reservation, for that use the new xfs_trans_blk_res helper.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
fs/xfs/libxfs/xfs_bmap_btree.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_bmap_btree.c b/fs/xfs/libxfs/xfs_bmap_btree.c
index ce41dd5fbb34..153c969febd4 100644
--- a/fs/xfs/libxfs/xfs_bmap_btree.c
+++ b/fs/xfs/libxfs/xfs_bmap_btree.c
@@ -442,6 +442,7 @@ xfs_bmbt_alloc_block(
args.mp = cur->bc_mp;
args.fsbno = cur->bc_private.b.firstblock;
args.firstblock = args.fsbno;
+ args.minlen = args.maxlen = args.prod = 1;
xfs_rmap_ino_bmbt_owner(&args.oinfo, cur->bc_private.b.ip->i_ino,
cur->bc_private.b.whichfork);

@@ -459,14 +460,14 @@ xfs_bmbt_alloc_block(
* reservation amount is insufficient then we may fail a
* block allocation here and corrupt the filesystem.
*/
- args.minleft = args.tp->t_blk_res;
+ if (xfs_trans_blk_res(args.tp))
+ args.minleft = xfs_trans_blk_res(args.tp) - args.maxlen;
} else if (cur->bc_private.b.dfops->dop_low) {
args.type = XFS_ALLOCTYPE_START_BNO;
} else {
args.type = XFS_ALLOCTYPE_NEAR_BNO;
}

- args.minlen = args.maxlen = args.prod = 1;
args.wasdel = cur->bc_private.b.flags & XFS_BTCUR_BPRV_WASDEL;
if (!args.wasdel && args.tp->t_blk_res == 0) {
error = -ENOSPC;
--
2.11.0