xfs: go straight to real allocations for direct I/O COW writes
When we allocate COW fork blocks for direct I/O writes we currently first
create a delayed allocation, and then convert it to a real allocation
once we've got the delayed one.
As there is no good reason for that this patch instead makes use call
xfs_bmapi_write from the COW allocation path. The only interesting bits
are a few tweaks the low-level allocator to allow for this, most notably
the need to remove the call to xfs_bmap_extsize_align for the cowextsize
in xfs_bmap_btalloc - for the existing convert case it's a no-op, but
for the direct allocation case it would blow up our block reservation
way beyond what we reserved for the transaction.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
index dcffbb0..1cee514 100644
--- a/fs/xfs/libxfs/xfs_bmap.c
+++ b/fs/xfs/libxfs/xfs_bmap.c
@@ -2895,13 +2895,14 @@ xfs_bmap_add_extent_hole_real(
ASSERT(!isnullstartblock(new->br_startblock));
ASSERT(!bma->cur ||
!(bma->cur->bc_private.b.flags & XFS_BTCUR_BPRV_WASDEL));
- ASSERT(whichfork != XFS_COW_FORK);
XFS_STATS_INC(mp, xs_add_exlist);
state = 0;
if (whichfork == XFS_ATTR_FORK)
state |= BMAP_ATTRFORK;
+ if (whichfork == XFS_COW_FORK)
+ state |= BMAP_COWFORK;
/*
* Check and set flags if this segment has a left neighbor.