From 94b941fd7a98cebd6b77b8925c54ef76bbf7473f Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Mon, 29 Jun 2020 14:47:19 -0700 Subject: xfs: only reserve quota blocks if we're mapping into a hole When logging quota block count updates during a reflink operation, we only log the /delta/ of the block count changes to the dquot. Since we now know ahead of time the extent type of both dmap and smap (and that they have the same length), we know that we only need to reserve quota blocks for dmap's blockcount if we're mapping it into a hole. Signed-off-by: Darrick J. Wong Reviewed-by: Brian Foster --- fs/xfs/xfs_reflink.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'fs') diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c index 3073c608216c..35a17ca5b508 100644 --- a/fs/xfs/xfs_reflink.c +++ b/fs/xfs/xfs_reflink.c @@ -1055,7 +1055,9 @@ xfs_reflink_remap_extent( * * If we are mapping a written extent into the file, we need to have * enough quota block count reservation to handle the blocks in that - * extent. + * extent. We log only the delta to the quota block counts, so if the + * extent we're unmapping also has blocks allocated to it, we don't + * need a quota reservation for the extent itself. * * Note that if we're replacing a delalloc reservation with a written * extent, we have to take the full quota reservation because removing @@ -1067,7 +1069,7 @@ xfs_reflink_remap_extent( qres = qdelta = 0; if (smap_real || dmap_written) qres = XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK); - if (dmap_written) + if (!smap_real && dmap_written) qres += dmap->br_blockcount; if (qres > 0) { error = xfs_trans_reserve_quota_nblks(tp, ip, qres, 0, -- cgit v1.2.3