From 4c2c947f4888454a91f04a5df26cf8303453e089 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Mon, 29 Jun 2020 14:47:18 -0700 Subject: xfs: fix reflink quota reservation accounting error [ Upstream commit 83895227aba1ade33e81f586aa7b6b1e143096a5 ] Quota reservations are supposed to account for the blocks that might be allocated due to a bmap btree split. Reflink doesn't do this, so fix this to make the quota accounting more accurate before we start rearranging things. Fixes: 862bb360ef56 ("xfs: reflink extents from one file to another") Signed-off-by: Darrick J. Wong Reviewed-by: Brian Foster Signed-off-by: Sasha Levin --- fs/xfs/xfs_reflink.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) (limited to 'fs/xfs') diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c index 6622652a85a8..0b159a79a17c 100644 --- a/fs/xfs/xfs_reflink.c +++ b/fs/xfs/xfs_reflink.c @@ -1010,6 +1010,7 @@ xfs_reflink_remap_extent( xfs_filblks_t rlen; xfs_filblks_t unmap_len; xfs_off_t newlen; + int64_t qres; int error; unmap_len = irec->br_startoff + irec->br_blockcount - destoff; @@ -1032,13 +1033,19 @@ xfs_reflink_remap_extent( xfs_ilock(ip, XFS_ILOCK_EXCL); xfs_trans_ijoin(tp, ip, 0); - /* If we're not just clearing space, then do we have enough quota? */ - if (real_extent) { - error = xfs_trans_reserve_quota_nblks(tp, ip, - irec->br_blockcount, 0, XFS_QMOPT_RES_REGBLKS); - if (error) - goto out_cancel; - } + /* + * Reserve quota for this operation. We don't know if the first unmap + * in the dest file will cause a bmap btree split, so we always reserve + * at least enough blocks for that split. If the extent being mapped + * in is written, we need to reserve quota for that too. + */ + qres = XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK); + if (real_extent) + qres += irec->br_blockcount; + error = xfs_trans_reserve_quota_nblks(tp, ip, qres, 0, + XFS_QMOPT_RES_REGBLKS); + if (error) + goto out_cancel; trace_xfs_reflink_remap(ip, irec->br_startoff, irec->br_blockcount, irec->br_startblock); -- cgit v1.2.3