From 2ba090d521c5e09f32316c179d25bb6f699d3568 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 7 Aug 2018 10:57:12 -0700 Subject: xfs: use WRITE_ONCE to update if_seq This adds ordering of the updates and makes sure we always see the if_seq update before the extent tree is modified. Signed-off-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/xfs/xfs_iomap.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'fs/xfs/xfs_iomap.c') diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c index 3282575e2df4..6320aca39f39 100644 --- a/fs/xfs/xfs_iomap.c +++ b/fs/xfs/xfs_iomap.c @@ -655,6 +655,7 @@ xfs_iomap_write_allocate( unsigned int *cow_seq) { xfs_mount_t *mp = ip->i_mount; + struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, whichfork); xfs_fileoff_t offset_fsb, last_block; xfs_fileoff_t end_fsb, map_start_fsb; xfs_filblks_t count_fsb; @@ -768,7 +769,7 @@ xfs_iomap_write_allocate( goto error0; if (whichfork == XFS_COW_FORK) - *cow_seq = XFS_IFORK_PTR(ip, whichfork)->if_seq; + *cow_seq = READ_ONCE(ifp->if_seq); xfs_iunlock(ip, XFS_ILOCK_EXCL); } -- cgit v1.2.1