[PATCH -next] xfs: rmap: only XFS_DATA_FORK field would be set shared

From: Zeng Heng
Date: Tue Sep 06 2022 - 05:29:15 EST


whichfork could be one of the following 3 types:
XFS_DATA_FORK
XFS_ATTR_FORK
XFS_COW_FORK

XFS_COW_FORK is in-memory field instead of on-disk
field, which doesn't need to update in rmap_btree
(already preclude by `xfs_rmap_update_is_needed` ahead).

XFS_ATTR_FORK field doesn't support reflink share.

So here propose to set "whichfork == XFS_DATA_FORK"
as condition.

Signed-off-by: Zeng Heng <zengheng4@xxxxxxxxxx>
---
fs/xfs/libxfs/xfs_rmap.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_rmap.c b/fs/xfs/libxfs/xfs_rmap.c
index 094dfc897ebc..74b34a331cf0 100644
--- a/fs/xfs/libxfs/xfs_rmap.c
+++ b/fs/xfs/libxfs/xfs_rmap.c
@@ -2549,7 +2549,7 @@ xfs_rmap_map_extent(
if (!xfs_rmap_update_is_needed(tp->t_mountp, whichfork))
return;

- if (whichfork != XFS_ATTR_FORK && xfs_is_reflink_inode(ip))
+ if (whichfork == XFS_DATA_FORK && xfs_is_reflink_inode(ip))
type = XFS_RMAP_MAP_SHARED;

__xfs_rmap_add(tp, type, ip->i_ino, whichfork, PREV);
@@ -2568,7 +2568,7 @@ xfs_rmap_unmap_extent(
if (!xfs_rmap_update_is_needed(tp->t_mountp, whichfork))
return;

- if (whichfork != XFS_ATTR_FORK && xfs_is_reflink_inode(ip))
+ if (whichfork == XFS_DATA_FORK && xfs_is_reflink_inode(ip))
type = XFS_RMAP_UNMAP_SHARED;

__xfs_rmap_add(tp, type, ip->i_ino, whichfork, PREV);
@@ -2593,7 +2593,7 @@ xfs_rmap_convert_extent(
if (!xfs_rmap_update_is_needed(mp, whichfork))
return;

- if (whichfork != XFS_ATTR_FORK && xfs_is_reflink_inode(ip))
+ if (whichfork == XFS_DATA_FORK && xfs_is_reflink_inode(ip))
type = XFS_RMAP_CONVERT_SHARED;

__xfs_rmap_add(tp, type, ip->i_ino, whichfork, PREV);
--
2.25.1