[PATCH v2 2/2] xfs: fix xfs_rmap_has_other_keys usage of ECANCELED

Darrick J. Wong
2020-03-11T16:02:54Z

From: Darrick J. Wong <darrick.wong@oracle.com>

In e7ee96dfb8c26, we converted all ITER_ABORT users to use ECANCELED
instead, but we forgot to teach xfs_rmap_has_other_keys not to return
that magic value to callers. Fix it now by using ECANCELED both to
abort the iteration and to signal that we found another reverse mapping.
This enables us to drop the separate boolean flag.

Fixes: e7ee96dfb8c26 ("xfs: remove all *_ITER_ABORT values")
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
---
v2: fix commit message per hch feedback
---
fs/xfs/libxfs/xfs_rmap.c | 13 ++++++-------
1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_rmap.c b/fs/xfs/libxfs/xfs_rmap.c
index ff9412f113c4..dae1a2bf28eb 100644
--- a/fs/xfs/libxfs/xfs_rmap.c
+++ b/fs/xfs/libxfs/xfs_rmap.c
@@ -2694,7 +2694,6 @@ struct xfs_rmap_key_state {
uint64_t owner;
uint64_t offset;
unsigned int flags;
- bool has_rmap;
};

/* For each rmap given, figure out if it doesn't match the key we want. */
@@ -2709,7 +2708,6 @@ xfs_rmap_has_other_keys_helper(
if (rks->owner == rec->rm_owner && rks->offset == rec->rm_offset &&
((rks->flags & rec->rm_flags) & XFS_RMAP_KEY_FLAGS) == rks->flags)
return 0;
- rks->has_rmap = true;
return -ECANCELED;
}

@@ -2731,7 +2729,7 @@ xfs_rmap_has_other_keys(
int error;

xfs_owner_info_unpack(oinfo, &rks.owner, &rks.offset, &rks.flags);
- rks.has_rmap = false;
+ *has_rmap = false;

low.rm_startblock = bno;
memset(&high, 0xFF, sizeof(high));
@@ -2739,11 +2737,12 @@ xfs_rmap_has_other_keys(

error = xfs_rmap_query_range(cur, &low, &high,
xfs_rmap_has_other_keys_helper, &rks);
- if (error < 0)
- return error;
+ if (error == -ECANCELED) {
+ *has_rmap = true;
+ return 0;
+ }

- *has_rmap = rks.has_rmap;
- return 0;
+ return error;
}

const struct xfs_owner_info XFS_RMAP_OINFO_SKIP_UPDATE = {