xfs: calculate correct offset in xfs_scrub_quota_item

It's only used for tracepoints so it's relatively harmless,
but the offset is calculated incorrectly in xfs_scrub_quota_item.

qi_dqperchunk is the nr. of dquots per "chunk" which we have
conveniently *cough* defined to always be 1 FSB.  Therefore
block_offset * qi_dqperchunk == first id in that chunk,
and so offset = id / qi_dqperchunk

id * dqperchunk is ... meaningless.

Fixes-coverity-id: 1423965
Fixes: c2fc338c ("xfs: scrub quota information")
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

diff --git a/fs/xfs/scrub/quota.c b/fs/xfs/scrub/quota.c
index 613def9..3d9037e 100644 (file)
--- a/fs/xfs/scrub/quota.c
+++ b/fs/xfs/scrub/quota.c
@@ -107,7 +107,7 @@ xfs_scrub_quota_item(
        unsigned long long              rcount;
        xfs_ino_t                       fs_icount;
 
-       offset = id * qi->qi_dqperchunk;
+       offset = id / qi->qi_dqperchunk;
 
        /*
         * We fed $id and DQNEXT into the xfs_qm_dqget call, which means