xfs: cleanup xchk_dir_rec

Use an offset as the main means for iteration, and only do pointer
arithmetics to find the data/unused entries.

Signed-off-by: Christoph Hellwig <hch@lst.de>
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/dir.c b/fs/xfs/scrub/dir.c
index b474c6f..4f201bd 100644 (file)
--- a/fs/xfs/scrub/dir.c
+++ b/fs/xfs/scrub/dir.c
@@ -190,7 +190,8 @@ xchk_dir_rec(
        struct xfs_dir2_data_entry      *dent;
        struct xfs_buf                  *bp;
        struct xfs_dir2_leaf_entry      *ent;
-       char                            *p, *endp;
+       void                            *endp;
+       unsigned int                    iter_off;
        xfs_ino_t                       ino;
        xfs_dablk_t                     rec_bno;
        xfs_dir2_db_t                   db;
@@ -240,32 +241,31 @@ xchk_dir_rec(
        if (ds->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
                goto out_relse;
 
-       dent = (struct xfs_dir2_data_entry *)(((char *)bp->b_addr) + off);
+       dent = bp->b_addr + off;
 
        /* Make sure we got a real directory entry. */
-       p = (char *)mp->m_dir_inode_ops->data_entry_p(bp->b_addr);
+       iter_off = mp->m_dir_inode_ops->data_entry_offset;
        endp = xfs_dir3_data_endp(mp->m_dir_geo, bp->b_addr);
        if (!endp) {
                xchk_fblock_set_corrupt(ds->sc, XFS_DATA_FORK, rec_bno);
                goto out_relse;
        }
-       while (p < endp) {
-               struct xfs_dir2_data_entry      *dep;
-               struct xfs_dir2_data_unused     *dup;
+       for (;;) {
+               struct xfs_dir2_data_entry      *dep = bp->b_addr + iter_off;
+               struct xfs_dir2_data_unused     *dup = bp->b_addr + iter_off;
+
+               if (iter_off >= endp - bp->b_addr) {
+                       xchk_fblock_set_corrupt(ds->sc, XFS_DATA_FORK, rec_bno);
+                       goto out_relse;
+               }
 
-               dup = (struct xfs_dir2_data_unused *)p;
                if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
-                       p += be16_to_cpu(dup->length);
+                       iter_off += be16_to_cpu(dup->length);
                        continue;
                }
-               dep = (struct xfs_dir2_data_entry *)p;
                if (dep == dent)
                        break;
-               p += mp->m_dir_inode_ops->data_entsize(dep->namelen);
-       }
-       if (p >= endp) {
-               xchk_fblock_set_corrupt(ds->sc, XFS_DATA_FORK, rec_bno);
-               goto out_relse;
+               iter_off += mp->m_dir_inode_ops->data_entsize(dep->namelen);
        }
 
        /* Retrieve the entry, sanity check it, and compare hashes. */