[XFS] Put the correct offset in dirent d_off

The recent filldir regression fix was not putting the correct d_off in
each dirent. This was resulting in incorrect cookies being passed to dmapi
ioctls and the wrong offset appearing in the dirents. readdir was
unaffected as the filp->f_pos was being updated with the correct offset
and this was being written into the last dirent in each buffer. Fix the
XFS code to do the right thing.

SGI-PV: 973746
SGI-Modid: xfs-linux-melb:xfs-kern:30240a

Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
diff --git a/fs/xfs/xfs_dir2_block.c b/fs/xfs/xfs_dir2_block.c
index c171767..a5f4f4f 100644
--- a/fs/xfs/xfs_dir2_block.c
+++ b/fs/xfs/xfs_dir2_block.c
@@ -508,7 +508,7 @@
 			continue;
 
 		cook = xfs_dir2_db_off_to_dataptr(mp, mp->m_dirdatablk,
-						    ptr - (char *)block);
+					    (char *)dep - (char *)block);
 		ino = be64_to_cpu(dep->inumber);
 #if XFS_BIG_INUMS
 		ino += mp->m_inoadd;
@@ -519,9 +519,7 @@
 		 */
 		if (filldir(dirent, dep->name, dep->namelen, cook,
 			    ino, DT_UNKNOWN)) {
-			*offset = xfs_dir2_db_off_to_dataptr(mp,
-					mp->m_dirdatablk,
-					(char *)dep - (char *)block);
+			*offset = cook;
 			xfs_da_brelse(NULL, bp);
 			return 0;
 		}