Btrfs: Force f_pos to the max when a readdir hits the end of the directory.

Signed-off-by: Chris Mason <chris.mason@oracle.com>

fs/btrfs/inode.c

@@ -1430,7 +1430,7 @@ static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
 			di = (struct btrfs_dir_item *)((char *)di + di_len);
 		}
 	}
-	filp->f_pos++;
+	filp->f_pos = INT_LIMIT(typeof(filp->f_pos));
 nopos:
 	ret = 0;
 err: