UBIFS: small amendments in the LEB scanning code

This patch fixes few minor things I've spotted while going through
code:

1. Better document return codes
2. If 'ubifs_scan_a_node()' returns some thing we do not expect,
   treat this as an error.
3. Try to do recovery only when 'ubifs_scan()' returns %-EUCLEAN,
   not on any error.
4. If empty space starts at a non-aligned address, print a message.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Reviewed-by: Adrian Hunter <Adrian.Hunter@nokia.com>

1 files changed, 4 insertions, 3 deletions

diff --git a/fs/ubifs/recovery.c b/fs/ubifs/recovery.c
index 805605250f12..093a1ecb700f 100644
--- a/fs/ubifs/recovery.c
+++ b/fs/ubifs/recovery.c
@@ -543,8 +543,8 @@ static int drop_incomplete_group(struct ubifs_scan_leb *sleb, int *offs)
  *
  * This function does a scan of a LEB, but caters for errors that might have
  * been caused by the unclean unmount from which we are attempting to recover.
- *
- * This function returns %0 on success and a negative error code on failure.
+ * Returns %0 in case of success, %-EUCLEAN if an unrecoverable corruption is
+ * found, and a negative error code in case of failure.
  */
 struct ubifs_scan_leb *ubifs_recover_leb(struct ubifs_info *c, int lnum,
                                          int offs, void *sbuf, int grouped)
@@ -643,7 +643,8 @@ struct ubifs_scan_leb *ubifs_recover_leb(struct ubifs_info *c, int lnum,
                         goto corrupted;
                 default:
                         dbg_err("unknown");
-                        goto corrupted;
+                        err = -EINVAL;
+                        goto error;
                 }
         }