[REPOST][RFC][PATCH] ext4: unify each meaning of the offset in ext4_check_dir_entry calling from some functions.

[Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>]

From: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>

"offset" of the error message of ext4_check_dir_entry() might change the
meaning by the caller. There are 2 meanings:
- "File offset"
  called by:
   ext4_readdir, htree_dirblock_to_tree, search_dirblock, ext4_dx_find_entry,
   empty_dir
- "Buffer offset"
  called by:
   add_dirent_to_buf, ext4_delete_entry

The best way to solve this problem is to change the meaning of 
"Buffer offset" into "File offset" but it is not easy.
However, we can solve this problem easily if we unify the meanings into 
"Buffer offset". So, instead of "File Offset" meaning, we add the block number 
information to this message.

--- Examples ---
Original error message:
EXT4-fs error (device loop0): htree_dirblock_to_tree: bad entry in directory \
#12: rec_len is too small for name_len - offset=12288, inode=216, rec_len=12,\
 name_len=11

Error message which is changed by this patch:
EXT4-fs error (device loop0): htree_dirblock_to_tree: bad entry in directory \
#12: rec_len is too small for name_len - block_nr=78:offset=0, inode=216, \
rec_len=12, name_len=11

Signed-off-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
--
 fs/ext4/dir.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff -Nurp linux-2.6.33-rc3.org/fs/ext4/dir.c linux-2.6.33-rc3/fs/ext4/dir.c
--- linux-2.6.33-rc3.org/fs/ext4/dir.c	2010-01-06 09:02:46.000000000 +0900
+++ linux-2.6.33-rc3/fs/ext4/dir.c	2010-01-14 13:13:17.000000000 +0900
@@ -84,9 +84,10 @@ int ext4_check_dir_entry(const char *fun
 
 	if (error_msg != NULL)
 		ext4_error(dir->i_sb, function,
-			"bad entry in directory #%lu: %s - "
+			"bad entry in directory #%lu: %s - block_nr=%llu:"
 			"offset=%u, inode=%u, rec_len=%d, name_len=%d",
-			dir->i_ino, error_msg, offset,
+			dir->i_ino, error_msg, 
+			(u64)bh->b_blocknr, (u32)(offset%bh->b_size),
 			le32_to_cpu(de->inode),
 			rlen, de->name_len);
 	return error_msg == NULL ? 1 : 0;