Currently metadata writing errors are ignored and not returned from
sys_fsync on ext2 and ext3 filesystems.  That is, at least ext2 and ext3.

Both ext2 and ext3 resort to sync_inode() in their ->sync_inode method,
which in turn calls ->write_inode.  ->write_inode method has void type, and
any IO errors happening inside are lost.

Make ->write_inode return the error code?
Signed-off-by: Andrey Savochkin <saw@saw.sw.com.sg>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>