[PATCH] ext4 64 bit divide fix

With CONFIG_LBD=n, sector_div() expands to a plain old divide.  But ext4 is
_not_ passing in a sector_t as the first argument, so...

fs/built-in.o: In function `ext4_get_group_no_and_offset':
fs/ext4/balloc.c:39: undefined reference to `__umoddi3'
fs/ext4/balloc.c:41: undefined reference to `__udivdi3'
fs/built-in.o: In function `find_group_orlov':
fs/ext4/ialloc.c:278: undefined reference to `__udivdi3'
fs/built-in.o: In function `ext4_fill_super':
fs/ext4/super.c:1488: undefined reference to `__udivdi3'
fs/ext4/super.c:1488: undefined reference to `__umoddi3'
fs/ext4/super.c:1594: undefined reference to `__udivdi3'
fs/ext4/super.c:1601: undefined reference to `__umoddi3'

Fix that up by calling do_div() directly.

Also cast the arg to u64.  do_div() is only defined on u64, and ext4_fsblk_t
is supposed to be opaque.

Note especially the changes to find_group_orlov().  It was attempting to do

	do_div(int, unsigned long long);

which is royally screwed up.  Switched it to plain old divide.

Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c
index 402475a..5d45582 100644
--- a/fs/ext4/balloc.c
+++ b/fs/ext4/balloc.c
@@ -34,7 +34,7 @@
 	ext4_grpblk_t offset;
 
         blocknr = blocknr - le32_to_cpu(es->s_first_data_block);
-        offset = sector_div(blocknr, EXT4_BLOCKS_PER_GROUP(sb));
+	offset = do_div(blocknr, EXT4_BLOCKS_PER_GROUP(sb));
 	if (offsetp)
 		*offsetp = offset;
 	if (blockgrpp)