From: Toshiyuki Okajima <toshi.okajima@xxxxxxxxxxxxxx>
The dx_map_entry structure doesn't support over 64KB block size by current usage
of its member("offs"). Because "offs" treats an offset of copies of the
ext4_dir_entry_2 structure as is. This member size is 16 bits. But real offset
for over 64KB(256KB) block size needs 18 bits. However, real offset keeps
4 byte boundary, so lower 2 bits is not used.
Therefore, we do the following to fix this limitation:
For "store":
we divide the real offset by 4 and then store this result to "offs"
member.
For "use":
we multiply "offs" member by 4 and then use this result
as real offset.
Signed-off-by: Toshiyuki Okajima <toshi.okajima@xxxxxxxxxxxxxx>
---
fs/ext4/namei.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- linux-2.6.30-rc6/fs/ext4/namei.c.orig 2009-05-26 01:35:09.000000000 +0900
+++ linux-2.6.30-rc6/fs/ext4/namei.c 2009-06-06 00:05:51.000000000 +0900
@@ -750,7 +750,7 @@ static int dx_make_map(struct ext4_dir_e
ext4fs_dirhash(de->name, de->name_len, &h);
map_tail--;
map_tail->hash = h.hash;
- map_tail->offs = (u16) ((char *) de - base);
+ map_tail->offs = ((char *) de - base)>>2;
map_tail->size = le16_to_cpu(de->rec_len);
count++;
cond_resched();
@@ -1148,7 +1148,8 @@ dx_move_dirents(char *from, char *to, st
unsigned rec_len = 0;
while (count--) {
- struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *) (from + map->offs);
+ struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *)
+ (from + (map->offs<<2));
rec_len = EXT4_DIR_REC_LEN(de->name_len);
memcpy (to, de, rec_len);
((struct ext4_dir_entry_2 *) to)->rec_len =
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
