I just realized sparse superblocks don't work at all on big endian
(actually, on anything but little endian). The reason is that
sb->u.ext2_sb.s_feature_ro_compat (ie. the kernel structure as opposed to the
ondisk structure member) is being initialized into host CPU order:
sb->u.ext2_sb.s_feature_ro_compat = le32_to_cpu(es->s_feature_ro_compat);
but the code happily applies le32_to_cpu to that value once again.
This patch fixes it.
--- ./fs/ext2/super.c.jj Mon Oct 5 10:19:28 1998
+++ ./fs/ext2/super.c Wed Oct 28 17:10:35 1998
@@ -786,7 +786,7 @@ int ext2_statfs (struct super_block * sb
* superblocks is turned on, then not all groups have
* this.
*/
- if (le32_to_cpu(sb->u.ext2_sb.s_feature_ro_compat) &
+ if (sb->u.ext2_sb.s_feature_ro_compat &
EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER) {
ngroups = 0;
for (i=0 ; i < sb->u.ext2_sb.s_groups_count; i++)
--- ./fs/ext2/balloc.c.jj Tue Oct 27 07:16:17 1998
+++ ./fs/ext2/balloc.c Wed Oct 28 17:14:59 1998
@@ -721,7 +721,7 @@ void ext2_check_blocks_bitmap (struct su
bh = sb->u.ext2_sb.s_block_bitmap[bitmap_nr];
- if (!(le32_to_cpu(sb->u.ext2_sb.s_feature_ro_compat) &
+ if (!(sb->u.ext2_sb.s_feature_ro_compat &
EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER) ||
ext2_group_sparse(i)) {
if (!ext2_test_bit (0, bh->b_data))
Cheers,
Jakub
___________________________________________________________________
Jakub Jelinek | jj@sunsite.mff.cuni.cz | http://sunsite.mff.cuni.cz
Administrator of SunSITE Czech Republic, MFF, Charles University
___________________________________________________________________
Ultralinux - first 64bit OS to take full power of the UltraSparc
Linux version 2.1.126 on a sparc64 machine (498.80 BogoMips).
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