mke2fs: New bitmap and inode table allocation for FLEX_BG
Change the way we allocate bitmaps and inode tables if the FLEX_BG
feature is used at mke2fs time. It places calculates a new offset for
bitmaps and inode table base on the number of groups that the user
wishes to pack together using the new "-G" option. Creating a
filesystem with 64 block groups in a flex group can be done by:
mke2fs -j -I 256 -O flex_bg -G 32 /dev/sdX
Signed-off-by: Jose R. Santos <jrs@us.ibm.com>
Signed-off-by: Valerie Clement <valerie.clement@bull.net>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
diff --git a/lib/ext2fs/initialize.c b/lib/ext2fs/initialize.c
index 8fc1b01..011656f 100644
--- a/lib/ext2fs/initialize.c
+++ b/lib/ext2fs/initialize.c
@@ -159,6 +159,7 @@
set_field(s_first_meta_bg, 0);
set_field(s_raid_stride, 0); /* default stride size: 0 */
set_field(s_raid_stripe_width, 0); /* default stripe width: 0 */
+ set_field(s_log_groups_per_flex, 0);
set_field(s_flags, 0);
if (super->s_feature_incompat & ~EXT2_LIB_FEATURE_INCOMPAT_SUPP) {
retval = EXT2_ET_UNSUPP_FEATURE;
@@ -377,6 +378,10 @@
* Note that although the block bitmap, inode bitmap, and
* inode table have not been allocated (and in fact won't be
* by this routine), they are accounted for nevertheless.
+ *
+ * If FLEX_BG meta-data grouping is used, only account for the
+ * superblock and group descriptors (the inode tables and
+ * bitmaps will be accounted for when allocated).
*/
super->s_free_blocks_count = 0;
csum_flag = EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
@@ -397,6 +402,8 @@
fs->group_desc[i].bg_itable_unused = numblocks;
}
numblocks = ext2fs_reserve_super_and_bgd(fs, i, fs->block_map);
+ if (fs->super->s_log_groups_per_flex)
+ numblocks += 2 + fs->inode_blocks_per_group;
super->s_free_blocks_count += numblocks;
fs->group_desc[i].bg_free_blocks_count = numblocks;