ext4: add ext4_group_t, and change all group variables to this type.
In many places variables for block group are of type int, which limits the
maximum number of block groups to 2^31. Each block group can have up to
2^15 blocks, with a 4K block size, and the max filesystem size is limited to
2^31 * (2^15 * 2^12) = 2^58 -- or 256 PB
This patch introduces a new type ext4_group_t, of type unsigned long, to
represent block group numbers in ext4.
All occurrences of block group variables are converted to type ext4_group_t.
Signed-off-by: Avantika Mathur <mathur@us.ibm.com>
diff --git a/include/linux/ext4_fs_sb.h b/include/linux/ext4_fs_sb.h
index b40e827..f15821c 100644
--- a/include/linux/ext4_fs_sb.h
+++ b/include/linux/ext4_fs_sb.h
@@ -35,7 +35,7 @@
unsigned long s_itb_per_group; /* Number of inode table blocks per group */
unsigned long s_gdb_count; /* Number of group descriptor blocks */
unsigned long s_desc_per_block; /* Number of group descriptors per block */
- unsigned long s_groups_count; /* Number of groups in the fs */
+ ext4_group_t s_groups_count; /* Number of groups in the fs */
unsigned long s_overhead_last; /* Last calculated overhead */
unsigned long s_blocks_last; /* Last seen block count */
struct buffer_head * s_sbh; /* Buffer containing the super block */