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>

1 files changed, 1 insertions, 1 deletions

diff --git a/include/linux/ext4_fs_sb.h b/include/linux/ext4_fs_sb.h
index b40e827cd495..f15821c5e4c4 100644
--- a/include/linux/ext4_fs_sb.h
+++ b/include/linux/ext4_fs_sb.h
@@ -35,7 +35,7 @@ struct ext4_sb_info {
         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 */