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.h b/include/linux/ext4_fs.h
index 5e2da09..e1103c2 100644
--- a/include/linux/ext4_fs.h
+++ b/include/linux/ext4_fs.h
@@ -830,7 +830,7 @@
{
struct buffer_head *bh;
unsigned long offset;
- unsigned long block_group;
+ ext4_group_t block_group;
};
static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
@@ -855,7 +855,7 @@
/* calculate the first block number of the group */
static inline ext4_fsblk_t
-ext4_group_first_block_no(struct super_block *sb, unsigned long group_no)
+ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
{
return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
@@ -886,8 +886,9 @@
ext4_fsblk_t blocknr);
extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
ext4_fsblk_t blocknr);
-extern int ext4_bg_has_super(struct super_block *sb, int group);
-extern unsigned long ext4_bg_num_gdb(struct super_block *sb, int group);
+extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
+extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
+ ext4_group_t group);
extern ext4_fsblk_t ext4_new_block (handle_t *handle, struct inode *inode,
ext4_fsblk_t goal, int *errp);
extern ext4_fsblk_t ext4_new_blocks (handle_t *handle, struct inode *inode,
@@ -900,7 +901,7 @@
extern ext4_fsblk_t ext4_count_free_blocks (struct super_block *);
extern void ext4_check_blocks_bitmap (struct super_block *);
extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
- unsigned int block_group,
+ ext4_group_t block_group,
struct buffer_head ** bh);
extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
extern void ext4_init_block_alloc_info(struct inode *);
diff --git a/include/linux/ext4_fs_i.h b/include/linux/ext4_fs_i.h
index 6c610b6..2b4e370 100644
--- a/include/linux/ext4_fs_i.h
+++ b/include/linux/ext4_fs_i.h
@@ -30,6 +30,9 @@
/* data type for file logical block number */
typedef __u32 ext4_lblk_t;
+/* data type for block group number */
+typedef unsigned long ext4_group_t;
+
struct ext4_reserve_window {
ext4_fsblk_t _rsv_start; /* First byte reserved */
ext4_fsblk_t _rsv_end; /* Last byte reserved or 0 */
@@ -92,7 +95,7 @@
* place a file's data blocks near its inode block, and new inodes
* near to their parent directory's inode.
*/
- __u32 i_block_group;
+ ext4_group_t i_block_group;
__u32 i_state; /* Dynamic state flags for ext4 */
/* block reservation info */
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 */