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>

9 files changed, 91 insertions, 87 deletions

diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c
index 71ee95e534fd..9568a57c607c 100644
--- a/fs/ext4/balloc.c
+++ b/fs/ext4/balloc.c
@@ -29,7 +29,7 @@
  * Calculate the block group number and offset, given a block number
  */
 void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
-                unsigned long *blockgrpp, ext4_grpblk_t *offsetp)
+                ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp)
 {
         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
         ext4_grpblk_t offset;
@@ -46,7 +46,7 @@ void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
 /* Initializes an uninitialized block bitmap if given, and returns the
  * number of blocks free in the group. */
 unsigned ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh,
-                                int block_group, struct ext4_group_desc *gdp)
+                 ext4_group_t block_group, struct ext4_group_desc *gdp)
 {
         unsigned long start;
         int bit, bit_max;
@@ -60,7 +60,7 @@ unsigned ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh,
                  * essentially implementing a per-group read-only flag. */
                 if (!ext4_group_desc_csum_verify(sbi, block_group, gdp)) {
                         ext4_error(sb, __FUNCTION__,
-                                   "Checksum bad for group %u\n", block_group);
+                                  "Checksum bad for group %lu\n", block_group);
                         gdp->bg_free_blocks_count = 0;
                         gdp->bg_free_inodes_count = 0;
                         gdp->bg_itable_unused = 0;
@@ -153,7 +153,7 @@ unsigned ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh,
  *                      group descriptor
  */
 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)
 {
         unsigned long group_desc;
@@ -164,7 +164,7 @@ struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
         if (block_group >= sbi->s_groups_count) {
                 ext4_error (sb, "ext4_get_group_desc",
                             "block_group >= groups_count - "
-                            "block_group = %d, groups_count = %lu",
+                            "block_group = %lu, groups_count = %lu",
                             block_group, sbi->s_groups_count);
 
                 return NULL;
@@ -176,7 +176,7 @@ struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
         if (!sbi->s_group_desc[group_desc]) {
                 ext4_error (sb, "ext4_get_group_desc",
                             "Group descriptor not loaded - "
-                            "block_group = %d, group_desc = %lu, desc = %lu",
+                            "block_group = %lu, group_desc = %lu, desc = %lu",
                              block_group, group_desc, offset);
                 return NULL;
         }
@@ -200,7 +200,7 @@ struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
  * Return buffer_head on success or NULL in case of failure.
  */
 struct buffer_head *
-read_block_bitmap(struct super_block *sb, unsigned int block_group)
+read_block_bitmap(struct super_block *sb, ext4_group_t block_group)
 {
         struct ext4_group_desc * desc;
         struct buffer_head * bh = NULL;
@@ -227,7 +227,7 @@ read_block_bitmap(struct super_block *sb, unsigned int block_group)
         if (!bh)
                 ext4_error (sb, __FUNCTION__,
                             "Cannot read block bitmap - "
-                            "block_group = %d, block_bitmap = %llu",
+                            "block_group = %lu, block_bitmap = %llu",
                             block_group, bitmap_blk);
         return bh;
 }
@@ -320,7 +320,7 @@ restart:
  */
 static int
 goal_in_my_reservation(struct ext4_reserve_window *rsv, ext4_grpblk_t grp_goal,
-                        unsigned int group, struct super_block * sb)
+                        ext4_group_t group, struct super_block *sb)
 {
         ext4_fsblk_t group_first_block, group_last_block;
 
@@ -540,7 +540,7 @@ void ext4_free_blocks_sb(handle_t *handle, struct super_block *sb,
 {
         struct buffer_head *bitmap_bh = NULL;
         struct buffer_head *gd_bh;
-        unsigned long block_group;
+        ext4_group_t block_group;
         ext4_grpblk_t bit;
         unsigned long i;
         unsigned long overflow;
@@ -920,9 +920,10 @@ claim_block(spinlock_t *lock, ext4_grpblk_t block, struct buffer_head *bh)
  * ext4_journal_release_buffer(), else we'll run out of credits.
  */
 static ext4_grpblk_t
-ext4_try_to_allocate(struct super_block *sb, handle_t *handle, int group,
-                        struct buffer_head *bitmap_bh, ext4_grpblk_t grp_goal,
-                        unsigned long *count, struct ext4_reserve_window *my_rsv)
+ext4_try_to_allocate(struct super_block *sb, handle_t *handle,
+                        ext4_group_t group, struct buffer_head *bitmap_bh,
+                        ext4_grpblk_t grp_goal, unsigned long *count,
+                        struct ext4_reserve_window *my_rsv)
 {
         ext4_fsblk_t group_first_block;
         ext4_grpblk_t start, end;
@@ -1156,7 +1157,7 @@ static int find_next_reservable_window(
  */
 static int alloc_new_reservation(struct ext4_reserve_window_node *my_rsv,
                 ext4_grpblk_t grp_goal, struct super_block *sb,
-                unsigned int group, struct buffer_head *bitmap_bh)
+                ext4_group_t group, struct buffer_head *bitmap_bh)
 {
         struct ext4_reserve_window_node *search_head;
         ext4_fsblk_t group_first_block, group_end_block, start_block;
@@ -1354,7 +1355,7 @@ static void try_to_extend_reservation(struct ext4_reserve_window_node *my_rsv,
  */
 static ext4_grpblk_t
 ext4_try_to_allocate_with_rsv(struct super_block *sb, handle_t *handle,
-                        unsigned int group, struct buffer_head *bitmap_bh,
+                        ext4_group_t group, struct buffer_head *bitmap_bh,
                         ext4_grpblk_t grp_goal,
                         struct ext4_reserve_window_node * my_rsv,
                         unsigned long *count, int *errp)
@@ -1528,12 +1529,12 @@ ext4_fsblk_t ext4_new_blocks(handle_t *handle, struct inode *inode,
 {
         struct buffer_head *bitmap_bh = NULL;
         struct buffer_head *gdp_bh;
-        unsigned long group_no;
-        int goal_group;
+        ext4_group_t group_no;
+        ext4_group_t goal_group;
         ext4_grpblk_t grp_target_blk;   /* blockgroup relative goal block */
         ext4_grpblk_t grp_alloc_blk;    /* blockgroup-relative allocated block*/
         ext4_fsblk_t ret_block;         /* filesyetem-wide allocated block */
-        int bgi;                        /* blockgroup iteration index */
+        ext4_group_t bgi;                       /* blockgroup iteration index */
         int fatal = 0, err;
         int performed_allocation = 0;
         ext4_grpblk_t free_blocks;      /* number of free blocks in a group */
@@ -1544,10 +1545,7 @@ ext4_fsblk_t ext4_new_blocks(handle_t *handle, struct inode *inode,
         struct ext4_reserve_window_node *my_rsv = NULL;
         struct ext4_block_alloc_info *block_i;
         unsigned short windowsz = 0;
-#ifdef EXT4FS_DEBUG
-        static int goal_hits, goal_attempts;
-#endif
-        unsigned long ngroups;
+        ext4_group_t ngroups;
         unsigned long num = *count;
 
         *errp = -ENOSPC;
@@ -1743,9 +1741,6 @@ allocated:
          * list of some description.  We don't know in advance whether
          * the caller wants to use it as metadata or data.
          */
-        ext4_debug("allocating block %lu. Goal hits %d of %d.\n",
-                        ret_block, goal_hits, goal_attempts);
-
         spin_lock(sb_bgl_lock(sbi, group_no));
         if (gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT))
                 gdp->bg_flags &= cpu_to_le16(~EXT4_BG_BLOCK_UNINIT);
@@ -1804,8 +1799,8 @@ ext4_fsblk_t ext4_count_free_blocks(struct super_block *sb)
 {
         ext4_fsblk_t desc_count;
         struct ext4_group_desc *gdp;
-        int i;
-        unsigned long ngroups = EXT4_SB(sb)->s_groups_count;
+        ext4_group_t i;
+        ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
 #ifdef EXT4FS_DEBUG
         struct ext4_super_block *es;
         ext4_fsblk_t bitmap_count;
@@ -1829,7 +1824,7 @@ ext4_fsblk_t ext4_count_free_blocks(struct super_block *sb)
                         continue;
 
                 x = ext4_count_free(bitmap_bh, sb->s_blocksize);
-                printk("group %d: stored = %d, counted = %lu\n",
+                printk(KERN_DEBUG "group %lu: stored = %d, counted = %lu\n",
                         i, le16_to_cpu(gdp->bg_free_blocks_count), x);
                 bitmap_count += x;
         }
@@ -1853,7 +1848,7 @@ ext4_fsblk_t ext4_count_free_blocks(struct super_block *sb)
 #endif
 }
 
-static inline int test_root(int a, int b)
+static inline int test_root(ext4_group_t a, int b)
 {
         int num = b;
 
@@ -1862,7 +1857,7 @@ static inline int test_root(int a, int b)
         return num == a;
 }
 
-static int ext4_group_sparse(int group)
+static int ext4_group_sparse(ext4_group_t group)
 {
         if (group <= 1)
                 return 1;
@@ -1880,7 +1875,7 @@ static int ext4_group_sparse(int group)
  *      Return the number of blocks used by the superblock (primary or backup)
  *      in this group.  Currently this will be only 0 or 1.
  */
-int ext4_bg_has_super(struct super_block *sb, int group)
+int ext4_bg_has_super(struct super_block *sb, ext4_group_t group)
 {
         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
                                 EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER) &&
@@ -1889,18 +1884,20 @@ int ext4_bg_has_super(struct super_block *sb, int group)
         return 1;
 }
 
-static unsigned long ext4_bg_num_gdb_meta(struct super_block *sb, int group)
+static unsigned long ext4_bg_num_gdb_meta(struct super_block *sb,
+                                        ext4_group_t group)
 {
         unsigned long metagroup = group / EXT4_DESC_PER_BLOCK(sb);
-        unsigned long first = metagroup * EXT4_DESC_PER_BLOCK(sb);
-        unsigned long last = first + EXT4_DESC_PER_BLOCK(sb) - 1;
+        ext4_group_t first = metagroup * EXT4_DESC_PER_BLOCK(sb);
+        ext4_group_t last = first + EXT4_DESC_PER_BLOCK(sb) - 1;
 
         if (group == first || group == first + 1 || group == last)
                 return 1;
         return 0;
 }
 
-static unsigned long ext4_bg_num_gdb_nometa(struct super_block *sb, int group)
+static unsigned long ext4_bg_num_gdb_nometa(struct super_block *sb,
+                                        ext4_group_t group)
 {
         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
                                 EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER) &&
@@ -1918,7 +1915,7 @@ static unsigned long ext4_bg_num_gdb_nometa(struct super_block *sb, int group)
  *      (primary or backup) in this group.  In the future there may be a
  *      different number of descriptor blocks in each group.
  */
-unsigned long ext4_bg_num_gdb(struct super_block *sb, int group)
+unsigned long ext4_bg_num_gdb(struct super_block *sb, ext4_group_t group)
 {
         unsigned long first_meta_bg =
                         le32_to_cpu(EXT4_SB(sb)->s_es->s_first_meta_bg);
diff --git a/fs/ext4/group.h b/fs/ext4/group.h
index 1577910bb58b..7eb0604e7eea 100644
--- a/fs/ext4/group.h
+++ b/fs/ext4/group.h
@@ -14,14 +14,16 @@ extern __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 group,
 extern int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 group,
                                        struct ext4_group_desc *gdp);
 struct buffer_head *read_block_bitmap(struct super_block *sb,
-                                      unsigned int block_group);
+                                      ext4_group_t block_group);
 extern unsigned ext4_init_block_bitmap(struct super_block *sb,
-                                       struct buffer_head *bh, int group,
+                                       struct buffer_head *bh,
+                                       ext4_group_t group,
                                        struct ext4_group_desc *desc);
 #define ext4_free_blocks_after_init(sb, group, desc)                    \
                 ext4_init_block_bitmap(sb, NULL, group, desc)
 extern unsigned ext4_init_inode_bitmap(struct super_block *sb,
-                                       struct buffer_head *bh, int group,
+                                       struct buffer_head *bh,
+                                       ext4_group_t group,
                                        struct ext4_group_desc *desc);
 extern void mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
 #endif /* _LINUX_EXT4_GROUP_H */
diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index c61f37fd3f05..64dea8689e1f 100644
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -64,8 +64,8 @@ void mark_bitmap_end(int start_bit, int end_bit, char *bitmap)
 }
 
 /* Initializes an uninitialized inode bitmap */
-unsigned ext4_init_inode_bitmap(struct super_block *sb,
-                                struct buffer_head *bh, int block_group,
+unsigned ext4_init_inode_bitmap(struct super_block *sb, struct buffer_head *bh,
+                                ext4_group_t block_group,
                                 struct ext4_group_desc *gdp)
 {
         struct ext4_sb_info *sbi = EXT4_SB(sb);
@@ -75,7 +75,7 @@ unsigned ext4_init_inode_bitmap(struct super_block *sb,
         /* If checksum is bad mark all blocks and inodes use to prevent
          * allocation, essentially implementing a per-group read-only flag. */
         if (!ext4_group_desc_csum_verify(sbi, block_group, gdp)) {
-                ext4_error(sb, __FUNCTION__, "Checksum bad for group %u\n",
+                ext4_error(sb, __FUNCTION__, "Checksum bad for group %lu\n",
                            block_group);
                 gdp->bg_free_blocks_count = 0;
                 gdp->bg_free_inodes_count = 0;
@@ -98,7 +98,7 @@ unsigned ext4_init_inode_bitmap(struct super_block *sb,
  * Return buffer_head of bitmap on success or NULL.
  */
 static struct buffer_head *
-read_inode_bitmap(struct super_block * sb, unsigned long block_group)
+read_inode_bitmap(struct super_block *sb, ext4_group_t block_group)
 {
         struct ext4_group_desc *desc;
         struct buffer_head *bh = NULL;
@@ -152,7 +152,7 @@ void ext4_free_inode (handle_t *handle, struct inode * inode)
         unsigned long ino;
         struct buffer_head *bitmap_bh = NULL;
         struct buffer_head *bh2;
-        unsigned long block_group;
+        ext4_group_t block_group;
         unsigned long bit;
         struct ext4_group_desc * gdp;
         struct ext4_super_block * es;
@@ -260,12 +260,12 @@ error_return:
  * For other inodes, search forward from the parent directory\'s block
  * group to find a free inode.
  */
-static int find_group_dir(struct super_block *sb, struct inode *parent)
+static ext4_group_t find_group_dir(struct super_block *sb, struct inode *parent)
 {
-        int ngroups = EXT4_SB(sb)->s_groups_count;
+        ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
         unsigned int freei, avefreei;
         struct ext4_group_desc *desc, *best_desc = NULL;
-        int group, best_group = -1;
+        ext4_group_t group, best_group = -1;
 
         freei = percpu_counter_read_positive(&EXT4_SB(sb)->s_freeinodes_counter);
         avefreei = freei / ngroups;
@@ -314,12 +314,13 @@ static int find_group_dir(struct super_block *sb, struct inode *parent)
 #define INODE_COST 64
 #define BLOCK_COST 256
 
-static int find_group_orlov(struct super_block *sb, struct inode *parent)
+static ext4_group_t find_group_orlov(struct super_block *sb,
+                                      struct inode *parent)
 {
-        int parent_group = EXT4_I(parent)->i_block_group;
+        ext4_group_t parent_group = EXT4_I(parent)->i_block_group;
         struct ext4_sb_info *sbi = EXT4_SB(sb);
         struct ext4_super_block *es = sbi->s_es;
-        int ngroups = sbi->s_groups_count;
+        ext4_group_t ngroups = sbi->s_groups_count;
         int inodes_per_group = EXT4_INODES_PER_GROUP(sb);
         unsigned int freei, avefreei;
         ext4_fsblk_t freeb, avefreeb;
@@ -327,7 +328,7 @@ static int find_group_orlov(struct super_block *sb, struct inode *parent)
         unsigned int ndirs;
         int max_debt, max_dirs, min_inodes;
         ext4_grpblk_t min_blocks;
-        int group = -1, i;
+        ext4_group_t group = -1, i;
         struct ext4_group_desc *desc;
 
         freei = percpu_counter_read_positive(&sbi->s_freeinodes_counter);
@@ -340,7 +341,7 @@ static int find_group_orlov(struct super_block *sb, struct inode *parent)
         if ((parent == sb->s_root->d_inode) ||
             (EXT4_I(parent)->i_flags & EXT4_TOPDIR_FL)) {
                 int best_ndir = inodes_per_group;
-                int best_group = -1;
+                ext4_group_t best_group = -1;
 
                 get_random_bytes(&group, sizeof(group));
                 parent_group = (unsigned)group % ngroups;
@@ -415,12 +416,13 @@ fallback:
         return -1;
 }
 
-static int find_group_other(struct super_block *sb, struct inode *parent)
+static ext4_group_t find_group_other(struct super_block *sb,
+                                        struct inode *parent)
 {
-        int parent_group = EXT4_I(parent)->i_block_group;
-        int ngroups = EXT4_SB(sb)->s_groups_count;
+        ext4_group_t parent_group = EXT4_I(parent)->i_block_group;
+        ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
         struct ext4_group_desc *desc;
-        int group, i;
+        ext4_group_t group, i;
 
         /*
          * Try to place the inode in its parent directory
@@ -487,7 +489,7 @@ struct inode *ext4_new_inode(handle_t *handle, struct inode * dir, int mode)
         struct super_block *sb;
         struct buffer_head *bitmap_bh = NULL;
         struct buffer_head *bh2;
-        int group;
+        ext4_group_t group;
         unsigned long ino = 0;
         struct inode * inode;
         struct ext4_group_desc * gdp = NULL;
@@ -583,7 +585,7 @@ got:
             ino > EXT4_INODES_PER_GROUP(sb)) {
                 ext4_error(sb, __FUNCTION__,
                            "reserved inode or inode > inodes count - "
-                           "block_group = %d, inode=%lu", group,
+                           "block_group = %lu, inode=%lu", group,
                            ino + group * EXT4_INODES_PER_GROUP(sb));
                 err = -EIO;
                 goto fail;
@@ -777,7 +779,7 @@ fail_drop:
 struct inode *ext4_orphan_get(struct super_block *sb, unsigned long ino)
 {
         unsigned long max_ino = le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count);
-        unsigned long block_group;
+        ext4_group_t block_group;
         int bit;
         struct buffer_head *bitmap_bh = NULL;
         struct inode *inode = NULL;
@@ -833,7 +835,7 @@ unsigned long ext4_count_free_inodes (struct super_block * sb)
 {
         unsigned long desc_count;
         struct ext4_group_desc *gdp;
-        int i;
+        ext4_group_t i;
 #ifdef EXT4FS_DEBUG
         struct ext4_super_block *es;
         unsigned long bitmap_count, x;
@@ -879,7 +881,7 @@ unsigned long ext4_count_free_inodes (struct super_block * sb)
 unsigned long ext4_count_dirs (struct super_block * sb)
 {
         unsigned long count = 0;
-        int i;
+        ext4_group_t i;
 
         for (i = 0; i < EXT4_SB(sb)->s_groups_count; i++) {
                 struct ext4_group_desc *gdp = ext4_get_group_desc (sb, i, NULL);
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 488f829a8879..1ee19c918686 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -2464,7 +2464,8 @@ out_stop:
 static ext4_fsblk_t ext4_get_inode_block(struct super_block *sb,
                 unsigned long ino, struct ext4_iloc *iloc)
 {
-        unsigned long desc, group_desc, block_group;
+        unsigned long desc, group_desc;
+        ext4_group_t block_group;
         unsigned long offset;
         ext4_fsblk_t block;
         struct buffer_head *bh;
@@ -2551,7 +2552,7 @@ static int __ext4_get_inode_loc(struct inode *inode,
                         struct ext4_group_desc *desc;
                         int inodes_per_buffer;
                         int inode_offset, i;
-                        int block_group;
+                        ext4_group_t block_group;
                         int start;
 
                         block_group = (inode->i_ino - 1) /
diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c
index bd8a52bb3999..7090c2d25c76 100644
--- a/fs/ext4/resize.c
+++ b/fs/ext4/resize.c
@@ -28,7 +28,7 @@ static int verify_group_input(struct super_block *sb,
         struct ext4_super_block *es = sbi->s_es;
         ext4_fsblk_t start = ext4_blocks_count(es);
         ext4_fsblk_t end = start + input->blocks_count;
-        unsigned group = input->group;
+        ext4_group_t group = input->group;
         ext4_fsblk_t itend = input->inode_table + sbi->s_itb_per_group;
         unsigned overhead = ext4_bg_has_super(sb, group) ?
                 (1 + ext4_bg_num_gdb(sb, group) +
@@ -357,7 +357,7 @@ static int verify_reserved_gdb(struct super_block *sb,
                                struct buffer_head *primary)
 {
         const ext4_fsblk_t blk = primary->b_blocknr;
-        const unsigned long end = EXT4_SB(sb)->s_groups_count;
+        const ext4_group_t end = EXT4_SB(sb)->s_groups_count;
         unsigned three = 1;
         unsigned five = 5;
         unsigned seven = 7;
@@ -656,12 +656,12 @@ static void update_backups(struct super_block *sb,
                            int blk_off, char *data, int size)
 {
         struct ext4_sb_info *sbi = EXT4_SB(sb);
-        const unsigned long last = sbi->s_groups_count;
+        const ext4_group_t last = sbi->s_groups_count;
         const int bpg = EXT4_BLOCKS_PER_GROUP(sb);
         unsigned three = 1;
         unsigned five = 5;
         unsigned seven = 7;
-        unsigned group;
+        ext4_group_t group;
         int rest = sb->s_blocksize - size;
         handle_t *handle;
         int err = 0, err2;
@@ -716,7 +716,7 @@ static void update_backups(struct super_block *sb,
 exit_err:
         if (err) {
                 ext4_warning(sb, __FUNCTION__,
-                             "can't update backup for group %d (err %d), "
+                             "can't update backup for group %lu (err %d), "
                              "forcing fsck on next reboot", group, err);
                 sbi->s_mount_state &= ~EXT4_VALID_FS;
                 sbi->s_es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
@@ -952,7 +952,7 @@ int ext4_group_extend(struct super_block *sb, struct ext4_super_block *es,
                       ext4_fsblk_t n_blocks_count)
 {
         ext4_fsblk_t o_blocks_count;
-        unsigned long o_groups_count;
+        ext4_group_t o_groups_count;
         ext4_grpblk_t last;
         ext4_grpblk_t add;
         struct buffer_head * bh;
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 6302b036c121..df8842b43544 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1364,7 +1364,7 @@ static int ext4_check_descriptors (struct super_block * sb)
         struct ext4_group_desc * gdp = NULL;
         int desc_block = 0;
         int flexbg_flag = 0;
-        int i;
+        ext4_group_t i;
 
         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
                 flexbg_flag = 1;
@@ -1386,7 +1386,7 @@ static int ext4_check_descriptors (struct super_block * sb)
                 if (block_bitmap < first_block || block_bitmap > last_block)
                 {
                         ext4_error (sb, "ext4_check_descriptors",
-                                    "Block bitmap for group %d"
+                                    "Block bitmap for group %lu"
                                     " not in group (block %llu)!",
                                     i, block_bitmap);
                         return 0;
@@ -1395,7 +1395,7 @@ static int ext4_check_descriptors (struct super_block * sb)
                 if (inode_bitmap < first_block || inode_bitmap > last_block)
                 {
                         ext4_error (sb, "ext4_check_descriptors",
-                                    "Inode bitmap for group %d"
+                                    "Inode bitmap for group %lu"
                                     " not in group (block %llu)!",
                                     i, inode_bitmap);
                         return 0;
@@ -1405,17 +1405,16 @@ static int ext4_check_descriptors (struct super_block * sb)
                     inode_table + sbi->s_itb_per_group - 1 > last_block)
                 {
                         ext4_error (sb, "ext4_check_descriptors",
-                                    "Inode table for group %d"
+                                    "Inode table for group %lu"
                                     " not in group (block %llu)!",
                                     i, inode_table);
                         return 0;
                 }
                 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
                         ext4_error(sb, __FUNCTION__,
-                                   "Checksum for group %d failed (%u!=%u)\n", i,
-                                   le16_to_cpu(ext4_group_desc_csum(sbi, i,
-                                                                    gdp)),
-                                   le16_to_cpu(gdp->bg_checksum));
+                                   "Checksum for group %lu failed (%u!=%u)\n",
+                                    i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
+                                    gdp)), le16_to_cpu(gdp->bg_checksum));
                         return 0;
                 }
                 if (!flexbg_flag)
@@ -1429,7 +1428,6 @@ static int ext4_check_descriptors (struct super_block * sb)
         return 1;
 }
 
-
 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
  * the superblock) which were deleted from all directories, but held open by
  * a process at the time of a crash.  We walk the list and try to delete these
@@ -1570,7 +1568,7 @@ static ext4_fsblk_t descriptor_loc(struct super_block *sb,
                                 ext4_fsblk_t logical_sb_block, int nr)
 {
         struct ext4_sb_info *sbi = EXT4_SB(sb);
-        unsigned long bg, first_meta_bg;
+        ext4_group_t bg, first_meta_bg;
         int has_super = 0;
 
         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
@@ -2678,7 +2676,7 @@ static int ext4_statfs (struct dentry * dentry, struct kstatfs * buf)
         if (test_opt(sb, MINIX_DF)) {
                 sbi->s_overhead_last = 0;
         } else if (sbi->s_blocks_last != ext4_blocks_count(es)) {
-                unsigned long ngroups = sbi->s_groups_count, i;
+                ext4_group_t ngroups = sbi->s_groups_count, i;
                 ext4_fsblk_t overhead = 0;
                 smp_rmb();
 
diff --git a/include/linux/ext4_fs.h b/include/linux/ext4_fs.h
index 5e2da0974d16..e1103c2a0d42 100644
--- a/include/linux/ext4_fs.h
+++ b/include/linux/ext4_fs.h
@@ -830,7 +830,7 @@ struct ext4_iloc
 {
         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 @@ struct dir_private_info {
 
 /* 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 @@ extern unsigned int ext4_block_group(struct super_block *sb,
                         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 void ext4_free_blocks_sb (handle_t *handle, struct super_block *sb,
 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 6c610b67b047..2b4e3700c725 100644
--- a/include/linux/ext4_fs_i.h
+++ b/include/linux/ext4_fs_i.h
@@ -30,6 +30,9 @@ typedef unsigned long long ext4_fsblk_t;
 /* 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 @@ struct ext4_inode_info {
          * 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 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 */