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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/ext2/balloc.c
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Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'fs/ext2/balloc.c')
-rw-r--r--fs/ext2/balloc.c699
1 files changed, 699 insertions, 0 deletions
diff --git a/fs/ext2/balloc.c b/fs/ext2/balloc.c
new file mode 100644
index 0000000..6591abe
--- /dev/null
+++ b/fs/ext2/balloc.c
@@ -0,0 +1,699 @@
+/*
+ * linux/fs/ext2/balloc.c
+ *
+ * Copyright (C) 1992, 1993, 1994, 1995
+ * Remy Card (card@masi.ibp.fr)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ *
+ * Enhanced block allocation by Stephen Tweedie (sct@redhat.com), 1993
+ * Big-endian to little-endian byte-swapping/bitmaps by
+ * David S. Miller (davem@caip.rutgers.edu), 1995
+ */
+
+#include <linux/config.h>
+#include "ext2.h"
+#include <linux/quotaops.h>
+#include <linux/sched.h>
+#include <linux/buffer_head.h>
+
+/*
+ * balloc.c contains the blocks allocation and deallocation routines
+ */
+
+/*
+ * The free blocks are managed by bitmaps. A file system contains several
+ * blocks groups. Each group contains 1 bitmap block for blocks, 1 bitmap
+ * block for inodes, N blocks for the inode table and data blocks.
+ *
+ * The file system contains group descriptors which are located after the
+ * super block. Each descriptor contains the number of the bitmap block and
+ * the free blocks count in the block. The descriptors are loaded in memory
+ * when a file system is mounted (see ext2_read_super).
+ */
+
+
+#define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
+
+struct ext2_group_desc * ext2_get_group_desc(struct super_block * sb,
+ unsigned int block_group,
+ struct buffer_head ** bh)
+{
+ unsigned long group_desc;
+ unsigned long offset;
+ struct ext2_group_desc * desc;
+ struct ext2_sb_info *sbi = EXT2_SB(sb);
+
+ if (block_group >= sbi->s_groups_count) {
+ ext2_error (sb, "ext2_get_group_desc",
+ "block_group >= groups_count - "
+ "block_group = %d, groups_count = %lu",
+ block_group, sbi->s_groups_count);
+
+ return NULL;
+ }
+
+ group_desc = block_group >> EXT2_DESC_PER_BLOCK_BITS(sb);
+ offset = block_group & (EXT2_DESC_PER_BLOCK(sb) - 1);
+ if (!sbi->s_group_desc[group_desc]) {
+ ext2_error (sb, "ext2_get_group_desc",
+ "Group descriptor not loaded - "
+ "block_group = %d, group_desc = %lu, desc = %lu",
+ block_group, group_desc, offset);
+ return NULL;
+ }
+
+ desc = (struct ext2_group_desc *) sbi->s_group_desc[group_desc]->b_data;
+ if (bh)
+ *bh = sbi->s_group_desc[group_desc];
+ return desc + offset;
+}
+
+/*
+ * Read the bitmap for a given block_group, reading into the specified
+ * slot in the superblock's bitmap cache.
+ *
+ * Return buffer_head on success or NULL in case of failure.
+ */
+static struct buffer_head *
+read_block_bitmap(struct super_block *sb, unsigned int block_group)
+{
+ struct ext2_group_desc * desc;
+ struct buffer_head * bh = NULL;
+
+ desc = ext2_get_group_desc (sb, block_group, NULL);
+ if (!desc)
+ goto error_out;
+ bh = sb_bread(sb, le32_to_cpu(desc->bg_block_bitmap));
+ if (!bh)
+ ext2_error (sb, "read_block_bitmap",
+ "Cannot read block bitmap - "
+ "block_group = %d, block_bitmap = %u",
+ block_group, le32_to_cpu(desc->bg_block_bitmap));
+error_out:
+ return bh;
+}
+
+/*
+ * Set sb->s_dirt here because the superblock was "logically" altered. We
+ * need to recalculate its free blocks count and flush it out.
+ */
+static int reserve_blocks(struct super_block *sb, int count)
+{
+ struct ext2_sb_info *sbi = EXT2_SB(sb);
+ struct ext2_super_block *es = sbi->s_es;
+ unsigned free_blocks;
+ unsigned root_blocks;
+
+ free_blocks = percpu_counter_read_positive(&sbi->s_freeblocks_counter);
+ root_blocks = le32_to_cpu(es->s_r_blocks_count);
+
+ if (free_blocks < count)
+ count = free_blocks;
+
+ if (free_blocks < root_blocks + count && !capable(CAP_SYS_RESOURCE) &&
+ sbi->s_resuid != current->fsuid &&
+ (sbi->s_resgid == 0 || !in_group_p (sbi->s_resgid))) {
+ /*
+ * We are too close to reserve and we are not privileged.
+ * Can we allocate anything at all?
+ */
+ if (free_blocks > root_blocks)
+ count = free_blocks - root_blocks;
+ else
+ return 0;
+ }
+
+ percpu_counter_mod(&sbi->s_freeblocks_counter, -count);
+ sb->s_dirt = 1;
+ return count;
+}
+
+static void release_blocks(struct super_block *sb, int count)
+{
+ if (count) {
+ struct ext2_sb_info *sbi = EXT2_SB(sb);
+
+ percpu_counter_mod(&sbi->s_freeblocks_counter, count);
+ sb->s_dirt = 1;
+ }
+}
+
+static int group_reserve_blocks(struct ext2_sb_info *sbi, int group_no,
+ struct ext2_group_desc *desc, struct buffer_head *bh, int count)
+{
+ unsigned free_blocks;
+
+ if (!desc->bg_free_blocks_count)
+ return 0;
+
+ spin_lock(sb_bgl_lock(sbi, group_no));
+ free_blocks = le16_to_cpu(desc->bg_free_blocks_count);
+ if (free_blocks < count)
+ count = free_blocks;
+ desc->bg_free_blocks_count = cpu_to_le16(free_blocks - count);
+ spin_unlock(sb_bgl_lock(sbi, group_no));
+ mark_buffer_dirty(bh);
+ return count;
+}
+
+static void group_release_blocks(struct super_block *sb, int group_no,
+ struct ext2_group_desc *desc, struct buffer_head *bh, int count)
+{
+ if (count) {
+ struct ext2_sb_info *sbi = EXT2_SB(sb);
+ unsigned free_blocks;
+
+ spin_lock(sb_bgl_lock(sbi, group_no));
+ free_blocks = le16_to_cpu(desc->bg_free_blocks_count);
+ desc->bg_free_blocks_count = cpu_to_le16(free_blocks + count);
+ spin_unlock(sb_bgl_lock(sbi, group_no));
+ sb->s_dirt = 1;
+ mark_buffer_dirty(bh);
+ }
+}
+
+/* Free given blocks, update quota and i_blocks field */
+void ext2_free_blocks (struct inode * inode, unsigned long block,
+ unsigned long count)
+{
+ struct buffer_head *bitmap_bh = NULL;
+ struct buffer_head * bh2;
+ unsigned long block_group;
+ unsigned long bit;
+ unsigned long i;
+ unsigned long overflow;
+ struct super_block * sb = inode->i_sb;
+ struct ext2_sb_info * sbi = EXT2_SB(sb);
+ struct ext2_group_desc * desc;
+ struct ext2_super_block * es = sbi->s_es;
+ unsigned freed = 0, group_freed;
+
+ if (block < le32_to_cpu(es->s_first_data_block) ||
+ block + count < block ||
+ block + count > le32_to_cpu(es->s_blocks_count)) {
+ ext2_error (sb, "ext2_free_blocks",
+ "Freeing blocks not in datazone - "
+ "block = %lu, count = %lu", block, count);
+ goto error_return;
+ }
+
+ ext2_debug ("freeing block(s) %lu-%lu\n", block, block + count - 1);
+
+do_more:
+ overflow = 0;
+ block_group = (block - le32_to_cpu(es->s_first_data_block)) /
+ EXT2_BLOCKS_PER_GROUP(sb);
+ bit = (block - le32_to_cpu(es->s_first_data_block)) %
+ EXT2_BLOCKS_PER_GROUP(sb);
+ /*
+ * Check to see if we are freeing blocks across a group
+ * boundary.
+ */
+ if (bit + count > EXT2_BLOCKS_PER_GROUP(sb)) {
+ overflow = bit + count - EXT2_BLOCKS_PER_GROUP(sb);
+ count -= overflow;
+ }
+ brelse(bitmap_bh);
+ bitmap_bh = read_block_bitmap(sb, block_group);
+ if (!bitmap_bh)
+ goto error_return;
+
+ desc = ext2_get_group_desc (sb, block_group, &bh2);
+ if (!desc)
+ goto error_return;
+
+ if (in_range (le32_to_cpu(desc->bg_block_bitmap), block, count) ||
+ in_range (le32_to_cpu(desc->bg_inode_bitmap), block, count) ||
+ in_range (block, le32_to_cpu(desc->bg_inode_table),
+ sbi->s_itb_per_group) ||
+ in_range (block + count - 1, le32_to_cpu(desc->bg_inode_table),
+ sbi->s_itb_per_group))
+ ext2_error (sb, "ext2_free_blocks",
+ "Freeing blocks in system zones - "
+ "Block = %lu, count = %lu",
+ block, count);
+
+ for (i = 0, group_freed = 0; i < count; i++) {
+ if (!ext2_clear_bit_atomic(sb_bgl_lock(sbi, block_group),
+ bit + i, bitmap_bh->b_data)) {
+ ext2_error(sb, __FUNCTION__,
+ "bit already cleared for block %lu", block + i);
+ } else {
+ group_freed++;
+ }
+ }
+
+ mark_buffer_dirty(bitmap_bh);
+ if (sb->s_flags & MS_SYNCHRONOUS)
+ sync_dirty_buffer(bitmap_bh);
+
+ group_release_blocks(sb, block_group, desc, bh2, group_freed);
+ freed += group_freed;
+
+ if (overflow) {
+ block += count;
+ count = overflow;
+ goto do_more;
+ }
+error_return:
+ brelse(bitmap_bh);
+ release_blocks(sb, freed);
+ DQUOT_FREE_BLOCK(inode, freed);
+}
+
+static int grab_block(spinlock_t *lock, char *map, unsigned size, int goal)
+{
+ int k;
+ char *p, *r;
+
+ if (!ext2_test_bit(goal, map))
+ goto got_it;
+
+repeat:
+ if (goal) {
+ /*
+ * The goal was occupied; search forward for a free
+ * block within the next XX blocks.
+ *
+ * end_goal is more or less random, but it has to be
+ * less than EXT2_BLOCKS_PER_GROUP. Aligning up to the
+ * next 64-bit boundary is simple..
+ */
+ k = (goal + 63) & ~63;
+ goal = ext2_find_next_zero_bit(map, k, goal);
+ if (goal < k)
+ goto got_it;
+ /*
+ * Search in the remainder of the current group.
+ */
+ }
+
+ p = map + (goal >> 3);
+ r = memscan(p, 0, (size - goal + 7) >> 3);
+ k = (r - map) << 3;
+ if (k < size) {
+ /*
+ * We have succeeded in finding a free byte in the block
+ * bitmap. Now search backwards to find the start of this
+ * group of free blocks - won't take more than 7 iterations.
+ */
+ for (goal = k; goal && !ext2_test_bit (goal - 1, map); goal--)
+ ;
+ goto got_it;
+ }
+
+ k = ext2_find_next_zero_bit ((u32 *)map, size, goal);
+ if (k < size) {
+ goal = k;
+ goto got_it;
+ }
+ return -1;
+got_it:
+ if (ext2_set_bit_atomic(lock, goal, (void *) map))
+ goto repeat;
+ return goal;
+}
+
+/*
+ * ext2_new_block uses a goal block to assist allocation. If the goal is
+ * free, or there is a free block within 32 blocks of the goal, that block
+ * is allocated. Otherwise a forward search is made for a free block; within
+ * each block group the search first looks for an entire free byte in the block
+ * bitmap, and then for any free bit if that fails.
+ * This function also updates quota and i_blocks field.
+ */
+int ext2_new_block(struct inode *inode, unsigned long goal,
+ u32 *prealloc_count, u32 *prealloc_block, int *err)
+{
+ struct buffer_head *bitmap_bh = NULL;
+ struct buffer_head *gdp_bh; /* bh2 */
+ struct ext2_group_desc *desc;
+ int group_no; /* i */
+ int ret_block; /* j */
+ int group_idx; /* k */
+ int target_block; /* tmp */
+ int block = 0;
+ struct super_block *sb = inode->i_sb;
+ struct ext2_sb_info *sbi = EXT2_SB(sb);
+ struct ext2_super_block *es = sbi->s_es;
+ unsigned group_size = EXT2_BLOCKS_PER_GROUP(sb);
+ unsigned prealloc_goal = es->s_prealloc_blocks;
+ unsigned group_alloc = 0, es_alloc, dq_alloc;
+ int nr_scanned_groups;
+
+ if (!prealloc_goal--)
+ prealloc_goal = EXT2_DEFAULT_PREALLOC_BLOCKS - 1;
+ if (!prealloc_count || *prealloc_count)
+ prealloc_goal = 0;
+
+ if (DQUOT_ALLOC_BLOCK(inode, 1)) {
+ *err = -EDQUOT;
+ goto out;
+ }
+
+ while (prealloc_goal && DQUOT_PREALLOC_BLOCK(inode, prealloc_goal))
+ prealloc_goal--;
+
+ dq_alloc = prealloc_goal + 1;
+ es_alloc = reserve_blocks(sb, dq_alloc);
+ if (!es_alloc) {
+ *err = -ENOSPC;
+ goto out_dquot;
+ }
+
+ ext2_debug ("goal=%lu.\n", goal);
+
+ if (goal < le32_to_cpu(es->s_first_data_block) ||
+ goal >= le32_to_cpu(es->s_blocks_count))
+ goal = le32_to_cpu(es->s_first_data_block);
+ group_no = (goal - le32_to_cpu(es->s_first_data_block)) / group_size;
+ desc = ext2_get_group_desc (sb, group_no, &gdp_bh);
+ if (!desc) {
+ /*
+ * gdp_bh may still be uninitialised. But group_release_blocks
+ * will not touch it because group_alloc is zero.
+ */
+ goto io_error;
+ }
+
+ group_alloc = group_reserve_blocks(sbi, group_no, desc,
+ gdp_bh, es_alloc);
+ if (group_alloc) {
+ ret_block = ((goal - le32_to_cpu(es->s_first_data_block)) %
+ group_size);
+ brelse(bitmap_bh);
+ bitmap_bh = read_block_bitmap(sb, group_no);
+ if (!bitmap_bh)
+ goto io_error;
+
+ ext2_debug("goal is at %d:%d.\n", group_no, ret_block);
+
+ ret_block = grab_block(sb_bgl_lock(sbi, group_no),
+ bitmap_bh->b_data, group_size, ret_block);
+ if (ret_block >= 0)
+ goto got_block;
+ group_release_blocks(sb, group_no, desc, gdp_bh, group_alloc);
+ group_alloc = 0;
+ }
+
+ ext2_debug ("Bit not found in block group %d.\n", group_no);
+
+ /*
+ * Now search the rest of the groups. We assume that
+ * i and desc correctly point to the last group visited.
+ */
+ nr_scanned_groups = 0;
+retry:
+ for (group_idx = 0; !group_alloc &&
+ group_idx < sbi->s_groups_count; group_idx++) {
+ group_no++;
+ if (group_no >= sbi->s_groups_count)
+ group_no = 0;
+ desc = ext2_get_group_desc(sb, group_no, &gdp_bh);
+ if (!desc)
+ goto io_error;
+ group_alloc = group_reserve_blocks(sbi, group_no, desc,
+ gdp_bh, es_alloc);
+ }
+ if (!group_alloc) {
+ *err = -ENOSPC;
+ goto out_release;
+ }
+ brelse(bitmap_bh);
+ bitmap_bh = read_block_bitmap(sb, group_no);
+ if (!bitmap_bh)
+ goto io_error;
+
+ ret_block = grab_block(sb_bgl_lock(sbi, group_no), bitmap_bh->b_data,
+ group_size, 0);
+ if (ret_block < 0) {
+ /*
+ * If a free block counter is corrupted we can loop inifintely.
+ * Detect that here.
+ */
+ nr_scanned_groups++;
+ if (nr_scanned_groups > 2 * sbi->s_groups_count) {
+ ext2_error(sb, "ext2_new_block",
+ "corrupted free blocks counters");
+ goto io_error;
+ }
+ /*
+ * Someone else grabbed the last free block in this blockgroup
+ * before us. Retry the scan.
+ */
+ group_release_blocks(sb, group_no, desc, gdp_bh, group_alloc);
+ group_alloc = 0;
+ goto retry;
+ }
+
+got_block:
+ ext2_debug("using block group %d(%d)\n",
+ group_no, desc->bg_free_blocks_count);
+
+ target_block = ret_block + group_no * group_size +
+ le32_to_cpu(es->s_first_data_block);
+
+ if (target_block == le32_to_cpu(desc->bg_block_bitmap) ||
+ target_block == le32_to_cpu(desc->bg_inode_bitmap) ||
+ in_range(target_block, le32_to_cpu(desc->bg_inode_table),
+ sbi->s_itb_per_group))
+ ext2_error (sb, "ext2_new_block",
+ "Allocating block in system zone - "
+ "block = %u", target_block);
+
+ if (target_block >= le32_to_cpu(es->s_blocks_count)) {
+ ext2_error (sb, "ext2_new_block",
+ "block(%d) >= blocks count(%d) - "
+ "block_group = %d, es == %p ", ret_block,
+ le32_to_cpu(es->s_blocks_count), group_no, es);
+ goto io_error;
+ }
+ block = target_block;
+
+ /* OK, we _had_ allocated something */
+ ext2_debug("found bit %d\n", ret_block);
+
+ dq_alloc--;
+ es_alloc--;
+ group_alloc--;
+
+ /*
+ * Do block preallocation now if required.
+ */
+ write_lock(&EXT2_I(inode)->i_meta_lock);
+ if (group_alloc && !*prealloc_count) {
+ unsigned n;
+
+ for (n = 0; n < group_alloc && ++ret_block < group_size; n++) {
+ if (ext2_set_bit_atomic(sb_bgl_lock(sbi, group_no),
+ ret_block,
+ (void*) bitmap_bh->b_data))
+ break;
+ }
+ *prealloc_block = block + 1;
+ *prealloc_count = n;
+ es_alloc -= n;
+ dq_alloc -= n;
+ group_alloc -= n;
+ }
+ write_unlock(&EXT2_I(inode)->i_meta_lock);
+
+ mark_buffer_dirty(bitmap_bh);
+ if (sb->s_flags & MS_SYNCHRONOUS)
+ sync_dirty_buffer(bitmap_bh);
+
+ ext2_debug ("allocating block %d. ", block);
+
+ *err = 0;
+out_release:
+ group_release_blocks(sb, group_no, desc, gdp_bh, group_alloc);
+ release_blocks(sb, es_alloc);
+out_dquot:
+ DQUOT_FREE_BLOCK(inode, dq_alloc);
+out:
+ brelse(bitmap_bh);
+ return block;
+
+io_error:
+ *err = -EIO;
+ goto out_release;
+}
+
+unsigned long ext2_count_free_blocks (struct super_block * sb)
+{
+ struct ext2_group_desc * desc;
+ unsigned long desc_count = 0;
+ int i;
+#ifdef EXT2FS_DEBUG
+ unsigned long bitmap_count, x;
+ struct ext2_super_block *es;
+
+ lock_super (sb);
+ es = EXT2_SB(sb)->s_es;
+ desc_count = 0;
+ bitmap_count = 0;
+ desc = NULL;
+ for (i = 0; i < EXT2_SB(sb)->s_groups_count; i++) {
+ struct buffer_head *bitmap_bh;
+ desc = ext2_get_group_desc (sb, i, NULL);
+ if (!desc)
+ continue;
+ desc_count += le16_to_cpu(desc->bg_free_blocks_count);
+ bitmap_bh = read_block_bitmap(sb, i);
+ if (!bitmap_bh)
+ continue;
+
+ x = ext2_count_free(bitmap_bh, sb->s_blocksize);
+ printk ("group %d: stored = %d, counted = %lu\n",
+ i, le16_to_cpu(desc->bg_free_blocks_count), x);
+ bitmap_count += x;
+ brelse(bitmap_bh);
+ }
+ printk("ext2_count_free_blocks: stored = %lu, computed = %lu, %lu\n",
+ (long)le32_to_cpu(es->s_free_blocks_count),
+ desc_count, bitmap_count);
+ unlock_super (sb);
+ return bitmap_count;
+#else
+ for (i = 0; i < EXT2_SB(sb)->s_groups_count; i++) {
+ desc = ext2_get_group_desc (sb, i, NULL);
+ if (!desc)
+ continue;
+ desc_count += le16_to_cpu(desc->bg_free_blocks_count);
+ }
+ return desc_count;
+#endif
+}
+
+static inline int
+block_in_use(unsigned long block, struct super_block *sb, unsigned char *map)
+{
+ return ext2_test_bit ((block -
+ le32_to_cpu(EXT2_SB(sb)->s_es->s_first_data_block)) %
+ EXT2_BLOCKS_PER_GROUP(sb), map);
+}
+
+static inline int test_root(int a, int b)
+{
+ int num = b;
+
+ while (a > num)
+ num *= b;
+ return num == a;
+}
+
+static int ext2_group_sparse(int group)
+{
+ if (group <= 1)
+ return 1;
+ return (test_root(group, 3) || test_root(group, 5) ||
+ test_root(group, 7));
+}
+
+/**
+ * ext2_bg_has_super - number of blocks used by the superblock in group
+ * @sb: superblock for filesystem
+ * @group: group number to check
+ *
+ * Return the number of blocks used by the superblock (primary or backup)
+ * in this group. Currently this will be only 0 or 1.
+ */
+int ext2_bg_has_super(struct super_block *sb, int group)
+{
+ if (EXT2_HAS_RO_COMPAT_FEATURE(sb,EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER)&&
+ !ext2_group_sparse(group))
+ return 0;
+ return 1;
+}
+
+/**
+ * ext2_bg_num_gdb - number of blocks used by the group table in group
+ * @sb: superblock for filesystem
+ * @group: group number to check
+ *
+ * Return the number of blocks used by the group descriptor table
+ * (primary or backup) in this group. In the future there may be a
+ * different number of descriptor blocks in each group.
+ */
+unsigned long ext2_bg_num_gdb(struct super_block *sb, int group)
+{
+ if (EXT2_HAS_RO_COMPAT_FEATURE(sb,EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER)&&
+ !ext2_group_sparse(group))
+ return 0;
+ return EXT2_SB(sb)->s_gdb_count;
+}
+
+#ifdef CONFIG_EXT2_CHECK
+/* Called at mount-time, super-block is locked */
+void ext2_check_blocks_bitmap (struct super_block * sb)
+{
+ struct buffer_head *bitmap_bh = NULL;
+ struct ext2_super_block * es;
+ unsigned long desc_count, bitmap_count, x, j;
+ unsigned long desc_blocks;
+ struct ext2_group_desc * desc;
+ int i;
+
+ es = EXT2_SB(sb)->s_es;
+ desc_count = 0;
+ bitmap_count = 0;
+ desc = NULL;
+ for (i = 0; i < EXT2_SB(sb)->s_groups_count; i++) {
+ desc = ext2_get_group_desc (sb, i, NULL);
+ if (!desc)
+ continue;
+ desc_count += le16_to_cpu(desc->bg_free_blocks_count);
+ brelse(bitmap_bh);
+ bitmap_bh = read_block_bitmap(sb, i);
+ if (!bitmap_bh)
+ continue;
+
+ if (ext2_bg_has_super(sb, i) &&
+ !ext2_test_bit(0, bitmap_bh->b_data))
+ ext2_error(sb, __FUNCTION__,
+ "Superblock in group %d is marked free", i);
+
+ desc_blocks = ext2_bg_num_gdb(sb, i);
+ for (j = 0; j < desc_blocks; j++)
+ if (!ext2_test_bit(j + 1, bitmap_bh->b_data))
+ ext2_error(sb, __FUNCTION__,
+ "Descriptor block #%ld in group "
+ "%d is marked free", j, i);
+
+ if (!block_in_use(le32_to_cpu(desc->bg_block_bitmap),
+ sb, bitmap_bh->b_data))
+ ext2_error(sb, "ext2_check_blocks_bitmap",
+ "Block bitmap for group %d is marked free",
+ i);
+
+ if (!block_in_use(le32_to_cpu(desc->bg_inode_bitmap),
+ sb, bitmap_bh->b_data))
+ ext2_error(sb, "ext2_check_blocks_bitmap",
+ "Inode bitmap for group %d is marked free",
+ i);
+
+ for (j = 0; j < EXT2_SB(sb)->s_itb_per_group; j++)
+ if (!block_in_use(le32_to_cpu(desc->bg_inode_table) + j,
+ sb, bitmap_bh->b_data))
+ ext2_error (sb, "ext2_check_blocks_bitmap",
+ "Block #%ld of the inode table in "
+ "group %d is marked free", j, i);
+
+ x = ext2_count_free(bitmap_bh, sb->s_blocksize);
+ if (le16_to_cpu(desc->bg_free_blocks_count) != x)
+ ext2_error (sb, "ext2_check_blocks_bitmap",
+ "Wrong free blocks count for group %d, "
+ "stored = %d, counted = %lu", i,
+ le16_to_cpu(desc->bg_free_blocks_count), x);
+ bitmap_count += x;
+ }
+ if (le32_to_cpu(es->s_free_blocks_count) != bitmap_count)
+ ext2_error (sb, "ext2_check_blocks_bitmap",
+ "Wrong free blocks count in super block, "
+ "stored = %lu, counted = %lu",
+ (unsigned long)le32_to_cpu(es->s_free_blocks_count),
+ bitmap_count);
+ brelse(bitmap_bh);
+}
+#endif