ext4: fix block bitmap validation when bigalloc, ^flex_bg
[pandora-kernel.git] / fs / ext4 / balloc.c
index 4f30380..f91de78 100644 (file)
@@ -88,8 +88,8 @@ unsigned ext4_num_overhead_clusters(struct super_block *sb,
         * unusual file system layouts.
         */
        if (ext4_block_in_group(sb, ext4_block_bitmap(sb, gdp), block_group)) {
-               block_cluster = EXT4_B2C(sbi, (start -
-                                              ext4_block_bitmap(sb, gdp)));
+               block_cluster = EXT4_B2C(sbi,
+                                        ext4_block_bitmap(sb, gdp) - start);
                if (block_cluster < num_clusters)
                        block_cluster = -1;
                else if (block_cluster == num_clusters) {
@@ -100,7 +100,7 @@ unsigned ext4_num_overhead_clusters(struct super_block *sb,
 
        if (ext4_block_in_group(sb, ext4_inode_bitmap(sb, gdp), block_group)) {
                inode_cluster = EXT4_B2C(sbi,
-                                        start - ext4_inode_bitmap(sb, gdp));
+                                        ext4_inode_bitmap(sb, gdp) - start);
                if (inode_cluster < num_clusters)
                        inode_cluster = -1;
                else if (inode_cluster == num_clusters) {
@@ -112,7 +112,7 @@ unsigned ext4_num_overhead_clusters(struct super_block *sb,
        itbl_blk = ext4_inode_table(sb, gdp);
        for (i = 0; i < sbi->s_itb_per_group; i++) {
                if (ext4_block_in_group(sb, itbl_blk + i, block_group)) {
-                       c = EXT4_B2C(sbi, start - itbl_blk + i);
+                       c = EXT4_B2C(sbi, itbl_blk + i - start);
                        if ((c < num_clusters) || (c == inode_cluster) ||
                            (c == block_cluster) || (c == itbl_cluster))
                                continue;
@@ -213,9 +213,9 @@ void ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh,
 /* Return the number of free blocks in a block group.  It is used when
  * the block bitmap is uninitialized, so we can't just count the bits
  * in the bitmap. */
-unsigned ext4_free_blocks_after_init(struct super_block *sb,
-                                    ext4_group_t block_group,
-                                    struct ext4_group_desc *gdp)
+unsigned ext4_free_clusters_after_init(struct super_block *sb,
+                                      ext4_group_t block_group,
+                                      struct ext4_group_desc *gdp)
 {
        return num_clusters_in_group(sb, block_group) - 
                ext4_num_overhead_clusters(sb, block_group, gdp);
@@ -278,6 +278,7 @@ static int ext4_valid_block_bitmap(struct super_block *sb,
                                        unsigned int block_group,
                                        struct buffer_head *bh)
 {
+       struct ext4_sb_info *sbi = EXT4_SB(sb);
        ext4_grpblk_t offset;
        ext4_grpblk_t next_zero_bit;
        ext4_fsblk_t bitmap_blk;
@@ -297,14 +298,14 @@ static int ext4_valid_block_bitmap(struct super_block *sb,
        /* check whether block bitmap block number is set */
        bitmap_blk = ext4_block_bitmap(sb, desc);
        offset = bitmap_blk - group_first_block;
-       if (!ext4_test_bit(offset, bh->b_data))
+       if (!ext4_test_bit(EXT4_B2C(sbi, offset), bh->b_data))
                /* bad block bitmap */
                goto err_out;
 
        /* check whether the inode bitmap block number is set */
        bitmap_blk = ext4_inode_bitmap(sb, desc);
        offset = bitmap_blk - group_first_block;
-       if (!ext4_test_bit(offset, bh->b_data))
+       if (!ext4_test_bit(EXT4_B2C(sbi, offset), bh->b_data))
                /* bad block bitmap */
                goto err_out;
 
@@ -312,9 +313,10 @@ static int ext4_valid_block_bitmap(struct super_block *sb,
        bitmap_blk = ext4_inode_table(sb, desc);
        offset = bitmap_blk - group_first_block;
        next_zero_bit = ext4_find_next_zero_bit(bh->b_data,
-                               offset + EXT4_SB(sb)->s_itb_per_group,
-                               offset);
-       if (next_zero_bit >= offset + EXT4_SB(sb)->s_itb_per_group)
+                       EXT4_B2C(sbi, offset + EXT4_SB(sb)->s_itb_per_group),
+                       EXT4_B2C(sbi, offset));
+       if (next_zero_bit >=
+           EXT4_B2C(sbi, offset + EXT4_SB(sb)->s_itb_per_group))
                /* good bitmap for inode tables */
                return 1;
 
@@ -403,53 +405,59 @@ ext4_read_block_bitmap(struct super_block *sb, ext4_group_t block_group)
 }
 
 /**
- * ext4_has_free_blocks()
+ * ext4_has_free_clusters()
  * @sbi:       in-core super block structure.
- * @nblocks:   number of needed blocks
+ * @nclusters: number of needed blocks
+ * @flags:     flags from ext4_mb_new_blocks()
  *
- * Check if filesystem has nblocks free & available for allocation.
+ * Check if filesystem has nclusters free & available for allocation.
  * On success return 1, return 0 on failure.
  */
-static int ext4_has_free_blocks(struct ext4_sb_info *sbi,
-                               s64 nblocks, unsigned int flags)
+static int ext4_has_free_clusters(struct ext4_sb_info *sbi,
+                                 s64 nclusters, unsigned int flags)
 {
-       s64 free_blocks, dirty_blocks, root_blocks;
+       s64 free_clusters, dirty_clusters, root_clusters;
        struct percpu_counter *fcc = &sbi->s_freeclusters_counter;
-       struct percpu_counter *dbc = &sbi->s_dirtyclusters_counter;
+       struct percpu_counter *dcc = &sbi->s_dirtyclusters_counter;
+
+       free_clusters  = percpu_counter_read_positive(fcc);
+       dirty_clusters = percpu_counter_read_positive(dcc);
 
-       free_blocks  = percpu_counter_read_positive(fcc);
-       dirty_blocks = percpu_counter_read_positive(dbc);
-       root_blocks = ext4_r_blocks_count(sbi->s_es);
+       /*
+        * r_blocks_count should always be multiple of the cluster ratio so
+        * we are safe to do a plane bit shift only.
+        */
+       root_clusters = ext4_r_blocks_count(sbi->s_es) >> sbi->s_cluster_bits;
 
-       if (free_blocks - (nblocks + root_blocks + dirty_blocks) <
-                                               EXT4_FREEBLOCKS_WATERMARK) {
-               free_blocks  = EXT4_C2B(sbi, percpu_counter_sum_positive(fcc));
-               dirty_blocks = percpu_counter_sum_positive(dbc);
+       if (free_clusters - (nclusters + root_clusters + dirty_clusters) <
+                                       EXT4_FREECLUSTERS_WATERMARK) {
+               free_clusters  = percpu_counter_sum_positive(fcc);
+               dirty_clusters = percpu_counter_sum_positive(dcc);
        }
-       /* Check whether we have space after
-        * accounting for current dirty blocks & root reserved blocks.
+       /* Check whether we have space after accounting for current
+        * dirty clusters & root reserved clusters.
         */
-       if (free_blocks >= ((root_blocks + nblocks) + dirty_blocks))
+       if (free_clusters >= ((root_clusters + nclusters) + dirty_clusters))
                return 1;
 
-       /* Hm, nope.  Are (enough) root reserved blocks available? */
+       /* Hm, nope.  Are (enough) root reserved clusters available? */
        if (sbi->s_resuid == current_fsuid() ||
            ((sbi->s_resgid != 0) && in_group_p(sbi->s_resgid)) ||
            capable(CAP_SYS_RESOURCE) ||
                (flags & EXT4_MB_USE_ROOT_BLOCKS)) {
 
-               if (free_blocks >= (nblocks + dirty_blocks))
+               if (free_clusters >= (nclusters + dirty_clusters))
                        return 1;
        }
 
        return 0;
 }
 
-int ext4_claim_free_blocks(struct ext4_sb_info *sbi,
-                          s64 nblocks, unsigned int flags)
+int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
+                            s64 nclusters, unsigned int flags)
 {
-       if (ext4_has_free_blocks(sbi, nblocks, flags)) {
-               percpu_counter_add(&sbi->s_dirtyclusters_counter, nblocks);
+       if (ext4_has_free_clusters(sbi, nclusters, flags)) {
+               percpu_counter_add(&sbi->s_dirtyclusters_counter, nclusters);
                return 0;
        } else
                return -ENOSPC;
@@ -469,7 +477,7 @@ int ext4_claim_free_blocks(struct ext4_sb_info *sbi,
  */
 int ext4_should_retry_alloc(struct super_block *sb, int *retries)
 {
-       if (!ext4_has_free_blocks(EXT4_SB(sb), 1, 0) ||
+       if (!ext4_has_free_clusters(EXT4_SB(sb), 1, 0) ||
            (*retries)++ > 3 ||
            !EXT4_SB(sb)->s_journal)
                return 0;
@@ -556,7 +564,8 @@ ext4_fsblk_t ext4_count_free_clusters(struct super_block *sb)
                if (bitmap_bh == NULL)
                        continue;
 
-               x = ext4_count_free(bitmap_bh, sb->s_blocksize);
+               x = ext4_count_free(bitmap_bh->b_data,
+                                   EXT4_BLOCKS_PER_GROUP(sb) / 8);
                printk(KERN_DEBUG "group %u: stored = %d, counted = %u\n",
                        i, ext4_free_group_clusters(sb, gdp), x);
                bitmap_count += x;
@@ -564,7 +573,7 @@ ext4_fsblk_t ext4_count_free_clusters(struct super_block *sb)
        brelse(bitmap_bh);
        printk(KERN_DEBUG "ext4_count_free_clusters: stored = %llu"
               ", computed = %llu, %llu\n",
-              EXT4_B2C(sbi, ext4_free_blocks_count(es)),
+              EXT4_NUM_B2C(EXT4_SB(sb), ext4_free_blocks_count(es)),
               desc_count, bitmap_count);
        return bitmap_count;
 #else