@@ -212,6 +212,12 @@ static void check_block_bitmaps(e2fsck_t ctx)
int cmp_block = 0;
int redo_flag = 0;
blk64_t super_blk, old_desc_blk, new_desc_blk;
+ char *actual_buf, *bitmap_buf;
+
+ actual_buf = (char *) e2fsck_allocate_memory(ctx, fs->blocksize,
+ "actual bitmap buffer");
+ bitmap_buf = (char *) e2fsck_allocate_memory(ctx, fs->blocksize,
+ "bitmap block buffer");
clear_problem_context(&pctx);
free_array = (unsigned int *) e2fsck_allocate_memory(ctx,
@@ -259,11 +265,53 @@ redo_counts:
for (i = B2C(fs->super->s_first_data_block);
i < ext2fs_blocks_count(fs->super);
i += EXT2FS_CLUSTER_RATIO(fs)) {
+ int first_block_in_bg = (B2C(i) -
+ B2C(fs->super->s_first_data_block)) %
+ fs->super->s_clusters_per_group == 0;
+ int n, nbytes = fs->super->s_clusters_per_group / 8;
+
actual = ext2fs_fast_test_block_bitmap2(ctx->block_found_map, i);
+ /*
+ * Try to optimize pass5 by extracting a bitmap block
+ * as expected from what we have on disk, and then
+ * comparing the two. If they are identical, then
+ * update the free block counts and go on to the next
+ * block group. This is much faster than doing the
+ * individual bit-by-bit comparison. The one downside
+ * is that this doesn't work if we are asking e2fsck
+ * to do a discard operation.
+ */
+ if (!first_block_in_bg ||
+ (group == (int)fs->group_desc_count - 1) ||
+ (ctx->options & E2F_OPT_DISCARD))
+ goto no_optimize;
+
+ retval = ext2fs_get_block_bitmap_range2(ctx->block_found_map,
+ B2C(i), fs->super->s_clusters_per_group,
+ actual_buf);
+ if (retval)
+ goto no_optimize;
+ if (ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT))
+ memset(bitmap_buf, 0, nbytes);
+ else {
+ retval = ext2fs_get_block_bitmap_range2(fs->block_map,
+ B2C(i), fs->super->s_clusters_per_group,
+ bitmap_buf);
+ if (retval)
+ goto no_optimize;
+ }
+ if (memcmp(actual_buf, bitmap_buf, nbytes) != 0)
+ goto no_optimize;
+ n = ext2fs_bitcount(actual_buf, nbytes);
+ group_free = fs->super->s_clusters_per_group - n;
+ free_blocks += group_free;
+ i += fs->super->s_clusters_per_group - 1;
+ goto next_group;
+ no_optimize:
+
if (skip_group) {
- if ((B2C(i) - B2C(fs->super->s_first_data_block)) %
- fs->super->s_clusters_per_group == 0) {
+ if (first_block_in_bg) {
super_blk = 0;
old_desc_blk = 0;
new_desc_blk = 0;
@@ -401,6 +449,7 @@ redo_counts:
if (!bitmap && i >= first_free)
e2fsck_discard_blocks(ctx, first_free,
(i - first_free) + 1);
+ next_group:
first_free = ext2fs_blocks_count(fs->super);
free_array[group] = group_free;
@@ -475,6 +524,8 @@ redo_counts:
}
errout:
ext2fs_free_mem(&free_array);
+ ext2fs_free_mem(&actual_buf);
+ ext2fs_free_mem(&bitmap_buf);
}
static void check_inode_bitmaps(e2fsck_t ctx)