If block group 0 is completely free, btrfs_read_block_groups will add extent [0, BTRFS_SUPER_INFO_OFFSET) to the free space cache.
Previous patch reveals a bug in add_new_free_space which may cause super block be added to the free space cache. This patch fixes it. Signed-off-by: Yan Zheng <[email protected]> --- diff -urp 1/fs/btrfs/extent-tree.c 2/fs/btrfs/extent-tree.c --- 1/fs/btrfs/extent-tree.c 2009-11-26 17:09:43.903551612 +0800 +++ 2/fs/btrfs/extent-tree.c 2009-11-26 17:14:11.898800726 +0800 @@ -195,6 +195,14 @@ static int exclude_super_stripes(struct int stripe_len; int i, nr, ret; + if (cache->key.objectid < BTRFS_SUPER_INFO_OFFSET) { + stripe_len = BTRFS_SUPER_INFO_OFFSET - cache->key.objectid; + cache->bytes_super += stripe_len; + ret = add_excluded_extent(root, cache->key.objectid, + stripe_len); + BUG_ON(ret); + } + for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) { bytenr = btrfs_sb_offset(i); ret = btrfs_rmap_block(&root->fs_info->mapping_tree, @@ -255,7 +263,7 @@ static u64 add_new_free_space(struct btr if (ret) break; - if (extent_start == start) { + if (extent_start <= start) { start = extent_end + 1; } else if (extent_start > start && extent_start < end) { size = extent_start - start; -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
