Commit 06b2331f authored by Yan, Zheng's avatar Yan, Zheng Committed by Chris Mason
Browse files

Btrfs: don't add extent 0 to the free space cache v2 



If block group 0 is completely free, btrfs_read_block_groups will
add extent [0, BTRFS_SUPER_INFO_OFFSET) to the free space cache.

Signed-off-by: default avatarYan Zheng <zheng.yan@oracle.com>
Signed-off-by: default avatarChris Mason <chris.mason@oracle.com>
parent 86b9f2ec

fs/btrfs/extent-tree.c

+9 −1
Original line number Diff line number Diff line
@@ -195,6 +195,14 @@ static int exclude_super_stripes(struct btrfs_root *root, 
	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 btrfs_block_group_cache *block_group, 
		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;