[PATCH 5.7 006/112] btrfs: block-group: refactor how we delete one block group item

Greg Kroah-Hartman
2020-07-07T15:23:33Z

From: Qu Wenruo <wqu@suse.com>

[ Upstream commit 7357623a7f4beb4ac76005f8fac9fc0230f9a67e ]

When deleting a block group item, it's pretty straight forward, just
delete the item pointed by the key. However it will not be that
straight-forward for incoming skinny block group item.

So refactor the block group item deletion into a new function,
remove_block_group_item(), also to make the already lengthy
btrfs_remove_block_group() a little shorter.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/btrfs/block-group.c | 37 +++++++++++++++++++++++++------------
1 file changed, 25 insertions(+), 12 deletions(-)

diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c
index 0c17f18b47940..d80857d00b0fb 100644
--- a/fs/btrfs/block-group.c
+++ b/fs/btrfs/block-group.c
@@ -863,11 +863,34 @@ static void clear_incompat_bg_bits(struct btrfs_fs_info *fs_info, u64 flags)
}
}

+static int remove_block_group_item(struct btrfs_trans_handle *trans,
+ struct btrfs_path *path,
+ struct btrfs_block_group *block_group)
+{
+ struct btrfs_fs_info *fs_info = trans->fs_info;
+ struct btrfs_root *root;
+ struct btrfs_key key;
+ int ret;
+
+ root = fs_info->extent_root;
+ key.objectid = block_group->start;
+ key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
+ key.offset = block_group->length;
+
+ ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
+ if (ret > 0)
+ ret = -ENOENT;
+ if (ret < 0)
+ return ret;
+
+ ret = btrfs_del_item(trans, root, path);
+ return ret;
+}
+
int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
u64 group_start, struct extent_map *em)
{
struct btrfs_fs_info *fs_info = trans->fs_info;
- struct btrfs_root *root = fs_info->extent_root;
struct btrfs_path *path;
struct btrfs_block_group *block_group;
struct btrfs_free_cluster *cluster;
@@ -1068,10 +1091,6 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,

spin_unlock(&block_group->space_info->lock);

- key.objectid = block_group->start;
- key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
- key.offset = block_group->length;
-
mutex_lock(&fs_info->chunk_mutex);
spin_lock(&block_group->lock);
block_group->removed = 1;
@@ -1107,16 +1126,10 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
if (ret)
goto out;

- ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
- if (ret > 0)
- ret = -EIO;
+ ret = remove_block_group_item(trans, path, block_group);
if (ret < 0)
goto out;

- ret = btrfs_del_item(trans, root, path);
- if (ret)
- goto out;
-
if (remove_em) {
struct extent_map_tree *em_tree;

--
2.25.1