From: Qu Wenruo <wqu@suse.com>
Date: Tue, 5 May 2020 07:58:22 +0800
Git-commit: 97f4728af88822ddd13941c3ac84a4ce3a9ff823
Patch-mainline: 5.8-rc1
References: bsc#1176019
Subject: [PATCH] btrfs: block-group: refactor how we insert a block group item

Currently the block group item insert is pretty straight forward, fill
the block group item structure and insert it into extent tree.

However the incoming skinny block group feature is going to change this,
so this patch will refactor insertion into a new function,
insert_block_group_item(), to make the incoming feature easier to add.

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: Filipe Manana <fdmanana@suse.com>
---
 fs/btrfs/block-group.c | 41 +++++++++++++++++++++++++----------------
 1 file changed, 25 insertions(+), 16 deletions(-)

diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c
index af990f82448f..0b5849f46835 100644
--- a/fs/btrfs/block-group.c
+++ b/fs/btrfs/block-group.c
@@ -2071,13 +2071,32 @@ int btrfs_read_block_groups(struct btrfs_fs_info *info)
 	return ret;
 }
 
+static int insert_block_group_item(struct btrfs_trans_handle *trans,
+				   struct btrfs_block_group *block_group)
+{
+	struct btrfs_fs_info *fs_info = trans->fs_info;
+	struct btrfs_block_group_item bgi;
+	struct btrfs_root *root;
+	struct btrfs_key key;
+
+	spin_lock(&block_group->lock);
+	btrfs_set_stack_block_group_used(&bgi, block_group->used);
+	btrfs_set_stack_block_group_chunk_objectid(&bgi,
+				BTRFS_FIRST_CHUNK_TREE_OBJECTID);
+	btrfs_set_stack_block_group_flags(&bgi, block_group->flags);
+	key.objectid = block_group->start;
+	key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
+	key.offset = block_group->length;
+	spin_unlock(&block_group->lock);
+
+	root = fs_info->extent_root;
+	return btrfs_insert_item(trans, root, &key, &bgi, sizeof(bgi));
+}
+
 void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans)
 {
 	struct btrfs_fs_info *fs_info = trans->fs_info;
 	struct btrfs_block_group *block_group;
-	struct btrfs_root *extent_root = fs_info->extent_root;
-	struct btrfs_block_group_item item;
-	struct btrfs_key key;
 	int ret = 0;
 
 	if (!trans->can_flush_pending_bgs)
@@ -2090,21 +2109,11 @@ void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans)
 		if (ret)
 			goto next;
 
-		spin_lock(&block_group->lock);
-		btrfs_set_stack_block_group_used(&item, block_group->used);
-		btrfs_set_stack_block_group_chunk_objectid(&item,
-				BTRFS_FIRST_CHUNK_TREE_OBJECTID);
-		btrfs_set_stack_block_group_flags(&item, block_group->flags);
-		key.objectid = block_group->start;
-		key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
-		key.offset = block_group->length;
-		spin_unlock(&block_group->lock);
-
-		ret = btrfs_insert_item(trans, extent_root, &key, &item,
-					sizeof(item));
+		ret = insert_block_group_item(trans, block_group);
 		if (ret)
 			btrfs_abort_transaction(trans, ret);
-		ret = btrfs_finish_chunk_alloc(trans, key.objectid, key.offset);
+		ret = btrfs_finish_chunk_alloc(trans, block_group->start,
+					block_group->length);
 		if (ret)
 			btrfs_abort_transaction(trans, ret);
 		add_block_group_free_space(trans, block_group);
-- 
2.26.2