[PATCH v9 37/41] btrfs: split alloc_log_tree()

[Naohiro Aota <naohiro.aota@xxxxxxx>]

This is a preparation for the next patch. This commit split
alloc_log_tree() to allocating tree structure part (remains in
alloc_log_tree()) and allocating tree node part (moved in
btrfs_alloc_log_tree_node()). The latter part is also exported to be used
in the next patch.

Signed-off-by: Johannes Thumshirn <johannes.thumshirn@xxxxxxx>
Signed-off-by: Naohiro Aota <naohiro.aota@xxxxxxx>
---
 fs/btrfs/disk-io.c | 31 +++++++++++++++++++++++++------
 fs/btrfs/disk-io.h |  2 ++
 2 files changed, 27 insertions(+), 6 deletions(-)

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 2b30ef8a7034..70885f3d3321 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1211,7 +1211,6 @@ static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
 					 struct btrfs_fs_info *fs_info)
 {
 	struct btrfs_root *root;
-	struct extent_buffer *leaf;
 
 	root = btrfs_alloc_root(fs_info, BTRFS_TREE_LOG_OBJECTID, GFP_NOFS);
 	if (!root)
@@ -1221,6 +1220,14 @@ static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
 	root->root_key.type = BTRFS_ROOT_ITEM_KEY;
 	root->root_key.offset = BTRFS_TREE_LOG_OBJECTID;
 
+	return root;
+}
+
+int btrfs_alloc_log_tree_node(struct btrfs_trans_handle *trans,
+			      struct btrfs_root *root)
+{
+	struct extent_buffer *leaf;
+
 	/*
 	 * DON'T set SHAREABLE bit for log trees.
 	 *
@@ -1233,26 +1240,31 @@ static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
 
 	leaf = btrfs_alloc_tree_block(trans, root, 0, BTRFS_TREE_LOG_OBJECTID,
 			NULL, 0, 0, 0, BTRFS_NESTING_NORMAL);
-	if (IS_ERR(leaf)) {
-		btrfs_put_root(root);
-		return ERR_CAST(leaf);
-	}
+	if (IS_ERR(leaf))
+		return PTR_ERR(leaf);
 
 	root->node = leaf;
 
 	btrfs_mark_buffer_dirty(root->node);
 	btrfs_tree_unlock(root->node);
-	return root;
+
+	return 0;
 }
 
 int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
 			     struct btrfs_fs_info *fs_info)
 {
 	struct btrfs_root *log_root;
+	int ret;
 
 	log_root = alloc_log_tree(trans, fs_info);
 	if (IS_ERR(log_root))
 		return PTR_ERR(log_root);
+	ret = btrfs_alloc_log_tree_node(trans, log_root);
+	if (ret) {
+		kfree(log_root);
+		return ret;
+	}
 	WARN_ON(fs_info->log_root_tree);
 	fs_info->log_root_tree = log_root;
 	return 0;
@@ -1264,11 +1276,18 @@ int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
 	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_root *log_root;
 	struct btrfs_inode_item *inode_item;
+	int ret;
 
 	log_root = alloc_log_tree(trans, fs_info);
 	if (IS_ERR(log_root))
 		return PTR_ERR(log_root);
 
+	ret = btrfs_alloc_log_tree_node(trans, log_root);
+	if (ret) {
+		btrfs_put_root(log_root);
+		return ret;
+	}
+
 	log_root->last_trans = trans->transid;
 	log_root->root_key.offset = root->root_key.objectid;
 
diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h
index fee69ced58b4..b82ae3711c42 100644
--- a/fs/btrfs/disk-io.h
+++ b/fs/btrfs/disk-io.h
@@ -115,6 +115,8 @@ blk_status_t btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
 			extent_submit_bio_start_t *submit_bio_start);
 blk_status_t btrfs_submit_bio_done(void *private_data, struct bio *bio,
 			  int mirror_num);
+int btrfs_alloc_log_tree_node(struct btrfs_trans_handle *trans,
+			      struct btrfs_root *root);
 int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
 			     struct btrfs_fs_info *fs_info);
 int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
-- 
2.27.0