diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 6309a73d100a..888009bbec8f 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -5019,19 +5019,108 @@ static int decide_stripe_size(struct btrfs_fs_devices *fs_devices,
 	}
 }
 
+static int create_chunk(struct btrfs_trans_handle *trans,
+			struct alloc_chunk_ctl *ctl,
+			struct btrfs_device_info *devices_info)
+{
+	struct btrfs_fs_info *info = trans->fs_info;
+	struct map_lookup *map = NULL;
+	struct extent_map_tree *em_tree;
+	struct extent_map *em;
+	u64 start = ctl->start;
+	u64 type = ctl->type;
+	int ret;
+	int i;
+	int j;
+
+	map = kmalloc(map_lookup_size(ctl->num_stripes), GFP_NOFS);
+	if (!map)
+		return -ENOMEM;
+	map->num_stripes = ctl->num_stripes;
+
+	for (i = 0; i < ctl->ndevs; ++i) {
+		for (j = 0; j < ctl->dev_stripes; ++j) {
+			int s = i * ctl->dev_stripes + j;
+			map->stripes[s].dev = devices_info[i].dev;
+			map->stripes[s].physical = devices_info[i].dev_offset +
+						   j * ctl->stripe_size;
+		}
+	}
+	map->stripe_len = BTRFS_STRIPE_LEN;
+	map->io_align = BTRFS_STRIPE_LEN;
+	map->io_width = BTRFS_STRIPE_LEN;
+	map->type = type;
+	map->sub_stripes = ctl->sub_stripes;
+
+	trace_btrfs_chunk_alloc(info, map, start, ctl->chunk_size);
+
+	em = alloc_extent_map();
+	if (!em) {
+		kfree(map);
+		return -ENOMEM;
+	}
+	set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
+	em->map_lookup = map;
+	em->start = start;
+	em->len = ctl->chunk_size;
+	em->block_start = 0;
+	em->block_len = em->len;
+	em->orig_block_len = ctl->stripe_size;
+
+	em_tree = &info->mapping_tree;
+	write_lock(&em_tree->lock);
+	ret = add_extent_mapping(em_tree, em, 0);
+	if (ret) {
+		write_unlock(&em_tree->lock);
+		free_extent_map(em);
+		return ret;
+	}
+	write_unlock(&em_tree->lock);
+
+	ret = btrfs_make_block_group(trans, 0, type, start, ctl->chunk_size);
+	if (ret)
+		goto error_del_extent;
+
+	for (i = 0; i < map->num_stripes; i++) {
+		struct btrfs_device *dev = map->stripes[i].dev;
+
+		btrfs_device_set_bytes_used(dev,
+					    dev->bytes_used + ctl->stripe_size);
+		if (list_empty(&dev->post_commit_list))
+			list_add_tail(&dev->post_commit_list,
+				      &trans->transaction->dev_update_list);
+	}
+
+	atomic64_sub(ctl->stripe_size * map->num_stripes,
+		     &info->free_chunk_space);
+
+	free_extent_map(em);
+	check_raid56_incompat_flag(info, type);
+	check_raid1c34_incompat_flag(info, type);
+
+	return 0;
+
+error_del_extent:
+	write_lock(&em_tree->lock);
+	remove_extent_mapping(em_tree, em);
+	write_unlock(&em_tree->lock);
+
+	/* One for our allocation */
+	free_extent_map(em);
+	/* One for the tree reference */
+	free_extent_map(em);
+
+	return ret;
+}
+
 static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
 			       u64 start, u64 type)
 {
 	struct btrfs_fs_info *info = trans->fs_info;
 	struct btrfs_fs_devices *fs_devices = info->fs_devices;
-	struct map_lookup *map = NULL;
-	struct extent_map_tree *em_tree;
-	struct extent_map *em;
 	struct btrfs_device_info *devices_info = NULL;
 	struct alloc_chunk_ctl ctl;
 	int ret;
-	int i;
-	int j;
 
 	if (!alloc_profile_is_valid(type, 0)) {
 		ASSERT(0);
@@ -5061,94 +5150,15 @@ static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
 
 	ret = gather_device_info(fs_devices, &ctl, devices_info);
 	if (ret < 0)
-		goto error;
+		goto out;
 
 	ret = decide_stripe_size(fs_devices, &ctl, devices_info);
 	if (ret < 0)
-		goto error;
+		goto out;
 
-	map = kmalloc(map_lookup_size(ctl.num_stripes), GFP_NOFS);
-	if (!map) {
-		ret = -ENOMEM;
-		goto error;
-	}
+	ret = create_chunk(trans, &ctl, devices_info);
 
-	map->num_stripes = ctl.num_stripes;
-
-	for (i = 0; i < ctl.ndevs; ++i) {
-		for (j = 0; j < ctl.dev_stripes; ++j) {
-			int s = i * ctl.dev_stripes + j;
-			map->stripes[s].dev = devices_info[i].dev;
-			map->stripes[s].physical = devices_info[i].dev_offset +
-						   j * ctl.stripe_size;
-		}
-	}
-	map->stripe_len = BTRFS_STRIPE_LEN;
-	map->io_align = BTRFS_STRIPE_LEN;
-	map->io_width = BTRFS_STRIPE_LEN;
-	map->type = type;
-	map->sub_stripes = ctl.sub_stripes;
-
-	trace_btrfs_chunk_alloc(info, map, start, ctl.chunk_size);
-
-	em = alloc_extent_map();
-	if (!em) {
-		kfree(map);
-		ret = -ENOMEM;
-		goto error;
-	}
-	set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
-	em->map_lookup = map;
-	em->start = start;
-	em->len = ctl.chunk_size;
-	em->block_start = 0;
-	em->block_len = em->len;
-	em->orig_block_len = ctl.stripe_size;
-
-	em_tree = &info->mapping_tree;
-	write_lock(&em_tree->lock);
-	ret = add_extent_mapping(em_tree, em, 0);
-	if (ret) {
-		write_unlock(&em_tree->lock);
-		free_extent_map(em);
-		goto error;
-	}
-	write_unlock(&em_tree->lock);
-
-	ret = btrfs_make_block_group(trans, 0, type, start, ctl.chunk_size);
-	if (ret)
-		goto error_del_extent;
-
-	for (i = 0; i < map->num_stripes; i++) {
-		struct btrfs_device *dev = map->stripes[i].dev;
-
-		btrfs_device_set_bytes_used(dev,
-					    dev->bytes_used + ctl.stripe_size);
-		if (list_empty(&dev->post_commit_list))
-			list_add_tail(&dev->post_commit_list,
-				      &trans->transaction->dev_update_list);
-	}
-
-	atomic64_sub(ctl.stripe_size * map->num_stripes,
-		     &info->free_chunk_space);
-
-	free_extent_map(em);
-	check_raid56_incompat_flag(info, type);
-	check_raid1c34_incompat_flag(info, type);
-
-	kfree(devices_info);
-	return 0;
-
-error_del_extent:
-	write_lock(&em_tree->lock);
-	remove_extent_mapping(em_tree, em);
-	write_unlock(&em_tree->lock);
-
-	/* One for our allocation */
-	free_extent_map(em);
-	/* One for the tree reference */
-	free_extent_map(em);
-error:
+out:
 	kfree(devices_info);
 	return ret;
 }