diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index f2373e70d9c8..2c21a7ede933 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -1035,10 +1035,11 @@ out_free:
 
 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
 static int convert_extent_item_v0(struct btrfs_trans_handle *trans,
-				  struct btrfs_root *root,
+				  struct btrfs_fs_info *fs_info,
 				  struct btrfs_path *path,
 				  u64 owner, u32 extra_size)
 {
+	struct btrfs_root *root = fs_info->extent_root;
 	struct btrfs_extent_item *item;
 	struct btrfs_extent_item_v0 *ei0;
 	struct btrfs_extent_ref_v0 *ref0;
@@ -1092,7 +1093,7 @@ static int convert_extent_item_v0(struct btrfs_trans_handle *trans,
 		return ret;
 	BUG_ON(ret); /* Corruption */
 
-	btrfs_extend_item(root->fs_info, path, new_size);
+	btrfs_extend_item(fs_info, path, new_size);
 
 	leaf = path->nodes[0];
 	item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
@@ -1151,12 +1152,13 @@ static int match_extent_data_ref(struct extent_buffer *leaf,
 }
 
 static noinline int lookup_extent_data_ref(struct btrfs_trans_handle *trans,
-					   struct btrfs_root *root,
+					   struct btrfs_fs_info *fs_info,
 					   struct btrfs_path *path,
 					   u64 bytenr, u64 parent,
 					   u64 root_objectid,
 					   u64 owner, u64 offset)
 {
+	struct btrfs_root *root = fs_info->extent_root;
 	struct btrfs_key key;
 	struct btrfs_extent_data_ref *ref;
 	struct extent_buffer *leaf;
@@ -1238,12 +1240,13 @@ fail:
 }
 
 static noinline int insert_extent_data_ref(struct btrfs_trans_handle *trans,
-					   struct btrfs_root *root,
+					   struct btrfs_fs_info *fs_info,
 					   struct btrfs_path *path,
 					   u64 bytenr, u64 parent,
 					   u64 root_objectid, u64 owner,
 					   u64 offset, int refs_to_add)
 {
+	struct btrfs_root *root = fs_info->extent_root;
 	struct btrfs_key key;
 	struct extent_buffer *leaf;
 	u32 size;
@@ -1317,7 +1320,7 @@ fail:
 }
 
 static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans,
-					   struct btrfs_root *root,
+					   struct btrfs_fs_info *fs_info,
 					   struct btrfs_path *path,
 					   int refs_to_drop, int *last_ref)
 {
@@ -1354,7 +1357,7 @@ static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans,
 	num_refs -= refs_to_drop;
 
 	if (num_refs == 0) {
-		ret = btrfs_del_item(trans, root, path);
+		ret = btrfs_del_item(trans, fs_info->extent_root, path);
 		*last_ref = 1;
 	} else {
 		if (key.type == BTRFS_EXTENT_DATA_REF_KEY)
@@ -1416,11 +1419,12 @@ static noinline u32 extent_data_ref_count(struct btrfs_path *path,
 }
 
 static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans,
-					  struct btrfs_root *root,
+					  struct btrfs_fs_info *fs_info,
 					  struct btrfs_path *path,
 					  u64 bytenr, u64 parent,
 					  u64 root_objectid)
 {
+	struct btrfs_root *root = fs_info->extent_root;
 	struct btrfs_key key;
 	int ret;
 
@@ -1449,7 +1453,7 @@ static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans,
 }
 
 static noinline int insert_tree_block_ref(struct btrfs_trans_handle *trans,
-					  struct btrfs_root *root,
+					  struct btrfs_fs_info *fs_info,
 					  struct btrfs_path *path,
 					  u64 bytenr, u64 parent,
 					  u64 root_objectid)
@@ -1466,7 +1470,8 @@ static noinline int insert_tree_block_ref(struct btrfs_trans_handle *trans,
 		key.offset = root_objectid;
 	}
 
-	ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
+	ret = btrfs_insert_empty_item(trans, fs_info->extent_root,
+				      path, &key, 0);
 	btrfs_release_path(path);
 	return ret;
 }
@@ -1524,14 +1529,14 @@ static int find_next_key(struct btrfs_path *path, int level,
  */
 static noinline_for_stack
 int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
-				 struct btrfs_root *root,
+				 struct btrfs_fs_info *fs_info,
 				 struct btrfs_path *path,
 				 struct btrfs_extent_inline_ref **ref_ret,
 				 u64 bytenr, u64 num_bytes,
 				 u64 parent, u64 root_objectid,
 				 u64 owner, u64 offset, int insert)
 {
-	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct btrfs_root *root = fs_info->extent_root;
 	struct btrfs_key key;
 	struct extent_buffer *leaf;
 	struct btrfs_extent_item *ei;
@@ -1614,7 +1619,7 @@ again:
 			err = -ENOENT;
 			goto out;
 		}
-		ret = convert_extent_item_v0(trans, root, path, owner,
+		ret = convert_extent_item_v0(trans, fs_info, path, owner,
 					     extra_size);
 		if (ret < 0) {
 			err = ret;
@@ -1716,7 +1721,7 @@ out:
  * helper to add new inline back ref
  */
 static noinline_for_stack
-void setup_inline_extent_backref(struct btrfs_root *root,
+void setup_inline_extent_backref(struct btrfs_fs_info *fs_info,
 				 struct btrfs_path *path,
 				 struct btrfs_extent_inline_ref *iref,
 				 u64 parent, u64 root_objectid,
@@ -1739,7 +1744,7 @@ void setup_inline_extent_backref(struct btrfs_root *root,
 	type = extent_ref_type(parent, owner);
 	size = btrfs_extent_inline_ref_size(type);
 
-	btrfs_extend_item(root->fs_info, path, size);
+	btrfs_extend_item(fs_info, path, size);
 
 	ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
 	refs = btrfs_extent_refs(leaf, ei);
@@ -1777,7 +1782,7 @@ void setup_inline_extent_backref(struct btrfs_root *root,
 }
 
 static int lookup_extent_backref(struct btrfs_trans_handle *trans,
-				 struct btrfs_root *root,
+				 struct btrfs_fs_info *fs_info,
 				 struct btrfs_path *path,
 				 struct btrfs_extent_inline_ref **ref_ret,
 				 u64 bytenr, u64 num_bytes, u64 parent,
@@ -1785,7 +1790,7 @@ static int lookup_extent_backref(struct btrfs_trans_handle *trans,
 {
 	int ret;
 
-	ret = lookup_inline_extent_backref(trans, root, path, ref_ret,
+	ret = lookup_inline_extent_backref(trans, fs_info, path, ref_ret,
 					   bytenr, num_bytes, parent,
 					   root_objectid, owner, offset, 0);
 	if (ret != -ENOENT)
@@ -1795,11 +1800,12 @@ static int lookup_extent_backref(struct btrfs_trans_handle *trans,
 	*ref_ret = NULL;
 
 	if (owner < BTRFS_FIRST_FREE_OBJECTID) {
-		ret = lookup_tree_block_ref(trans, root, path, bytenr, parent,
-					    root_objectid);
+		ret = lookup_tree_block_ref(trans, fs_info, path, bytenr,
+					    parent, root_objectid);
 	} else {
-		ret = lookup_extent_data_ref(trans, root, path, bytenr, parent,
-					     root_objectid, owner, offset);
+		ret = lookup_extent_data_ref(trans, fs_info, path, bytenr,
+					     parent, root_objectid, owner,
+					     offset);
 	}
 	return ret;
 }
@@ -1808,7 +1814,7 @@ static int lookup_extent_backref(struct btrfs_trans_handle *trans,
  * helper to update/remove inline back ref
  */
 static noinline_for_stack
-void update_inline_extent_backref(struct btrfs_root *root,
+void update_inline_extent_backref(struct btrfs_fs_info *fs_info,
 				  struct btrfs_path *path,
 				  struct btrfs_extent_inline_ref *iref,
 				  int refs_to_mod,
@@ -1866,14 +1872,14 @@ void update_inline_extent_backref(struct btrfs_root *root,
 			memmove_extent_buffer(leaf, ptr, ptr + size,
 					      end - ptr - size);
 		item_size -= size;
-		btrfs_truncate_item(root->fs_info, path, item_size, 1);
+		btrfs_truncate_item(fs_info, path, item_size, 1);
 	}
 	btrfs_mark_buffer_dirty(leaf);
 }
 
 static noinline_for_stack
 int insert_inline_extent_backref(struct btrfs_trans_handle *trans,
-				 struct btrfs_root *root,
+				 struct btrfs_fs_info *fs_info,
 				 struct btrfs_path *path,
 				 u64 bytenr, u64 num_bytes, u64 parent,
 				 u64 root_objectid, u64 owner,
@@ -1883,15 +1889,15 @@ int insert_inline_extent_backref(struct btrfs_trans_handle *trans,
 	struct btrfs_extent_inline_ref *iref;
 	int ret;
 
-	ret = lookup_inline_extent_backref(trans, root, path, &iref,
+	ret = lookup_inline_extent_backref(trans, fs_info, path, &iref,
 					   bytenr, num_bytes, parent,
 					   root_objectid, owner, offset, 1);
 	if (ret == 0) {
 		BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID);
-		update_inline_extent_backref(root, path, iref,
+		update_inline_extent_backref(fs_info, path, iref,
 					     refs_to_add, extent_op, NULL);
 	} else if (ret == -ENOENT) {
-		setup_inline_extent_backref(root, path, iref, parent,
+		setup_inline_extent_backref(fs_info, path, iref, parent,
 					    root_objectid, owner, offset,
 					    refs_to_add, extent_op);
 		ret = 0;
@@ -1900,7 +1906,7 @@ int insert_inline_extent_backref(struct btrfs_trans_handle *trans,
 }
 
 static int insert_extent_backref(struct btrfs_trans_handle *trans,
-				 struct btrfs_root *root,
+				 struct btrfs_fs_info *fs_info,
 				 struct btrfs_path *path,
 				 u64 bytenr, u64 parent, u64 root_objectid,
 				 u64 owner, u64 offset, int refs_to_add)
@@ -1908,10 +1914,10 @@ static int insert_extent_backref(struct btrfs_trans_handle *trans,
 	int ret;
 	if (owner < BTRFS_FIRST_FREE_OBJECTID) {
 		BUG_ON(refs_to_add != 1);
-		ret = insert_tree_block_ref(trans, root, path, bytenr,
+		ret = insert_tree_block_ref(trans, fs_info, path, bytenr,
 					    parent, root_objectid);
 	} else {
-		ret = insert_extent_data_ref(trans, root, path, bytenr,
+		ret = insert_extent_data_ref(trans, fs_info, path, bytenr,
 					     parent, root_objectid,
 					     owner, offset, refs_to_add);
 	}
@@ -1919,7 +1925,7 @@ static int insert_extent_backref(struct btrfs_trans_handle *trans,
 }
 
 static int remove_extent_backref(struct btrfs_trans_handle *trans,
-				 struct btrfs_root *root,
+				 struct btrfs_fs_info *fs_info,
 				 struct btrfs_path *path,
 				 struct btrfs_extent_inline_ref *iref,
 				 int refs_to_drop, int is_data, int *last_ref)
@@ -1928,14 +1934,14 @@ static int remove_extent_backref(struct btrfs_trans_handle *trans,
 
 	BUG_ON(!is_data && refs_to_drop != 1);
 	if (iref) {
-		update_inline_extent_backref(root, path, iref,
+		update_inline_extent_backref(fs_info, path, iref,
 					     -refs_to_drop, NULL, last_ref);
 	} else if (is_data) {
-		ret = remove_extent_data_ref(trans, root, path, refs_to_drop,
+		ret = remove_extent_data_ref(trans, fs_info, path, refs_to_drop,
 					     last_ref);
 	} else {
 		*last_ref = 1;
-		ret = btrfs_del_item(trans, root, path);
+		ret = btrfs_del_item(trans, fs_info->extent_root, path);
 	}
 	return ret;
 }
@@ -2117,9 +2123,9 @@ static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
 	path->reada = READA_FORWARD;
 	path->leave_spinning = 1;
 	/* this will setup the path even if it fails to insert the back ref */
-	ret = insert_inline_extent_backref(trans, fs_info->extent_root, path,
-					   bytenr, num_bytes, parent,
-					   root_objectid, owner, offset,
+	ret = insert_inline_extent_backref(trans, fs_info, path, bytenr,
+					   num_bytes, parent, root_objectid,
+					   owner, offset,
 					   refs_to_add, extent_op);
 	if ((ret < 0 && ret != -EAGAIN) || !ret)
 		goto out;
@@ -2143,9 +2149,8 @@ static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
 	path->reada = READA_FORWARD;
 	path->leave_spinning = 1;
 	/* now insert the actual backref */
-	ret = insert_extent_backref(trans, fs_info->extent_root,
-				    path, bytenr, parent, root_objectid,
-				    owner, offset, refs_to_add);
+	ret = insert_extent_backref(trans, fs_info, path, bytenr, parent,
+				    root_objectid, owner, offset, refs_to_add);
 	if (ret)
 		btrfs_abort_transaction(trans, ret);
 out:
@@ -2290,8 +2295,7 @@ again:
 	item_size = btrfs_item_size_nr(leaf, path->slots[0]);
 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
 	if (item_size < sizeof(*ei)) {
-		ret = convert_extent_item_v0(trans, fs_info->extent_root,
-					     path, (u64)-1, 0);
+		ret = convert_extent_item_v0(trans, fs_info, path, (u64)-1, 0);
 		if (ret < 0) {
 			err = ret;
 			goto out;
@@ -6841,7 +6845,7 @@ static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
 	if (is_data)
 		skinny_metadata = 0;
 
-	ret = lookup_extent_backref(trans, extent_root, path, &iref,
+	ret = lookup_extent_backref(trans, info, path, &iref,
 				    bytenr, num_bytes, parent,
 				    root_objectid, owner_objectid,
 				    owner_offset);
@@ -6873,8 +6877,8 @@ static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
 #endif
 		if (!found_extent) {
 			BUG_ON(iref);
-			ret = remove_extent_backref(trans, extent_root, path,
-						    NULL, refs_to_drop,
+			ret = remove_extent_backref(trans, info, path, NULL,
+						    refs_to_drop,
 						    is_data, &last_ref);
 			if (ret) {
 				btrfs_abort_transaction(trans, ret);
@@ -6949,8 +6953,8 @@ static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
 	if (item_size < sizeof(*ei)) {
 		BUG_ON(found_extent || extent_slot != path->slots[0]);
-		ret = convert_extent_item_v0(trans, extent_root, path,
-					     owner_objectid, 0);
+		ret = convert_extent_item_v0(trans, info, path, owner_objectid,
+					     0);
 		if (ret < 0) {
 			btrfs_abort_transaction(trans, ret);
 			goto out;
@@ -7017,7 +7021,7 @@ static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
 			btrfs_mark_buffer_dirty(leaf);
 		}
 		if (found_extent) {
-			ret = remove_extent_backref(trans, extent_root, path,
+			ret = remove_extent_backref(trans, info, path,
 						    iref, refs_to_drop,
 						    is_data, &last_ref);
 			if (ret) {
@@ -7415,12 +7419,11 @@ btrfs_release_block_group(struct btrfs_block_group_cache *cache,
  * If there is no suitable free space, we will record the max size of
  * the free space extent currently.
  */
-static noinline int find_free_extent(struct btrfs_root *orig_root,
+static noinline int find_free_extent(struct btrfs_fs_info *fs_info,
 				u64 ram_bytes, u64 num_bytes, u64 empty_size,
 				u64 hint_byte, struct btrfs_key *ins,
 				u64 flags, int delalloc)
 {
-	struct btrfs_fs_info *fs_info = orig_root->fs_info;
 	int ret = 0;
 	struct btrfs_root *root = fs_info->extent_root;
 	struct btrfs_free_cluster *last_ptr = NULL;
@@ -7948,7 +7951,7 @@ int btrfs_reserve_extent(struct btrfs_root *root, u64 ram_bytes,
 	flags = btrfs_get_alloc_profile(root, is_data);
 again:
 	WARN_ON(num_bytes < fs_info->sectorsize);
-	ret = find_free_extent(root, ram_bytes, num_bytes, empty_size,
+	ret = find_free_extent(fs_info, ram_bytes, num_bytes, empty_size,
 			       hint_byte, ins, flags, delalloc);
 	if (!ret && !is_data) {
 		btrfs_dec_block_group_reservations(fs_info, ins->objectid);