[PATCH 5/9] btrfs: don't do backref modification for metadata for extent tree v2

[Josef Bacik <josef@toxicpanda.com>]

For extent tree v2 we will no longer track references for metadata in
the extent tree.  Make changes at the alloc and free sides so the proper
accounting is done but skip the extent tree modification parts.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/extent-tree.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 0c1988a7f845..369489394660 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -2957,7 +2957,6 @@ static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
 	struct btrfs_extent_item *ei;
 	struct btrfs_extent_inline_ref *iref;
 	int ret;
-	int is_data;
 	int extent_slot = 0;
 	int found_extent = 0;
 	int num_to_del = 1;
@@ -2966,6 +2965,11 @@ static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
 	u64 bytenr = node->bytenr;
 	u64 num_bytes = node->num_bytes;
 	bool skinny_metadata = btrfs_fs_incompat(info, SKINNY_METADATA);
+	bool is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
+
+	if (btrfs_fs_incompat(info, EXTENT_TREE_V2) && !is_data)
+		return do_free_extent_accounting(trans, bytenr, num_bytes,
+						 is_data);
 
 	extent_root = btrfs_extent_root(info, bytenr);
 	ASSERT(extent_root);
@@ -2974,8 +2978,6 @@ static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
 	if (!path)
 		return -ENOMEM;
 
-	is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
-
 	if (!is_data && refs_to_drop != 1) {
 		btrfs_crit(info,
 "invalid refs_to_drop, dropping more than 1 refs for tree block %llu refs_to_drop %u",
@@ -4706,6 +4708,9 @@ static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
 	u64 flags = extent_op->flags_to_set;
 	bool skinny_metadata = btrfs_fs_incompat(fs_info, SKINNY_METADATA);
 
+	if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2))
+		goto out;
+
 	ref = btrfs_delayed_node_to_tree_ref(node);
 
 	extent_key.objectid = node->bytenr;
@@ -4759,7 +4764,7 @@ static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
 
 	btrfs_mark_buffer_dirty(leaf);
 	btrfs_free_path(path);
-
+out:
 	return alloc_reserved_extent(trans, node->bytenr, fs_info->nodesize);
 }
 
-- 
2.26.3