btrfs: Replace owner argument in add_pinned_bytes with a boolean

add_pinned_bytes really cares whether the bytes being pinned are either
data or metadata. To that effect it checks whether the 'owner' argument
is less than BTRFS_FIRST_FREE_OBJECTID (256). This works because
owner can really have 2 types of values:

 a) For metadata extents it holds the level at which the parent is in
    the btree. This amounts to owner having the values 0-7

 b) In case of modifying data extents, owner is the inode number
    to which those extents belongs.

Let's make this more explicit byt converting the owner parameter to a
boolean value and either pass it directly when we know the type of
extents we are working with (i.e. in btrfs_free_tree_block). In cases
when the parent function can be called on both metadata/data extents
perform the check in the caller. This hopefully makes the interface
of add_pinned_bytes more intuitive.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/extent-tree.c

@@ -744,12 +744,12 @@ static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
 }
 
 static void add_pinned_bytes(struct btrfs_fs_info *fs_info, s64 num_bytes,
-			     u64 owner, u64 root_objectid)
+			     bool metadata, u64 root_objectid)
 {
 	struct btrfs_space_info *space_info;
 	u64 flags;
 
-	if (owner < BTRFS_FIRST_FREE_OBJECTID) {
+	if (metadata) {
 		if (root_objectid == BTRFS_CHUNK_TREE_OBJECTID)
 			flags = BTRFS_BLOCK_GROUP_SYSTEM;
 		else
@@ -2200,8 +2200,11 @@ int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
 						 &old_ref_mod, &new_ref_mod);
 	}
 
-	if (ret == 0 && old_ref_mod < 0 && new_ref_mod >= 0)
-		add_pinned_bytes(fs_info, -num_bytes, owner, root_objectid);
+	if (ret == 0 && old_ref_mod < 0 && new_ref_mod >= 0) {
+		bool metadata = owner < BTRFS_FIRST_FREE_OBJECTID;
+
+		add_pinned_bytes(fs_info, -num_bytes, metadata, root_objectid);
+	}
 
 	return ret;
 }
@@ -7266,7 +7269,7 @@ void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
 	}
 out:
 	if (pin)
-		add_pinned_bytes(fs_info, buf->len, btrfs_header_level(buf),
+		add_pinned_bytes(fs_info, buf->len, true,
 				 root->root_key.objectid);
 
 	if (last_ref) {
@@ -7320,8 +7323,11 @@ int btrfs_free_extent(struct btrfs_trans_handle *trans,
 						 &old_ref_mod, &new_ref_mod);
 	}
 
-	if (ret == 0 && old_ref_mod >= 0 && new_ref_mod < 0)
-		add_pinned_bytes(fs_info, num_bytes, owner, root_objectid);
+	if (ret == 0 && old_ref_mod >= 0 && new_ref_mod < 0) {
+		bool metadata = owner < BTRFS_FIRST_FREE_OBJECTID;
+
+		add_pinned_bytes(fs_info, num_bytes, metadata, root_objectid);
+	}
 
 	return ret;
 }