btrfs: use btrfs_root_id() where not done yet

A few more remaining cases where we can use the helper.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>

Author: kdave

fs/btrfs/extent-tree.c

@@ -5554,7 +5554,7 @@ static int check_ref_exists(struct btrfs_trans_handle *trans,
 		goto again;
 	}
 
-	exists = btrfs_find_delayed_tree_ref(head, root->root_key.objectid, parent);
+	exists = btrfs_find_delayed_tree_ref(head, btrfs_root_id(root), parent);
 	mutex_unlock(&head->mutex);
 out:
 	spin_unlock(&delayed_refs->lock);

fs/btrfs/extent_io.c

@@ -1704,7 +1704,7 @@ static int extent_writepage(struct folio *folio, struct btrfs_bio_ctrl *bio_ctrl
 		WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
 		btrfs_err_rl(fs_info,
 	"root %lld ino %llu folio %llu is marked dirty without notifying the fs",
-			     inode->root->root_key.objectid,
+			     btrfs_root_id(inode->root),
 			     btrfs_ino(inode), folio_pos(folio));
 		ret = -EUCLEAN;
 		goto done;

fs/btrfs/inode.c

@@ -2881,7 +2881,7 @@ int btrfs_writepage_cow_fixup(struct folio *folio)
 		DEBUG_WARN();
 		btrfs_err_rl(fs_info,
 	"root %lld ino %llu folio %llu is marked dirty without notifying the fs",
-			     BTRFS_I(inode)->root->root_key.objectid,
+			     btrfs_root_id(BTRFS_I(inode)->root),
 			     btrfs_ino(BTRFS_I(inode)),
 			     folio_pos(folio));
 		return -EUCLEAN;
@@ -8023,7 +8023,7 @@ static int btrfs_getattr(struct mnt_idmap *idmap,
 	generic_fillattr(idmap, request_mask, inode, stat);
 	stat->dev = BTRFS_I(inode)->root->anon_dev;
 
-	stat->subvol = BTRFS_I(inode)->root->root_key.objectid;
+	stat->subvol = btrfs_root_id(BTRFS_I(inode)->root);
 	stat->result_mask |= STATX_SUBVOL;
 
 	spin_lock(&BTRFS_I(inode)->lock);