btrfs: don't pass parent objectid to btrfs_new_inode() explicitly

For everything other than a subvolume root inode, we get the parent
objectid from the parent directory. For the subvolume root inode, the
parent objectid is the same as the inode's objectid. We can find this
within btrfs_new_inode() instead of passing it.
Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/inode.c

@@ -6090,8 +6090,7 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
 				     struct user_namespace *mnt_userns,
 				     struct inode *dir,
 				     const char *name, int name_len,
-				     u64 ref_objectid, u64 objectid,
-				     umode_t mode, u64 *index)
+				     u64 objectid, umode_t mode, u64 *index)
 {
 	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct inode *inode;
@@ -6177,7 +6176,10 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
 		 */
 		key[1].objectid = objectid;
 		key[1].type = BTRFS_INODE_REF_KEY;
-		key[1].offset = ref_objectid;
+		if (dir)
+			key[1].offset = btrfs_ino(BTRFS_I(dir));
+		else
+			key[1].offset = objectid;
 
 		sizes[1] = name_len + sizeof(*ref);
 	}
@@ -6375,7 +6377,7 @@ static int btrfs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
 
 	inode = btrfs_new_inode(trans, root, mnt_userns, dir,
 			dentry->d_name.name, dentry->d_name.len,
-			btrfs_ino(BTRFS_I(dir)), objectid, mode, &index);
+			objectid, mode, &index);
 	if (IS_ERR(inode)) {
 		err = PTR_ERR(inode);
 		inode = NULL;
@@ -6439,7 +6441,7 @@ static int btrfs_create(struct user_namespace *mnt_userns, struct inode *dir,
 
 	inode = btrfs_new_inode(trans, root, mnt_userns, dir,
 			dentry->d_name.name, dentry->d_name.len,
-			btrfs_ino(BTRFS_I(dir)), objectid, mode, &index);
+			objectid, mode, &index);
 	if (IS_ERR(inode)) {
 		err = PTR_ERR(inode);
 		inode = NULL;
@@ -6584,7 +6586,7 @@ static int btrfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
 
 	inode = btrfs_new_inode(trans, root, mnt_userns, dir,
 			dentry->d_name.name, dentry->d_name.len,
-			btrfs_ino(BTRFS_I(dir)), objectid,
+			objectid,
 			S_IFDIR | mode, &index);
 	if (IS_ERR(inode)) {
 		err = PTR_ERR(inode);
@@ -8769,7 +8771,7 @@ int btrfs_create_subvol_root(struct btrfs_trans_handle *trans,
 		return err;
 
 	inode = btrfs_new_inode(trans, new_root, mnt_userns, NULL, "..", 2,
-				ino, ino,
+				ino,
 				S_IFDIR | (~current_umask() & S_IRWXUGO),
 				&index);
 	if (IS_ERR(inode))
@@ -9282,7 +9284,6 @@ static int btrfs_whiteout_for_rename(struct btrfs_trans_handle *trans,
 	inode = btrfs_new_inode(trans, root, mnt_userns, dir,
 				dentry->d_name.name,
 				dentry->d_name.len,
-				btrfs_ino(BTRFS_I(dir)),
 				objectid,
 				S_IFCHR | WHITEOUT_MODE,
 				&index);
@@ -9776,7 +9777,7 @@ static int btrfs_symlink(struct user_namespace *mnt_userns, struct inode *dir,
 
 	inode = btrfs_new_inode(trans, root, mnt_userns, dir,
 				dentry->d_name.name, dentry->d_name.len,
-				btrfs_ino(BTRFS_I(dir)), objectid,
+				objectid,
 				S_IFLNK | S_IRWXUGO, &index);
 	if (IS_ERR(inode)) {
 		err = PTR_ERR(inode);
@@ -10122,7 +10123,7 @@ static int btrfs_tmpfile(struct user_namespace *mnt_userns, struct inode *dir,
 		goto out;
 
 	inode = btrfs_new_inode(trans, root, mnt_userns, dir, NULL, 0,
-			btrfs_ino(BTRFS_I(dir)), objectid, mode, &index);
+			objectid, mode, &index);
 	if (IS_ERR(inode)) {
 		ret = PTR_ERR(inode);
 		inode = NULL;