On Sat, Apr 26, 2025 at 10:10:55AM +0800, Lizhi Xu wrote:
> +static int loop_check_backing_file(struct file *file, blk_mode_t mode, bool change)
> +{
> + if (!file->f_op->read_iter)
> + return -EINVAL;
> +
> + if (((file->f_mode & FMODE_WRITE) ||
> + (!change && (mode & BLK_OPEN_WRITE))) &&
> + (!file->f_op->write_iter))
> + return -EINVAL;
This looks a bit odd. Both callers have the open struct file, so
we should be able to check f_mode for both cases and not need the
change flag as far as I can tell. Or did I miss something/
If for some reason we could not pass the fmode, the helper is
probably not all that useful.
