[PATCH 3/6] block: add a hard-readonly flag to struct gendisk

[Christoph Hellwig]

On Tue, Dec 08, 2020 at 06:22:11PM +0800, Ming Lei wrote:
> >  int bdev_read_only(struct block_device *bdev)
> >  {
> > -	return bdev->bd_read_only;
> > +	return bdev->bd_read_only ||
> > +		test_bit(GD_READ_ONLY, &bdev->bd_disk->state);
> >  }
> >  EXPORT_SYMBOL(bdev_read_only);
> 
> Maybe one inline version can be added for fast path(bio_check_ro()), and the approach
> is good:

I thought of that, but our header mess means it would have to be a macro.
I have a plan to reorganize the headers in the not too far future, at which
point this should become an inline.