[dm-devel] [PATCH v3 02/10] block: Introduce queue limits for copy-offload support

[Luis Chamberlain]

On Thu, Feb 17, 2022 at 10:16:21AM +0000, Chaitanya Kulkarni wrote:
> On 2/17/22 1:07 AM, Luis Chamberlain wrote:
> >> diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
> >> index efed3820cbf7..792e6d556589 100644
> >> --- a/include/linux/blkdev.h
> >> +++ b/include/linux/blkdev.h
> >> @@ -254,6 +254,13 @@ struct queue_limits {
> >>   	unsigned int		discard_alignment;
> >>   	unsigned int		zone_write_granularity;
> >>   
> >> +	unsigned long		max_hw_copy_sectors;
> >> +	unsigned long		max_copy_sectors;
> >> +	unsigned int		max_hw_copy_range_sectors;
> >> +	unsigned int		max_copy_range_sectors;
> >> +	unsigned short		max_hw_copy_nr_ranges;
> >> +	unsigned short		max_copy_nr_ranges;
> > 
> > Before limits start growing more.. I wonder if we should just
> > stuff hw offload stuff to its own struct within queue_limits.
> > 
> > Christoph?
> > 
> 
> Potentially use a pointer to structure and maybe make it configurable,

Did you mean to make queue limits local or for hw offload and make that
a pointer? If so that seems odd because even for hw copy offload we
still need the other limits no?

So what I meant was that struct queue_limits seems to be getting large,
and that hw copy offload seems like an example use case where we should
probably use a separate struct for it. And while at it, well, start
adding kdocs for these things, because, there's tons of things which
could use kdoc love.

> although I'm not sure about the later part, I'll let Christoph decide
> that.

  Luis