Re: expose dm-stripe target's topology I/O hints

[Mike Snitzer <snitzer@redhat.com>]

On Fri, Jul 10 2009 at  5:33pm -0400,
Mike Snitzer <snitzer@redhat.com> wrote:

> Add .io_hints to 'struct target_type' to allow the I/O hints portion of
> the 'struct queue_limits' to be set by each target.  Expose dm-stripe
> target's topology I/O hints.
> 
> NOTE: This patch makes use of blk_limits_io_min(); which will be
> upstream, via the block tree, in the near future.
> 
> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
> ---
> 
> diff --git a/drivers/md/dm-stripe.c b/drivers/md/dm-stripe.c
> index b240e85..9350566 100644
> --- a/drivers/md/dm-stripe.c
> +++ b/drivers/md/dm-stripe.c
> @@ -328,6 +328,16 @@ static int stripe_iterate_devices(struct dm_target *ti,
>  	return ret;
>  }
>  
> +static void stripe_io_hints(struct dm_target *ti,
> +			    struct queue_limits *limits)
> +{
> +	struct stripe_c *sc = ti->private;
> +	unsigned chunk_size = (sc->chunk_mask + 1) << 9;
> +
> +	blk_limits_io_min(chunk_size);
> +	limits->io_opt = chunk_size * sc->stripes;
> +}

The call to blk_limits_io_min() is missing the first queue_limits arg.

I'll send v2 of this patch.