Re: [PATCH v2 2/6] block/nbd-client: drop max_block restriction from discard

[Eric Blake <eblake@redhat.com>]

On 4/1/20 10:01 AM, Vladimir Sementsov-Ogievskiy wrote:
> NBD spec is updated, so that max_block doesn't relate to
> NBD_CMD_TRIM. So, drop the restriction.
> 
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> ---
>   block/nbd.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)

Reviewed-by: Eric Blake <eblake@redhat.com>

I might tweak the commit message of 1/6 and here to call out the NBD 
spec commit id (nbd.git 9f30fedb), but that doesn't change the patch proper.

> 
> diff --git a/block/nbd.c b/block/nbd.c
> index d4d518a780..4ac23c8f62 100644
> --- a/block/nbd.c
> +++ b/block/nbd.c
> @@ -1955,7 +1955,7 @@ static void nbd_refresh_limits(BlockDriverState *bs, Error **errp)
>       }
>   
>       bs->bl.request_alignment = min;
> -    bs->bl.max_pdiscard = max;
> +    bs->bl.max_pdiscard = QEMU_ALIGN_DOWN(INT_MAX, min);
>       bs->bl.max_pwrite_zeroes = max;
>       bs->bl.max_transfer = max;
>   
> 

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3226
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