Re: [PATCH RFC 01/16] block: Add atomic write operations to request_queue limits

From: Mike Snitzer <snitzer@kernel.org>
To: John Garry <john.g.garry@oracle.com>
Cc: axboe@kernel.dk, kbusch@kernel.org, hch@lst.de, sagi@grimberg.me,
	martin.petersen@oracle.com, djwong@kernel.org,
	viro@zeniv.linux.org.uk, brauner@kernel.org, dchinner@redhat.com,
	jejb@linux.ibm.com, linux-block@vger.kernel.org,
	linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org,
	linux-scsi@vger.kernel.org, linux-xfs@vger.kernel.org,
	linux-fsdevel@vger.kernel.org,
	linux-security-module@vger.kernel.org, paul@paul-moore.com,
	jmorris@namei.org, serge@hallyn.com,
	Himanshu Madhani <himanshu.madhani@oracle.com>,
	dm-devel@redhat.com
Subject: Re: [PATCH RFC 01/16] block: Add atomic write operations to request_queue limits
Date: Mon, 8 May 2023 20:19:46 -0400	[thread overview]
Message-ID: <CAH6w=ay1NNxh=9mQv5PCcDi3OY0mgvRXO_0VrmKBLAd1dcUQqQ@mail.gmail.com> (raw)
In-Reply-To: <20230503183821.1473305-2-john.g.garry@oracle.com>

On Wed, May 3, 2023 at 2:40 PM John Garry <john.g.garry@oracle.com> wrote:
>
> From: Himanshu Madhani <himanshu.madhani@oracle.com>
>
> Add the following limits:
> - atomic_write_boundary
> - atomic_write_max_bytes
> - atomic_write_unit_max
> - atomic_write_unit_min
>
> Signed-off-by: Himanshu Madhani <himanshu.madhani@oracle.com>
> Signed-off-by: John Garry <john.g.garry@oracle.com>
> ---
>  Documentation/ABI/stable/sysfs-block | 42 +++++++++++++++++++++
>  block/blk-settings.c                 | 56 ++++++++++++++++++++++++++++
>  block/blk-sysfs.c                    | 33 ++++++++++++++++
>  include/linux/blkdev.h               | 23 ++++++++++++
>  4 files changed, 154 insertions(+)
>

...

> diff --git a/block/blk-settings.c b/block/blk-settings.c
> index 896b4654ab00..e21731715a12 100644
> --- a/block/blk-settings.c
> +++ b/block/blk-settings.c
> @@ -59,6 +59,9 @@ void blk_set_default_limits(struct queue_limits *lim)
>         lim->zoned = BLK_ZONED_NONE;
>         lim->zone_write_granularity = 0;
>         lim->dma_alignment = 511;
> +       lim->atomic_write_unit_min = lim->atomic_write_unit_max = 1;
> +       lim->atomic_write_max_bytes = 512;
> +       lim->atomic_write_boundary = 0;
>  }

Not seeing required changes to blk_set_stacking_limits() nor blk_stack_limits().

Sorry to remind you of DM and MD limits stacking requirements. ;)

Mike