Re: [PATCH 14/26] block: move the nonrot flag to queue_limits
- To: Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>
- Cc: Geert Uytterhoeven <geert@linux-m68k.org>, Richard Weinberger <richard@nod.at>, Philipp Reisner <philipp.reisner@linbit.com>, Lars Ellenberg <lars.ellenberg@linbit.com>, Christoph Böhmwalder <christoph.boehmwalder@linbit.com>, Josef Bacik <josef@toxicpanda.com>, Ming Lei <ming.lei@redhat.com>, "Michael S. Tsirkin" <mst@redhat.com>, Jason Wang <jasowang@redhat.com>, Roger Pau Monné <roger.pau@citrix.com>, Alasdair Kergon <agk@redhat.com>, Mike Snitzer <snitzer@kernel.org>, Mikulas Patocka <mpatocka@redhat.com>, Song Liu <song@kernel.org>, Yu Kuai <yukuai3@huawei.com>, Vineeth Vijayan <vneethv@linux.ibm.com>, "Martin K. Petersen" <martin.petersen@oracle.com>, linux-m68k@lists.linux-m68k.org, linux-um@lists.infradead.org, drbd-dev@lists.linbit.com, nbd@other.debian.org, linuxppc-dev@lists.ozlabs.org, ceph-devel@vger.kernel.org, virtualization@lists.linux.dev, xen-devel@lists.xenproject.org, linux-bcache@vger.kernel.org, dm-devel@lists.linux.dev, linux-raid@vger.kernel.org, linux-mmc@vger.kernel.org, linux-mtd@lists.infradead.org, nvdimm@lists.linux.dev, linux-nvme@lists.infradead.org, linux-s390@vger.kernel.org, linux-scsi@vger.kernel.org, linux-block@vger.kernel.org
- Subject: Re: [PATCH 14/26] block: move the nonrot flag to queue_limits
- From: Damien Le Moal <dlemoal@kernel.org>
- Date: Tue, 11 Jun 2024 17:02:28 +0900
- Message-id: <[🔎] 01366bae-699e-45dc-bad1-9541883a8b42@kernel.org>
- In-reply-to: <[🔎] 20240611051929.513387-15-hch@lst.de>
- References: <[🔎] 20240611051929.513387-1-hch@lst.de> <[🔎] 20240611051929.513387-15-hch@lst.de>
On 6/11/24 2:19 PM, Christoph Hellwig wrote:
> Move the norot flag into the queue_limits feature field so that it can be
s/norot/nonrot
> set atomically and all I/O is frozen when changing the flag.
and... -> with the queue frozen when... ?
>
> Use the chance to switch to defaulting to non-rotational and require
> the driver to opt into rotational, which matches the polarity of the
> sysfs interface.
>
> For the z2ram, ps3vram, 2x memstick, ubiblock and dcssblk the new
> rotational flag is not set as they clearly are not rotational despite
> this being a behavior change. There are some other drivers that
> unconditionally set the rotational flag to keep the existing behavior
> as they arguably can be used on rotational devices even if that is
> probably not their main use today (e.g. virtio_blk and drbd).
>
> The flag is automatically inherited in blk_stack_limits matching the
> existing behavior in dm and md.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
Other than that, looks good to me.
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
--
Damien Le Moal
Western Digital Research
Reply to: