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Date: Tue, 11 Jun 2024 17:02:28 +0900
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Subject: Re: [PATCH 14/26] block: move the nonrot flag to queue_limits
To: Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>
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From: Damien Le Moal <dlemoal@kernel.org>
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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