Re: [PATCH v6 0/6] block/md/dm: set chunk_sectors from stacked dev stripe size

[Damien Le Moal <dlemoal@kernel.org>]

On 7/11/25 5:09 PM, John Garry wrote:
> This value in io_min is used to configure any atomic write limit for the
> stacked device. The idea is that the atomic write unit max is a
> power-of-2 factor of the stripe size, and the stripe size is available
> in io_min.
> 
> Using io_min causes issues, as:
> a. it may be mutated
> b. the check for io_min being set for determining if we are dealing with
> a striped device is hard to get right, as reported in [0].
> 
> This series now sets chunk_sectors limit to share stripe size.

Hmm... chunk_sectors for a zoned device is the zone size. So is this all safe
if we are dealing with a zoned block device that also supports atomic writes ?
Not that I know of any such device, but better be safe, so maybe for now do not
enable atomic write support on zoned devices ?



-- 
Damien Le Moal
Western Digital Research