On Jul 30, 2024 / 16:51, Shin'ichiro Kawasaki wrote:
> Since the kernel commit 73a74af0c72b ("dm: Improve zone resource limits
> handling"), zone resource limits (max open zones and max active zones)
> are propagated from target zoned devices to mapped devices. As the
> kernel commit message describes, the resource limit propagation shall
> follow the two rules below based on the number of sequential zones
> mapped by the targets:
>
> 1) For a target mapping an entire zoned block device, the limits for the
> target are set to the limits of the device.
> 2) For a target partially mapping a zoned block device, the number of
> mapped sequential zones is used to determine the limits: if the
> target maps more sequential write required zones than the device
> limits, then the limits of the device are used as-is. If the number
> of mapped sequential zones is lower than the limits, then we assume
> that the target has no limits (limits set to 0).
>
> Add a new test case to confirm that the resource limit propagation
> follows the rules. Prepare two zoned null_blk devices with different
> set ups: number of conventional zones, different max open zones and max
> active zones limits. Create variations of DMs using the null_blk devices
> and check if the max open zones and the max active zones have expected
> values.
>
> Suggested-by: Damien Le Moal <dlemoal@xxxxxxxxxx>
> Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@xxxxxxx>
> Signed-off-by: Damien Le Moal <dlemoal@xxxxxxxxxx>
FYI, I have applied the patch.
