[dm-devel] [PATCH v8 00/11] support non power of 2 zoned device

[Bart Van Assche]

On 7/27/22 18:52, Damien Le Moal wrote:
> On 7/28/22 08:19, Bart Van Assche wrote:
>> On 7/27/22 09:22, Pankaj Raghav wrote:
>>> This series adds support to npo2 zoned devices in the block and nvme
>>> layer and a new **dm target** is added: dm-po2z-target. This new
>>> target will be initially used for filesystems such as btrfs and
>>> f2fs that does not have native npo2 zone support.
>>
>> Should any SCSI changes be included in this patch series? From sd_zbc.c:
>>
>> 	if (!is_power_of_2(zone_blocks)) {
>> 		sd_printk(KERN_ERR, sdkp,
>> 			  "Zone size %llu is not a power of two.\n",
>> 			  zone_blocks);
>> 		return -EINVAL;
>> 	}
> 
> There are no non-power of 2 SMR drives on the market and no plans to have
> any as far as I know. Users want power of 2 zone size. So I think it is
> better to leave sd_zbc & scsi_debug as is for now.

Zoned UFS devices will support ZBC and may have a zone size that is not 
a power of two.

Thanks,

Bart.