Re: [PATCH v8 00/11] support non power of 2 zoned device

From: Bart Van Assche
Date: Wed Jul 27 2022 - 22:58:09 EST


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.