[PATCH V11 2/4] nvmet: add ZBD over ZNS backend support

[Chaitanya Kulkarni]

>> +
>> +bool nvmet_bdev_zns_enable(struct nvmet_ns *ns)
>> +{
>> +	if (nvmet_bdev_has_conv_zones(ns->bdev))
>> +		return false;
>> +
>> +	ns->blksize_shift = blksize_bits(bdev_physical_block_size(ns->bdev));
> Shouldn't this be using logical block size ? Otherwise, zsze calculation in
> nvmet_execute_identify_cns_cs_ns() could be wrong.

Okay, will send out V12 with that fix.

>> +
>> +	if (!nvmet_zns_update_zasl(ns))
>> +		return false;
>> +
>> +	return !(get_capacity(ns->bdev->bd_disk) &
>> +			(bdev_zone_sectors(ns->bdev) - 1));
>> +}
>> +
>> +void nvmet_execute_identify_cns_cs_ctrl(struct nvmet_req *req)
>>
>> +
>> +void nvmet_bdev_execute_zone_mgmt_recv(struct nvmet_req *req)
>> +{
>> +	sector_t sect = nvmet_lba_to_sect(req->ns, req->cmd->zmr.slba);
>> +	u32 bufsize = (le32_to_cpu(req->cmd->zmr.numd) + 1) << 2;
>> +	struct nvmet_report_zone_data data = { .ns = req->ns };
>> +	unsigned int nr_zones;
>> +	int reported_zones;
>> +	u16 status;
>> +
>> +	status = nvmet_bdev_zns_checks(req);
>> +	if (status)
>> +		goto out;
>> +
>> +	data.rz = __vmalloc(bufsize, GFP_KERNEL | __GFP_NORETRY | __GFP_ZERO);
>> +	if (!data.rz) {
>> +		status = NVME_SC_INTERNAL;
>> +		goto out;
>> +	}
>> +
>> +	nr_zones = (bufsize - sizeof(struct nvme_zone_report)) /
>> +			sizeof(struct nvme_zone_descriptor);
> What if nr_zones is 0 ? This should be failed.

blkdev_report_zones() already handles that check. I thinkthe error condition
below blkdev_report_zones() should include<= 0 case instead of just <.

Will send V12 with the <= fix.

>
>> +	reported_zones = blkdev_report_zones(req->ns->bdev, sect, nr_zones,
>> +					     nvmet_bdev_report_zone_cb, &data);
>> +	if (reported_zones < 0) {
>> +		status = NVME_SC_INTERNAL;
>> +		goto out_free_report_zones;
>> +	}
>> +
>> +	data.rz->nr_zones = cpu_to_le64(reported_zones);
>> +
>> +	status = nvmet_copy_to_sgl(req, 0, data.rz, bufsize);
>> +
>> +out_free_report_zones:
>> +	kvfree(data.rz);
>> +out:
>> +	nvmet_req_complete(req, status);
>> +}
>> +
>>