[PATCH 2/6] nvme: read the subsystem NQN from Identify Controller

[Johannes Thumshirn]

On 06/15/2017 06:34 PM, Christoph Hellwig wrote:
> +	/* Generate a "fake" NQN per Figure 254 in NVMe 1.3 + ECN 001 */
> +	snprintf(ctrl->subnqn, NVMF_NQN_SIZE,
> +		"nqn.2014.08.org.nvmexpress:%4x%4x",
> +		le16_to_cpu(id->vid), le16_to_cpu(id->ssvid));
> +	memcpy(ctrl->subnqn + 35, id->sn, sizeof(id->sn));
> +	memcpy(ctrl->subnqn + 55, id->mn, sizeof(id->mn));
> +	memset(ctrl->subnqn + 95, 0, sizeof(ctrl->subnqn) - 95);

Is there a chance we can do this with a bit less magic values? We can
calculate all of the offsets.

Something like:

off = snprintf(ctrl->subnqn, NVMF_NQN_SIZE,
	"nqn.2014.08.org.nvmexpress:%4x%4x",
	le16_to_cpu(id->vid), le16_to_cpu(id->ssvid));
memcpy(ctrl->subnqn + off, id->sn, sizeof(id->sn));
off += sizeof(id->sn);
memcpy(ctrl->subnqn + off, id->mn, sizeof(id->mn));
off += sizeof(id->mn);
memset(ctrl->subnqn + off, 0, sizeof(ctrl->subnqn) - off);

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Johannes Thumshirn                                          Storage
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