static int nvme_init_identify()

in host/core.c [2921:3068]

• 114 lines of code
• 26 McCabe index (conditional complexity)

static int nvme_init_identify(struct nvme_ctrl *ctrl)
{
	struct nvme_id_ctrl *id;
	u32 max_hw_sectors;
	bool prev_apst_enabled;
	int ret;

	ret = nvme_identify_ctrl(ctrl, &id);
	if (ret) {
		dev_err(ctrl->device, "Identify Controller failed (%d)\n", ret);
		return -EIO;
	}

	if (id->lpa & NVME_CTRL_LPA_CMD_EFFECTS_LOG) {
		ret = nvme_get_effects_log(ctrl, NVME_CSI_NVM, &ctrl->effects);
		if (ret < 0)
			goto out_free;
	}

	if (!(ctrl->ops->flags & NVME_F_FABRICS))
		ctrl->cntlid = le16_to_cpu(id->cntlid);

	if (!ctrl->identified) {
		unsigned int i;

		ret = nvme_init_subsystem(ctrl, id);
		if (ret)
			goto out_free;

		/*
		 * Check for quirks.  Quirk can depend on firmware version,
		 * so, in principle, the set of quirks present can change
		 * across a reset.  As a possible future enhancement, we
		 * could re-scan for quirks every time we reinitialize
		 * the device, but we'd have to make sure that the driver
		 * behaves intelligently if the quirks change.
		 */
		for (i = 0; i < ARRAY_SIZE(core_quirks); i++) {
			if (quirk_matches(id, &core_quirks[i]))
				ctrl->quirks |= core_quirks[i].quirks;
		}
	}

	if (force_apst && (ctrl->quirks & NVME_QUIRK_NO_DEEPEST_PS)) {
		dev_warn(ctrl->device, "forcibly allowing all power states due to nvme_core.force_apst -- use at your own risk\n");
		ctrl->quirks &= ~NVME_QUIRK_NO_DEEPEST_PS;
	}

	ctrl->crdt[0] = le16_to_cpu(id->crdt1);
	ctrl->crdt[1] = le16_to_cpu(id->crdt2);
	ctrl->crdt[2] = le16_to_cpu(id->crdt3);

	ctrl->oacs = le16_to_cpu(id->oacs);
	ctrl->oncs = le16_to_cpu(id->oncs);
	ctrl->mtfa = le16_to_cpu(id->mtfa);
	ctrl->oaes = le32_to_cpu(id->oaes);
	ctrl->wctemp = le16_to_cpu(id->wctemp);
	ctrl->cctemp = le16_to_cpu(id->cctemp);

	atomic_set(&ctrl->abort_limit, id->acl + 1);
	ctrl->vwc = id->vwc;
	if (id->mdts)
		max_hw_sectors = nvme_mps_to_sectors(ctrl, id->mdts);
	else
		max_hw_sectors = UINT_MAX;
	ctrl->max_hw_sectors =
		min_not_zero(ctrl->max_hw_sectors, max_hw_sectors);

	nvme_set_queue_limits(ctrl, ctrl->admin_q);
	ctrl->sgls = le32_to_cpu(id->sgls);
	ctrl->kas = le16_to_cpu(id->kas);
	ctrl->max_namespaces = le32_to_cpu(id->mnan);
	ctrl->ctratt = le32_to_cpu(id->ctratt);

	if (id->rtd3e) {
		/* us -> s */
		u32 transition_time = le32_to_cpu(id->rtd3e) / USEC_PER_SEC;

		ctrl->shutdown_timeout = clamp_t(unsigned int, transition_time,
						 shutdown_timeout, 60);

		if (ctrl->shutdown_timeout != shutdown_timeout)
			dev_info(ctrl->device,
				 "Shutdown timeout set to %u seconds\n",
				 ctrl->shutdown_timeout);
	} else
		ctrl->shutdown_timeout = shutdown_timeout;

	ctrl->npss = id->npss;
	ctrl->apsta = id->apsta;
	prev_apst_enabled = ctrl->apst_enabled;
	if (ctrl->quirks & NVME_QUIRK_NO_APST) {
		if (force_apst && id->apsta) {
			dev_warn(ctrl->device, "forcibly allowing APST due to nvme_core.force_apst -- use at your own risk\n");
			ctrl->apst_enabled = true;
		} else {
			ctrl->apst_enabled = false;
		}
	} else {
		ctrl->apst_enabled = id->apsta;
	}
	memcpy(ctrl->psd, id->psd, sizeof(ctrl->psd));

	if (ctrl->ops->flags & NVME_F_FABRICS) {
		ctrl->icdoff = le16_to_cpu(id->icdoff);
		ctrl->ioccsz = le32_to_cpu(id->ioccsz);
		ctrl->iorcsz = le32_to_cpu(id->iorcsz);
		ctrl->maxcmd = le16_to_cpu(id->maxcmd);

		/*
		 * In fabrics we need to verify the cntlid matches the
		 * admin connect
		 */
		if (ctrl->cntlid != le16_to_cpu(id->cntlid)) {
			dev_err(ctrl->device,
				"Mismatching cntlid: Connect %u vs Identify "
				"%u, rejecting\n",
				ctrl->cntlid, le16_to_cpu(id->cntlid));
			ret = -EINVAL;
			goto out_free;
		}

		if (!nvme_discovery_ctrl(ctrl) && !ctrl->kas) {
			dev_err(ctrl->device,
				"keep-alive support is mandatory for fabrics\n");
			ret = -EINVAL;
			goto out_free;
		}
	} else {
		ctrl->hmpre = le32_to_cpu(id->hmpre);
		ctrl->hmmin = le32_to_cpu(id->hmmin);
		ctrl->hmminds = le32_to_cpu(id->hmminds);
		ctrl->hmmaxd = le16_to_cpu(id->hmmaxd);
	}

	ret = nvme_mpath_init_identify(ctrl, id);
	if (ret < 0)
		goto out_free;

	if (ctrl->apst_enabled && !prev_apst_enabled)
		dev_pm_qos_expose_latency_tolerance(ctrl->device);
	else if (!ctrl->apst_enabled && prev_apst_enabled)
		dev_pm_qos_hide_latency_tolerance(ctrl->device);

out_free:
	kfree(id);
	return ret;
}