static int nvme_tcp_init_connection()

in host/tcp.c [1249:1345]

• 85 lines of code
• 23 McCabe index (conditional complexity)

static int nvme_tcp_init_connection(struct nvme_tcp_queue *queue)
{
	struct nvme_tcp_icreq_pdu *icreq;
	struct nvme_tcp_icresp_pdu *icresp;
	struct msghdr msg = {};
	struct kvec iov;
	bool ctrl_hdgst, ctrl_ddgst;
	int ret;

	icreq = kzalloc(sizeof(*icreq), GFP_KERNEL);
	if (!icreq)
		return -ENOMEM;

	icresp = kzalloc(sizeof(*icresp), GFP_KERNEL);
	if (!icresp) {
		ret = -ENOMEM;
		goto free_icreq;
	}

	icreq->hdr.type = nvme_tcp_icreq;
	icreq->hdr.hlen = sizeof(*icreq);
	icreq->hdr.pdo = 0;
	icreq->hdr.plen = cpu_to_le32(icreq->hdr.hlen);
	icreq->pfv = cpu_to_le16(NVME_TCP_PFV_1_0);
	icreq->maxr2t = 0; /* single inflight r2t supported */
	icreq->hpda = 0; /* no alignment constraint */
	if (queue->hdr_digest)
		icreq->digest |= NVME_TCP_HDR_DIGEST_ENABLE;
	if (queue->data_digest)
		icreq->digest |= NVME_TCP_DATA_DIGEST_ENABLE;

	iov.iov_base = icreq;
	iov.iov_len = sizeof(*icreq);
	ret = kernel_sendmsg(queue->sock, &msg, &iov, 1, iov.iov_len);
	if (ret < 0)
		goto free_icresp;

	memset(&msg, 0, sizeof(msg));
	iov.iov_base = icresp;
	iov.iov_len = sizeof(*icresp);
	ret = kernel_recvmsg(queue->sock, &msg, &iov, 1,
			iov.iov_len, msg.msg_flags);
	if (ret < 0)
		goto free_icresp;

	ret = -EINVAL;
	if (icresp->hdr.type != nvme_tcp_icresp) {
		pr_err("queue %d: bad type returned %d\n",
			nvme_tcp_queue_id(queue), icresp->hdr.type);
		goto free_icresp;
	}

	if (le32_to_cpu(icresp->hdr.plen) != sizeof(*icresp)) {
		pr_err("queue %d: bad pdu length returned %d\n",
			nvme_tcp_queue_id(queue), icresp->hdr.plen);
		goto free_icresp;
	}

	if (icresp->pfv != NVME_TCP_PFV_1_0) {
		pr_err("queue %d: bad pfv returned %d\n",
			nvme_tcp_queue_id(queue), icresp->pfv);
		goto free_icresp;
	}

	ctrl_ddgst = !!(icresp->digest & NVME_TCP_DATA_DIGEST_ENABLE);
	if ((queue->data_digest && !ctrl_ddgst) ||
	    (!queue->data_digest && ctrl_ddgst)) {
		pr_err("queue %d: data digest mismatch host: %s ctrl: %s\n",
			nvme_tcp_queue_id(queue),
			queue->data_digest ? "enabled" : "disabled",
			ctrl_ddgst ? "enabled" : "disabled");
		goto free_icresp;
	}

	ctrl_hdgst = !!(icresp->digest & NVME_TCP_HDR_DIGEST_ENABLE);
	if ((queue->hdr_digest && !ctrl_hdgst) ||
	    (!queue->hdr_digest && ctrl_hdgst)) {
		pr_err("queue %d: header digest mismatch host: %s ctrl: %s\n",
			nvme_tcp_queue_id(queue),
			queue->hdr_digest ? "enabled" : "disabled",
			ctrl_hdgst ? "enabled" : "disabled");
		goto free_icresp;
	}

	if (icresp->cpda != 0) {
		pr_err("queue %d: unsupported cpda returned %d\n",
			nvme_tcp_queue_id(queue), icresp->cpda);
		goto free_icresp;
	}

	ret = 0;
free_icresp:
	kfree(icresp);
free_icreq:
	kfree(icreq);
	return ret;
}