iscsi_tcp.c

		iscsi_set_param(cls_conn, param, buf, buflen);
		if (session->max_r2t & (session->max_r2t - 1))
			session->max_r2t = roundup_pow_of_two(session->max_r2t);
		if (iscsi_r2tpool_alloc(session))
			return -ENOMEM;
		break;
	default:
		return iscsi_set_param(cls_conn, param, buf, buflen);
	}

	return 0;
}

static int
iscsi_tcp_conn_get_param(struct iscsi_cls_conn *cls_conn,
			 enum iscsi_param param, char *buf)
{
	struct iscsi_conn *conn = cls_conn->dd_data;
	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
	struct inet_sock *inet;
	struct ipv6_pinfo *np;
	struct sock *sk;
	int len;

	switch(param) {
	case ISCSI_PARAM_CONN_PORT:
		mutex_lock(&conn->xmitmutex);
		if (!tcp_conn->sock) {
			mutex_unlock(&conn->xmitmutex);
			return -EINVAL;
		}

		inet = inet_sk(tcp_conn->sock->sk);
		len = sprintf(buf, "%hu\n", be16_to_cpu(inet->dport));
		mutex_unlock(&conn->xmitmutex);
		break;
	case ISCSI_PARAM_CONN_ADDRESS:
		mutex_lock(&conn->xmitmutex);
		if (!tcp_conn->sock) {
			mutex_unlock(&conn->xmitmutex);
			return -EINVAL;
		}

		sk = tcp_conn->sock->sk;
		if (sk->sk_family == PF_INET) {
			inet = inet_sk(sk);
			len = sprintf(buf, "%u.%u.%u.%u\n",
				      NIPQUAD(inet->daddr));
		} else {
			np = inet6_sk(sk);
			len = sprintf(buf,
				"%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
				NIP6(np->daddr));
		}
		mutex_unlock(&conn->xmitmutex);
		break;
	default:
		return iscsi_conn_get_param(cls_conn, param, buf);
	}

	return len;
}

static void
iscsi_conn_get_stats(struct iscsi_cls_conn *cls_conn, struct iscsi_stats *stats)
{
	struct iscsi_conn *conn = cls_conn->dd_data;
	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;

	stats->txdata_octets = conn->txdata_octets;
	stats->rxdata_octets = conn->rxdata_octets;
	stats->scsicmd_pdus = conn->scsicmd_pdus_cnt;
	stats->dataout_pdus = conn->dataout_pdus_cnt;
	stats->scsirsp_pdus = conn->scsirsp_pdus_cnt;
	stats->datain_pdus = conn->datain_pdus_cnt;
	stats->r2t_pdus = conn->r2t_pdus_cnt;
	stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt;
	stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt;
	stats->custom_length = 3;
	strcpy(stats->custom[0].desc, "tx_sendpage_failures");
	stats->custom[0].value = tcp_conn->sendpage_failures_cnt;
	strcpy(stats->custom[1].desc, "rx_discontiguous_hdr");
	stats->custom[1].value = tcp_conn->discontiguous_hdr_cnt;
	strcpy(stats->custom[2].desc, "eh_abort_cnt");
	stats->custom[2].value = conn->eh_abort_cnt;
}

static struct iscsi_cls_session *
iscsi_tcp_session_create(struct iscsi_transport *iscsit,
			 struct scsi_transport_template *scsit,
			 uint32_t initial_cmdsn, uint32_t *hostno)
{
	struct iscsi_cls_session *cls_session;
	struct iscsi_session *session;
	uint32_t hn;
	int cmd_i;

	cls_session = iscsi_session_setup(iscsit, scsit,
					 sizeof(struct iscsi_tcp_cmd_task),
					 sizeof(struct iscsi_tcp_mgmt_task),
					 initial_cmdsn, &hn);
	if (!cls_session)
		return NULL;
	*hostno = hn;

	session = class_to_transport_session(cls_session);
	for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
		struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
		struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;

		ctask->hdr = &tcp_ctask->hdr;
	}

	for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
		struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
		struct iscsi_tcp_mgmt_task *tcp_mtask = mtask->dd_data;

		mtask->hdr = &tcp_mtask->hdr;
	}

	if (iscsi_r2tpool_alloc(class_to_transport_session(cls_session)))
		goto r2tpool_alloc_fail;

	return cls_session;

r2tpool_alloc_fail:
	iscsi_session_teardown(cls_session);
	return NULL;
}

static void iscsi_tcp_session_destroy(struct iscsi_cls_session *cls_session)
{
	iscsi_r2tpool_free(class_to_transport_session(cls_session));
	iscsi_session_teardown(cls_session);
}

static struct scsi_host_template iscsi_sht = {
	.name			= "iSCSI Initiator over TCP/IP",
	.queuecommand           = iscsi_queuecommand,
	.change_queue_depth	= iscsi_change_queue_depth,
	.can_queue		= ISCSI_XMIT_CMDS_MAX - 1,
	.sg_tablesize		= ISCSI_SG_TABLESIZE,
	.cmd_per_lun		= ISCSI_DEF_CMD_PER_LUN,
	.eh_abort_handler       = iscsi_eh_abort,
	.eh_host_reset_handler	= iscsi_eh_host_reset,
	.use_clustering         = DISABLE_CLUSTERING,
	.proc_name		= "iscsi_tcp",
	.this_id		= -1,
};

static struct iscsi_transport iscsi_tcp_transport = {
	.owner			= THIS_MODULE,
	.name			= "tcp",
	.caps			= CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST
				  | CAP_DATADGST,
	.param_mask		= ISCSI_MAX_RECV_DLENGTH |
				  ISCSI_MAX_XMIT_DLENGTH |
				  ISCSI_HDRDGST_EN |
				  ISCSI_DATADGST_EN |
				  ISCSI_INITIAL_R2T_EN |
				  ISCSI_MAX_R2T |
				  ISCSI_IMM_DATA_EN |
				  ISCSI_FIRST_BURST |
				  ISCSI_MAX_BURST |
				  ISCSI_PDU_INORDER_EN |
				  ISCSI_DATASEQ_INORDER_EN |
				  ISCSI_ERL |
				  ISCSI_CONN_PORT |
				  ISCSI_CONN_ADDRESS |
				  ISCSI_EXP_STATSN |
				  ISCSI_PERSISTENT_PORT |
				  ISCSI_PERSISTENT_ADDRESS |
				  ISCSI_TARGET_NAME |
				  ISCSI_TPGT,
	.host_template		= &iscsi_sht,
	.conndata_size		= sizeof(struct iscsi_conn),
	.max_conn		= 1,
	.max_cmd_len		= ISCSI_TCP_MAX_CMD_LEN,
	/* session management */
	.create_session		= iscsi_tcp_session_create,
	.destroy_session	= iscsi_tcp_session_destroy,
	/* connection management */
	.create_conn		= iscsi_tcp_conn_create,
	.bind_conn		= iscsi_tcp_conn_bind,
	.destroy_conn		= iscsi_tcp_conn_destroy,
	.set_param		= iscsi_conn_set_param,
	.get_conn_param		= iscsi_tcp_conn_get_param,
	.get_session_param	= iscsi_session_get_param,
	.start_conn		= iscsi_conn_start,
	.stop_conn		= iscsi_tcp_conn_stop,
	/* IO */
	.send_pdu		= iscsi_conn_send_pdu,
	.get_stats		= iscsi_conn_get_stats,
	.init_cmd_task		= iscsi_tcp_cmd_init,
	.init_mgmt_task		= iscsi_tcp_mgmt_init,
	.xmit_cmd_task		= iscsi_tcp_ctask_xmit,
	.xmit_mgmt_task		= iscsi_tcp_mtask_xmit,
	.cleanup_cmd_task	= iscsi_tcp_cleanup_ctask,
	/* recovery */
	.session_recovery_timedout = iscsi_session_recovery_timedout,
};

static int __init
iscsi_tcp_init(void)
{
	if (iscsi_max_lun < 1) {
		printk(KERN_ERR "iscsi_tcp: Invalid max_lun value of %u\n",
		       iscsi_max_lun);
		return -EINVAL;
	}
	iscsi_tcp_transport.max_lun = iscsi_max_lun;

	if (!iscsi_register_transport(&iscsi_tcp_transport))
		return -ENODEV;

	return 0;
}

static void __exit
iscsi_tcp_exit(void)
{
	iscsi_unregister_transport(&iscsi_tcp_transport);
}

module_init(iscsi_tcp_init);
module_exit(iscsi_tcp_exit);