iscsi-target: Initial traditional TCP conversion to iscsit_transport

This patch performs the initial conversion of existing traditional iscsi
to use iscsit_transport API callers.  This includes:

- iscsi-np cleanups for iscsit_transport_type
- Add iscsi-np transport calls w/ ->iscsit_setup_up() and ->iscsit_free_np()
- Convert login thread process context to use ->iscsit_accept_np() for
  connections with pre-allocated struct iscsi_conn
- Convert existing socket accept code to iscsit_accept_np()
- Convert login RX/TX callers to use ->iscsit_get_login_rx() and
  ->iscsit_put_login_tx() to exchange request/response PDUs
- Convert existing socket login RX/TX calls into iscsit_get_login_rx()
  and iscsit_put_login_tx()
- Change iscsit_close_connection() to invoke ->iscsit_free_conn() +
  iscsit_put_transport() calls.
- Add iscsit_register_transport() + iscsit_unregister_transport() calls
  to module init/exit

v4 changes:

- Add missing iscsit_put_transport() call in iscsi_target_setup_login_socket()
  failure case

v2 changes:

- Update module init/exit to use register_transport() + unregister_transport()

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

1 files changed, 289 insertions, 127 deletions

diff --git a/drivers/target/iscsi/iscsi_target_login.c b/drivers/target/iscsi/iscsi_target_login.c
index 2535d4d46c0e..0de5c47d1c81 100644
--- a/drivers/target/iscsi/iscsi_target_login.c
+++ b/drivers/target/iscsi/iscsi_target_login.c
@@ -39,8 +39,39 @@
 #include "iscsi_target.h"
 #include "iscsi_target_parameters.h"
 
-static int iscsi_login_init_conn(struct iscsi_conn *conn)
+#include <target/iscsi/iscsi_transport.h>
+
+static struct iscsi_login *iscsi_login_init_conn(struct iscsi_conn *conn)
 {
+	struct iscsi_login *login;
+
+	login = kzalloc(sizeof(struct iscsi_login), GFP_KERNEL);
+	if (!login) {
+		pr_err("Unable to allocate memory for struct iscsi_login.\n");
+		return NULL;
+	}
+	login->conn = conn;
+	login->first_request = 1;
+
+	login->req_buf = kzalloc(MAX_KEY_VALUE_PAIRS, GFP_KERNEL);
+	if (!login->req_buf) {
+		pr_err("Unable to allocate memory for response buffer.\n");
+		goto out_login;
+	}
+
+	login->rsp_buf = kzalloc(MAX_KEY_VALUE_PAIRS, GFP_KERNEL);
+	if (!login->rsp_buf) {
+		pr_err("Unable to allocate memory for request buffer.\n");
+		goto out_req_buf;
+	}
+
+	conn->conn_ops = kzalloc(sizeof(struct iscsi_conn_ops), GFP_KERNEL);
+	if (!conn->conn_ops) {
+		pr_err("Unable to allocate memory for"
+			" struct iscsi_conn_ops.\n");
+		goto out_rsp_buf;
+	}
+
 	init_waitqueue_head(&conn->queues_wq);
 	INIT_LIST_HEAD(&conn->conn_list);
 	INIT_LIST_HEAD(&conn->conn_cmd_list);
@@ -62,10 +93,21 @@ static int iscsi_login_init_conn(struct iscsi_conn *conn)
 
 	if (!zalloc_cpumask_var(&conn->conn_cpumask, GFP_KERNEL)) {
 		pr_err("Unable to allocate conn->conn_cpumask\n");
-		return -ENOMEM;
+		goto out_conn_ops;
 	}
+	conn->conn_login = login;
 
-	return 0;
+	return login;
+
+out_conn_ops:
+	kfree(conn->conn_ops);
+out_rsp_buf:
+	kfree(login->rsp_buf);
+out_req_buf:
+	kfree(login->req_buf);
+out_login:
+	kfree(login);
+	return NULL;
 }
 
 /*
@@ -573,10 +615,13 @@ int iscsi_login_post_auth_non_zero_tsih(
 
 static void iscsi_post_login_start_timers(struct iscsi_conn *conn)
 {
+#warning FIXME: Reenable iscsit_start_nopin_timer
+#if 0
 	struct iscsi_session *sess = conn->sess;
 
 	if (!sess->sess_ops->SessionType)
 		iscsit_start_nopin_timer(conn);
+#endif
 }
 
 static int iscsi_post_login_handler(
@@ -632,7 +677,13 @@ static int iscsi_post_login_handler(
 		spin_unlock_bh(&sess->conn_lock);
 
 		iscsi_post_login_start_timers(conn);
-		iscsi_activate_thread_set(conn, ts);
+
+		if (conn->conn_transport == ISCSI_TCP) {
+			iscsi_activate_thread_set(conn, ts);
+		} else {
+			printk("Not calling iscsi_activate_thread_set....\n");
+			dump_stack();
+		}
 		/*
 		 * Determine CPU mask to ensure connection's RX and TX kthreads
 		 * are scheduled on the same CPU.
@@ -761,11 +812,11 @@ static void iscsi_stop_login_thread_timer(struct iscsi_np *np)
 	spin_unlock_bh(&np->np_thread_lock);
 }
 
-int iscsi_target_setup_login_socket(
+int iscsit_setup_np(
 	struct iscsi_np *np,
 	struct __kernel_sockaddr_storage *sockaddr)
 {
-	struct socket *sock;
+	struct socket *sock = NULL;
 	int backlog = 5, ret, opt = 0, len;
 
 	switch (np->np_network_transport) {
@@ -781,15 +832,15 @@ int iscsi_target_setup_login_socket(
 		np->np_ip_proto = IPPROTO_SCTP;
 		np->np_sock_type = SOCK_SEQPACKET;
 		break;
-	case ISCSI_IWARP_TCP:
-	case ISCSI_IWARP_SCTP:
-	case ISCSI_INFINIBAND:
 	default:
 		pr_err("Unsupported network_transport: %d\n",
 				np->np_network_transport);
 		return -EINVAL;
 	}
 
+	np->np_ip_proto = IPPROTO_TCP;
+	np->np_sock_type = SOCK_STREAM;
+
 	ret = sock_create(sockaddr->ss_family, np->np_sock_type,
 			np->np_ip_proto, &sock);
 	if (ret < 0) {
@@ -853,7 +904,6 @@ int iscsi_target_setup_login_socket(
 	}
 
 	return 0;
-
 fail:
 	np->np_socket = NULL;
 	if (sock)
@@ -861,21 +911,170 @@ fail:
 	return ret;
 }
 
+int iscsi_target_setup_login_socket(
+	struct iscsi_np *np,
+	struct __kernel_sockaddr_storage *sockaddr)
+{
+	struct iscsit_transport *t;
+	int rc;
+
+	t = iscsit_get_transport(np->np_network_transport);
+	if (!t)
+		return -EINVAL;
+
+	rc = t->iscsit_setup_np(np, sockaddr);
+	if (rc < 0) {
+		iscsit_put_transport(t);
+		return rc;
+	}
+
+	np->np_transport = t;
+	printk("Set np->np_transport to %p -> %s\n", np->np_transport,
+				np->np_transport->name);
+	return 0;
+}
+
+int iscsit_accept_np(struct iscsi_np *np, struct iscsi_conn *conn)
+{
+	struct socket *new_sock, *sock = np->np_socket;
+	struct sockaddr_in sock_in;
+	struct sockaddr_in6 sock_in6;
+	int rc, err;
+
+	rc = kernel_accept(sock, &new_sock, 0);
+	if (rc < 0)
+		return rc;
+
+	conn->sock = new_sock;
+	conn->login_family = np->np_sockaddr.ss_family;
+	printk("iSCSI/TCP: Setup conn->sock from new_sock: %p\n", new_sock);
+
+	if (np->np_sockaddr.ss_family == AF_INET6) {
+		memset(&sock_in6, 0, sizeof(struct sockaddr_in6));
+
+		rc = conn->sock->ops->getname(conn->sock,
+				(struct sockaddr *)&sock_in6, &err, 1);
+		if (!rc) {
+			snprintf(conn->login_ip, sizeof(conn->login_ip), "%pI6c",
+				&sock_in6.sin6_addr.in6_u);
+			conn->login_port = ntohs(sock_in6.sin6_port);
+		}
+
+		rc = conn->sock->ops->getname(conn->sock,
+				(struct sockaddr *)&sock_in6, &err, 0);
+		if (!rc) {
+			snprintf(conn->local_ip, sizeof(conn->local_ip), "%pI6c",
+				&sock_in6.sin6_addr.in6_u);
+			conn->local_port = ntohs(sock_in6.sin6_port);
+		}
+	} else {
+		memset(&sock_in, 0, sizeof(struct sockaddr_in));
+
+		rc = conn->sock->ops->getname(conn->sock,
+				(struct sockaddr *)&sock_in, &err, 1);
+		if (!rc) {
+			sprintf(conn->login_ip, "%pI4",
+					&sock_in.sin_addr.s_addr);
+			conn->login_port = ntohs(sock_in.sin_port);
+		}
+
+		rc = conn->sock->ops->getname(conn->sock,
+				(struct sockaddr *)&sock_in, &err, 0);
+		if (!rc) {
+			sprintf(conn->local_ip, "%pI4",
+					&sock_in.sin_addr.s_addr);
+			conn->local_port = ntohs(sock_in.sin_port);
+		}
+	}
+
+	return 0;
+}
+
+int iscsit_get_login_rx(struct iscsi_conn *conn, struct iscsi_login *login)
+{
+	struct iscsi_login_req *login_req;
+	u32 padding = 0, payload_length;
+
+	if (iscsi_login_rx_data(conn, login->req, ISCSI_HDR_LEN) < 0)
+		return -1;
+
+	login_req = (struct iscsi_login_req *)login->req;
+	payload_length	= ntoh24(login_req->dlength);
+	padding = ((-payload_length) & 3);
+
+	pr_debug("Got Login Command, Flags 0x%02x, ITT: 0x%08x,"
+		" CmdSN: 0x%08x, ExpStatSN: 0x%08x, CID: %hu, Length: %u\n",
+		login_req->flags, login_req->itt, login_req->cmdsn,
+		login_req->exp_statsn, login_req->cid, payload_length);
+	/*
+	 * Setup the initial iscsi_login values from the leading
+	 * login request PDU.
+	 */
+	if (login->first_request) {
+		login_req = (struct iscsi_login_req *)login->req;
+		login->leading_connection = (!login_req->tsih) ? 1 : 0;
+		login->current_stage	=
+			(login_req->flags & ISCSI_FLAG_LOGIN_CURRENT_STAGE_MASK) >> 2;
+		login->version_min	= login_req->min_version;
+		login->version_max	= login_req->max_version;
+		memcpy(login->isid, login_req->isid, 6);
+		login->cmd_sn		= be32_to_cpu(login_req->cmdsn);
+		login->init_task_tag	= login_req->itt;
+		login->initial_exp_statsn = be32_to_cpu(login_req->exp_statsn);
+		login->cid		= be16_to_cpu(login_req->cid);
+		login->tsih		= be16_to_cpu(login_req->tsih);
+	}
+
+	if (iscsi_target_check_login_request(conn, login) < 0)
+		return -1;
+
+	memset(login->req_buf, 0, MAX_KEY_VALUE_PAIRS);
+	if (iscsi_login_rx_data(conn, login->req_buf,
+				payload_length + padding) < 0)
+		return -1;
+
+	return 0;
+}
+
+int iscsit_put_login_tx(struct iscsi_conn *conn, struct iscsi_login *login,
+			u32 length)
+{
+	if (iscsi_login_tx_data(conn, login->rsp, login->rsp_buf, length) < 0)
+		return -1;
+
+	return 0;
+}
+
+static int
+iscsit_conn_set_transport(struct iscsi_conn *conn, struct iscsit_transport *t)
+{
+	int rc;
+
+	if (!t->owner) {
+		conn->conn_transport = t;
+		return 0;
+	}
+
+	rc = try_module_get(t->owner);
+	if (!rc) {
+		pr_err("try_module_get() failed for %s\n", t->name);
+		return -EINVAL;
+	}
+
+	conn->conn_transport = t;
+	return 0;
+}
+
 static int __iscsi_target_login_thread(struct iscsi_np *np)
 {
-	u8 buffer[ISCSI_HDR_LEN], iscsi_opcode, zero_tsih = 0;
-	int err, ret = 0, stop;
+	u8 *buffer, zero_tsih = 0;
+	int ret = 0, rc, stop;
 	struct iscsi_conn *conn = NULL;
 	struct iscsi_login *login;
 	struct iscsi_portal_group *tpg = NULL;
-	struct socket *new_sock, *sock;
-	struct kvec iov;
 	struct iscsi_login_req *pdu;
-	struct sockaddr_in sock_in;
-	struct sockaddr_in6 sock_in6;
 
 	flush_signals(current);
-	sock = np->np_socket;
 
 	spin_lock_bh(&np->np_thread_lock);
 	if (np->np_thread_state == ISCSI_NP_THREAD_RESET) {
@@ -886,75 +1085,76 @@ static int __iscsi_target_login_thread(struct iscsi_np *np)
 	}
 	spin_unlock_bh(&np->np_thread_lock);
 
-	if (kernel_accept(sock, &new_sock, 0) < 0) {
-		spin_lock_bh(&np->np_thread_lock);
-		if (np->np_thread_state == ISCSI_NP_THREAD_RESET) {
-			spin_unlock_bh(&np->np_thread_lock);
-			complete(&np->np_restart_comp);
-			/* Get another socket */
-			return 1;
-		}
-		spin_unlock_bh(&np->np_thread_lock);
-		goto out;
-	}
-	iscsi_start_login_thread_timer(np);
-
 	conn = kzalloc(sizeof(struct iscsi_conn), GFP_KERNEL);
 	if (!conn) {
 		pr_err("Could not allocate memory for"
 			" new connection\n");
-		sock_release(new_sock);
 		/* Get another socket */
 		return 1;
 	}
-
 	pr_debug("Moving to TARG_CONN_STATE_FREE.\n");
 	conn->conn_state = TARG_CONN_STATE_FREE;
-	conn->sock = new_sock;
 
-	pr_debug("Moving to TARG_CONN_STATE_XPT_UP.\n");
-	conn->conn_state = TARG_CONN_STATE_XPT_UP;
+	if (iscsit_conn_set_transport(conn, np->np_transport) < 0) {
+		kfree(conn);
+		return 1;
+	}
 
-	/*
-	 * Allocate conn->conn_ops early as a failure calling
-	 * iscsit_tx_login_rsp() below will call tx_data().
-	 */
-	conn->conn_ops = kzalloc(sizeof(struct iscsi_conn_ops), GFP_KERNEL);
-	if (!conn->conn_ops) {
-		pr_err("Unable to allocate memory for"
-			" struct iscsi_conn_ops.\n");
-		goto new_sess_out;
+	rc = np->np_transport->iscsit_accept_np(np, conn);
+	if (rc == -ENOSYS) {
+		complete(&np->np_restart_comp);
+		iscsit_put_transport(conn->conn_transport);
+		kfree(conn);
+		conn = NULL;
+		goto exit;
+	} else if (rc < 0) {
+		spin_lock_bh(&np->np_thread_lock);
+		if (np->np_thread_state == ISCSI_NP_THREAD_RESET) {
+			spin_unlock_bh(&np->np_thread_lock);
+			complete(&np->np_restart_comp);
+			if (ret == -ENODEV) {
+				iscsit_put_transport(conn->conn_transport);
+				kfree(conn);
+				conn = NULL;
+				goto out;
+			}
+			/* Get another socket */
+			return 1;
+		}
+		spin_unlock_bh(&np->np_thread_lock);
+		iscsit_put_transport(conn->conn_transport);
+		kfree(conn);
+		conn = NULL;
+		goto out;
 	}
 	/*
 	 * Perform the remaining iSCSI connection initialization items..
 	 */
-	if (iscsi_login_init_conn(conn) < 0)
-		goto new_sess_out;
-
-	memset(buffer, 0, ISCSI_HDR_LEN);
-	memset(&iov, 0, sizeof(struct kvec));
-	iov.iov_base	= buffer;
-	iov.iov_len	= ISCSI_HDR_LEN;
-
-	if (rx_data(conn, &iov, 1, ISCSI_HDR_LEN) <= 0) {
-		pr_err("rx_data() returned an error.\n");
+	login = iscsi_login_init_conn(conn);
+	if (!login) {
 		goto new_sess_out;
 	}
 
-	iscsi_opcode = (buffer[0] & ISCSI_OPCODE_MASK);
-	if (!(iscsi_opcode & ISCSI_OP_LOGIN)) {
-		pr_err("First opcode is not login request,"
-			" failing login request.\n");
-		goto new_sess_out;
-	}
+	iscsi_start_login_thread_timer(np);
 
-	pdu			= (struct iscsi_login_req *) buffer;
+	pr_debug("Moving to TARG_CONN_STATE_XPT_UP.\n");
+	conn->conn_state = TARG_CONN_STATE_XPT_UP;
+	/*
+	 * This will process the first login request + payload..
+	 */
+	rc = np->np_transport->iscsit_get_login_rx(conn, login);
+	if (rc == 1)
+		return 1;
+	else if (rc < 0)
+		goto new_sess_out;
 
+	buffer = &login->req[0];
+	pdu = (struct iscsi_login_req *)buffer;
 	/*
 	 * Used by iscsit_tx_login_rsp() for Login Resonses PDUs
 	 * when Status-Class != 0.
 	*/
-	conn->login_itt		= pdu->itt;
+	conn->login_itt	= pdu->itt;
 
 	spin_lock_bh(&np->np_thread_lock);
 	if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
@@ -967,61 +1167,11 @@ static int __iscsi_target_login_thread(struct iscsi_np *np)
 	}
 	spin_unlock_bh(&np->np_thread_lock);
 
-	if (np->np_sockaddr.ss_family == AF_INET6) {
-		memset(&sock_in6, 0, sizeof(struct sockaddr_in6));
-
-		if (conn->sock->ops->getname(conn->sock,
-				(struct sockaddr *)&sock_in6, &err, 1) < 0) {
-			pr_err("sock_ops->getname() failed.\n");
-			iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
-					ISCSI_LOGIN_STATUS_TARGET_ERROR);
-			goto new_sess_out;
-		}
-		snprintf(conn->login_ip, sizeof(conn->login_ip), "%pI6c",
-				&sock_in6.sin6_addr.in6_u);
-		conn->login_port = ntohs(sock_in6.sin6_port);
-
-		if (conn->sock->ops->getname(conn->sock,
-				(struct sockaddr *)&sock_in6, &err, 0) < 0) {
-			pr_err("sock_ops->getname() failed.\n");
-			iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
-					ISCSI_LOGIN_STATUS_TARGET_ERROR);
-			goto new_sess_out;
-		}
-		snprintf(conn->local_ip, sizeof(conn->local_ip), "%pI6c",
-				&sock_in6.sin6_addr.in6_u);
-		conn->local_port = ntohs(sock_in6.sin6_port);
-
-	} else {
-		memset(&sock_in, 0, sizeof(struct sockaddr_in));
-
-		if (conn->sock->ops->getname(conn->sock,
-				(struct sockaddr *)&sock_in, &err, 1) < 0) {
-			pr_err("sock_ops->getname() failed.\n");
-			iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
-					ISCSI_LOGIN_STATUS_TARGET_ERROR);
-			goto new_sess_out;
-		}
-		sprintf(conn->login_ip, "%pI4", &sock_in.sin_addr.s_addr);
-		conn->login_port = ntohs(sock_in.sin_port);
-
-		if (conn->sock->ops->getname(conn->sock,
-				(struct sockaddr *)&sock_in, &err, 0) < 0) {
-			pr_err("sock_ops->getname() failed.\n");
-			iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
-					ISCSI_LOGIN_STATUS_TARGET_ERROR);
-			goto new_sess_out;
-		}
-		sprintf(conn->local_ip, "%pI4", &sock_in.sin_addr.s_addr);
-		conn->local_port = ntohs(sock_in.sin_port);
-	}
-
 	conn->network_transport = np->np_network_transport;
 
 	pr_debug("Received iSCSI login request from %s on %s Network"
-			" Portal %s:%hu\n", conn->login_ip,
-		(conn->network_transport == ISCSI_TCP) ? "TCP" : "SCTP",
-			conn->local_ip, conn->local_port);
+		" Portal %s:%hu\n", conn->login_ip, np->np_transport->name,
+		conn->local_ip, conn->local_port);
 
 	pr_debug("Moving to TARG_CONN_STATE_IN_LOGIN.\n");
 	conn->conn_state	= TARG_CONN_STATE_IN_LOGIN;
@@ -1050,13 +1200,17 @@ static int __iscsi_target_login_thread(struct iscsi_np *np)
 		if (iscsi_login_non_zero_tsih_s1(conn, buffer) < 0)
 			goto new_sess_out;
 	}
-
 	/*
-	 * This will process the first login request, and call
-	 * iscsi_target_locate_portal(), and return a valid struct iscsi_login.
+	 * SessionType: Discovery
+	 *
+	 * 	Locates Default Portal
+	 *
+	 * SessionType: Normal
+	 *
+	 * 	Locates Target Portal from NP -> Target IQN
 	 */
-	login = iscsi_target_init_negotiation(np, conn, buffer);
-	if (!login) {
+	rc = iscsi_target_locate_portal(np, conn, login);
+	if (rc < 0) {
 		tpg = conn->tpg;
 		goto new_sess_out;
 	}
@@ -1068,15 +1222,11 @@ static int __iscsi_target_login_thread(struct iscsi_np *np)
 	}
 
 	if (zero_tsih) {
-		if (iscsi_login_zero_tsih_s2(conn) < 0) {
-			iscsi_target_nego_release(login, conn);
+		if (iscsi_login_zero_tsih_s2(conn) < 0)
 			goto new_sess_out;
-		}
 	} else {
-		if (iscsi_login_non_zero_tsih_s2(conn, buffer) < 0) {
-			iscsi_target_nego_release(login, conn);
+		if (iscsi_login_non_zero_tsih_s2(conn, buffer) < 0)
 			goto old_sess_out;
-		}
 	}
 
 	if (iscsi_target_start_negotiation(login, conn) < 0)
@@ -1153,8 +1303,18 @@ old_sess_out:
 		iscsi_release_param_list(conn->param_list);
 		conn->param_list = NULL;
 	}
-	if (conn->sock)
+	iscsi_target_nego_release(conn);
+
+	if (conn->sock) {
 		sock_release(conn->sock);
+		conn->sock = NULL;
+	}
+
+	if (conn->conn_transport->iscsit_free_conn)
+		conn->conn_transport->iscsit_free_conn(conn);
+
+	iscsit_put_transport(conn->conn_transport);
+
 	kfree(conn);
 
 	if (tpg) {
@@ -1172,11 +1332,13 @@ out:
 	/* Wait for another socket.. */
 	if (!stop)
 		return 1;
-
+exit:
 	iscsi_stop_login_thread_timer(np);
 	spin_lock_bh(&np->np_thread_lock);
 	np->np_thread_state = ISCSI_NP_THREAD_EXIT;
+	np->np_thread = NULL;
 	spin_unlock_bh(&np->np_thread_lock);
+
 	return 0;
 }