bind offloaded connection to port

If we are using a offload card, then iface_set_param will match the
iface info to a scsi_host and pass that info down to setup the net
settings of the port (currently we just set the ip address). When we
create the tcp/ip connection by calling ep_connect, we currently just go
by the routing table info.

I think there are two problems with this.

1. Some drivers do not have access to a routing table. Some drivers like
qla4xxx do not even know about other ports.

2. If you have two initiator ports on the same subnet, the user may have
set things up so that session1 was supposed to be run through port1. and
session2 was supposed to be run through port2. It looks like we could
end with both sessions going through one of the ports.

Also how do you edit the routing table for the offload cards? You cannot
use normal net tools like route can you?

3. If we set up hostA in the iface_set_param step, but then the routing
info leads us to hostB, we are stuck.

I did the attached patches to fix this. Basically we just pass down the
scsi host we want to go through.

4 files changed, 17 insertions, 3 deletions

diff --git a/include/iscsi_if.h b/include/iscsi_if.h
index 81f92e8..0fb733d 100644
--- a/include/iscsi_if.h
+++ b/include/iscsi_if.h
@@ -52,6 +52,8 @@ enum iscsi_uevent_e {
 	ISCSI_UEVENT_UNBIND_SESSION	= UEVENT_BASE + 17,
 	ISCSI_UEVENT_CREATE_BOUND_SESSION	= UEVENT_BASE + 18,
 
+	ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST	= UEVENT_BASE + 22,
+
 	/* up events */
 	ISCSI_KEVENT_RECV_PDU		= KEVENT_BASE + 1,
 	ISCSI_KEVENT_CONN_ERROR		= KEVENT_BASE + 2,
@@ -131,6 +133,10 @@ struct iscsi_uevent {
 		struct msg_transport_connect {
 			uint32_t	non_blocking;
 		} ep_connect;
+		struct msg_transport_connect_through_host {
+			uint32_t	host_no;
+			uint32_t	non_blocking;
+		} ep_connect_through_host;
 		struct msg_transport_poll {
 			uint64_t	ep_handle;
 			uint32_t	timeout_ms;
diff --git a/usr/initiator.c b/usr/initiator.c
index 8e4ea6b..4a56347 100644
--- a/usr/initiator.c
+++ b/usr/initiator.c
@@ -2074,7 +2074,7 @@ static int iface_set_param(struct iscsi_transport *t, struct iface_rec *iface,
 	hostno = iscsi_sysfs_get_host_no_from_hwinfo(iface, &rc);
 	if (rc)
 		return rc;
-
+	session->conn[0].bind_ep = 1;
 	session->hostno = hostno;
 
 	rc = __iscsi_host_set_param(t, session->hostno,
diff --git a/usr/initiator.h b/usr/initiator.h
index 682ebfc..5bcf4d1 100644
--- a/usr/initiator.h
+++ b/usr/initiator.h
@@ -152,6 +152,7 @@ typedef struct iscsi_conn {
          * transports (eg iser) which does these ops from the kernel.
          * In the case of TCP, it is just the transport_fd casted to u64. */
 	uint64_t transport_ep_handle;
+	int bind_ep;
 
 	/* timeouts */
 	int login_timeout;
diff --git a/usr/netlink.c b/usr/netlink.c
index 9172259..3d697ef 100644
--- a/usr/netlink.c
+++ b/usr/netlink.c
@@ -757,9 +757,17 @@ ktransport_ep_connect(iscsi_conn_t *conn, int non_blocking)
 
 	memset(setparam_buf, 0, NLM_SETPARAM_DEFAULT_MAX);
 	ev = (struct iscsi_uevent *)setparam_buf;
-	ev->type = ISCSI_UEVENT_TRANSPORT_EP_CONNECT;
 	ev->transport_handle = conn->session->t->handle;
 
+	if (conn->bind_ep) {
+		ev->type = ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST;
+		ev->u.ep_connect_through_host.non_blocking = non_blocking;
+		ev->u.ep_connect_through_host.host_no = conn->session->hostno;
+	} else {
+		ev->type = ISCSI_UEVENT_TRANSPORT_EP_CONNECT;
+		ev->u.ep_connect.non_blocking = non_blocking;
+	}
+
 	if (dst_addr->sa_family == PF_INET)
 		addrlen = sizeof(struct sockaddr_in);
 	else if (dst_addr->sa_family == PF_INET6)
@@ -770,7 +778,6 @@ ktransport_ep_connect(iscsi_conn_t *conn, int non_blocking)
 		return -EINVAL;
 	}
 	memcpy(setparam_buf + sizeof(*ev), dst_addr, addrlen);
-	ev->u.ep_connect.non_blocking = non_blocking;
 
 	if ((rc = __kipc_call(ev, sizeof(*ev) + addrlen)) < 0)
 		return rc;