[SCSI] iscsi class: add iscsi host set param event

The iscsi class uses the set_param event to set session
and connection params. This patch adds a set_host_param
so we can set host level values.
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

drivers/scsi/scsi_transport_iscsi.c

@@ -967,6 +967,30 @@ iscsi_tgt_dscvr(struct iscsi_transport *transport,
 	return err;
 }
 
+static int
+iscsi_set_host_param(struct iscsi_transport *transport,
+		     struct iscsi_uevent *ev)
+{
+	char *data = (char*)ev + sizeof(*ev);
+	struct Scsi_Host *shost;
+	int err;
+
+	if (!transport->set_host_param)
+		return -ENOSYS;
+
+	shost = scsi_host_lookup(ev->u.set_host_param.host_no);
+	if (IS_ERR(shost)) {
+		printk(KERN_ERR "set_host_param could not find host no %u\n",
+		       ev->u.set_host_param.host_no);
+		return -ENODEV;
+	}
+
+	err = transport->set_host_param(shost, ev->u.set_host_param.param,
+					data, ev->u.set_host_param.len);
+	scsi_host_put(shost);
+	return err;
+}
+
 static int
 iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
@@ -1058,8 +1082,11 @@ iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 	case ISCSI_UEVENT_TGT_DSCVR:
 		err = iscsi_tgt_dscvr(transport, ev);
 		break;
+	case ISCSI_UEVENT_SET_HOST_PARAM:
+		err = iscsi_set_host_param(transport, ev);
+		break;
 	default:
-		err = -EINVAL;
+		err = -ENOSYS;
 		break;
 	}
 

include/scsi/iscsi_if.h

@@ -48,6 +48,7 @@ enum iscsi_uevent_e {
 	ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT	= UEVENT_BASE + 14,
 
 	ISCSI_UEVENT_TGT_DSCVR		= UEVENT_BASE + 15,
+	ISCSI_UEVENT_SET_HOST_PARAM	= UEVENT_BASE + 16,
 
 	/* up events */
 	ISCSI_KEVENT_RECV_PDU		= KEVENT_BASE + 1,
@@ -136,6 +137,11 @@ struct iscsi_uevent {
 			 */
 			uint32_t	enable;
 		} tgt_dscvr;
+		struct msg_set_host_param {
+			uint32_t	host_no;
+			uint32_t	param; /* enum iscsi_host_param */
+			uint32_t	len;
+		} set_host_param;
 	} u;
 	union {
 		/* messages k -> u */

include/scsi/scsi_transport_iscsi.h

@@ -108,6 +108,9 @@ struct iscsi_transport {
 				  enum iscsi_param param, char *buf);
 	int (*get_host_param) (struct Scsi_Host *shost,
 				enum iscsi_host_param param, char *buf);
+	int (*set_host_param) (struct Scsi_Host *shost,
+			       enum iscsi_host_param param, char *buf,
+			       int buflen);
 	int (*send_pdu) (struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
 			 char *data, uint32_t data_size);
 	void (*get_stats) (struct iscsi_cls_conn *conn,