[SCSI] libiscsi: Added new boot entries in the session sysfs

This is the kernel part of the modification to extract the net params
from the ibft sysfs to the iface struct used for the connection
request upon sync_session in the open-iscsi util.

Three new session sysfs params are defined:
boot_root - holds the name of the /sys/firmware/ibft or iscsi_rootN
boot_nic  - holds the ethernetN name
boot_target - holds the targetN name

Signed-off-by: Eddie Wai <eddie.wai@broadcom.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

drivers/scsi/libiscsi.c

@@ -2808,6 +2808,9 @@ void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
 	kfree(session->targetname);
 	kfree(session->targetalias);
 	kfree(session->initiatorname);
+	kfree(session->boot_root);
+	kfree(session->boot_nic);
+	kfree(session->boot_target);
 	kfree(session->ifacename);
 
 	iscsi_destroy_session(cls_session);
@@ -3248,6 +3251,12 @@ int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
 		return iscsi_switch_str_param(&session->ifacename, buf);
 	case ISCSI_PARAM_INITIATOR_NAME:
 		return iscsi_switch_str_param(&session->initiatorname, buf);
+	case ISCSI_PARAM_BOOT_ROOT:
+		return iscsi_switch_str_param(&session->boot_root, buf);
+	case ISCSI_PARAM_BOOT_NIC:
+		return iscsi_switch_str_param(&session->boot_nic, buf);
+	case ISCSI_PARAM_BOOT_TARGET:
+		return iscsi_switch_str_param(&session->boot_target, buf);
 	default:
 		return -ENOSYS;
 	}
@@ -3326,6 +3335,15 @@ int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
 	case ISCSI_PARAM_INITIATOR_NAME:
 		len = sprintf(buf, "%s\n", session->initiatorname);
 		break;
+	case ISCSI_PARAM_BOOT_ROOT:
+		len = sprintf(buf, "%s\n", session->boot_root);
+		break;
+	case ISCSI_PARAM_BOOT_NIC:
+		len = sprintf(buf, "%s\n", session->boot_nic);
+		break;
+	case ISCSI_PARAM_BOOT_TARGET:
+		len = sprintf(buf, "%s\n", session->boot_target);
+		break;
 	default:
 		return -ENOSYS;
 	}

drivers/scsi/scsi_transport_iscsi.c

@@ -3473,6 +3473,9 @@ iscsi_session_attr(tgt_reset_tmo, ISCSI_PARAM_TGT_RESET_TMO, 0);
 iscsi_session_attr(ifacename, ISCSI_PARAM_IFACE_NAME, 0);
 iscsi_session_attr(initiatorname, ISCSI_PARAM_INITIATOR_NAME, 0);
 iscsi_session_attr(targetalias, ISCSI_PARAM_TARGET_ALIAS, 0);
+iscsi_session_attr(boot_root, ISCSI_PARAM_BOOT_ROOT, 0);
+iscsi_session_attr(boot_nic, ISCSI_PARAM_BOOT_NIC, 0);
+iscsi_session_attr(boot_target, ISCSI_PARAM_BOOT_TARGET, 0);
 
 static ssize_t
 show_priv_session_state(struct device *dev, struct device_attribute *attr,
@@ -3568,6 +3571,9 @@ static struct attribute *iscsi_session_attrs[] = {
 	&dev_attr_sess_ifacename.attr,
 	&dev_attr_sess_initiatorname.attr,
 	&dev_attr_sess_targetalias.attr,
+	&dev_attr_sess_boot_root.attr,
+	&dev_attr_sess_boot_nic.attr,
+	&dev_attr_sess_boot_target.attr,
 	&dev_attr_priv_sess_recovery_tmo.attr,
 	&dev_attr_priv_sess_state.attr,
 	&dev_attr_priv_sess_creator.attr,
@@ -3631,6 +3637,12 @@ static umode_t iscsi_session_attr_is_visible(struct kobject *kobj,
 		param = ISCSI_PARAM_INITIATOR_NAME;
 	else if (attr == &dev_attr_sess_targetalias.attr)
 		param = ISCSI_PARAM_TARGET_ALIAS;
+	else if (attr == &dev_attr_sess_boot_root.attr)
+		param = ISCSI_PARAM_BOOT_ROOT;
+	else if (attr == &dev_attr_sess_boot_nic.attr)
+		param = ISCSI_PARAM_BOOT_NIC;
+	else if (attr == &dev_attr_sess_boot_target.attr)
+		param = ISCSI_PARAM_BOOT_TARGET;
 	else if (attr == &dev_attr_priv_sess_recovery_tmo.attr)
 		return S_IRUGO | S_IWUSR;
 	else if (attr == &dev_attr_priv_sess_state.attr)

include/scsi/iscsi_if.h

@@ -489,6 +489,11 @@ enum iscsi_param {
 
 	ISCSI_PARAM_CHAP_IN_IDX,
 	ISCSI_PARAM_CHAP_OUT_IDX,
+
+	ISCSI_PARAM_BOOT_ROOT,
+	ISCSI_PARAM_BOOT_NIC,
+	ISCSI_PARAM_BOOT_TARGET,
+
 	/* must always be last */
 	ISCSI_PARAM_MAX,
 };

include/scsi/libiscsi.h

@@ -287,6 +287,10 @@ struct iscsi_session {
 	char			*targetalias;
 	char			*ifacename;
 	char			*initiatorname;
+	char			*boot_root;
+	char			*boot_nic;
+	char			*boot_target;
+
 	/* control data */
 	struct iscsi_transport	*tt;
 	struct Scsi_Host	*host;