IB/srp: Add SCSI host attributes to show target port

Add SCSI host attributes in sysfs that show the ID extension, IOC
GUID, service ID, P_Key and destination GID for each target port that
the SRP initiator connects to.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c
index 960dae5..89ad29d 100644
--- a/drivers/infiniband/ulp/srp/ib_srp.c
+++ b/drivers/infiniband/ulp/srp/ib_srp.c
@@ -1237,6 +1237,87 @@
 	return ret;
 }
 
+static ssize_t show_id_ext(struct class_device *cdev, char *buf)
+{
+	struct srp_target_port *target = host_to_target(class_to_shost(cdev));
+
+	if (target->state == SRP_TARGET_DEAD ||
+	    target->state == SRP_TARGET_REMOVED)
+		return -ENODEV;
+
+	return sprintf(buf, "0x%016llx\n",
+		       (unsigned long long) be64_to_cpu(target->id_ext));
+}
+
+static ssize_t show_ioc_guid(struct class_device *cdev, char *buf)
+{
+	struct srp_target_port *target = host_to_target(class_to_shost(cdev));
+
+	if (target->state == SRP_TARGET_DEAD ||
+	    target->state == SRP_TARGET_REMOVED)
+		return -ENODEV;
+
+	return sprintf(buf, "0x%016llx\n",
+		       (unsigned long long) be64_to_cpu(target->ioc_guid));
+}
+
+static ssize_t show_service_id(struct class_device *cdev, char *buf)
+{
+	struct srp_target_port *target = host_to_target(class_to_shost(cdev));
+
+	if (target->state == SRP_TARGET_DEAD ||
+	    target->state == SRP_TARGET_REMOVED)
+		return -ENODEV;
+
+	return sprintf(buf, "0x%016llx\n",
+		       (unsigned long long) be64_to_cpu(target->service_id));
+}
+
+static ssize_t show_pkey(struct class_device *cdev, char *buf)
+{
+	struct srp_target_port *target = host_to_target(class_to_shost(cdev));
+
+	if (target->state == SRP_TARGET_DEAD ||
+	    target->state == SRP_TARGET_REMOVED)
+		return -ENODEV;
+
+	return sprintf(buf, "0x%04x\n", be16_to_cpu(target->path.pkey));
+}
+
+static ssize_t show_dgid(struct class_device *cdev, char *buf)
+{
+	struct srp_target_port *target = host_to_target(class_to_shost(cdev));
+
+	if (target->state == SRP_TARGET_DEAD ||
+	    target->state == SRP_TARGET_REMOVED)
+		return -ENODEV;
+
+	return sprintf(buf, "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
+		       be16_to_cpu(((__be16 *) target->path.dgid.raw)[0]),
+		       be16_to_cpu(((__be16 *) target->path.dgid.raw)[1]),
+		       be16_to_cpu(((__be16 *) target->path.dgid.raw)[2]),
+		       be16_to_cpu(((__be16 *) target->path.dgid.raw)[3]),
+		       be16_to_cpu(((__be16 *) target->path.dgid.raw)[4]),
+		       be16_to_cpu(((__be16 *) target->path.dgid.raw)[5]),
+		       be16_to_cpu(((__be16 *) target->path.dgid.raw)[6]),
+		       be16_to_cpu(((__be16 *) target->path.dgid.raw)[7]));
+}
+
+static CLASS_DEVICE_ATTR(id_ext,	S_IRUGO, show_id_ext,		NULL);
+static CLASS_DEVICE_ATTR(ioc_guid,	S_IRUGO, show_ioc_guid,		NULL);
+static CLASS_DEVICE_ATTR(service_id,	S_IRUGO, show_service_id,	NULL);
+static CLASS_DEVICE_ATTR(pkey,		S_IRUGO, show_pkey,		NULL);
+static CLASS_DEVICE_ATTR(dgid,		S_IRUGO, show_dgid,		NULL);
+
+static struct class_device_attribute *srp_host_attrs[] = {
+	&class_device_attr_id_ext,
+	&class_device_attr_ioc_guid,
+	&class_device_attr_service_id,
+	&class_device_attr_pkey,
+	&class_device_attr_dgid,
+	NULL
+};
+
 static struct scsi_host_template srp_template = {
 	.module				= THIS_MODULE,
 	.name				= DRV_NAME,
@@ -1249,7 +1330,8 @@
 	.this_id			= -1,
 	.sg_tablesize			= SRP_MAX_INDIRECT,
 	.cmd_per_lun			= SRP_SQ_SIZE,
-	.use_clustering			= ENABLE_CLUSTERING
+	.use_clustering			= ENABLE_CLUSTERING,
+	.shost_attrs			= srp_host_attrs
 };
 
 static int srp_add_target(struct srp_host *host, struct srp_target_port *target)