hv: move "device_id" bus attribute to dev_groups

This moves the "device_id" bus attribute to the dev_groups structure,
removing the need for it to be in a temporary structure.
Tested-by: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/hv/channel.c

@@ -69,10 +69,6 @@ void vmbus_get_debug_info(struct vmbus_channel *channel,
 	u8 monitor_group = (u8)channel->offermsg.monitorid / 32;
 	u8 monitor_offset = (u8)channel->offermsg.monitorid % 32;
 
-	memcpy(&debuginfo->interface_instance,
-	       &channel->offermsg.offer.if_instance,
-	       sizeof(uuid_le));
-
 	monitorpage = (struct hv_monitor_page *)vmbus_connection.monitor_pages;
 
 	debuginfo->servermonitor_pending =

drivers/hv/vmbus_drv.c

@@ -47,8 +47,6 @@ static struct completion probe_event;
 static int irq;
 
 struct hv_device_info {
-	uuid_le chn_instance;
-
 	u32 server_monitor_pending;
 	u32 server_monitor_latency;
 	u32 server_monitor_conn_id;
@@ -79,9 +77,6 @@ static void get_channel_info(struct hv_device *device,
 
 	vmbus_get_debug_info(device->channel, &debug_info);
 
-	memcpy(&info->chn_instance, &debug_info.interface_instance,
-	       sizeof(uuid_le));
-
 	info->server_monitor_pending = debug_info.servermonitor_pending;
 	info->server_monitor_latency = debug_info.servermonitor_latency;
 	info->server_monitor_conn_id = debug_info.servermonitor_connectionid;
@@ -136,9 +131,7 @@ static ssize_t vmbus_show_device_attr(struct device *dev,
 
 	get_channel_info(hv_dev, device_info);
 
-	if (!strcmp(dev_attr->attr.name, "device_id")) {
-		ret = sprintf(buf, "{%pUl}\n", device_info->chn_instance.b);
-	} else if (!strcmp(dev_attr->attr.name, "out_intr_mask")) {
+	if (!strcmp(dev_attr->attr.name, "out_intr_mask")) {
 		ret = sprintf(buf, "%d\n", device_info->outbound.int_mask);
 	} else if (!strcmp(dev_attr->attr.name, "out_read_index")) {
 		ret = sprintf(buf, "%d\n", device_info->outbound.read_idx);
@@ -227,6 +220,18 @@ static ssize_t class_id_show(struct device *dev,
 }
 static DEVICE_ATTR_RO(class_id);
 
+static ssize_t device_id_show(struct device *dev,
+			      struct device_attribute *dev_attr, char *buf)
+{
+	struct hv_device *hv_dev = device_to_hv_device(dev);
+
+	if (!hv_dev->channel)
+		return -ENODEV;
+	return sprintf(buf, "{%pUl}\n",
+		       hv_dev->channel->offermsg.offer.if_instance.b);
+}
+static DEVICE_ATTR_RO(device_id);
+
 static ssize_t modalias_show(struct device *dev,
 			     struct device_attribute *dev_attr, char *buf)
 {
@@ -244,6 +249,7 @@ static struct attribute *vmbus_attrs[] = {
 	&dev_attr_state.attr,
 	&dev_attr_monitor_id.attr,
 	&dev_attr_class_id.attr,
+	&dev_attr_device_id.attr,
 	&dev_attr_modalias.attr,
 	NULL,
 };
@@ -251,8 +257,6 @@ ATTRIBUTE_GROUPS(vmbus);
 
 /* Set up per device attributes in /sys/bus/vmbus/devices/<bus device> */
 static struct device_attribute vmbus_device_attrs[] = {
-	__ATTR(device_id, S_IRUGO, vmbus_show_device_attr, NULL),
-
 	__ATTR(server_monitor_pending, S_IRUGO, vmbus_show_device_attr, NULL),
 	__ATTR(server_monitor_latency, S_IRUGO, vmbus_show_device_attr, NULL),
 	__ATTR(server_monitor_conn_id, S_IRUGO, vmbus_show_device_attr, NULL),

include/linux/hyperv.h

@@ -900,7 +900,6 @@ enum vmbus_channel_state {
 };
 
 struct vmbus_channel_debug_info {
-	uuid_le interface_instance;
 	u32 servermonitor_pending;
 	u32 servermonitor_latency;
 	u32 servermonitor_connectionid;