RDMA/core: Depend on device_add() to add device attributes

Instead of adding/removing device attribute files, depend on device_add()
which considers adding these device files based on NULL terminated
attributes group array.
Signed-off-by: NParav Pandit <parav@mellanox.com>
Reviewed-by: NDaniel Jurgens <danielj@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/core/sysfs.c

@@ -1183,7 +1183,7 @@ static int add_port(struct ib_device *device, int port_num,
 	return ret;
 }
 
-static ssize_t show_node_type(struct device *device,
+static ssize_t node_type_show(struct device *device,
 			      struct device_attribute *attr, char *buf)
 {
 	struct ib_device *dev = container_of(device, struct ib_device, dev);
@@ -1198,8 +1198,9 @@ static ssize_t show_node_type(struct device *device,
 	default:		  return sprintf(buf, "%d: <unknown>\n", dev->node_type);
 	}
 }
+static DEVICE_ATTR_RO(node_type);
 
-static ssize_t show_sys_image_guid(struct device *device,
+static ssize_t sys_image_guid_show(struct device *device,
 				   struct device_attribute *dev_attr, char *buf)
 {
 	struct ib_device *dev = container_of(device, struct ib_device, dev);
@@ -1210,8 +1211,9 @@ static ssize_t show_sys_image_guid(struct device *device,
 		       be16_to_cpu(((__be16 *) &dev->attrs.sys_image_guid)[2]),
 		       be16_to_cpu(((__be16 *) &dev->attrs.sys_image_guid)[3]));
 }
+static DEVICE_ATTR_RO(sys_image_guid);
 
-static ssize_t show_node_guid(struct device *device,
+static ssize_t node_guid_show(struct device *device,
 			      struct device_attribute *attr, char *buf)
 {
 	struct ib_device *dev = container_of(device, struct ib_device, dev);
@@ -1222,8 +1224,9 @@ static ssize_t show_node_guid(struct device *device,
 		       be16_to_cpu(((__be16 *) &dev->node_guid)[2]),
 		       be16_to_cpu(((__be16 *) &dev->node_guid)[3]));
 }
+static DEVICE_ATTR_RO(node_guid);
 
-static ssize_t show_node_desc(struct device *device,
+static ssize_t node_desc_show(struct device *device,
 			      struct device_attribute *attr, char *buf)
 {
 	struct ib_device *dev = container_of(device, struct ib_device, dev);
@@ -1231,9 +1234,9 @@ static ssize_t show_node_desc(struct device *device,
 	return sprintf(buf, "%.64s\n", dev->node_desc);
 }
 
-static ssize_t set_node_desc(struct device *device,
-			     struct device_attribute *attr,
-			     const char *buf, size_t count)
+static ssize_t node_desc_store(struct device *device,
+			       struct device_attribute *attr,
+			       const char *buf, size_t count)
 {
 	struct ib_device *dev = container_of(device, struct ib_device, dev);
 	struct ib_device_modify desc = {};
@@ -1249,8 +1252,9 @@ static ssize_t set_node_desc(struct device *device,
 
 	return count;
 }
+static DEVICE_ATTR_RW(node_desc);
 
-static ssize_t show_fw_ver(struct device *device, struct device_attribute *attr,
+static ssize_t fw_ver_show(struct device *device, struct device_attribute *attr,
 			   char *buf)
 {
 	struct ib_device *dev = container_of(device, struct ib_device, dev);
@@ -1259,19 +1263,19 @@ static ssize_t show_fw_ver(struct device *device, struct device_attribute *attr,
 	strlcat(buf, "\n", IB_FW_VERSION_NAME_MAX);
 	return strlen(buf);
 }
+static DEVICE_ATTR_RO(fw_ver);
+
+static struct attribute *ib_dev_attrs[] = {
+	&dev_attr_node_type.attr,
+	&dev_attr_node_guid.attr,
+	&dev_attr_sys_image_guid.attr,
+	&dev_attr_fw_ver.attr,
+	&dev_attr_node_desc.attr,
+	NULL,
+};
 
-static DEVICE_ATTR(node_type, S_IRUGO, show_node_type, NULL);
-static DEVICE_ATTR(sys_image_guid, S_IRUGO, show_sys_image_guid, NULL);
-static DEVICE_ATTR(node_guid, S_IRUGO, show_node_guid, NULL);
-static DEVICE_ATTR(node_desc, S_IRUGO | S_IWUSR, show_node_desc, set_node_desc);
-static DEVICE_ATTR(fw_ver, S_IRUGO, show_fw_ver, NULL);
-
-static struct device_attribute *ib_class_attributes[] = {
-	&dev_attr_node_type,
-	&dev_attr_sys_image_guid,
-	&dev_attr_node_guid,
-	&dev_attr_node_desc,
-	&dev_attr_fw_ver,
+static const struct attribute_group dev_attr_group = {
+	.attrs = ib_dev_attrs,
 };
 
 static void free_port_list_attributes(struct ib_device *device)
@@ -1311,16 +1315,13 @@ int ib_device_register_sysfs(struct ib_device *device,
 	if (ret)
 		return ret;
 
+	device->groups[0] = &dev_attr_group;
+	class_dev->groups = device->groups;
+
 	ret = device_add(class_dev);
 	if (ret)
 		goto err;
 
-	for (i = 0; i < ARRAY_SIZE(ib_class_attributes); ++i) {
-		ret = device_create_file(class_dev, ib_class_attributes[i]);
-		if (ret)
-			goto err_unregister;
-	}
-
 	device->ports_parent = kobject_create_and_add("ports",
 						      &class_dev->kobj);
 	if (!device->ports_parent) {
@@ -1347,18 +1348,13 @@ int ib_device_register_sysfs(struct ib_device *device,
 
 err_put:
 	free_port_list_attributes(device);
-
-err_unregister:
 	device_del(class_dev);
-
 err:
 	return ret;
 }
 
 void ib_device_unregister_sysfs(struct ib_device *device)
 {
-	int i;
-
 	/* Hold kobject until ib_dealloc_device() */
 	kobject_get(&device->dev.kobj);
 
@@ -1369,8 +1365,5 @@ void ib_device_unregister_sysfs(struct ib_device *device)
 		free_hsag(&device->dev.kobj, device->hw_stats_ag);
 	}
 
-	for (i = 0; i < ARRAY_SIZE(ib_class_attributes); ++i)
-		device_remove_file(&device->dev, ib_class_attributes[i]);
-
 	device_unregister(&device->dev);
 }

include/rdma/ib_verbs.h

@@ -2536,6 +2536,9 @@ struct ib_device {
 
 	struct module               *owner;
 	struct device                dev;
+	/* First group for device attributes, NULL terminated array */
+	const struct attribute_group	*groups[2];
+
 	struct kobject               *ports_parent;
 	struct list_head             port_list;