sunrpc: Create a client/ subdirectory in the sunrpc sysfs

/*

 * Copyright (c) 2020 Anna Schumaker <Anna.Schumaker@Netapp.com>

 */

#include <linux/sunrpc/clnt.h>

#include <linux/kobject.h>

static struct kset *rpc_sunrpc_kset;

static struct kobject *rpc_sunrpc_client_kobj;

static void rpc_sysfs_object_release(struct kobject *kobj)

{

	kfree(kobj);

}

static const struct kobj_ns_type_operations *

rpc_sysfs_object_child_ns_type(struct kobject *kobj)

{

	return &net_ns_type_operations;

}

static struct kobj_type rpc_sysfs_object_type = {

	.release = rpc_sysfs_object_release,

	.sysfs_ops = &kobj_sysfs_ops,

	.child_ns_type = rpc_sysfs_object_child_ns_type,

};

static struct kobject *rpc_sysfs_object_alloc(const char *name,

					      struct kset *kset,

					      struct kobject *parent)

{

	struct kobject *kobj;

	kobj = kzalloc(sizeof(*kobj), GFP_KERNEL);

	if (kobj) {

		kobj->kset = kset;

		if (kobject_init_and_add(kobj, &rpc_sysfs_object_type,

					 parent, "%s", name) == 0)

			return kobj;

		kobject_put(kobj);

	}

	return NULL;

}

int rpc_sysfs_init(void)

{

	rpc_sunrpc_kset = kset_create_and_add("sunrpc", NULL, kernel_kobj);

	if (!rpc_sunrpc_kset)

		return -ENOMEM;

	rpc_sunrpc_client_kobj = rpc_sysfs_object_alloc("client", rpc_sunrpc_kset, NULL);

	if (!rpc_sunrpc_client_kobj) {

		kset_unregister(rpc_sunrpc_kset);

		rpc_sunrpc_client_kobj = NULL;

		return -ENOMEM;

	}

	return 0;

}

void rpc_sysfs_exit(void)

{

	kobject_put(rpc_sunrpc_client_kobj);

	kset_unregister(rpc_sunrpc_kset);

}