// SPDX-License-Identifier: GPL-2.0
  /*
   * linux/fs/nfs/nfs4sysctl.c
   *
   * Sysctl interface to NFS v4 parameters
   *
   * Copyright (c) 2006 Trond Myklebust <Trond.Myklebust@netapp.com>
   */
  #include <linux/sysctl.h>
  #include <linux/nfs_fs.h>
  
  #include "nfs4_fs.h"
  #include "nfs4idmap.h"
  #include "callback.h"
  
  static const int nfs_set_port_min;
  static const int nfs_set_port_max = 65535;
  static struct ctl_table_header *nfs4_callback_sysctl_table;
  
  static struct ctl_table nfs4_cb_sysctls[] = {
  	{
  		.procname = "nfs_callback_tcpport",
  		.data = &nfs_callback_set_tcpport,
  		.maxlen = sizeof(int),
  		.mode = 0644,
  		.proc_handler = proc_dointvec_minmax,
  		.extra1 = (int *)&nfs_set_port_min,
  		.extra2 = (int *)&nfs_set_port_max,
  	},
  	{
  		.procname = "idmap_cache_timeout",
  		.data = &nfs_idmap_cache_timeout,
  		.maxlen = sizeof(int),
  		.mode = 0644,
  		.proc_handler = proc_dointvec,
  	},
  	{ }
  };
  
  static struct ctl_table nfs4_cb_sysctl_dir[] = {
  	{
  		.procname = "nfs",
  		.mode = 0555,
  		.child = nfs4_cb_sysctls,
  	},
  	{ }
  };
  
  static struct ctl_table nfs4_cb_sysctl_root[] = {
  	{
  		.procname = "fs",
  		.mode = 0555,
  		.child = nfs4_cb_sysctl_dir,
  	},
  	{ }
  };
  
  int nfs4_register_sysctl(void)
  {
  	nfs4_callback_sysctl_table = register_sysctl_table(nfs4_cb_sysctl_root);
  	if (nfs4_callback_sysctl_table == NULL)
  		return -ENOMEM;
  	return 0;
  }
  
  void nfs4_unregister_sysctl(void)
  {
  	unregister_sysctl_table(nfs4_callback_sysctl_table);
  	nfs4_callback_sysctl_table = NULL;
  }