/*
   * Copyright (c) 2006 Oracle.  All rights reserved.
   *
   * This software is available to you under a choice of one of two
   * licenses.  You may choose to be licensed under the terms of the GNU
   * General Public License (GPL) Version 2, available from the file
   * COPYING in the main directory of this source tree, or the
   * OpenIB.org BSD license below:
   *
   *     Redistribution and use in source and binary forms, with or
   *     without modification, are permitted provided that the following
   *     conditions are met:
   *
   *      - Redistributions of source code must retain the above
   *        copyright notice, this list of conditions and the following
   *        disclaimer.
   *
   *      - Redistributions in binary form must reproduce the above
   *        copyright notice, this list of conditions and the following
   *        disclaimer in the documentation and/or other materials
   *        provided with the distribution.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
   * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
   * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
   * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
   * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
   * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
   * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
   * SOFTWARE.
   *
   */
  #include <linux/kernel.h>
  #include <linux/sysctl.h>
  #include <linux/proc_fs.h>
  
  #include "ib.h"
  
  static struct ctl_table_header *rds_ib_sysctl_hdr;
  
  unsigned long rds_ib_sysctl_max_send_wr = RDS_IB_DEFAULT_SEND_WR;
  unsigned long rds_ib_sysctl_max_recv_wr = RDS_IB_DEFAULT_RECV_WR;
  unsigned long rds_ib_sysctl_max_recv_allocation = (128 * 1024 * 1024) / RDS_FRAG_SIZE;
  static unsigned long rds_ib_sysctl_max_wr_min = 1;
  /* hardware will fail CQ creation long before this */
  static unsigned long rds_ib_sysctl_max_wr_max = (u32)~0;
  
  unsigned long rds_ib_sysctl_max_unsig_wrs = 16;
  static unsigned long rds_ib_sysctl_max_unsig_wr_min = 1;
  static unsigned long rds_ib_sysctl_max_unsig_wr_max = 64;
  
  /*
   * This sysctl does nothing.
   *
   * Backwards compatibility with RDS 3.0 wire protocol
   * disables initial FC credit exchange.
   * If it's ever possible to drop 3.0 support,
   * setting this to 1 and moving init/refill of send/recv
   * rings from ib_cm_connect_complete() back into ib_setup_qp()
   * will cause credits to be added before protocol negotiation.
   */
  unsigned int rds_ib_sysctl_flow_control = 0;
  
  static struct ctl_table rds_ib_sysctl_table[] = {
  	{
  		.procname       = "max_send_wr",
  		.data		= &rds_ib_sysctl_max_send_wr,
  		.maxlen         = sizeof(unsigned long),
  		.mode           = 0644,
  		.proc_handler   = proc_doulongvec_minmax,
  		.extra1		= &rds_ib_sysctl_max_wr_min,
  		.extra2		= &rds_ib_sysctl_max_wr_max,
  	},
  	{
  		.procname       = "max_recv_wr",
  		.data		= &rds_ib_sysctl_max_recv_wr,
  		.maxlen         = sizeof(unsigned long),
  		.mode           = 0644,
  		.proc_handler   = proc_doulongvec_minmax,
  		.extra1		= &rds_ib_sysctl_max_wr_min,
  		.extra2		= &rds_ib_sysctl_max_wr_max,
  	},
  	{
  		.procname       = "max_unsignaled_wr",
  		.data		= &rds_ib_sysctl_max_unsig_wrs,
  		.maxlen         = sizeof(unsigned long),
  		.mode           = 0644,
  		.proc_handler   = proc_doulongvec_minmax,
  		.extra1		= &rds_ib_sysctl_max_unsig_wr_min,
  		.extra2		= &rds_ib_sysctl_max_unsig_wr_max,
  	},
  	{
  		.procname       = "max_recv_allocation",
  		.data		= &rds_ib_sysctl_max_recv_allocation,
  		.maxlen         = sizeof(unsigned long),
  		.mode           = 0644,
  		.proc_handler   = proc_doulongvec_minmax,
  	},
  	{
  		.procname	= "flow_control",
  		.data		= &rds_ib_sysctl_flow_control,
  		.maxlen		= sizeof(rds_ib_sysctl_flow_control),
  		.mode		= 0644,
  		.proc_handler	= proc_dointvec,
  	},
  	{ }
  };
  
  void rds_ib_sysctl_exit(void)
  {
  	if (rds_ib_sysctl_hdr)
  		unregister_net_sysctl_table(rds_ib_sysctl_hdr);
  }
  
  int rds_ib_sysctl_init(void)
  {
  	rds_ib_sysctl_hdr = register_net_sysctl(&init_net, "net/rds/ib", rds_ib_sysctl_table);
  	if (!rds_ib_sysctl_hdr)
  		return -ENOMEM;
  	return 0;
  }