// SPDX-License-Identifier: GPL-2.0-or-later
/* sysctls for configuring RxRPC operating parameters
 *
 * Copyright (C) 2014 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 */

#include <linux/sysctl.h>
#include <net/sock.h>
#include <net/af_rxrpc.h>
#include "ar-internal.h"

static struct ctl_table_header *rxrpc_sysctl_reg_table;
static const unsigned int rxrpc_rx_mtu_min = 500;
static const unsigned int rxrpc_jumbo_max = RXRPC_MAX_NR_JUMBO;
static const unsigned int four = 4;
static const unsigned int max_backlog = RXRPC_BACKLOG_MAX - 1;
static const unsigned int n_65535 = 65535;
static const unsigned int n_max_acks = 255;
static const unsigned long one_ms = 1;
static const unsigned long max_ms = 1000;
static const unsigned long one_jiffy = 1;
static const unsigned long max_jiffies = MAX_JIFFY_OFFSET;
#ifdef CONFIG_AF_RXRPC_INJECT_RX_DELAY
static const unsigned long max_500 = 500;
#endif

/*
 * RxRPC operating parameters.
 *
 * See Documentation/networking/rxrpc.rst and the variable definitions for more
 * information on the individual parameters.
 */
static struct ctl_table rxrpc_sysctl_table[] = {
        /* Values measured in milliseconds */
        {
                .procname       = "soft_ack_delay",
                .data           = &rxrpc_soft_ack_delay,
                .maxlen         = sizeof(unsigned long),
                .mode           = 0644,
                .proc_handler   = proc_doulongvec_minmax,
                .extra1         = (void *)&one_ms,
                .extra2         = (void *)&max_ms,
        },
        {
                .procname       = "idle_ack_delay",
                .data           = &rxrpc_idle_ack_delay,
                .maxlen         = sizeof(unsigned long),
                .mode           = 0644,
                .proc_handler   = proc_doulongvec_minmax,
                .extra1         = (void *)&one_ms,
                .extra2         = (void *)&max_ms,
        },
        {
                .procname       = "idle_conn_expiry",
                .data           = &rxrpc_conn_idle_client_expiry,
                .maxlen         = sizeof(unsigned long),
                .mode           = 0644,
                .proc_handler   = proc_doulongvec_ms_jiffies_minmax,
                .extra1         = (void *)&one_jiffy,
                .extra2         = (void *)&max_jiffies,
        },
        {
                .procname       = "idle_conn_fast_expiry",
                .data           = &rxrpc_conn_idle_client_fast_expiry,
                .maxlen         = sizeof(unsigned long),
                .mode           = 0644,
                .proc_handler   = proc_doulongvec_ms_jiffies_minmax,
                .extra1         = (void *)&one_jiffy,
                .extra2         = (void *)&max_jiffies,
        },

        /* Values used in milliseconds */
#ifdef CONFIG_AF_RXRPC_INJECT_RX_DELAY
        {
                .procname       = "inject_rx_delay",
                .data           = &rxrpc_inject_rx_delay,
                .maxlen         = sizeof(unsigned long),
                .mode           = 0644,
                .proc_handler   = proc_doulongvec_minmax,
                .extra1         = (void *)SYSCTL_LONG_ZERO,
                .extra2         = (void *)&max_500,
        },
#endif

        /* Non-time values */
        {
                .procname       = "reap_client_conns",
                .data           = &rxrpc_reap_client_connections,
                .maxlen         = sizeof(unsigned int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec_minmax,
                .extra1         = (void *)SYSCTL_ONE,
                .extra2         = (void *)&n_65535,
        },
        {
                .procname       = "max_backlog",
                .data           = &rxrpc_max_backlog,
                .maxlen         = sizeof(unsigned int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec_minmax,
                .extra1         = (void *)&four,
                .extra2         = (void *)&max_backlog,
        },
        {
                .procname       = "rx_window_size",
                .data           = &rxrpc_rx_window_size,
                .maxlen         = sizeof(unsigned int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec_minmax,
                .extra1         = (void *)SYSCTL_ONE,
                .extra2         = (void *)&n_max_acks,
        },
        {
                .procname       = "rx_mtu",
                .data           = &rxrpc_rx_mtu,
                .maxlen         = sizeof(unsigned int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec_minmax,
                .extra1         = (void *)&rxrpc_rx_mtu_min,
                .extra2         = (void *)&n_65535,
        },
        {
                .procname       = "rx_jumbo_max",
                .data           = &rxrpc_rx_jumbo_max,
                .maxlen         = sizeof(unsigned int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec_minmax,
                .extra1         = (void *)SYSCTL_ONE,
                .extra2         = (void *)&rxrpc_jumbo_max,
        },
};

int __init rxrpc_sysctl_init(void)
{
        rxrpc_sysctl_reg_table = register_net_sysctl(&init_net, "net/rxrpc",
                                                     rxrpc_sysctl_table);
        if (!rxrpc_sysctl_reg_table)
                return -ENOMEM;
        return 0;
}

void rxrpc_sysctl_exit(void)
{
        if (rxrpc_sysctl_reg_table)
                unregister_net_sysctl_table(rxrpc_sysctl_reg_table);
}