/*
* File: sysctl.c
*
* Phonet /proc/sys/net/phonet interface implementation
*
* Copyright (C) 2008 Nokia Corporation.
*
* Contact: Remi Denis-Courmont <remi.denis-courmont@nokia.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*/
#include <linux/seqlock.h>
#include <linux/sysctl.h>
#include <linux/errno.h>
#include <linux/init.h>
#define DYNAMIC_PORT_MIN 0x40
#define DYNAMIC_PORT_MAX 0x7f
static DEFINE_SEQLOCK(local_port_range_lock);
static int local_port_range_min[2] = {0, 0};
static int local_port_range_max[2] = {1023, 1023};
static int local_port_range[2] = {DYNAMIC_PORT_MIN, DYNAMIC_PORT_MAX};
static struct ctl_table_header *phonet_table_hrd;
static void set_local_port_range(int range[2])
{
write_seqlock(&local_port_range_lock);
local_port_range[0] = range[0];
local_port_range[1] = range[1];
write_sequnlock(&local_port_range_lock);
}
void phonet_get_local_port_range(int *min, int *max)
{
unsigned seq;
do {
seq = read_seqbegin(&local_port_range_lock);
if (min)
*min = local_port_range[0];
if (max)
*max = local_port_range[1];
} while (read_seqretry(&local_port_range_lock, seq));
}
static int proc_local_port_range(ctl_table *table, int write,
void __user *buffer,
size_t *lenp, loff_t *ppos)
{
int ret;
int range[2] = {local_port_range[0], local_port_range[1]};
ctl_table tmp = {
.data = &range,
.maxlen = sizeof(range),
.mode = table->mode,
.extra1 = &local_port_range_min,
.extra2 = &local_port_range_max,
};
ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
if (write && ret == 0) {
if (range[1] < range[0])
ret = -EINVAL;
else
set_local_port_range(range);
}
return ret;
}
static struct ctl_table phonet_table[] = {
{
.ctl_name = CTL_UNNUMBERED,
.procname = "local_port_range",
.data = &local_port_range,
.maxlen = sizeof(local_port_range),
.mode = 0644,
.proc_handler = proc_local_port_range,
.strategy = NULL,
},
{ .ctl_name = 0 }
};
static struct ctl_path phonet_ctl_path[] = {
{ .procname = "net", .ctl_name = CTL_NET, },
{ .procname = "phonet", .ctl_name = CTL_UNNUMBERED, },
{ },
};
int __init phonet_sysctl_init(void)
{
phonet_table_hrd = register_sysctl_paths(phonet_ctl_path, phonet_table);
return phonet_table_hrd == NULL ? -ENOMEM : 0;
}
void phonet_sysctl_exit(void)
{
unregister_sysctl_table(phonet_table_hrd);
}
