[deliverable/linux.git] / net / phonet / sysctl.c

/*
 * 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);
}
Commit	Line	Data
87ab4e20 RDC	1	/*
	2	* File: sysctl.c
	3	*
	4	* Phonet /proc/sys/net/phonet interface implementation
	5	*
	6	* Copyright (C) 2008 Nokia Corporation.
	7	*
	8	* Contact: Remi Denis-Courmont <remi.denis-courmont@nokia.com>
	9	*
	10	* This program is free software; you can redistribute it and/or
	11	* modify it under the terms of the GNU General Public License
	12	* version 2 as published by the Free Software Foundation.
	13	*
	14	* This program is distributed in the hope that it will be useful, but
	15	* WITHOUT ANY WARRANTY; without even the implied warranty of
	16	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	17	* General Public License for more details.
	18	*
	19	* You should have received a copy of the GNU General Public License
	20	* along with this program; if not, write to the Free Software
	21	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
	22	* 02110-1301 USA
	23	*/
	24
	25	#include <linux/seqlock.h>
	26	#include <linux/sysctl.h>
	27	#include <linux/errno.h>
	28	#include <linux/init.h>
	29
	30	#define DYNAMIC_PORT_MIN 0x40
	31	#define DYNAMIC_PORT_MAX 0x7f
	32
	33	static DEFINE_SEQLOCK(local_port_range_lock);
	34	static int local_port_range_min[2] = {0, 0};
	35	static int local_port_range_max[2] = {1023, 1023};
	36	static int local_port_range[2] = {DYNAMIC_PORT_MIN, DYNAMIC_PORT_MAX};
	37	static struct ctl_table_header *phonet_table_hrd;
	38
	39	static void set_local_port_range(int range[2])
	40	{
	41	write_seqlock(&local_port_range_lock);
	42	local_port_range[0] = range[0];
	43	local_port_range[1] = range[1];
	44	write_sequnlock(&local_port_range_lock);
	45	}
	46
	47	void phonet_get_local_port_range(int min, int max)
	48	{
	49	unsigned seq;
	50	do {
	51	seq = read_seqbegin(&local_port_range_lock);
	52	if (min)
	53	*min = local_port_range[0];
	54	if (max)
	55	*max = local_port_range[1];
	56	} while (read_seqretry(&local_port_range_lock, seq));
	57	}
	58
8d65af78	59	static int proc_local_port_range(ctl_table *table, int write,
87ab4e20 RDC	60	void __user *buffer,
	61	size_t lenp, loff_t ppos)
	62	{
	63	int ret;
	64	int range[2] = {local_port_range[0], local_port_range[1]};
	65	ctl_table tmp = {
	66	.data = &range,
	67	.maxlen = sizeof(range),
	68	.mode = table->mode,
	69	.extra1 = &local_port_range_min,
	70	.extra2 = &local_port_range_max,
	71	};
	72
8d65af78	73	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
87ab4e20 RDC	74
	75	if (write && ret == 0) {
	76	if (range[1] < range[0])
	77	ret = -EINVAL;
	78	else
	79	set_local_port_range(range);
	80	}
	81
	82	return ret;
	83	}
	84
	85	static struct ctl_table phonet_table[] = {
	86	{
	87	.ctl_name = CTL_UNNUMBERED,
	88	.procname = "local_port_range",
	89	.data = &local_port_range,
	90	.maxlen = sizeof(local_port_range),
	91	.mode = 0644,
6d9f239a	92	.proc_handler = proc_local_port_range,
87ab4e20 RDC	93	.strategy = NULL,
	94	},
	95	{ .ctl_name = 0 }
	96	};
	97
5eaa65b2	98	static struct ctl_path phonet_ctl_path[] = {
87ab4e20 RDC	99	{ .procname = "net", .ctl_name = CTL_NET, },
	100	{ .procname = "phonet", .ctl_name = CTL_UNNUMBERED, },
	101	{ },
	102	};
	103
	104	int __init phonet_sysctl_init(void)
	105	{
	106	phonet_table_hrd = register_sysctl_paths(phonet_ctl_path, phonet_table);
	107	return phonet_table_hrd == NULL ? -ENOMEM : 0;
	108	}
	109
	110	void phonet_sysctl_exit(void)
	111	{
	112	unregister_sysctl_table(phonet_table_hrd);
	113	}