mq_sysctl.c revision 93e6f119
1/*
2 *  Copyright (C) 2007 IBM Corporation
3 *
4 *  Author: Cedric Le Goater <clg@fr.ibm.com>
5 *
6 *  This program is free software; you can redistribute it and/or
7 *  modify it under the terms of the GNU General Public License as
8 *  published by the Free Software Foundation, version 2 of the
9 *  License.
10 */
11
12#include <linux/nsproxy.h>
13#include <linux/ipc_namespace.h>
14#include <linux/sysctl.h>
15
16#ifdef CONFIG_PROC_SYSCTL
17static void *get_mq(ctl_table *table)
18{
19	char *which = table->data;
20	struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns;
21	which = (which - (char *)&init_ipc_ns) + (char *)ipc_ns;
22	return which;
23}
24
25static int proc_mq_dointvec_minmax(ctl_table *table, int write,
26	void __user *buffer, size_t *lenp, loff_t *ppos)
27{
28	struct ctl_table mq_table;
29	memcpy(&mq_table, table, sizeof(mq_table));
30	mq_table.data = get_mq(table);
31
32	return proc_dointvec_minmax(&mq_table, write, buffer,
33					lenp, ppos);
34}
35#else
36#define proc_mq_dointvec_minmax NULL
37#endif
38
39static int msg_queues_limit_min = MIN_QUEUESMAX;
40static int msg_queues_limit_max = HARD_QUEUESMAX;
41
42static int msg_max_limit_min = MIN_MSGMAX;
43static int msg_max_limit_max = HARD_MSGMAX;
44
45static int msg_maxsize_limit_min = MIN_MSGSIZEMAX;
46static int msg_maxsize_limit_max = HARD_MSGSIZEMAX;
47
48static ctl_table mq_sysctls[] = {
49	{
50		.procname	= "queues_max",
51		.data		= &init_ipc_ns.mq_queues_max,
52		.maxlen		= sizeof(int),
53		.mode		= 0644,
54		.proc_handler	= proc_mq_dointvec_minmax,
55		.extra1		= &msg_queues_limit_min,
56		.extra2		= &msg_queues_limit_max,
57	},
58	{
59		.procname	= "msg_max",
60		.data		= &init_ipc_ns.mq_msg_max,
61		.maxlen		= sizeof(int),
62		.mode		= 0644,
63		.proc_handler	= proc_mq_dointvec_minmax,
64		.extra1		= &msg_max_limit_min,
65		.extra2		= &msg_max_limit_max,
66	},
67	{
68		.procname	= "msgsize_max",
69		.data		= &init_ipc_ns.mq_msgsize_max,
70		.maxlen		= sizeof(int),
71		.mode		= 0644,
72		.proc_handler	= proc_mq_dointvec_minmax,
73		.extra1		= &msg_maxsize_limit_min,
74		.extra2		= &msg_maxsize_limit_max,
75	},
76	{}
77};
78
79static ctl_table mq_sysctl_dir[] = {
80	{
81		.procname	= "mqueue",
82		.mode		= 0555,
83		.child		= mq_sysctls,
84	},
85	{}
86};
87
88static ctl_table mq_sysctl_root[] = {
89	{
90		.procname	= "fs",
91		.mode		= 0555,
92		.child		= mq_sysctl_dir,
93	},
94	{}
95};
96
97struct ctl_table_header *mq_register_sysctl_table(void)
98{
99	return register_sysctl_table(mq_sysctl_root);
100}
101