LXR linux/ipc/mq

   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(struct 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(struct 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(&mq_table, write, buffer, lenp, ppos);
  33}
  34
  35static int proc_mq_dointvec_minmax(struct ctl_table *table, int write,
  36        void __user *buffer, size_t *lenp, loff_t *ppos)
  37{
  38        struct ctl_table mq_table;
  39        memcpy(&mq_table, table, sizeof(mq_table));
  40        mq_table.data = get_mq(table);
  41
  42        return proc_dointvec_minmax(&mq_table, write, buffer,
  43                                        lenp, ppos);
  44}
  45#else
  46#define proc_mq_dointvec NULL
  47#define proc_mq_dointvec_minmax NULL
  48#endif
  49
  50static int msg_max_limit_min = MIN_MSGMAX;
  51static int msg_max_limit_max = HARD_MSGMAX;
  52
  53static int msg_maxsize_limit_min = MIN_MSGSIZEMAX;
  54static int msg_maxsize_limit_max = HARD_MSGSIZEMAX;
  55
  56static struct ctl_table mq_sysctls[] = {
  57        {
  58                .procname       = "queues_max",
  59                .data           = &init_ipc_ns.mq_queues_max,
  60                .maxlen         = sizeof(int),
  61                .mode           = 0644,
  62                .proc_handler   = proc_mq_dointvec,
  63        },
  64        {
  65                .procname       = "msg_max",
  66                .data           = &init_ipc_ns.mq_msg_max,
  67                .maxlen         = sizeof(int),
  68                .mode           = 0644,
  69                .proc_handler   = proc_mq_dointvec_minmax,
  70                .extra1         = &msg_max_limit_min,
  71                .extra2         = &msg_max_limit_max,
  72        },
  73        {
  74                .procname       = "msgsize_max",
  75                .data           = &init_ipc_ns.mq_msgsize_max,
  76                .maxlen         = sizeof(int),
  77                .mode           = 0644,
  78                .proc_handler   = proc_mq_dointvec_minmax,
  79                .extra1         = &msg_maxsize_limit_min,
  80                .extra2         = &msg_maxsize_limit_max,
  81        },
  82        {
  83                .procname       = "msg_default",
  84                .data           = &init_ipc_ns.mq_msg_default,
  85                .maxlen         = sizeof(int),
  86                .mode           = 0644,
  87                .proc_handler   = proc_mq_dointvec_minmax,
  88                .extra1         = &msg_max_limit_min,
  89                .extra2         = &msg_max_limit_max,
  90        },
  91        {
  92                .procname       = "msgsize_default",
  93                .data           = &init_ipc_ns.mq_msgsize_default,
  94                .maxlen         = sizeof(int),
  95                .mode           = 0644,
  96                .proc_handler   = proc_mq_dointvec_minmax,
  97                .extra1         = &msg_maxsize_limit_min,
  98                .extra2         = &msg_maxsize_limit_max,
  99        },
 100        {}
 101};
 102
 103static struct ctl_table mq_sysctl_dir[] = {
 104        {
 105                .procname       = "mqueue",
 106                .mode           = 0555,
 107                .child          = mq_sysctls,
 108        },
 109        {}
 110};
 111
 112static struct ctl_table mq_sysctl_root[] = {
 113        {
 114                .procname       = "fs",
 115                .mode           = 0555,
 116                .child          = mq_sysctl_dir,
 117        },
 118        {}
 119};
 120
 121struct ctl_table_header *mq_register_sysctl_table(void)
 122{
 123        return register_sysctl_table(mq_sysctl_root);
 124}
 125