ipc/mq_sysctl.c

   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
  17 static 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
  25 static 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
  39 static int msg_queues_limit_min = MIN_QUEUESMAX;
  40 static int msg_queues_limit_max = HARD_QUEUESMAX;
  41
  42 static int msg_max_limit_min = MIN_MSGMAX;
  43 static int msg_max_limit_max = HARD_MSGMAX;
  44
  45 static int msg_maxsize_limit_min = MIN_MSGSIZEMAX;
  46 static int msg_maxsize_limit_max = HARD_MSGSIZEMAX;
  47
  48 static 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                 .procname       = "msg_default",
  78                 .data           = &init_ipc_ns.mq_msg_default,
  79                 .maxlen         = sizeof(int),
  80                 .mode           = 0644,
  81                 .proc_handler   = proc_mq_dointvec_minmax,
  82                 .extra1         = &msg_max_limit_min,
  83                 .extra2         = &msg_max_limit_max,
  84         },
  85         {
  86                 .procname       = "msgsize_default",
  87                 .data           = &init_ipc_ns.mq_msgsize_default,
  88                 .maxlen         = sizeof(int),
  89                 .mode           = 0644,
  90                 .proc_handler   = proc_mq_dointvec_minmax,
  91                 .extra1         = &msg_maxsize_limit_min,
  92                 .extra2         = &msg_maxsize_limit_max,
  93         },
  94         {}
  95 };
  96
  97 static ctl_table mq_sysctl_dir[] = {
  98         {
  99                 .procname       = "mqueue",
 100                 .mode           = 0555,
 101                 .child          = mq_sysctls,
 102         },
 103         {}
 104 };
 105
 106 static ctl_table mq_sysctl_root[] = {
 107         {
 108                 .procname       = "fs",
 109                 .mode           = 0555,
 110                 .child          = mq_sysctl_dir,
 111         },
 112         {}
 113 };
 114
 115 struct ctl_table_header *mq_register_sysctl_table(void)
 116 {
 117         return register_sysctl_table(mq_sysctl_root);
 118 }