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(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
  25 static 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
  35 static 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
  50 static int msg_max_limit_min = MIN_MSGMAX;
  51 static int msg_max_limit_max = HARD_MSGMAX;
  52
  53 static int msg_maxsize_limit_min = MIN_MSGSIZEMAX;
  54 static int msg_maxsize_limit_max = HARD_MSGSIZEMAX;
  55
  56 static 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
 103 static struct ctl_table mq_sysctl_dir[] = {
 104         {
 105                 .procname       = "mqueue",
 106                 .mode           = 0555,
 107                 .child          = mq_sysctls,
 108         },
 109         {}
 110 };
 111
 112 static struct ctl_table mq_sysctl_root[] = {
 113         {
 114                 .procname       = "fs",
 115                 .mode           = 0555,
 116                 .child          = mq_sysctl_dir,
 117         },
 118         {}
 119 };
 120
 121 struct ctl_table_header *mq_register_sysctl_table(void)
 122 {
 123         return register_sysctl_table(mq_sysctl_root);
 124 }