mq_sysctl.c

Go to the documentation of this file.

/*
 *  Copyright (C) 2007 IBM Corporation
 *
 *  Author: Cedric Le Goater <[email protected]>
 *
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU General Public License as
 *  published by the Free Software Foundation, version 2 of the
 *  License.
 */

#include <linux/nsproxy.h>
#include <linux/ipc_namespace.h>
#include <linux/sysctl.h>

#ifdef CONFIG_PROC_SYSCTL
static void *get_mq(ctl_table *table)
{
    char *which = table->data;
    struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns;
    which = (which - (char *)&init_ipc_ns) + (char *)ipc_ns;
    return which;
}

static int proc_mq_dointvec_minmax(ctl_table *table, int write,
    void __user *buffer, size_t *lenp, loff_t *ppos)
{
    struct ctl_table mq_table;
    memcpy(&mq_table, table, sizeof(mq_table));
    mq_table.data = get_mq(table);

    return proc_dointvec_minmax(&mq_table, write, buffer,
                    lenp, ppos);
}
#else
#define proc_mq_dointvec_minmax NULL
#endif

static int msg_queues_limit_min = MIN_QUEUESMAX;
static int msg_queues_limit_max = HARD_QUEUESMAX;

static int msg_max_limit_min = MIN_MSGMAX;
static int msg_max_limit_max = HARD_MSGMAX;

static int msg_maxsize_limit_min = MIN_MSGSIZEMAX;
static int msg_maxsize_limit_max = HARD_MSGSIZEMAX;

static ctl_table mq_sysctls[] = {
    {
        .procname   = "queues_max",
        .data       = &init_ipc_ns.mq_queues_max,
        .maxlen     = sizeof(int),
        .mode       = 0644,
        .proc_handler   = proc_mq_dointvec_minmax,
        .extra1     = &msg_queues_limit_min,
        .extra2     = &msg_queues_limit_max,
    },
    {
        .procname   = "msg_max",
        .data       = &init_ipc_ns.mq_msg_max,
        .maxlen     = sizeof(int),
        .mode       = 0644,
        .proc_handler   = proc_mq_dointvec_minmax,
        .extra1     = &msg_max_limit_min,
        .extra2     = &msg_max_limit_max,
    },
    {
        .procname   = "msgsize_max",
        .data       = &init_ipc_ns.mq_msgsize_max,
        .maxlen     = sizeof(int),
        .mode       = 0644,
        .proc_handler   = proc_mq_dointvec_minmax,
        .extra1     = &msg_maxsize_limit_min,
        .extra2     = &msg_maxsize_limit_max,
    },
    {
        .procname   = "msg_default",
        .data       = &init_ipc_ns.mq_msg_default,
        .maxlen     = sizeof(int),
        .mode       = 0644,
        .proc_handler   = proc_mq_dointvec_minmax,
        .extra1     = &msg_max_limit_min,
        .extra2     = &msg_max_limit_max,
    },
    {
        .procname   = "msgsize_default",
        .data       = &init_ipc_ns.mq_msgsize_default,
        .maxlen     = sizeof(int),
        .mode       = 0644,
        .proc_handler   = proc_mq_dointvec_minmax,
        .extra1     = &msg_maxsize_limit_min,
        .extra2     = &msg_maxsize_limit_max,
    },
    {}
};

static ctl_table mq_sysctl_dir[] = {
    {
        .procname   = "mqueue",
        .mode       = 0555,
        .child      = mq_sysctls,
    },
    {}
};

static ctl_table mq_sysctl_root[] = {
    {
        .procname   = "fs",
        .mode       = 0555,
        .child      = mq_sysctl_dir,
    },
    {}
};

struct ctl_table_header *mq_register_sysctl_table(void)
{
    return register_sysctl_table(mq_sysctl_root);
}