linux-imx

/*

 * linux/ipc/msgutil.c

 * Copyright (C) 1999, 2004 Manfred Spraul

 *

 * This file is released under GNU General Public Licence version 2 or

 * (at your option) any later version.

 *

 * See the file COPYING for more details.

 */

​

#include <linux/spinlock.h>

#include <linux/init.h>

#include <linux/security.h>

#include <linux/slab.h>

#include <linux/ipc.h>

#include <linux/msg.h>

#include <linux/ipc_namespace.h>

#include <linux/utsname.h>

#include <linux/proc_ns.h>

#include <linux/uaccess.h>

​

#include "util.h"

​

DEFINE_SPINLOCK(mq_lock);

​

/*

 * The next 2 defines are here bc this is the only file

 * compiled when either CONFIG_SYSVIPC and CONFIG_POSIX_MQUEUE

 * and not CONFIG_IPC_NS.

 */

struct ipc_namespace init_ipc_ns = {

    .count      = REFCOUNT_INIT(1),

    .user_ns = &init_user_ns,

    .ns.inum = PROC_IPC_INIT_INO,

#ifdef CONFIG_IPC_NS

    .ns.ops = &ipcns_operations,

#endif

};

​

struct msg_msgseg {

    struct msg_msgseg *next;

    /* the next part of the message follows immediately */

};

​

#define DATALEN_MSG ((size_t)PAGE_SIZE-sizeof(struct msg_msg))

#define DATALEN_SEG ((size_t)PAGE_SIZE-sizeof(struct msg_msgseg))

​

​

static struct msg_msg *alloc_msg(size_t len)

{

    struct msg_msg *msg;

    struct msg_msgseg **pseg;

    size_t alen;

​

    alen = min(len, DATALEN_MSG);

    msg = kmalloc(sizeof(*msg) + alen, GFP_KERNEL_ACCOUNT);

    if (msg == NULL)

        return NULL;

​

    msg->next = NULL;

    msg->security = NULL;

​

    len -= alen;