LXR linux/arch/nios2/kernel/sys

   1/*
   2 * Copyright (C) 2013 Altera Corporation
   3 * Copyright (C) 2011-2012 Tobias Klauser <tklauser@distanz.ch>
   4 * Copyright (C) 2004 Microtronix Datacom Ltd.
   5 *
   6 * This file is subject to the terms and conditions of the GNU General Public
   7 * License.  See the file "COPYING" in the main directory of this archive
   8 * for more details.
   9 */
  10
  11#include <linux/export.h>
  12#include <linux/file.h>
  13#include <linux/fs.h>
  14#include <linux/slab.h>
  15#include <linux/syscalls.h>
  16
  17#include <asm/cacheflush.h>
  18#include <asm/traps.h>
  19
  20/* sys_cacheflush -- flush the processor cache. */
  21asmlinkage int sys_cacheflush(unsigned long addr, unsigned long len,
  22                                unsigned int op)
  23{
  24        struct vm_area_struct *vma;
  25
  26        if (len == 0)
  27                return 0;
  28
  29        /* We only support op 0 now, return error if op is non-zero.*/
  30        if (op)
  31                return -EINVAL;
  32
  33        /* Check for overflow */
  34        if (addr + len < addr)
  35                return -EFAULT;
  36
  37        /*
  38         * Verify that the specified address region actually belongs
  39         * to this process.
  40         */
  41        vma = find_vma(current->mm, addr);
  42        if (vma == NULL || addr < vma->vm_start || addr + len > vma->vm_end)
  43                return -EFAULT;
  44
  45        flush_cache_range(vma, addr, addr + len);
  46
  47        return 0;
  48}
  49
  50asmlinkage int sys_getpagesize(void)
  51{
  52        return PAGE_SIZE;
  53}
  54