/*
 * Copyright (C) 2013 Altera Corporation
 * Copyright (C) 2011-2012 Tobias Klauser <tklauser@distanz.ch>
 * Copyright (C) 2004 Microtronix Datacom Ltd.
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 */

#include <linux/export.h>
#include <linux/file.h>
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/syscalls.h>

#include <asm/cacheflush.h>
#include <asm/traps.h>

/* sys_cacheflush -- flush the processor cache. */
asmlinkage int sys_cacheflush(unsigned long addr, unsigned long len,
                                unsigned int op)
{
        struct vm_area_struct *vma;
        struct mm_struct *mm = current->mm;

        if (len == 0)
                return 0;

        /* We only support op 0 now, return error if op is non-zero.*/
        if (op)
                return -EINVAL;

        /* Check for overflow */
        if (addr + len < addr)
                return -EFAULT;

        if (mmap_read_lock_killable(mm))
                return -EINTR;

        /*
         * Verify that the specified address region actually belongs
         * to this process.
         */
        vma = find_vma(mm, addr);
        if (vma == NULL || addr < vma->vm_start || addr + len > vma->vm_end) {
                mmap_read_unlock(mm);
                return -EFAULT;
        }

        flush_cache_range(vma, addr, addr + len);

        mmap_read_unlock(mm);
        return 0;
}

asmlinkage int sys_getpagesize(void)
{
        return PAGE_SIZE;
}