arch/um/kernel/maccess.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2013 Richard Weinberger <richrd@nod.at>
   4  */
   5
   6 #include <linux/uaccess.h>
   7 #include <linux/kernel.h>
   8 #include <os.h>
   9
  10 long probe_kernel_read(void *dst, const void *src, size_t size)
  11 {
  12         void *psrc = (void *)rounddown((unsigned long)src, PAGE_SIZE);
  13
  14         if ((unsigned long)src < PAGE_SIZE || size <= 0)
  15                 return -EFAULT;
  16
  17         if (os_mincore(psrc, size + src - psrc) <= 0)
  18                 return -EFAULT;
  19
  20         return __probe_kernel_read(dst, src, size);
  21 }