arch/powerpc/lib/checksum_wrappers.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *
   4  * Copyright (C) IBM Corporation, 2010
   5  *
   6  * Author: Anton Blanchard <anton@au.ibm.com>
   7  */
   8 #include <linux/export.h>
   9 #include <linux/compiler.h>
  10 #include <linux/types.h>
  11 #include <asm/checksum.h>
  12 #include <linux/uaccess.h>
  13
  14 __wsum csum_and_copy_from_user(const void __user *src, void *dst,
  15                                int len)
  16 {
  17         __wsum csum;
  18
  19         if (unlikely(!user_read_access_begin(src, len)))
  20                 return 0;
  21
  22         csum = csum_partial_copy_generic((void __force *)src, dst, len);
  23
  24         user_read_access_end();
  25         return csum;
  26 }
  27 EXPORT_SYMBOL(csum_and_copy_from_user);
  28
  29 __wsum csum_and_copy_to_user(const void *src, void __user *dst, int len)
  30 {
  31         __wsum csum;
  32
  33         if (unlikely(!user_write_access_begin(dst, len)))
  34                 return 0;
  35
  36         csum = csum_partial_copy_generic(src, (void __force *)dst, len);
  37
  38         user_write_access_end();
  39         return csum;
  40 }
  41 EXPORT_SYMBOL(csum_and_copy_to_user);