kernel_optimize_test/arch/hexagon/mm/uaccess.c
Thomas Gleixner 08dbd0f8ef treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 267
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 and
  only version 2 as published by the free software foundation this
  program is distributed in the hope that it will be useful but
  without any warranty without even the implied warranty of
  merchantability or fitness for a particular purpose see the gnu
  general public license for more details you should have received a
  copy of the gnu general public license along with this program if
  not write to the free software foundation inc 51 franklin street
  fifth floor boston ma 02110 1301 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 94 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141334.043630402@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:30:29 +02:00

46 lines
1.1 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2010-2011, The Linux Foundation. All rights reserved.
*/
/*
* Support for user memory access from kernel. This will
* probably be inlined for performance at some point, but
* for ease of debug, and to a lesser degree for code size,
* we implement here as subroutines.
*/
#include <linux/types.h>
#include <linux/uaccess.h>
#include <asm/pgtable.h>
/*
* For clear_user(), exploit previously defined copy_to_user function
* and the fact that we've got a handy zero page defined in kernel/head.S
*
* dczero here would be even faster.
*/
__kernel_size_t __clear_user_hexagon(void __user *dest, unsigned long count)
{
long uncleared;
while (count > PAGE_SIZE) {
uncleared = raw_copy_to_user(dest, &empty_zero_page, PAGE_SIZE);
if (uncleared)
return count - (PAGE_SIZE - uncleared);
count -= PAGE_SIZE;
dest += PAGE_SIZE;
}
if (count)
count = raw_copy_to_user(dest, &empty_zero_page, count);
return count;
}
unsigned long clear_user_hexagon(void __user *dest, unsigned long count)
{
if (!access_ok(dest, count))
return count;
else
return __clear_user_hexagon(dest, count);
}