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arch
powerpc
lib
checksum_wrappers_64.c
Go to the documentation of this file.
1
/*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
4
* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
9
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
14
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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*
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* Copyright (C) IBM Corporation, 2010
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*
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* Author: Anton Blanchard <
[email protected]
>
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*/
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#include <linux/export.h>
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#include <linux/compiler.h>
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#include <linux/types.h>
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#include <asm/checksum.h>
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#include <asm/uaccess.h>
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__wsum
csum_and_copy_from_user
(
const
void
__user *
src
,
void
*
dst
,
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int
len,
__wsum
sum
,
int
*err_ptr)
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{
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unsigned
int
csum
;
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might_sleep
();
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*err_ptr = 0;
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if
(!len) {
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csum = 0;
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goto
out
;
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}
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if
(
unlikely
((len < 0) || !
access_ok
(
VERIFY_READ
, src, len))) {
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*err_ptr = -
EFAULT
;
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csum = (
__force
unsigned
int
)sum;
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goto
out
;
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}
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csum =
csum_partial_copy_generic
((
void
__force
*)src, dst,
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len, sum, err_ptr,
NULL
);
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if
(
unlikely
(*err_ptr)) {
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int
missing =
__copy_from_user
(dst, src, len);
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if
(missing) {
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memset
(dst + len - missing, 0, missing);
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*err_ptr = -
EFAULT
;
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}
else
{
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*err_ptr = 0;
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}
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csum =
csum_partial
(dst, len, sum);
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}
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out
:
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return
(
__force
__wsum
)
csum
;
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}
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EXPORT_SYMBOL
(
csum_and_copy_from_user
);
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__wsum
csum_and_copy_to_user
(
const
void
*
src
,
void
__user *
dst
,
int
len,
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__wsum
sum
,
int
*err_ptr)
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{
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unsigned
int
csum
;
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might_sleep
();
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*err_ptr = 0;
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if
(!len) {
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csum = 0;
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goto
out
;
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}
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if
(
unlikely
((len < 0) || !
access_ok
(
VERIFY_WRITE
, dst, len))) {
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*err_ptr = -
EFAULT
;
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csum = -1;
/* invalid checksum */
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goto
out
;
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}
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csum =
csum_partial_copy_generic
(src, (
void
__force
*)dst,
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len, sum,
NULL
, err_ptr);
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if
(
unlikely
(*err_ptr)) {
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csum =
csum_partial
(src, len, sum);
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if
(
copy_to_user
(dst, src, len)) {
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*err_ptr = -
EFAULT
;
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csum = -1;
/* invalid checksum */
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}
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}
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out
:
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return
(
__force
__wsum
)
csum
;
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}
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EXPORT_SYMBOL
(
csum_and_copy_to_user
);
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1.8.2