1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * MIPS64 specific IP/TCP/UDP checksumming routines
7  *
8  * Copyright (C) 1998, 1999 Ralf Baechle
9  */
10 #include <net/checksum.h>
11 #include <linux/types.h>
12 #include <asm/byteorder.h>
13 #include <asm/string.h>
14 #include <asm/uaccess.h>
15 
16 /*
17  * copy while checksumming, otherwise like csum_partial
18  */
csum_partial_copy(const char * src,char * dst,int len,unsigned int sum)19 unsigned int csum_partial_copy(const char *src, char *dst,
20                                int len, unsigned int sum)
21 {
22 	/*
23 	 * It's 2:30 am and I don't feel like doing it real ...
24 	 * This is lots slower than the real thing (tm)
25 	 */
26 	sum = csum_partial(src, len, sum);
27 	memcpy(dst, src, len);
28 
29 	return sum;
30 }
31 
32 /*
33  * Copy from userspace and compute checksum.  If we catch an exception
34  * then zero the rest of the buffer.
35  */
csum_partial_copy_from_user(const char * src,char * dst,int len,unsigned int sum,int * err_ptr)36 unsigned int csum_partial_copy_from_user (const char *src, char *dst,
37                                           int len, unsigned int sum,
38                                           int *err_ptr)
39 {
40 	int missing;
41 
42 	missing = copy_from_user(dst, src, len);
43 	if (missing) {
44 		memset(dst + len - missing, 0, missing);
45 		*err_ptr = -EFAULT;
46 	}
47 
48 	return csum_partial(dst, len, sum);
49 }
50