1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
|
#ifndef _ASM_POWERPC_CHECKSUM_H
#define _ASM_POWERPC_CHECKSUM_H
#ifdef __KERNEL__
/*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#ifdef CONFIG_GENERIC_CSUM
#include <asm-generic/checksum.h>
#else
#include <linux/bitops.h>
#include <linux/in6.h>
/*
* Computes the checksum of a memory block at src, length len,
* and adds in "sum" (32-bit), while copying the block to dst.
* If an access exception occurs on src or dst, it stores -EFAULT
* to *src_err or *dst_err respectively (if that pointer is not
* NULL), and, for an error on src, zeroes the rest of dst.
*
* Like csum_partial, this must be called with even lengths,
* except for the last fragment.
*/
extern __wsum csum_partial_copy_generic(const void *src, void *dst,
int len, __wsum sum,
int *src_err, int *dst_err);
#define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER
extern __wsum csum_and_copy_from_user(const void __user *src, void *dst,
int len, __wsum sum, int *err_ptr);
#define HAVE_CSUM_COPY_USER
extern __wsum csum_and_copy_to_user(const void *src, void __user *dst,
int len, __wsum sum, int *err_ptr);
#define csum_partial_copy_nocheck(src, dst, len, sum) \
csum_partial_copy_generic((src), (dst), (len), (sum), NULL, NULL)
/*
* turns a 32-bit partial checksum (e.g. from csum_partial) into a
* 1's complement 16-bit checksum.
*/
static inline __sum16 csum_fold(__wsum sum)
{
unsigned int tmp;
/* swap the two 16-bit halves of sum */
__asm__("rlwinm %0,%1,16,0,31" : "=r" (tmp) : "r" (sum));
/* if there is a carry from adding the two 16-bit halves,
it will carry from the lower half into the upper half,
giving us the correct sum in the upper half. */
return (__force __sum16)(~((__force u32)sum + tmp) >> 16);
}
static inline u32 from64to32(u64 x)
{
return (x + ror64(x, 32)) >> 32;
}
static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr, __u32 len,
__u8 proto, __wsum sum)
{
#ifdef __powerpc64__
u64 s = (__force u32)sum;
s += (__force u32)saddr;
s += (__force u32)daddr;
#ifdef __BIG_ENDIAN__
s += proto + len;
#else
s += (proto + len) << 8;
#endif
return (__force __wsum) from64to32(s);
#else
__asm__("\n\
addc %0,%0,%1 \n\
adde %0,%0,%2 \n\
adde %0,%0,%3 \n\
addze %0,%0 \n\
"
: "=r" (sum)
: "r" (daddr), "r"(saddr), "r"(proto + len), "0"(sum));
return sum;
#endif
}
/*
* computes the checksum of the TCP/UDP pseudo-header
* returns a 16-bit checksum, already complemented
*/
static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr, __u32 len,
__u8 proto, __wsum sum)
{
return csum_fold(csum_tcpudp_nofold(saddr, daddr, len, proto, sum));
}
#define HAVE_ARCH_CSUM_ADD
static inline __wsum csum_add(__wsum csum, __wsum addend)
{
#ifdef __powerpc64__
u64 res = (__force u64)csum;
#endif
if (__builtin_constant_p(csum) && csum == 0)
return addend;
if (__builtin_constant_p(addend) && addend == 0)
return csum;
#ifdef __powerpc64__
res += (__force u64)addend;
return (__force __wsum)((u32)res + (res >> 32));
#else
asm("addc %0,%0,%1;"
"addze %0,%0;"
: "+r" (csum) : "r" (addend) : "xer");
return csum;
#endif
}
/*
* This is a version of ip_compute_csum() optimized for IP headers,
* which always checksum on 4 octet boundaries. ihl is the number
* of 32-bit words and is always >= 5.
*/
static inline __wsum ip_fast_csum_nofold(const void *iph, unsigned int ihl)
{
const u32 *ptr = (const u32 *)iph + 1;
#ifdef __powerpc64__
unsigned int i;
u64 s = *(const u32 *)iph;
for (i = 0; i < ihl - 1; i++, ptr++)
s += *ptr;
return (__force __wsum)from64to32(s);
#else
__wsum sum, tmp;
asm("mtctr %3;"
"addc %0,%4,%5;"
"1: lwzu %1, 4(%2);"
"adde %0,%0,%1;"
"bdnz 1b;"
"addze %0,%0;"
: "=r" (sum), "=r" (tmp), "+b" (ptr)
: "r" (ihl - 2), "r" (*(const u32 *)iph), "r" (*ptr)
: "ctr", "xer", "memory");
return sum;
#endif
}
static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl)
{
return csum_fold(ip_fast_csum_nofold(iph, ihl));
}
/*
* computes the checksum of a memory block at buff, length len,
* and adds in "sum" (32-bit)
*
* returns a 32-bit number suitable for feeding into itself
* or csum_tcpudp_magic
*
* this function must be called with even lengths, except
* for the last fragment, which may be odd
*
* it's best to have buff aligned on a 32-bit boundary
*/
__wsum __csum_partial(const void *buff, int len, __wsum sum);
static inline __wsum csum_partial(const void *buff, int len, __wsum sum)
{
if (__builtin_constant_p(len) && len <= 16 && (len & 1) == 0) {
if (len == 2)
sum = csum_add(sum, (__force __wsum)*(const u16 *)buff);
if (len >= 4)
sum = csum_add(sum, (__force __wsum)*(const u32 *)buff);
if (len == 6)
sum = csum_add(sum, (__force __wsum)
*(const u16 *)(buff + 4));
if (len >= 8)
sum = csum_add(sum, (__force __wsum)
*(const u32 *)(buff + 4));
if (len == 10)
sum = csum_add(sum, (__force __wsum)
*(const u16 *)(buff + 8));
if (len >= 12)
sum = csum_add(sum, (__force __wsum)
*(const u32 *)(buff + 8));
if (len == 14)
sum = csum_add(sum, (__force __wsum)
*(const u16 *)(buff + 12));
if (len >= 16)
sum = csum_add(sum, (__force __wsum)
*(const u32 *)(buff + 12));
} else if (__builtin_constant_p(len) && (len & 3) == 0) {
sum = csum_add(sum, ip_fast_csum_nofold(buff, len >> 2));
} else {
sum = __csum_partial(buff, len, sum);
}
return sum;
}
/*
* this routine is used for miscellaneous IP-like checksums, mainly
* in icmp.c
*/
static inline __sum16 ip_compute_csum(const void *buff, int len)
{
return csum_fold(csum_partial(buff, len, 0));
}
#define _HAVE_ARCH_IPV6_CSUM
__sum16 csum_ipv6_magic(const struct in6_addr *saddr,
const struct in6_addr *daddr,
__u32 len, __u8 proto, __wsum sum);
#endif
#endif /* __KERNEL__ */
#endif
|
