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12#ifndef _ASM_CHECKSUM_H
13#define _ASM_CHECKSUM_H
14
15#ifdef CONFIG_GENERIC_CSUM
16#include <asm-generic/checksum.h>
17#else
18
19#include <linux/in6.h>
20
21#include <linux/uaccess.h>
22
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33
34
35__wsum csum_partial(const void *buff, int len, __wsum sum);
36
37__wsum __csum_partial_copy_from_user(const void __user *src, void *dst, int len);
38__wsum __csum_partial_copy_to_user(const void *src, void __user *dst, int len);
39
40#define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER
41static inline
42__wsum csum_and_copy_from_user(const void __user *src, void *dst, int len)
43{
44 might_fault();
45 if (!access_ok(src, len))
46 return 0;
47 return __csum_partial_copy_from_user(src, dst, len);
48}
49
50
51
52
53#define HAVE_CSUM_COPY_USER
54static inline
55__wsum csum_and_copy_to_user(const void *src, void __user *dst, int len)
56{
57 might_fault();
58 if (!access_ok(dst, len))
59 return 0;
60 return __csum_partial_copy_to_user(src, dst, len);
61}
62
63
64
65
66
67#define _HAVE_ARCH_CSUM_AND_COPY
68__wsum __csum_partial_copy_nocheck(const void *src, void *dst, int len);
69static inline __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len)
70{
71 return __csum_partial_copy_nocheck(src, dst, len);
72}
73
74
75
76
77static inline __sum16 csum_fold(__wsum csum)
78{
79 u32 sum = (__force u32)csum;
80
81 sum += (sum << 16);
82 csum = (__force __wsum)(sum < (__force u32)csum);
83 sum >>= 16;
84 sum += (__force u32)csum;
85
86 return (__force __sum16)~sum;
87}
88#define csum_fold csum_fold
89
90
91
92
93
94
95
96
97static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl)
98{
99 const unsigned int *word = iph;
100 const unsigned int *stop = word + ihl;
101 unsigned int csum;
102 int carry;
103
104 csum = word[0];
105 csum += word[1];
106 carry = (csum < word[1]);
107 csum += carry;
108
109 csum += word[2];
110 carry = (csum < word[2]);
111 csum += carry;
112
113 csum += word[3];
114 carry = (csum < word[3]);
115 csum += carry;
116
117 word += 4;
118 do {
119 csum += *word;
120 carry = (csum < *word);
121 csum += carry;
122 word++;
123 } while (word != stop);
124
125 return csum_fold(csum);
126}
127#define ip_fast_csum ip_fast_csum
128
129static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
130 __u32 len, __u8 proto,
131 __wsum sum)
132{
133 unsigned long tmp = (__force unsigned long)sum;
134
135 __asm__(
136 " .set push # csum_tcpudp_nofold\n"
137 " .set noat \n"
138#ifdef CONFIG_32BIT
139 " addu %0, %2 \n"
140 " sltu $1, %0, %2 \n"
141 " addu %0, $1 \n"
142
143 " addu %0, %3 \n"
144 " sltu $1, %0, %3 \n"
145 " addu %0, $1 \n"
146
147 " addu %0, %4 \n"
148 " sltu $1, %0, %4 \n"
149 " addu %0, $1 \n"
150#endif
151#ifdef CONFIG_64BIT
152 " daddu %0, %2 \n"
153 " daddu %0, %3 \n"
154 " daddu %0, %4 \n"
155 " dsll32 $1, %0, 0 \n"
156 " daddu %0, $1 \n"
157 " sltu $1, %0, $1 \n"
158 " dsra32 %0, %0, 0 \n"
159 " addu %0, $1 \n"
160#endif
161 " .set pop"
162 : "=r" (tmp)
163 : "0" ((__force unsigned long)daddr),
164 "r" ((__force unsigned long)saddr),
165#ifdef __MIPSEL__
166 "r" ((proto + len) << 8),
167#else
168 "r" (proto + len),
169#endif
170 "r" ((__force unsigned long)sum));
171
172 return (__force __wsum)tmp;
173}
174#define csum_tcpudp_nofold csum_tcpudp_nofold
175
176
177
178
179
180static inline __sum16 ip_compute_csum(const void *buff, int len)
181{
182 return csum_fold(csum_partial(buff, len, 0));
183}
184
185#define _HAVE_ARCH_IPV6_CSUM
186static __inline__ __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
187 const struct in6_addr *daddr,
188 __u32 len, __u8 proto,
189 __wsum sum)
190{
191 __wsum tmp;
192
193 __asm__(
194 " .set push # csum_ipv6_magic\n"
195 " .set noreorder \n"
196 " .set noat \n"
197 " addu %0, %5 # proto (long in network byte order)\n"
198 " sltu $1, %0, %5 \n"
199 " addu %0, $1 \n"
200
201 " addu %0, %6 # csum\n"
202 " sltu $1, %0, %6 \n"
203 " lw %1, 0(%2) # four words source address\n"
204 " addu %0, $1 \n"
205 " addu %0, %1 \n"
206 " sltu $1, %0, %1 \n"
207
208 " lw %1, 4(%2) \n"
209 " addu %0, $1 \n"
210 " addu %0, %1 \n"
211 " sltu $1, %0, %1 \n"
212
213 " lw %1, 8(%2) \n"
214 " addu %0, $1 \n"
215 " addu %0, %1 \n"
216 " sltu $1, %0, %1 \n"
217
218 " lw %1, 12(%2) \n"
219 " addu %0, $1 \n"
220 " addu %0, %1 \n"
221 " sltu $1, %0, %1 \n"
222
223 " lw %1, 0(%3) \n"
224 " addu %0, $1 \n"
225 " addu %0, %1 \n"
226 " sltu $1, %0, %1 \n"
227
228 " lw %1, 4(%3) \n"
229 " addu %0, $1 \n"
230 " addu %0, %1 \n"
231 " sltu $1, %0, %1 \n"
232
233 " lw %1, 8(%3) \n"
234 " addu %0, $1 \n"
235 " addu %0, %1 \n"
236 " sltu $1, %0, %1 \n"
237
238 " lw %1, 12(%3) \n"
239 " addu %0, $1 \n"
240 " addu %0, %1 \n"
241 " sltu $1, %0, %1 \n"
242
243 " addu %0, $1 # Add final carry\n"
244 " .set pop"
245 : "=&r" (sum), "=&r" (tmp)
246 : "r" (saddr), "r" (daddr),
247 "0" (htonl(len)), "r" (htonl(proto)), "r" (sum));
248
249 return csum_fold(sum);
250}
251
252#include <asm-generic/checksum.h>
253#endif
254
255#endif
256