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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
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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 __asm__(
134 " .set push # csum_tcpudp_nofold\n"
135 " .set noat \n"
136#ifdef CONFIG_32BIT
137 " addu %0, %2 \n"
138 " sltu $1, %0, %2 \n"
139 " addu %0, $1 \n"
140
141 " addu %0, %3 \n"
142 " sltu $1, %0, %3 \n"
143 " addu %0, $1 \n"
144
145 " addu %0, %4 \n"
146 " sltu $1, %0, %4 \n"
147 " addu %0, $1 \n"
148#endif
149#ifdef CONFIG_64BIT
150 " daddu %0, %2 \n"
151 " daddu %0, %3 \n"
152 " daddu %0, %4 \n"
153 " dsll32 $1, %0, 0 \n"
154 " daddu %0, $1 \n"
155 " sltu $1, %0, $1 \n"
156 " dsra32 %0, %0, 0 \n"
157 " addu %0, $1 \n"
158#endif
159 " .set pop"
160 : "=r" (sum)
161 : "0" ((__force unsigned long)daddr),
162 "r" ((__force unsigned long)saddr),
163#ifdef __MIPSEL__
164 "r" ((proto + len) << 8),
165#else
166 "r" (proto + len),
167#endif
168 "r" ((__force unsigned long)sum));
169
170 return sum;
171}
172#define csum_tcpudp_nofold csum_tcpudp_nofold
173
174
175
176
177
178static inline __sum16 ip_compute_csum(const void *buff, int len)
179{
180 return csum_fold(csum_partial(buff, len, 0));
181}
182
183#define _HAVE_ARCH_IPV6_CSUM
184static __inline__ __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
185 const struct in6_addr *daddr,
186 __u32 len, __u8 proto,
187 __wsum sum)
188{
189 __wsum tmp;
190
191 __asm__(
192 " .set push # csum_ipv6_magic\n"
193 " .set noreorder \n"
194 " .set noat \n"
195 " addu %0, %5 # proto (long in network byte order)\n"
196 " sltu $1, %0, %5 \n"
197 " addu %0, $1 \n"
198
199 " addu %0, %6 # csum\n"
200 " sltu $1, %0, %6 \n"
201 " lw %1, 0(%2) # four words source address\n"
202 " addu %0, $1 \n"
203 " addu %0, %1 \n"
204 " sltu $1, %0, %1 \n"
205
206 " lw %1, 4(%2) \n"
207 " addu %0, $1 \n"
208 " addu %0, %1 \n"
209 " sltu $1, %0, %1 \n"
210
211 " lw %1, 8(%2) \n"
212 " addu %0, $1 \n"
213 " addu %0, %1 \n"
214 " sltu $1, %0, %1 \n"
215
216 " lw %1, 12(%2) \n"
217 " addu %0, $1 \n"
218 " addu %0, %1 \n"
219 " sltu $1, %0, %1 \n"
220
221 " lw %1, 0(%3) \n"
222 " addu %0, $1 \n"
223 " addu %0, %1 \n"
224 " sltu $1, %0, %1 \n"
225
226 " lw %1, 4(%3) \n"
227 " addu %0, $1 \n"
228 " addu %0, %1 \n"
229 " sltu $1, %0, %1 \n"
230
231 " lw %1, 8(%3) \n"
232 " addu %0, $1 \n"
233 " addu %0, %1 \n"
234 " sltu $1, %0, %1 \n"
235
236 " lw %1, 12(%3) \n"
237 " addu %0, $1 \n"
238 " addu %0, %1 \n"
239 " sltu $1, %0, %1 \n"
240
241 " addu %0, $1 # Add final carry\n"
242 " .set pop"
243 : "=&r" (sum), "=&r" (tmp)
244 : "r" (saddr), "r" (daddr),
245 "0" (htonl(len)), "r" (htonl(proto)), "r" (sum));
246
247 return csum_fold(sum);
248}
249
250#include <asm-generic/checksum.h>
251#endif
252
253#endif
254