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2
3
4
5#ifndef __UM_SYSDEP_CHECKSUM_H
6#define __UM_SYSDEP_CHECKSUM_H
7
8#include "linux/string.h"
9#include "linux/in6.h"
10#include "asm/uaccess.h"
11
12extern __wsum csum_partial(const void *buff, int len, __wsum sum);
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14
15
16
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18
19
20
21
22static __inline__
23__wsum csum_partial_copy_nocheck(const void *src, void *dst,
24 int len, __wsum sum)
25{
26 memcpy(dst, src, len);
27 return(csum_partial(dst, len, sum));
28}
29
30static __inline__
31__wsum csum_partial_copy_from_user(const void __user *src,
32 void *dst, int len, __wsum sum,
33 int *err_ptr)
34{
35 if (copy_from_user(dst, src, len)) {
36 *err_ptr = -EFAULT;
37 return (__force __wsum)-1;
38 }
39 return csum_partial(dst, len, sum);
40}
41
42
43
44
45
46
47
48
49
50static inline __sum16 csum_fold(__wsum sum)
51{
52 __asm__(
53 " addl %1,%0\n"
54 " adcl $0xffff,%0"
55 : "=r" (sum)
56 : "r" ((__force u32)sum << 16),
57 "0" ((__force u32)sum & 0xffff0000)
58 );
59 return (__force __sum16)(~(__force u32)sum >> 16);
60}
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62
63
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65
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70
71
72
73static inline __wsum
74csum_tcpudp_nofold(__be32 saddr, __be32 daddr, unsigned short len,
75 unsigned short proto, __wsum sum)
76{
77 asm(" addl %1, %0\n"
78 " adcl %2, %0\n"
79 " adcl %3, %0\n"
80 " adcl $0, %0\n"
81 : "=r" (sum)
82 : "g" (daddr), "g" (saddr), "g" ((len + proto) << 8), "0" (sum));
83 return sum;
84}
85
86
87
88
89
90static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
91 unsigned short len,
92 unsigned short proto,
93 __wsum sum)
94{
95 return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum));
96}
97
98
99
100
101
102
103static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl)
104{
105 unsigned int sum;
106
107 asm( " movl (%1), %0\n"
108 " subl $4, %2\n"
109 " jbe 2f\n"
110 " addl 4(%1), %0\n"
111 " adcl 8(%1), %0\n"
112 " adcl 12(%1), %0\n"
113 "1: adcl 16(%1), %0\n"
114 " lea 4(%1), %1\n"
115 " decl %2\n"
116 " jne 1b\n"
117 " adcl $0, %0\n"
118 " movl %0, %2\n"
119 " shrl $16, %0\n"
120 " addw %w2, %w0\n"
121 " adcl $0, %0\n"
122 " notl %0\n"
123 "2:"
124
125
126
127 : "=r" (sum), "=r" (iph), "=r" (ihl)
128 : "1" (iph), "2" (ihl)
129 : "memory");
130 return (__force __sum16)sum;
131}
132
133static inline unsigned add32_with_carry(unsigned a, unsigned b)
134{
135 asm("addl %2,%0\n\t"
136 "adcl $0,%0"
137 : "=r" (a)
138 : "0" (a), "r" (b));
139 return a;
140}
141
142extern __sum16 ip_compute_csum(const void *buff, int len);
143
144#endif
145