Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* checksum.h: FRV checksumming |
2 | * | |
3 | * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. | |
4 | * Written by David Howells (dhowells@redhat.com) | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or | |
7 | * modify it under the terms of the GNU General Public License | |
8 | * as published by the Free Software Foundation; either version | |
9 | * 2 of the License, or (at your option) any later version. | |
10 | */ | |
11 | ||
12 | #ifndef _ASM_CHECKSUM_H | |
13 | #define _ASM_CHECKSUM_H | |
14 | ||
15 | #include <linux/in6.h> | |
16 | ||
17 | /* | |
18 | * computes the checksum of a memory block at buff, length len, | |
19 | * and adds in "sum" (32-bit) | |
20 | * | |
21 | * returns a 32-bit number suitable for feeding into itself | |
22 | * or csum_tcpudp_magic | |
23 | * | |
24 | * this function must be called with even lengths, except | |
25 | * for the last fragment, which may be odd | |
26 | * | |
27 | * it's best to have buff aligned on a 32-bit boundary | |
28 | */ | |
8042c44b | 29 | __wsum csum_partial(const void *buff, int len, __wsum sum); |
1da177e4 LT |
30 | |
31 | /* | |
32 | * the same as csum_partial, but copies from src while it | |
33 | * checksums | |
34 | * | |
35 | * here even more important to align src and dst on a 32-bit (or even | |
36 | * better 64-bit) boundary | |
37 | */ | |
8042c44b | 38 | __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum); |
1da177e4 LT |
39 | |
40 | /* | |
41 | * the same as csum_partial_copy, but copies from user space. | |
42 | * | |
43 | * here even more important to align src and dst on a 32-bit (or even | |
44 | * better 64-bit) boundary | |
45 | */ | |
8042c44b AV |
46 | extern __wsum csum_partial_copy_from_user(const void __user *src, void *dst, |
47 | int len, __wsum sum, int *csum_err); | |
1da177e4 LT |
48 | |
49 | /* | |
50 | * This is a version of ip_compute_csum() optimized for IP headers, | |
51 | * which always checksum on 4 octet boundaries. | |
52 | * | |
53 | */ | |
54 | static inline | |
8042c44b | 55 | __sum16 ip_fast_csum(const void *iph, unsigned int ihl) |
1da177e4 LT |
56 | { |
57 | unsigned int tmp, inc, sum = 0; | |
58 | ||
59 | asm(" addcc gr0,gr0,gr0,icc0\n" /* clear icc0.C */ | |
60 | " subi %1,#4,%1 \n" | |
61 | "0: \n" | |
62 | " ldu.p @(%1,%3),%4 \n" | |
63 | " subicc %2,#1,%2,icc1 \n" | |
64 | " addxcc.p %4,%0,%0,icc0 \n" | |
65 | " bhi icc1,#2,0b \n" | |
66 | ||
67 | /* fold the 33-bit result into 16-bits */ | |
68 | " addxcc gr0,%0,%0,icc0 \n" | |
69 | " srli %0,#16,%1 \n" | |
70 | " sethi #0,%0 \n" | |
71 | " add %1,%0,%0 \n" | |
72 | " srli %0,#16,%1 \n" | |
73 | " add %1,%0,%0 \n" | |
74 | ||
75 | : "=r" (sum), "=r" (iph), "=r" (ihl), "=r" (inc), "=&r"(tmp) | |
76 | : "0" (sum), "1" (iph), "2" (ihl), "3" (4), | |
77 | "m"(*(volatile struct { int _[100]; } *)iph) | |
609a70ac | 78 | : "icc0", "icc1", "memory" |
1da177e4 LT |
79 | ); |
80 | ||
8042c44b | 81 | return (__force __sum16)~sum; |
1da177e4 LT |
82 | } |
83 | ||
84 | /* | |
85 | * Fold a partial checksum | |
86 | */ | |
8042c44b | 87 | static inline __sum16 csum_fold(__wsum sum) |
1da177e4 LT |
88 | { |
89 | unsigned int tmp; | |
90 | ||
91 | asm(" srli %0,#16,%1 \n" | |
92 | " sethi #0,%0 \n" | |
93 | " add %1,%0,%0 \n" | |
94 | " srli %0,#16,%1 \n" | |
95 | " add %1,%0,%0 \n" | |
96 | : "=r"(sum), "=&r"(tmp) | |
97 | : "0"(sum) | |
98 | ); | |
99 | ||
8042c44b | 100 | return (__force __sum16)~sum; |
1da177e4 LT |
101 | } |
102 | ||
103 | /* | |
104 | * computes the checksum of the TCP/UDP pseudo-header | |
105 | * returns a 16-bit checksum, already complemented | |
106 | */ | |
8042c44b AV |
107 | static inline __wsum |
108 | csum_tcpudp_nofold(__be32 saddr, __be32 daddr, unsigned short len, | |
109 | unsigned short proto, __wsum sum) | |
1da177e4 LT |
110 | { |
111 | asm(" addcc %1,%0,%0,icc0 \n" | |
112 | " addxcc %2,%0,%0,icc0 \n" | |
113 | " addxcc %3,%0,%0,icc0 \n" | |
114 | " addxcc gr0,%0,%0,icc0 \n" | |
115 | : "=r" (sum) | |
116 | : "r" (daddr), "r" (saddr), "r" (len + proto), "0"(sum) | |
117 | : "icc0" | |
118 | ); | |
119 | return sum; | |
120 | } | |
121 | ||
8042c44b AV |
122 | static inline __sum16 |
123 | csum_tcpudp_magic(__be32 saddr, __be32 daddr, unsigned short len, | |
124 | unsigned short proto, __wsum sum) | |
1da177e4 LT |
125 | { |
126 | return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum)); | |
127 | } | |
128 | ||
129 | /* | |
130 | * this routine is used for miscellaneous IP-like checksums, mainly | |
131 | * in icmp.c | |
132 | */ | |
8042c44b | 133 | extern __sum16 ip_compute_csum(const void *buff, int len); |
1da177e4 LT |
134 | |
135 | #define _HAVE_ARCH_IPV6_CSUM | |
8042c44b AV |
136 | static inline __sum16 |
137 | csum_ipv6_magic(const struct in6_addr *saddr, const struct in6_addr *daddr, | |
138 | __u32 len, unsigned short proto, __wsum sum) | |
1da177e4 LT |
139 | { |
140 | unsigned long tmp, tmp2; | |
141 | ||
142 | asm(" addcc %2,%0,%0,icc0 \n" | |
143 | ||
144 | /* add up the source addr */ | |
145 | " ldi @(%3,0),%1 \n" | |
146 | " addxcc %1,%0,%0,icc0 \n" | |
147 | " ldi @(%3,4),%2 \n" | |
148 | " addxcc %2,%0,%0,icc0 \n" | |
149 | " ldi @(%3,8),%1 \n" | |
150 | " addxcc %1,%0,%0,icc0 \n" | |
151 | " ldi @(%3,12),%2 \n" | |
152 | " addxcc %2,%0,%0,icc0 \n" | |
153 | ||
154 | /* add up the dest addr */ | |
155 | " ldi @(%4,0),%1 \n" | |
156 | " addxcc %1,%0,%0,icc0 \n" | |
157 | " ldi @(%4,4),%2 \n" | |
158 | " addxcc %2,%0,%0,icc0 \n" | |
159 | " ldi @(%4,8),%1 \n" | |
160 | " addxcc %1,%0,%0,icc0 \n" | |
161 | " ldi @(%4,12),%2 \n" | |
162 | " addxcc %2,%0,%0,icc0 \n" | |
163 | ||
164 | /* fold the 33-bit result into 16-bits */ | |
165 | " addxcc gr0,%0,%0,icc0 \n" | |
166 | " srli %0,#16,%1 \n" | |
167 | " sethi #0,%0 \n" | |
168 | " add %1,%0,%0 \n" | |
169 | " srli %0,#16,%1 \n" | |
170 | " add %1,%0,%0 \n" | |
171 | ||
172 | : "=r" (sum), "=&r" (tmp), "=r" (tmp2) | |
173 | : "r" (saddr), "r" (daddr), "0" (sum), "2" (len + proto) | |
174 | : "icc0" | |
175 | ); | |
176 | ||
8042c44b | 177 | return (__force __sum16)~sum; |
1da177e4 LT |
178 | } |
179 | ||
180 | #endif /* _ASM_CHECKSUM_H */ |