Commit | Line | Data |
---|---|---|
d95bbcb3 KG |
1 | #ifndef _ASM_POWERPC_CHECKSUM_H |
2 | #define _ASM_POWERPC_CHECKSUM_H | |
88ced031 | 3 | #ifdef __KERNEL__ |
1da177e4 LT |
4 | |
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 | /* | |
13 | * This is a version of ip_compute_csum() optimized for IP headers, | |
14 | * which always checksum on 4 octet boundaries. ihl is the number | |
15 | * of 32-bit words and is always >= 5. | |
16 | */ | |
879178cf | 17 | extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl); |
1da177e4 LT |
18 | |
19 | /* | |
20 | * computes the checksum of the TCP/UDP pseudo-header | |
21 | * returns a 16-bit checksum, already complemented | |
22 | */ | |
879178cf | 23 | extern __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr, |
1da177e4 LT |
24 | unsigned short len, |
25 | unsigned short proto, | |
879178cf | 26 | __wsum sum); |
1da177e4 LT |
27 | |
28 | /* | |
29 | * computes the checksum of a memory block at buff, length len, | |
30 | * and adds in "sum" (32-bit) | |
31 | * | |
32 | * returns a 32-bit number suitable for feeding into itself | |
33 | * or csum_tcpudp_magic | |
34 | * | |
35 | * this function must be called with even lengths, except | |
36 | * for the last fragment, which may be odd | |
37 | * | |
38 | * it's best to have buff aligned on a 32-bit boundary | |
39 | */ | |
879178cf | 40 | extern __wsum csum_partial(const void *buff, int len, __wsum sum); |
1da177e4 LT |
41 | |
42 | /* | |
d95bbcb3 KG |
43 | * Computes the checksum of a memory block at src, length len, |
44 | * and adds in "sum" (32-bit), while copying the block to dst. | |
45 | * If an access exception occurs on src or dst, it stores -EFAULT | |
46 | * to *src_err or *dst_err respectively (if that pointer is not | |
47 | * NULL), and, for an error on src, zeroes the rest of dst. | |
48 | * | |
49 | * Like csum_partial, this must be called with even lengths, | |
50 | * except for the last fragment. | |
1da177e4 | 51 | */ |
879178cf AV |
52 | extern __wsum csum_partial_copy_generic(const void *src, void *dst, |
53 | int len, __wsum sum, | |
1da177e4 LT |
54 | int *src_err, int *dst_err); |
55 | /* | |
56 | * the same as csum_partial, but copies from src to dst while it | |
57 | * checksums. | |
58 | */ | |
d95bbcb3 | 59 | #define csum_partial_copy_from_user(src, dst, len, sum, errp) \ |
879178cf | 60 | csum_partial_copy_generic((__force const void *)(src), (dst), (len), (sum), (errp), NULL) |
d95bbcb3 KG |
61 | |
62 | #define csum_partial_copy_nocheck(src, dst, len, sum) \ | |
63 | csum_partial_copy_generic((src), (dst), (len), (sum), NULL, NULL) | |
64 | ||
65 | ||
1da177e4 LT |
66 | /* |
67 | * turns a 32-bit partial checksum (e.g. from csum_partial) into a | |
68 | * 1's complement 16-bit checksum. | |
69 | */ | |
879178cf | 70 | static inline __sum16 csum_fold(__wsum sum) |
1da177e4 LT |
71 | { |
72 | unsigned int tmp; | |
73 | ||
74 | /* swap the two 16-bit halves of sum */ | |
75 | __asm__("rlwinm %0,%1,16,0,31" : "=r" (tmp) : "r" (sum)); | |
76 | /* if there is a carry from adding the two 16-bit halves, | |
77 | it will carry from the lower half into the upper half, | |
78 | giving us the correct sum in the upper half. */ | |
879178cf | 79 | return (__force __sum16)(~((__force u32)sum + tmp) >> 16); |
1da177e4 LT |
80 | } |
81 | ||
82 | /* | |
83 | * this routine is used for miscellaneous IP-like checksums, mainly | |
84 | * in icmp.c | |
85 | */ | |
879178cf | 86 | static inline __sum16 ip_compute_csum(const void *buff, int len) |
1da177e4 LT |
87 | { |
88 | return csum_fold(csum_partial(buff, len, 0)); | |
89 | } | |
90 | ||
879178cf | 91 | static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr, |
1da177e4 LT |
92 | unsigned short len, |
93 | unsigned short proto, | |
879178cf | 94 | __wsum sum) |
1da177e4 | 95 | { |
879178cf AV |
96 | #ifdef __powerpc64__ |
97 | unsigned long s = (__force u32)sum; | |
1da177e4 | 98 | |
879178cf AV |
99 | s += (__force u32)saddr; |
100 | s += (__force u32)daddr; | |
101 | s += proto + len; | |
1da177e4 | 102 | s += (s >> 32); |
879178cf | 103 | return (__force __wsum) s; |
d95bbcb3 | 104 | #else |
d95bbcb3 KG |
105 | __asm__("\n\ |
106 | addc %0,%0,%1 \n\ | |
107 | adde %0,%0,%2 \n\ | |
108 | adde %0,%0,%3 \n\ | |
109 | addze %0,%0 \n\ | |
110 | " | |
111 | : "=r" (sum) | |
879178cf AV |
112 | : "r" (daddr), "r"(saddr), "r"(proto + len), "0"(sum)); |
113 | return sum; | |
1da177e4 | 114 | #endif |
879178cf | 115 | } |
88ced031 | 116 | #endif /* __KERNEL__ */ |
d95bbcb3 | 117 | #endif |