diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-ppc64/checksum.h |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'include/asm-ppc64/checksum.h')
-rw-r--r-- | include/asm-ppc64/checksum.h | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/include/asm-ppc64/checksum.h b/include/asm-ppc64/checksum.h new file mode 100644 index 000000000000..d22d4469de43 --- /dev/null +++ b/include/asm-ppc64/checksum.h | |||
@@ -0,0 +1,107 @@ | |||
1 | #ifndef _PPC64_CHECKSUM_H | ||
2 | #define _PPC64_CHECKSUM_H | ||
3 | |||
4 | /* | ||
5 | * This program is free software; you can redistribute it and/or | ||
6 | * modify it under the terms of the GNU General Public License | ||
7 | * as published by the Free Software Foundation; either version | ||
8 | * 2 of the License, or (at your option) any later version. | ||
9 | */ | ||
10 | |||
11 | /* | ||
12 | * This is a version of ip_compute_csum() optimized for IP headers, | ||
13 | * which always checksum on 4 octet boundaries. ihl is the number | ||
14 | * of 32-bit words and is always >= 5. | ||
15 | */ | ||
16 | extern unsigned short ip_fast_csum(unsigned char * iph, unsigned int ihl); | ||
17 | |||
18 | /* | ||
19 | * computes the checksum of the TCP/UDP pseudo-header | ||
20 | * returns a 16-bit checksum, already complemented | ||
21 | */ | ||
22 | extern unsigned short csum_tcpudp_magic(unsigned long saddr, | ||
23 | unsigned long daddr, | ||
24 | unsigned short len, | ||
25 | unsigned short proto, | ||
26 | unsigned int sum); | ||
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 | */ | ||
40 | extern unsigned int csum_partial(const unsigned char * buff, int len, | ||
41 | unsigned int sum); | ||
42 | |||
43 | /* | ||
44 | * the same as csum_partial, but copies from src to dst while it | ||
45 | * checksums | ||
46 | */ | ||
47 | extern unsigned int csum_partial_copy_generic(const char *src, char *dst, | ||
48 | int len, unsigned int sum, | ||
49 | int *src_err, int *dst_err); | ||
50 | /* | ||
51 | * the same as csum_partial, but copies from src to dst while it | ||
52 | * checksums. | ||
53 | */ | ||
54 | |||
55 | unsigned int csum_partial_copy_nocheck(const char *src, | ||
56 | char *dst, | ||
57 | int len, | ||
58 | unsigned int sum); | ||
59 | |||
60 | /* | ||
61 | * turns a 32-bit partial checksum (e.g. from csum_partial) into a | ||
62 | * 1's complement 16-bit checksum. | ||
63 | */ | ||
64 | static inline unsigned int csum_fold(unsigned int sum) | ||
65 | { | ||
66 | unsigned int tmp; | ||
67 | |||
68 | /* swap the two 16-bit halves of sum */ | ||
69 | __asm__("rlwinm %0,%1,16,0,31" : "=r" (tmp) : "r" (sum)); | ||
70 | /* if there is a carry from adding the two 16-bit halves, | ||
71 | it will carry from the lower half into the upper half, | ||
72 | giving us the correct sum in the upper half. */ | ||
73 | sum = ~(sum + tmp) >> 16; | ||
74 | return sum; | ||
75 | } | ||
76 | |||
77 | /* | ||
78 | * this routine is used for miscellaneous IP-like checksums, mainly | ||
79 | * in icmp.c | ||
80 | */ | ||
81 | static inline unsigned short ip_compute_csum(unsigned char * buff, int len) | ||
82 | { | ||
83 | return csum_fold(csum_partial(buff, len, 0)); | ||
84 | } | ||
85 | |||
86 | #define csum_partial_copy_from_user(src, dst, len, sum, errp) \ | ||
87 | csum_partial_copy_generic((src), (dst), (len), (sum), (errp), NULL) | ||
88 | |||
89 | #define csum_partial_copy_nocheck(src, dst, len, sum) \ | ||
90 | csum_partial_copy_generic((src), (dst), (len), (sum), NULL, NULL) | ||
91 | |||
92 | static inline u32 csum_tcpudp_nofold(u32 saddr, | ||
93 | u32 daddr, | ||
94 | unsigned short len, | ||
95 | unsigned short proto, | ||
96 | unsigned int sum) | ||
97 | { | ||
98 | unsigned long s = sum; | ||
99 | |||
100 | s += saddr; | ||
101 | s += daddr; | ||
102 | s += (proto << 16) + len; | ||
103 | s += (s >> 32); | ||
104 | return (u32) s; | ||
105 | } | ||
106 | |||
107 | #endif | ||