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1394f032 BW |
1 | #ifndef _BFIN_CHECKSUM_H |
2 | #define _BFIN_CHECKSUM_H | |
3 | ||
4 | /* | |
5 | * MODIFIED FOR BFIN April 30, 2001 akbar.hussain@lineo.com | |
6 | * | |
7 | * computes the checksum of a memory block at buff, length len, | |
8 | * and adds in "sum" (32-bit) | |
9 | * | |
10 | * returns a 32-bit number suitable for feeding into itself | |
11 | * or csum_tcpudp_magic | |
12 | * | |
13 | * this function must be called with even lengths, except | |
14 | * for the last fragment, which may be odd | |
15 | * | |
16 | * it's best to have buff aligned on a 32-bit boundary | |
17 | */ | |
18 | unsigned int csum_partial(const unsigned char *buff, int len, unsigned int sum); | |
19 | ||
20 | /* | |
21 | * the same as csum_partial, but copies from src while it | |
22 | * checksums | |
23 | * | |
24 | * here even more important to align src and dst on a 32-bit (or even | |
25 | * better 64-bit) boundary | |
26 | */ | |
27 | ||
28 | unsigned int csum_partial_copy(const unsigned char *src, unsigned char *dst, | |
29 | int len, int sum); | |
30 | ||
31 | /* | |
32 | * the same as csum_partial_copy, but copies from user space. | |
33 | * | |
34 | * here even more important to align src and dst on a 32-bit (or even | |
35 | * better 64-bit) boundary | |
36 | */ | |
37 | ||
38 | extern unsigned int csum_partial_copy_from_user(const unsigned char *src, | |
39 | unsigned char *dst, int len, | |
40 | int sum, int *csum_err); | |
41 | ||
42 | #define csum_partial_copy_nocheck(src, dst, len, sum) \ | |
43 | csum_partial_copy((src), (dst), (len), (sum)) | |
44 | ||
45 | unsigned short ip_fast_csum(unsigned char *iph, unsigned int ihl); | |
46 | ||
47 | /* | |
48 | * Fold a partial checksum | |
49 | */ | |
50 | ||
51 | static inline unsigned int csum_fold(unsigned int sum) | |
52 | { | |
53 | while (sum >> 16) | |
54 | sum = (sum & 0xffff) + (sum >> 16); | |
55 | return ((~(sum << 16)) >> 16); | |
56 | } | |
57 | ||
58 | /* | |
59 | * computes the checksum of the TCP/UDP pseudo-header | |
60 | * returns a 16-bit checksum, already complemented | |
61 | */ | |
62 | ||
63 | static inline unsigned int | |
64 | csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr, unsigned short len, | |
65 | unsigned short proto, unsigned int sum) | |
66 | { | |
67 | ||
68 | __asm__ ("%0 = %0 + %1;\n\t" | |
69 | "CC = AC0;\n\t" | |
70 | "if !CC jump 4;\n\t" | |
71 | "%0 = %0 + %4;\n\t" | |
72 | "%0 = %0 + %2;\n\t" | |
73 | "CC = AC0;\n\t" | |
74 | "if !CC jump 4;\n\t" | |
75 | "%0 = %0 + %4;\n\t" | |
76 | "%0 = %0 + %3;\n\t" | |
77 | "CC = AC0;\n\t" | |
78 | "if !CC jump 4;\n\t" | |
79 | "%0 = %0 + %4;\n\t" | |
80 | "NOP;\n\t" | |
81 | : "=d" (sum) | |
82 | : "d" (daddr), "d" (saddr), "d" ((ntohs(len)<<16)+proto*256), "d" (1), "0"(sum)); | |
83 | ||
84 | return (sum); | |
85 | } | |
86 | ||
87 | static inline unsigned short int | |
88 | csum_tcpudp_magic(unsigned long saddr, unsigned long daddr, unsigned short len, | |
89 | unsigned short proto, unsigned int sum) | |
90 | { | |
91 | return csum_fold(csum_tcpudp_nofold(saddr, daddr, len, proto, sum)); | |
92 | } | |
93 | ||
94 | /* | |
95 | * this routine is used for miscellaneous IP-like checksums, mainly | |
96 | * in icmp.c | |
97 | */ | |
98 | ||
99 | extern unsigned short ip_compute_csum(const unsigned char *buff, int len); | |
100 | ||
101 | #endif /* _BFIN_CHECKSUM_H */ |