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-arm26/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-arm26/checksum.h')
-rw-r--r-- | include/asm-arm26/checksum.h | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/include/asm-arm26/checksum.h b/include/asm-arm26/checksum.h new file mode 100644 index 000000000000..d4256d5f3a7c --- /dev/null +++ b/include/asm-arm26/checksum.h | |||
@@ -0,0 +1,160 @@ | |||
1 | /* | ||
2 | * linux/include/asm-arm/checksum.h | ||
3 | * | ||
4 | * IP checksum routines | ||
5 | * | ||
6 | * Copyright (C) Original authors of ../asm-i386/checksum.h | ||
7 | * Copyright (C) 1996-1999 Russell King | ||
8 | */ | ||
9 | #ifndef __ASM_ARM_CHECKSUM_H | ||
10 | #define __ASM_ARM_CHECKSUM_H | ||
11 | |||
12 | #include <linux/in6.h> | ||
13 | |||
14 | /* | ||
15 | * computes the checksum of a memory block at buff, length len, | ||
16 | * and adds in "sum" (32-bit) | ||
17 | * | ||
18 | * returns a 32-bit number suitable for feeding into itself | ||
19 | * or csum_tcpudp_magic | ||
20 | * | ||
21 | * this function must be called with even lengths, except | ||
22 | * for the last fragment, which may be odd | ||
23 | * | ||
24 | * it's best to have buff aligned on a 32-bit boundary | ||
25 | */ | ||
26 | unsigned int csum_partial(const unsigned char * buff, int len, unsigned int sum); | ||
27 | |||
28 | /* | ||
29 | * the same as csum_partial, but copies from src while it | ||
30 | * checksums, and handles user-space pointer exceptions correctly, when needed. | ||
31 | * | ||
32 | * here even more important to align src and dst on a 32-bit (or even | ||
33 | * better 64-bit) boundary | ||
34 | */ | ||
35 | |||
36 | unsigned int | ||
37 | csum_partial_copy_nocheck(const char *src, char *dst, int len, int sum); | ||
38 | |||
39 | unsigned int | ||
40 | csum_partial_copy_from_user(const char __user *src, char *dst, int len, int sum, int *err_ptr); | ||
41 | |||
42 | /* | ||
43 | * This is the old (and unsafe) way of doing checksums, a warning message will | ||
44 | * be printed if it is used and an exception occurs. | ||
45 | * | ||
46 | * this functions should go away after some time. | ||
47 | */ | ||
48 | #define csum_partial_copy(src,dst,len,sum) csum_partial_copy_nocheck(src,dst,len,sum) | ||
49 | |||
50 | /* | ||
51 | * This is a version of ip_compute_csum() optimized for IP headers, | ||
52 | * which always checksum on 4 octet boundaries. | ||
53 | */ | ||
54 | static inline unsigned short | ||
55 | ip_fast_csum(unsigned char * iph, unsigned int ihl) | ||
56 | { | ||
57 | unsigned int sum, tmp1; | ||
58 | |||
59 | __asm__ __volatile__( | ||
60 | "ldr %0, [%1], #4 @ ip_fast_csum \n\ | ||
61 | ldr %3, [%1], #4 \n\ | ||
62 | sub %2, %2, #5 \n\ | ||
63 | adds %0, %0, %3 \n\ | ||
64 | ldr %3, [%1], #4 \n\ | ||
65 | adcs %0, %0, %3 \n\ | ||
66 | ldr %3, [%1], #4 \n\ | ||
67 | 1: adcs %0, %0, %3 \n\ | ||
68 | ldr %3, [%1], #4 \n\ | ||
69 | tst %2, #15 @ do this carefully \n\ | ||
70 | subne %2, %2, #1 @ without destroying \n\ | ||
71 | bne 1b @ the carry flag \n\ | ||
72 | adcs %0, %0, %3 \n\ | ||
73 | adc %0, %0, #0 \n\ | ||
74 | adds %0, %0, %0, lsl #16 \n\ | ||
75 | addcs %0, %0, #0x10000 \n\ | ||
76 | mvn %0, %0 \n\ | ||
77 | mov %0, %0, lsr #16" | ||
78 | : "=r" (sum), "=r" (iph), "=r" (ihl), "=r" (tmp1) | ||
79 | : "1" (iph), "2" (ihl) | ||
80 | : "cc"); | ||
81 | return sum; | ||
82 | } | ||
83 | |||
84 | /* | ||
85 | * Fold a partial checksum without adding pseudo headers | ||
86 | */ | ||
87 | static inline unsigned int | ||
88 | csum_fold(unsigned int sum) | ||
89 | { | ||
90 | __asm__( | ||
91 | "adds %0, %1, %1, lsl #16 @ csum_fold \n\ | ||
92 | addcs %0, %0, #0x10000" | ||
93 | : "=r" (sum) | ||
94 | : "r" (sum) | ||
95 | : "cc"); | ||
96 | return (~sum) >> 16; | ||
97 | } | ||
98 | |||
99 | static inline unsigned int | ||
100 | csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr, unsigned short len, | ||
101 | unsigned int proto, unsigned int sum) | ||
102 | { | ||
103 | __asm__( | ||
104 | "adds %0, %1, %2 @ csum_tcpudp_nofold \n\ | ||
105 | adcs %0, %0, %3 \n\ | ||
106 | adcs %0, %0, %4 \n\ | ||
107 | adcs %0, %0, %5 \n\ | ||
108 | adc %0, %0, #0" | ||
109 | : "=&r"(sum) | ||
110 | : "r" (sum), "r" (daddr), "r" (saddr), "r" (ntohs(len)), "Ir" (ntohs(proto)) | ||
111 | : "cc"); | ||
112 | return sum; | ||
113 | } | ||
114 | /* | ||
115 | * computes the checksum of the TCP/UDP pseudo-header | ||
116 | * returns a 16-bit checksum, already complemented | ||
117 | */ | ||
118 | static inline unsigned short int | ||
119 | csum_tcpudp_magic(unsigned long saddr, unsigned long daddr, unsigned short len, | ||
120 | unsigned int proto, unsigned int sum) | ||
121 | { | ||
122 | __asm__( | ||
123 | "adds %0, %1, %2 @ csum_tcpudp_magic \n\ | ||
124 | adcs %0, %0, %3 \n\ | ||
125 | adcs %0, %0, %4 \n\ | ||
126 | adcs %0, %0, %5 \n\ | ||
127 | adc %0, %0, #0 \n\ | ||
128 | adds %0, %0, %0, lsl #16 \n\ | ||
129 | addcs %0, %0, #0x10000 \n\ | ||
130 | mvn %0, %0" | ||
131 | : "=&r"(sum) | ||
132 | : "r" (sum), "r" (daddr), "r" (saddr), "r" (ntohs(len)), "Ir" (ntohs(proto)) | ||
133 | : "cc"); | ||
134 | return sum >> 16; | ||
135 | } | ||
136 | |||
137 | |||
138 | /* | ||
139 | * this routine is used for miscellaneous IP-like checksums, mainly | ||
140 | * in icmp.c | ||
141 | */ | ||
142 | static inline unsigned short | ||
143 | ip_compute_csum(unsigned char * buff, int len) | ||
144 | { | ||
145 | return csum_fold(csum_partial(buff, len, 0)); | ||
146 | } | ||
147 | |||
148 | #define _HAVE_ARCH_IPV6_CSUM | ||
149 | extern unsigned long | ||
150 | __csum_ipv6_magic(struct in6_addr *saddr, struct in6_addr *daddr, __u32 len, | ||
151 | __u32 proto, unsigned int sum); | ||
152 | |||
153 | static inline unsigned short int | ||
154 | csum_ipv6_magic(struct in6_addr *saddr, struct in6_addr *daddr, __u32 len, | ||
155 | unsigned short proto, unsigned int sum) | ||
156 | { | ||
157 | return csum_fold(__csum_ipv6_magic(saddr, daddr, htonl(len), | ||
158 | htonl(proto), sum)); | ||
159 | } | ||
160 | #endif | ||