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-sh/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-sh/checksum.h')
-rw-r--r-- | include/asm-sh/checksum.h | 216 |
1 files changed, 216 insertions, 0 deletions
diff --git a/include/asm-sh/checksum.h b/include/asm-sh/checksum.h new file mode 100644 index 000000000000..5113c7f8a739 --- /dev/null +++ b/include/asm-sh/checksum.h | |||
@@ -0,0 +1,216 @@ | |||
1 | #ifndef __ASM_SH_CHECKSUM_H | ||
2 | #define __ASM_SH_CHECKSUM_H | ||
3 | |||
4 | /* | ||
5 | * This file is subject to the terms and conditions of the GNU General Public | ||
6 | * License. See the file "COPYING" in the main directory of this archive | ||
7 | * for more details. | ||
8 | * | ||
9 | * Copyright (C) 1999 by Kaz Kojima & Niibe Yutaka | ||
10 | */ | ||
11 | |||
12 | #include <linux/config.h> | ||
13 | #include <linux/in6.h> | ||
14 | |||
15 | /* | ||
16 | * computes the checksum of a memory block at buff, length len, | ||
17 | * and adds in "sum" (32-bit) | ||
18 | * | ||
19 | * returns a 32-bit number suitable for feeding into itself | ||
20 | * or csum_tcpudp_magic | ||
21 | * | ||
22 | * this function must be called with even lengths, except | ||
23 | * for the last fragment, which may be odd | ||
24 | * | ||
25 | * it's best to have buff aligned on a 32-bit boundary | ||
26 | */ | ||
27 | asmlinkage unsigned int csum_partial(const unsigned char * buff, int len, unsigned int sum); | ||
28 | |||
29 | /* | ||
30 | * the same as csum_partial, but copies from src while it | ||
31 | * checksums, and handles user-space pointer exceptions correctly, when needed. | ||
32 | * | ||
33 | * here even more important to align src and dst on a 32-bit (or even | ||
34 | * better 64-bit) boundary | ||
35 | */ | ||
36 | |||
37 | asmlinkage unsigned int csum_partial_copy_generic(const unsigned char *src, unsigned char *dst, | ||
38 | int len, int sum, int *src_err_ptr, int *dst_err_ptr); | ||
39 | |||
40 | /* | ||
41 | * Note: when you get a NULL pointer exception here this means someone | ||
42 | * passed in an incorrect kernel address to one of these functions. | ||
43 | * | ||
44 | * If you use these functions directly please don't forget the | ||
45 | * verify_area(). | ||
46 | */ | ||
47 | static __inline__ | ||
48 | unsigned int csum_partial_copy_nocheck (const unsigned char *src, unsigned char *dst, | ||
49 | int len, int sum) | ||
50 | { | ||
51 | return csum_partial_copy_generic ( src, dst, len, sum, NULL, NULL); | ||
52 | } | ||
53 | |||
54 | static __inline__ | ||
55 | unsigned int csum_partial_copy_from_user (const unsigned char *src, unsigned char *dst, | ||
56 | int len, int sum, int *err_ptr) | ||
57 | { | ||
58 | return csum_partial_copy_generic ( src, dst, len, sum, err_ptr, NULL); | ||
59 | } | ||
60 | |||
61 | /* | ||
62 | * Fold a partial checksum | ||
63 | */ | ||
64 | |||
65 | static __inline__ unsigned int csum_fold(unsigned int sum) | ||
66 | { | ||
67 | unsigned int __dummy; | ||
68 | __asm__("swap.w %0, %1\n\t" | ||
69 | "extu.w %0, %0\n\t" | ||
70 | "extu.w %1, %1\n\t" | ||
71 | "add %1, %0\n\t" | ||
72 | "swap.w %0, %1\n\t" | ||
73 | "add %1, %0\n\t" | ||
74 | "not %0, %0\n\t" | ||
75 | : "=r" (sum), "=&r" (__dummy) | ||
76 | : "0" (sum) | ||
77 | : "t"); | ||
78 | return sum; | ||
79 | } | ||
80 | |||
81 | /* | ||
82 | * This is a version of ip_compute_csum() optimized for IP headers, | ||
83 | * which always checksum on 4 octet boundaries. | ||
84 | * | ||
85 | * i386 version by Jorge Cwik <jorge@laser.satlink.net>, adapted | ||
86 | * for linux by * Arnt Gulbrandsen. | ||
87 | */ | ||
88 | static __inline__ unsigned short ip_fast_csum(unsigned char * iph, unsigned int ihl) | ||
89 | { | ||
90 | unsigned int sum, __dummy0, __dummy1; | ||
91 | |||
92 | __asm__ __volatile__( | ||
93 | "mov.l @%1+, %0\n\t" | ||
94 | "mov.l @%1+, %3\n\t" | ||
95 | "add #-2, %2\n\t" | ||
96 | "clrt\n\t" | ||
97 | "1:\t" | ||
98 | "addc %3, %0\n\t" | ||
99 | "movt %4\n\t" | ||
100 | "mov.l @%1+, %3\n\t" | ||
101 | "dt %2\n\t" | ||
102 | "bf/s 1b\n\t" | ||
103 | " cmp/eq #1, %4\n\t" | ||
104 | "addc %3, %0\n\t" | ||
105 | "addc %2, %0" /* Here %2 is 0, add carry-bit */ | ||
106 | /* Since the input registers which are loaded with iph and ihl | ||
107 | are modified, we must also specify them as outputs, or gcc | ||
108 | will assume they contain their original values. */ | ||
109 | : "=r" (sum), "=r" (iph), "=r" (ihl), "=&r" (__dummy0), "=&z" (__dummy1) | ||
110 | : "1" (iph), "2" (ihl) | ||
111 | : "t"); | ||
112 | |||
113 | return csum_fold(sum); | ||
114 | } | ||
115 | |||
116 | static __inline__ unsigned long csum_tcpudp_nofold(unsigned long saddr, | ||
117 | unsigned long daddr, | ||
118 | unsigned short len, | ||
119 | unsigned short proto, | ||
120 | unsigned int sum) | ||
121 | { | ||
122 | #ifdef __LITTLE_ENDIAN__ | ||
123 | unsigned long len_proto = (ntohs(len)<<16)+proto*256; | ||
124 | #else | ||
125 | unsigned long len_proto = (proto<<16)+len; | ||
126 | #endif | ||
127 | __asm__("clrt\n\t" | ||
128 | "addc %0, %1\n\t" | ||
129 | "addc %2, %1\n\t" | ||
130 | "addc %3, %1\n\t" | ||
131 | "movt %0\n\t" | ||
132 | "add %1, %0" | ||
133 | : "=r" (sum), "=r" (len_proto) | ||
134 | : "r" (daddr), "r" (saddr), "1" (len_proto), "0" (sum) | ||
135 | : "t"); | ||
136 | return sum; | ||
137 | } | ||
138 | |||
139 | /* | ||
140 | * computes the checksum of the TCP/UDP pseudo-header | ||
141 | * returns a 16-bit checksum, already complemented | ||
142 | */ | ||
143 | static __inline__ unsigned short int csum_tcpudp_magic(unsigned long saddr, | ||
144 | unsigned long daddr, | ||
145 | unsigned short len, | ||
146 | unsigned short proto, | ||
147 | unsigned int sum) | ||
148 | { | ||
149 | return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum)); | ||
150 | } | ||
151 | |||
152 | /* | ||
153 | * this routine is used for miscellaneous IP-like checksums, mainly | ||
154 | * in icmp.c | ||
155 | */ | ||
156 | |||
157 | static __inline__ unsigned short ip_compute_csum(unsigned char * buff, int len) | ||
158 | { | ||
159 | return csum_fold (csum_partial(buff, len, 0)); | ||
160 | } | ||
161 | |||
162 | #define _HAVE_ARCH_IPV6_CSUM | ||
163 | static __inline__ unsigned short int csum_ipv6_magic(struct in6_addr *saddr, | ||
164 | struct in6_addr *daddr, | ||
165 | __u32 len, | ||
166 | unsigned short proto, | ||
167 | unsigned int sum) | ||
168 | { | ||
169 | unsigned int __dummy; | ||
170 | __asm__("clrt\n\t" | ||
171 | "mov.l @(0,%2), %1\n\t" | ||
172 | "addc %1, %0\n\t" | ||
173 | "mov.l @(4,%2), %1\n\t" | ||
174 | "addc %1, %0\n\t" | ||
175 | "mov.l @(8,%2), %1\n\t" | ||
176 | "addc %1, %0\n\t" | ||
177 | "mov.l @(12,%2), %1\n\t" | ||
178 | "addc %1, %0\n\t" | ||
179 | "mov.l @(0,%3), %1\n\t" | ||
180 | "addc %1, %0\n\t" | ||
181 | "mov.l @(4,%3), %1\n\t" | ||
182 | "addc %1, %0\n\t" | ||
183 | "mov.l @(8,%3), %1\n\t" | ||
184 | "addc %1, %0\n\t" | ||
185 | "mov.l @(12,%3), %1\n\t" | ||
186 | "addc %1, %0\n\t" | ||
187 | "addc %4, %0\n\t" | ||
188 | "addc %5, %0\n\t" | ||
189 | "movt %1\n\t" | ||
190 | "add %1, %0\n" | ||
191 | : "=r" (sum), "=&r" (__dummy) | ||
192 | : "r" (saddr), "r" (daddr), | ||
193 | "r" (htonl(len)), "r" (htonl(proto)), "0" (sum) | ||
194 | : "t"); | ||
195 | |||
196 | return csum_fold(sum); | ||
197 | } | ||
198 | |||
199 | /* | ||
200 | * Copy and checksum to user | ||
201 | */ | ||
202 | #define HAVE_CSUM_COPY_USER | ||
203 | static __inline__ unsigned int csum_and_copy_to_user (const unsigned char *src, | ||
204 | unsigned char __user *dst, | ||
205 | int len, int sum, | ||
206 | int *err_ptr) | ||
207 | { | ||
208 | if (access_ok(VERIFY_WRITE, dst, len)) | ||
209 | return csum_partial_copy_generic(src, dst, len, sum, NULL, err_ptr); | ||
210 | |||
211 | if (len) | ||
212 | *err_ptr = -EFAULT; | ||
213 | |||
214 | return -1; /* invalid checksum */ | ||
215 | } | ||
216 | #endif /* __ASM_SH_CHECKSUM_H */ | ||