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-mips/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-mips/checksum.h')
-rw-r--r-- | include/asm-mips/checksum.h | 253 |
1 files changed, 253 insertions, 0 deletions
diff --git a/include/asm-mips/checksum.h b/include/asm-mips/checksum.h new file mode 100644 index 000000000000..c25cc92b9950 --- /dev/null +++ b/include/asm-mips/checksum.h | |||
@@ -0,0 +1,253 @@ | |||
1 | /* | ||
2 | * This file is subject to the terms and conditions of the GNU General Public | ||
3 | * License. See the file "COPYING" in the main directory of this archive | ||
4 | * for more details. | ||
5 | * | ||
6 | * Copyright (C) 1995, 96, 97, 98, 99, 2001 by Ralf Baechle | ||
7 | * Copyright (C) 1999 Silicon Graphics, Inc. | ||
8 | * Copyright (C) 2001 Thiemo Seufer. | ||
9 | * Copyright (C) 2002 Maciej W. Rozycki | ||
10 | */ | ||
11 | #ifndef _ASM_CHECKSUM_H | ||
12 | #define _ASM_CHECKSUM_H | ||
13 | |||
14 | #include <linux/config.h> | ||
15 | #include <linux/in6.h> | ||
16 | |||
17 | #include <asm/uaccess.h> | ||
18 | |||
19 | /* | ||
20 | * computes the checksum of a memory block at buff, length len, | ||
21 | * and adds in "sum" (32-bit) | ||
22 | * | ||
23 | * returns a 32-bit number suitable for feeding into itself | ||
24 | * or csum_tcpudp_magic | ||
25 | * | ||
26 | * this function must be called with even lengths, except | ||
27 | * for the last fragment, which may be odd | ||
28 | * | ||
29 | * it's best to have buff aligned on a 32-bit boundary | ||
30 | */ | ||
31 | unsigned int csum_partial(const unsigned char *buff, int len, unsigned int sum); | ||
32 | |||
33 | /* | ||
34 | * this is a new version of the above that records errors it finds in *errp, | ||
35 | * but continues and zeros the rest of the buffer. | ||
36 | */ | ||
37 | unsigned int csum_partial_copy_from_user(const unsigned char *src, unsigned char *dst, int len, | ||
38 | unsigned int sum, int *errp); | ||
39 | |||
40 | /* | ||
41 | * Copy and checksum to user | ||
42 | */ | ||
43 | #define HAVE_CSUM_COPY_USER | ||
44 | static inline unsigned int csum_and_copy_to_user (const unsigned char *src, | ||
45 | unsigned char __user *dst, | ||
46 | int len, int sum, | ||
47 | int *err_ptr) | ||
48 | { | ||
49 | might_sleep(); | ||
50 | sum = csum_partial(src, len, sum); | ||
51 | |||
52 | if (copy_to_user(dst, src, len)) { | ||
53 | *err_ptr = -EFAULT; | ||
54 | return -1; | ||
55 | } | ||
56 | |||
57 | return sum; | ||
58 | } | ||
59 | |||
60 | /* | ||
61 | * the same as csum_partial, but copies from user space (but on MIPS | ||
62 | * we have just one address space, so this is identical to the above) | ||
63 | */ | ||
64 | unsigned int csum_partial_copy_nocheck(const unsigned char *src, unsigned char *dst, | ||
65 | int len, unsigned int sum); | ||
66 | |||
67 | /* | ||
68 | * Fold a partial checksum without adding pseudo headers | ||
69 | */ | ||
70 | static inline unsigned short int csum_fold(unsigned int sum) | ||
71 | { | ||
72 | __asm__( | ||
73 | ".set\tnoat\t\t\t# csum_fold\n\t" | ||
74 | "sll\t$1,%0,16\n\t" | ||
75 | "addu\t%0,$1\n\t" | ||
76 | "sltu\t$1,%0,$1\n\t" | ||
77 | "srl\t%0,%0,16\n\t" | ||
78 | "addu\t%0,$1\n\t" | ||
79 | "xori\t%0,0xffff\n\t" | ||
80 | ".set\tat" | ||
81 | : "=r" (sum) | ||
82 | : "0" (sum)); | ||
83 | |||
84 | return sum; | ||
85 | } | ||
86 | |||
87 | /* | ||
88 | * This is a version of ip_compute_csum() optimized for IP headers, | ||
89 | * which always checksum on 4 octet boundaries. | ||
90 | * | ||
91 | * By Jorge Cwik <jorge@laser.satlink.net>, adapted for linux by | ||
92 | * Arnt Gulbrandsen. | ||
93 | */ | ||
94 | static inline unsigned short ip_fast_csum(unsigned char *iph, unsigned int ihl) | ||
95 | { | ||
96 | unsigned int *word = (unsigned int *) iph; | ||
97 | unsigned int *stop = word + ihl; | ||
98 | unsigned int csum; | ||
99 | int carry; | ||
100 | |||
101 | csum = word[0]; | ||
102 | csum += word[1]; | ||
103 | carry = (csum < word[1]); | ||
104 | csum += carry; | ||
105 | |||
106 | csum += word[2]; | ||
107 | carry = (csum < word[2]); | ||
108 | csum += carry; | ||
109 | |||
110 | csum += word[3]; | ||
111 | carry = (csum < word[3]); | ||
112 | csum += carry; | ||
113 | |||
114 | word += 4; | ||
115 | do { | ||
116 | csum += *word; | ||
117 | carry = (csum < *word); | ||
118 | csum += carry; | ||
119 | word++; | ||
120 | } while (word != stop); | ||
121 | |||
122 | return csum_fold(csum); | ||
123 | } | ||
124 | |||
125 | static inline unsigned int csum_tcpudp_nofold(unsigned long saddr, | ||
126 | unsigned long daddr, unsigned short len, unsigned short proto, | ||
127 | unsigned int sum) | ||
128 | { | ||
129 | __asm__( | ||
130 | ".set\tnoat\t\t\t# csum_tcpudp_nofold\n\t" | ||
131 | #ifdef CONFIG_MIPS32 | ||
132 | "addu\t%0, %2\n\t" | ||
133 | "sltu\t$1, %0, %2\n\t" | ||
134 | "addu\t%0, $1\n\t" | ||
135 | |||
136 | "addu\t%0, %3\n\t" | ||
137 | "sltu\t$1, %0, %3\n\t" | ||
138 | "addu\t%0, $1\n\t" | ||
139 | |||
140 | "addu\t%0, %4\n\t" | ||
141 | "sltu\t$1, %0, %4\n\t" | ||
142 | "addu\t%0, $1\n\t" | ||
143 | #endif | ||
144 | #ifdef CONFIG_MIPS64 | ||
145 | "daddu\t%0, %2\n\t" | ||
146 | "daddu\t%0, %3\n\t" | ||
147 | "daddu\t%0, %4\n\t" | ||
148 | "dsll32\t$1, %0, 0\n\t" | ||
149 | "daddu\t%0, $1\n\t" | ||
150 | "dsrl32\t%0, %0, 0\n\t" | ||
151 | #endif | ||
152 | ".set\tat" | ||
153 | : "=r" (sum) | ||
154 | : "0" (daddr), "r"(saddr), | ||
155 | #ifdef __MIPSEL__ | ||
156 | "r" (((unsigned long)htons(len)<<16) + proto*256), | ||
157 | #else | ||
158 | "r" (((unsigned long)(proto)<<16) + len), | ||
159 | #endif | ||
160 | "r" (sum)); | ||
161 | |||
162 | return sum; | ||
163 | } | ||
164 | |||
165 | /* | ||
166 | * computes the checksum of the TCP/UDP pseudo-header | ||
167 | * returns a 16-bit checksum, already complemented | ||
168 | */ | ||
169 | static inline unsigned short int csum_tcpudp_magic(unsigned long saddr, | ||
170 | unsigned long daddr, | ||
171 | unsigned short len, | ||
172 | unsigned short proto, | ||
173 | unsigned int sum) | ||
174 | { | ||
175 | return csum_fold(csum_tcpudp_nofold(saddr, daddr, len, proto, sum)); | ||
176 | } | ||
177 | |||
178 | /* | ||
179 | * this routine is used for miscellaneous IP-like checksums, mainly | ||
180 | * in icmp.c | ||
181 | */ | ||
182 | static inline unsigned short ip_compute_csum(unsigned char * buff, int len) | ||
183 | { | ||
184 | return csum_fold(csum_partial(buff, len, 0)); | ||
185 | } | ||
186 | |||
187 | #define _HAVE_ARCH_IPV6_CSUM | ||
188 | static __inline__ unsigned short int csum_ipv6_magic(struct in6_addr *saddr, | ||
189 | struct in6_addr *daddr, | ||
190 | __u32 len, | ||
191 | unsigned short proto, | ||
192 | unsigned int sum) | ||
193 | { | ||
194 | __asm__( | ||
195 | ".set\tpush\t\t\t# csum_ipv6_magic\n\t" | ||
196 | ".set\tnoreorder\n\t" | ||
197 | ".set\tnoat\n\t" | ||
198 | "addu\t%0, %5\t\t\t# proto (long in network byte order)\n\t" | ||
199 | "sltu\t$1, %0, %5\n\t" | ||
200 | "addu\t%0, $1\n\t" | ||
201 | |||
202 | "addu\t%0, %6\t\t\t# csum\n\t" | ||
203 | "sltu\t$1, %0, %6\n\t" | ||
204 | "lw\t%1, 0(%2)\t\t\t# four words source address\n\t" | ||
205 | "addu\t%0, $1\n\t" | ||
206 | "addu\t%0, %1\n\t" | ||
207 | "sltu\t$1, %0, %1\n\t" | ||
208 | |||
209 | "lw\t%1, 4(%2)\n\t" | ||
210 | "addu\t%0, $1\n\t" | ||
211 | "addu\t%0, %1\n\t" | ||
212 | "sltu\t$1, %0, %1\n\t" | ||
213 | |||
214 | "lw\t%1, 8(%2)\n\t" | ||
215 | "addu\t%0, $1\n\t" | ||
216 | "addu\t%0, %1\n\t" | ||
217 | "sltu\t$1, %0, %1\n\t" | ||
218 | |||
219 | "lw\t%1, 12(%2)\n\t" | ||
220 | "addu\t%0, $1\n\t" | ||
221 | "addu\t%0, %1\n\t" | ||
222 | "sltu\t$1, %0, %1\n\t" | ||
223 | |||
224 | "lw\t%1, 0(%3)\n\t" | ||
225 | "addu\t%0, $1\n\t" | ||
226 | "addu\t%0, %1\n\t" | ||
227 | "sltu\t$1, %0, %1\n\t" | ||
228 | |||
229 | "lw\t%1, 4(%3)\n\t" | ||
230 | "addu\t%0, $1\n\t" | ||
231 | "addu\t%0, %1\n\t" | ||
232 | "sltu\t$1, %0, %1\n\t" | ||
233 | |||
234 | "lw\t%1, 8(%3)\n\t" | ||
235 | "addu\t%0, $1\n\t" | ||
236 | "addu\t%0, %1\n\t" | ||
237 | "sltu\t$1, %0, %1\n\t" | ||
238 | |||
239 | "lw\t%1, 12(%3)\n\t" | ||
240 | "addu\t%0, $1\n\t" | ||
241 | "addu\t%0, %1\n\t" | ||
242 | "sltu\t$1, %0, %1\n\t" | ||
243 | |||
244 | "addu\t%0, $1\t\t\t# Add final carry\n\t" | ||
245 | ".set\tpop" | ||
246 | : "=r" (sum), "=r" (proto) | ||
247 | : "r" (saddr), "r" (daddr), | ||
248 | "0" (htonl(len)), "1" (htonl(proto)), "r" (sum)); | ||
249 | |||
250 | return csum_fold(sum); | ||
251 | } | ||
252 | |||
253 | #endif /* _ASM_CHECKSUM_H */ | ||