aboutsummaryrefslogtreecommitdiffstats
path: root/include/asm-mips/checksum.h
diff options
context:
space:
mode:
Diffstat (limited to 'include/asm-mips/checksum.h')
-rw-r--r--include/asm-mips/checksum.h253
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 */
31unsigned 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 */
37unsigned 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
44static 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 */
64unsigned 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 */
70static 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 */
94static 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
125static 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 */
169static 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 */
182static 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
188static __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 */
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-27 14:50:59 -0500