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Linus Torvalds1da177e2005-04-16 15:20:36 -07001#ifndef _PARISC_CHECKSUM_H
2#define _PARISC_CHECKSUM_H
3
4#include <linux/in6.h>
5
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 */
Al Viro7814e4b2006-11-14 21:18:39 -080018extern __wsum csum_partial(const void *, int, __wsum);
Linus Torvalds1da177e2005-04-16 15:20:36 -070019
20/*
21 * The same as csum_partial, but copies from src while it checksums.
22 *
23 * Here even more important to align src and dst on a 32-bit (or even
24 * better 64-bit) boundary
25 */
Al Viro7814e4b2006-11-14 21:18:39 -080026extern __wsum csum_partial_copy_nocheck(const void *, void *, int, __wsum);
Linus Torvalds1da177e2005-04-16 15:20:36 -070027
28/*
29 * this is a new version of the above that records errors it finds in *errp,
30 * but continues and zeros the rest of the buffer.
31 */
Al Viro7814e4b2006-11-14 21:18:39 -080032extern __wsum csum_partial_copy_from_user(const void __user *src,
33 void *dst, int len, __wsum sum, int *errp);
Linus Torvalds1da177e2005-04-16 15:20:36 -070034
35/*
36 * Optimized for IP headers, which always checksum on 4 octet boundaries.
37 *
38 * Written by Randolph Chung <tausq@debian.org>, and then mucked with by
39 * LaMont Jones <lamont@debian.org>
40 */
Al Viro7814e4b2006-11-14 21:18:39 -080041static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl)
42{
Linus Torvalds1da177e2005-04-16 15:20:36 -070043 unsigned int sum;
44
Linus Torvalds1da177e2005-04-16 15:20:36 -070045 __asm__ __volatile__ (
46" ldws,ma 4(%1), %0\n"
47" addib,<= -4, %2, 2f\n"
48"\n"
49" ldws 4(%1), %%r20\n"
50" ldws 8(%1), %%r21\n"
51" add %0, %%r20, %0\n"
52" ldws,ma 12(%1), %%r19\n"
53" addc %0, %%r21, %0\n"
54" addc %0, %%r19, %0\n"
55"1: ldws,ma 4(%1), %%r19\n"
56" addib,< 0, %2, 1b\n"
57" addc %0, %%r19, %0\n"
58"\n"
59" extru %0, 31, 16, %%r20\n"
60" extru %0, 15, 16, %%r21\n"
61" addc %%r20, %%r21, %0\n"
62" extru %0, 15, 16, %%r21\n"
63" add %0, %%r21, %0\n"
64" subi -1, %0, %0\n"
65"2:\n"
66 : "=r" (sum), "=r" (iph), "=r" (ihl)
67 : "1" (iph), "2" (ihl)
68 : "r19", "r20", "r21" );
69
Al Viro7814e4b2006-11-14 21:18:39 -080070 return (__force __sum16)sum;
Linus Torvalds1da177e2005-04-16 15:20:36 -070071}
72
73/*
74 * Fold a partial checksum
75 */
Al Viro7814e4b2006-11-14 21:18:39 -080076static inline __sum16 csum_fold(__wsum csum)
Linus Torvalds1da177e2005-04-16 15:20:36 -070077{
Al Viro7814e4b2006-11-14 21:18:39 -080078 u32 sum = (__force u32)csum;
Linus Torvalds1da177e2005-04-16 15:20:36 -070079 /* add the swapped two 16-bit halves of sum,
80 a possible carry from adding the two 16-bit halves,
81 will carry from the lower half into the upper half,
82 giving us the correct sum in the upper half. */
83 sum += (sum << 16) + (sum >> 16);
Al Viro7814e4b2006-11-14 21:18:39 -080084 return (__force __sum16)(~sum >> 16);
Linus Torvalds1da177e2005-04-16 15:20:36 -070085}
86
Al Viro7814e4b2006-11-14 21:18:39 -080087static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
Linus Torvalds1da177e2005-04-16 15:20:36 -070088 unsigned short len,
89 unsigned short proto,
Al Viro7814e4b2006-11-14 21:18:39 -080090 __wsum sum)
Linus Torvalds1da177e2005-04-16 15:20:36 -070091{
92 __asm__(
93 " add %1, %0, %0\n"
94 " addc %2, %0, %0\n"
95 " addc %3, %0, %0\n"
96 " addc %%r0, %0, %0\n"
97 : "=r" (sum)
Al Viro7814e4b2006-11-14 21:18:39 -080098 : "r" (daddr), "r"(saddr), "r"(proto+len), "0"(sum));
99 return sum;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100}
101
102/*
103 * computes the checksum of the TCP/UDP pseudo-header
104 * returns a 16-bit checksum, already complemented
105 */
Al Viro7814e4b2006-11-14 21:18:39 -0800106static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107 unsigned short len,
108 unsigned short proto,
Al Viro7814e4b2006-11-14 21:18:39 -0800109 __wsum sum)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700110{
111 return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum));
112}
113
114/*
115 * this routine is used for miscellaneous IP-like checksums, mainly
116 * in icmp.c
117 */
Al Viro7814e4b2006-11-14 21:18:39 -0800118static inline __sum16 ip_compute_csum(const void *buf, int len)
119{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120 return csum_fold (csum_partial(buf, len, 0));
121}
122
123
124#define _HAVE_ARCH_IPV6_CSUM
Al Viro7814e4b2006-11-14 21:18:39 -0800125static __inline__ __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
126 const struct in6_addr *daddr,
127 __u32 len, unsigned short proto,
128 __wsum sum)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129{
130 __asm__ __volatile__ (
131
132#if BITS_PER_LONG > 32
133
134 /*
135 ** We can execute two loads and two adds per cycle on PA 8000.
136 ** But add insn's get serialized waiting for the carry bit.
137 ** Try to keep 4 registers with "live" values ahead of the ALU.
138 */
139
140" ldd,ma 8(%1), %%r19\n" /* get 1st saddr word */
141" ldd,ma 8(%2), %%r20\n" /* get 1st daddr word */
142" add %8, %3, %3\n"/* add 16-bit proto + len */
143" add %%r19, %0, %0\n"
144" ldd,ma 8(%1), %%r21\n" /* 2cd saddr */
145" ldd,ma 8(%2), %%r22\n" /* 2cd daddr */
146" add,dc %%r20, %0, %0\n"
147" add,dc %%r21, %0, %0\n"
148" add,dc %%r22, %0, %0\n"
149" add,dc %3, %0, %0\n" /* fold in proto+len | carry bit */
150" extrd,u %0, 31, 32, %%r19\n" /* copy upper half down */
151" depdi 0, 31, 32, %0\n" /* clear upper half */
152" add %%r19, %0, %0\n" /* fold into 32-bits */
153" addc 0, %0, %0\n" /* add carry */
154
155#else
156
157 /*
158 ** For PA 1.x, the insn order doesn't matter as much.
159 ** Insn stream is serialized on the carry bit here too.
160 ** result from the previous operation (eg r0 + x)
161 */
162
163" ldw,ma 4(%1), %%r19\n" /* get 1st saddr word */
164" ldw,ma 4(%2), %%r20\n" /* get 1st daddr word */
165" add %8, %3, %3\n" /* add 16-bit proto + len */
166" add %%r19, %0, %0\n"
167" ldw,ma 4(%1), %%r21\n" /* 2cd saddr */
168" addc %%r20, %0, %0\n"
169" ldw,ma 4(%2), %%r22\n" /* 2cd daddr */
170" addc %%r21, %0, %0\n"
171" ldw,ma 4(%1), %%r19\n" /* 3rd saddr */
172" addc %%r22, %0, %0\n"
173" ldw,ma 4(%2), %%r20\n" /* 3rd daddr */
174" addc %%r19, %0, %0\n"
175" ldw,ma 4(%1), %%r21\n" /* 4th saddr */
176" addc %%r20, %0, %0\n"
177" ldw,ma 4(%2), %%r22\n" /* 4th daddr */
178" addc %%r21, %0, %0\n"
179" addc %%r22, %0, %0\n"
180" addc %3, %0, %0\n" /* fold in proto+len, catch carry */
181
182#endif
183 : "=r" (sum), "=r" (saddr), "=r" (daddr), "=r" (len)
184 : "0" (sum), "1" (saddr), "2" (daddr), "3" (len), "r" (proto)
185 : "r19", "r20", "r21", "r22");
186 return csum_fold(sum);
187}
188
189/*
190 * Copy and checksum to user
191 */
192#define HAVE_CSUM_COPY_USER
Al Viro7814e4b2006-11-14 21:18:39 -0800193static __inline__ __wsum csum_and_copy_to_user(const void *src,
194 void __user *dst,
195 int len, __wsum sum,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700196 int *err_ptr)
197{
198 /* code stolen from include/asm-mips64 */
199 sum = csum_partial(src, len, sum);
200
201 if (copy_to_user(dst, src, len)) {
202 *err_ptr = -EFAULT;
Al Viro7814e4b2006-11-14 21:18:39 -0800203 return (__force __wsum)-1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204 }
205
206 return sum;
207}
208
209#endif
210