1 /* $Id: checksum.h,v 1.16 2000/01/31 01:26:54 davem Exp $ */
2 #ifndef __SPARC64_CHECKSUM_H
3 #define __SPARC64_CHECKSUM_H
4
5 /* checksum.h: IP/UDP/TCP checksum routines on the V9.
6 *
7 * Copyright(C) 1995 Linus Torvalds
8 * Copyright(C) 1995 Miguel de Icaza
9 * Copyright(C) 1996 David S. Miller
10 * Copyright(C) 1996 Eddie C. Dost
11 * Copyright(C) 1997 Jakub Jelinek
12 *
13 * derived from:
14 * Alpha checksum c-code
15 * ix86 inline assembly
16 * RFC1071 Computing the Internet Checksum
17 */
18
19 #include <asm/uaccess.h>
20
21 /* computes the checksum of a memory block at buff, length len,
22 * and adds in "sum" (32-bit)
23 *
24 * returns a 32-bit number suitable for feeding into itself
25 * or csum_tcpudp_magic
26 *
27 * this function must be called with even lengths, except
28 * for the last fragment, which may be odd
29 *
30 * it's best to have buff aligned on a 32-bit boundary
31 */
32 extern unsigned int csum_partial(const unsigned char * buff, int len, unsigned int sum);
33
34 /* the same as csum_partial, but copies from user space while it
35 * checksums
36 *
37 * here even more important to align src and dst on a 32-bit (or even
38 * better 64-bit) boundary
39 */
40 extern unsigned int csum_partial_copy_sparc64(const char *src, char *dst, int len, unsigned int sum);
41
42 extern __inline__ unsigned int
43 csum_partial_copy_nocheck (const char *src, char *dst, int len,
44 unsigned int sum)
45 {
46 int ret;
47 unsigned char cur_ds = current->thread.current_ds.seg;
48 __asm__ __volatile__ ("wr %%g0, %0, %%asi" : : "i" (ASI_P));
49 ret = csum_partial_copy_sparc64(src, dst, len, sum);
50 __asm__ __volatile__ ("wr %%g0, %0, %%asi" : : "r" (cur_ds));
51 return ret;
52 }
53
54 extern __inline__ unsigned int
55 csum_partial_copy_from_user(const char *src, char *dst, int len,
56 unsigned int sum, int *err)
57 {
58 __asm__ __volatile__ ("stx %0, [%%sp + 0x7ff + 128]"
59 : : "r" (err));
60 return csum_partial_copy_sparc64(src, dst, len, sum);
61 }
62
63 /*
64 * Copy and checksum to user
65 */
66 #define HAVE_CSUM_COPY_USER
67 extern unsigned int csum_partial_copy_user_sparc64(const char *src, char *dst, int len, unsigned int sum);
68 extern __inline__ unsigned int
69 csum_and_copy_to_user(const char *src, char *dst, int len,
70 unsigned int sum, int *err)
71 {
72 __asm__ __volatile__ ("stx %0, [%%sp + 0x7ff + 128]"
73 : : "r" (err));
74 return csum_partial_copy_user_sparc64(src, dst, len, sum);
75 }
76
77 /* ihl is always 5 or greater, almost always is 5, and iph is word aligned
78 * the majority of the time.
79 */
80 extern __inline__ unsigned short ip_fast_csum(__const__ unsigned char *iph,
81 unsigned int ihl)
82 {
83 unsigned short sum;
84
85 /* Note: We must read %2 before we touch %0 for the first time,
86 * because GCC can legitimately use the same register for
87 * both operands.
88 */
89 __asm__ __volatile__("
90 sub %2, 4, %%g7 ! IEU0
91 lduw [%1 + 0x00], %0 ! Load Group
92 lduw [%1 + 0x04], %%g2 ! Load Group
93 lduw [%1 + 0x08], %%g3 ! Load Group
94 addcc %%g2, %0, %0 ! IEU1 1 Load Bubble + Group
95 lduw [%1 + 0x0c], %%g2 ! Load
96 addccc %%g3, %0, %0 ! Sngle Group no Bubble
97 lduw [%1 + 0x10], %%g3 ! Load Group
98 addccc %%g2, %0, %0 ! Sngle Group no Bubble
99 addc %0, %%g0, %0 ! Sngle Group
100 1: addcc %%g3, %0, %0 ! IEU1 Group no Bubble
101 add %1, 4, %1 ! IEU0
102 addccc %0, %%g0, %0 ! Sngle Group no Bubble
103 subcc %%g7, 1, %%g7 ! IEU1 Group
104 be,a,pt %%icc, 2f ! CTI
105 sll %0, 16, %%g2 ! IEU0
106 lduw [%1 + 0x10], %%g3 ! Load Group
107 ba,pt %%xcc, 1b ! CTI
108 nop ! IEU0
109 2: addcc %0, %%g2, %%g2 ! IEU1 Group
110 srl %%g2, 16, %0 ! IEU0 Group regdep XXX Scheisse!
111 addc %0, %%g0, %0 ! Sngle Group
112 xnor %%g0, %0, %0 ! IEU0 Group
113 srl %0, 0, %0 ! IEU0 Group XXX Scheisse!
114 " : "=r" (sum), "=&r" (iph)
115 : "r" (ihl), "1" (iph)
116 : "g2", "g3", "g7", "cc");
117 return sum;
118 }
119
120 /* Fold a partial checksum without adding pseudo headers. */
121 extern __inline__ unsigned short csum_fold(unsigned int sum)
122 {
123 unsigned int tmp;
124
125 __asm__ __volatile__("
126 addcc %0, %1, %1
127 srl %1, 16, %1
128 addc %1, %%g0, %1
129 xnor %%g0, %1, %0
130 " : "=&r" (sum), "=r" (tmp)
131 : "" (sum), "1" (sum<<16)
132 : "cc");
133 return (sum & 0xffff);
134 }
135
136 extern __inline__ unsigned long csum_tcpudp_nofold(unsigned long saddr,
137 unsigned long daddr,
138 unsigned int len,
139 unsigned short proto,
140 unsigned int sum)
141 {
142 __asm__ __volatile__("
143 addcc %1, %0, %0
144 addccc %2, %0, %0
145 addccc %3, %0, %0
146 addc %0, %%g0, %0
147 " : "=r" (sum), "=r" (saddr)
148 : "r" (daddr), "r" ((proto<<16)+len), "" (sum), "1" (saddr)
149 : "cc");
150 return sum;
151 }
152
153 /*
154 * computes the checksum of the TCP/UDP pseudo-header
155 * returns a 16-bit checksum, already complemented
156 */
157 static inline unsigned short int csum_tcpudp_magic(unsigned long saddr,
158 unsigned long daddr,
159 unsigned short len,
160 unsigned short proto,
161 unsigned int sum)
162 {
163 return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum));
164 }
165
166 #define _HAVE_ARCH_IPV6_CSUM
167
168 static __inline__ unsigned short int csum_ipv6_magic(struct in6_addr *saddr,
169 struct in6_addr *daddr,
170 __u32 len,
171 unsigned short proto,
172 unsigned int sum)
173 {
174 __asm__ __volatile__ ("
175 addcc %3, %4, %%g7
176 addccc %5, %%g7, %%g7
177 lduw [%2 + 0x0c], %%g2
178 lduw [%2 + 0x08], %%g3
179 addccc %%g2, %%g7, %%g7
180 lduw [%2 + 0x04], %%g2
181 addccc %%g3, %%g7, %%g7
182 lduw [%2 + 0x00], %%g3
183 addccc %%g2, %%g7, %%g7
184 lduw [%1 + 0x0c], %%g2
185 addccc %%g3, %%g7, %%g7
186 lduw [%1 + 0x08], %%g3
187 addccc %%g2, %%g7, %%g7
188 lduw [%1 + 0x04], %%g2
189 addccc %%g3, %%g7, %%g7
190 lduw [%1 + 0x00], %%g3
191 addccc %%g2, %%g7, %%g7
192 addccc %%g3, %%g7, %0
193 addc 0, %0, %0
194 " : "=&r" (sum)
195 : "r" (saddr), "r" (daddr), "r"(htonl(len)),
196 "r"(htonl(proto)), "r"(sum)
197 : "g2", "g3", "g7", "cc");
198
199 return csum_fold(sum);
200 }
201
202 /* this routine is used for miscellaneous IP-like checksums, mainly in icmp.c */
203 extern __inline__ unsigned short ip_compute_csum(unsigned char * buff, int len)
204 {
205 return csum_fold(csum_partial(buff, len, 0));
206 }
207
208 #endif /* !(__SPARC64_CHECKSUM_H) */
209
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