summaryrefslogtreecommitdiffstats
path: root/arch/sparc/include/asm/checksum_32.h
blob: 04471dc64847269e815a26752ef029cd9206c154 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
#ifndef __SPARC_CHECKSUM_H
#define __SPARC_CHECKSUM_H

/*  checksum.h:  IP/UDP/TCP checksum routines on the Sparc.
 *
 *  Copyright(C) 1995 Linus Torvalds
 *  Copyright(C) 1995 Miguel de Icaza
 *  Copyright(C) 1996 David S. Miller
 *  Copyright(C) 1996 Eddie C. Dost
 *  Copyright(C) 1997 Jakub Jelinek
 *
 * derived from:
 *	Alpha checksum c-code
 *      ix86 inline assembly
 *      RFC1071 Computing the Internet Checksum
 */

#include <linux/in6.h>
#include <asm/uaccess.h>

/* computes the checksum of a memory block at buff, length len,
 * and adds in "sum" (32-bit)
 *
 * returns a 32-bit number suitable for feeding into itself
 * or csum_tcpudp_magic
 *
 * this function must be called with even lengths, except
 * for the last fragment, which may be odd
 *
 * it's best to have buff aligned on a 32-bit boundary
 */
extern __wsum csum_partial(const void *buff, int len, __wsum sum);

/* the same as csum_partial, but copies from fs:src while it
 * checksums
 *
 * here even more important to align src and dst on a 32-bit (or even
 * better 64-bit) boundary
 */

extern unsigned int __csum_partial_copy_sparc_generic (const unsigned char *, unsigned char *);

static inline __wsum
csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum)
{
	register unsigned int ret asm("o0") = (unsigned int)src;
	register char *d asm("o1") = dst;
	register int l asm("g1") = len;

	__asm__ __volatile__ (
		"call __csum_partial_copy_sparc_generic\n\t"
		" mov %6, %%g7\n"
	: "=&r" (ret), "=&r" (d), "=&r" (l)
	: "0" (ret), "1" (d), "2" (l), "r" (sum)
	: "o2", "o3", "o4", "o5", "o7",
	  "g2", "g3", "g4", "g5", "g7",
	  "memory", "cc");
	return (__force __wsum)ret;
}

static inline __wsum
csum_partial_copy_from_user(const void __user *src, void *dst, int len,
			    __wsum sum, int *err)
  {
	register unsigned long ret asm("o0") = (unsigned long)src;
	register char *d asm("o1") = dst;
	register int l asm("g1") = len;
	register __wsum s asm("g7") = sum;

	__asm__ __volatile__ (
	".section __ex_table,#alloc\n\t"
	".align 4\n\t"
	".word 1f,2\n\t"
	".previous\n"
	"1:\n\t"
	"call __csum_partial_copy_sparc_generic\n\t"
	" st %8, [%%sp + 64]\n"
	: "=&r" (ret), "=&r" (d), "=&r" (l), "=&r" (s)
	: "0" (ret), "1" (d), "2" (l), "3" (s), "r" (err)
	: "o2", "o3", "o4", "o5", "o7", "g2", "g3", "g4", "g5",
	  "cc", "memory");
	return (__force __wsum)ret;
}

static inline __wsum
csum_partial_copy_to_user(const void *src, void __user *dst, int len,
			  __wsum sum, int *err)
{
	if (!access_ok (VERIFY_WRITE, dst, len)) {
		*err = -EFAULT;
		return sum;
	} else {
		register unsigned long ret asm("o0") = (unsigned long)src;
		register char __user *d asm("o1") = dst;
		register int l asm("g1") = len;
		register __wsum s asm("g7") = sum;

		__asm__ __volatile__ (
		".section __ex_table,#alloc\n\t"
		".align 4\n\t"
		".word 1f,1\n\t"
		".previous\n"
		"1:\n\t"
		"call __csum_partial_copy_sparc_generic\n\t"
		" st %8, [%%sp + 64]\n"
		: "=&r" (ret), "=&r" (d), "=&r" (l), "=&r" (s)
		: "0" (ret), "1" (d), "2" (l), "3" (s), "r" (err)
		: "o2", "o3", "o4", "o5", "o7",
		  "g2", "g3", "g4", "g5",
		  "cc", "memory");
		return (__force __wsum)ret;
	}
}

#define HAVE_CSUM_COPY_USER
#define csum_and_copy_to_user csum_partial_copy_to_user

/* ihl is always 5 or greater, almost always is 5, and iph is word aligned
 * the majority of the time.
 */
static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl)
{
	__sum16 sum;

	/* Note: We must read %2 before we touch %0 for the first time,
	 *       because GCC can legitimately use the same register for
	 *       both operands.
	 */
	__asm__ __volatile__("sub\t%2, 4, %%g4\n\t"
			     "ld\t[%1 + 0x00], %0\n\t"
			     "ld\t[%1 + 0x04], %%g2\n\t"
			     "ld\t[%1 + 0x08], %%g3\n\t"
			     "addcc\t%%g2, %0, %0\n\t"
			     "addxcc\t%%g3, %0, %0\n\t"
			     "ld\t[%1 + 0x0c], %%g2\n\t"
			     "ld\t[%1 + 0x10], %%g3\n\t"
			     "addxcc\t%%g2, %0, %0\n\t"
			     "addx\t%0, %%g0, %0\n"
			     "1:\taddcc\t%%g3, %0, %0\n\t"
			     "add\t%1, 4, %1\n\t"
			     "addxcc\t%0, %%g0, %0\n\t"
			     "subcc\t%%g4, 1, %%g4\n\t"
			     "be,a\t2f\n\t"
			     "sll\t%0, 16, %%g2\n\t"
			     "b\t1b\n\t"
			     "ld\t[%1 + 0x10], %%g3\n"
			     "2:\taddcc\t%0, %%g2, %%g2\n\t"
			     "srl\t%%g2, 16, %0\n\t"
			     "addx\t%0, %%g0, %0\n\t"
			     "xnor\t%%g0, %0, %0"
			     : "=r" (sum), "=&r" (iph)
			     : "r" (ihl), "1" (iph)
			     : "g2", "g3", "g4", "cc", "memory");
	return sum;
}

/* Fold a partial checksum without adding pseudo headers. */
static inline __sum16 csum_fold(__wsum sum)
{
	unsigned int tmp;

	__asm__ __volatile__("addcc\t%0, %1, %1\n\t"
			     "srl\t%1, 16, %1\n\t"
			     "addx\t%1, %%g0, %1\n\t"
			     "xnor\t%%g0, %1, %0"
			     : "=&r" (sum), "=r" (tmp)
			     : "0" (sum), "1" ((__force u32)sum<<16)
			     : "cc");
	return (__force __sum16)sum;
}

static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
					       unsigned short len,
					       unsigned short proto,
					       __wsum sum)
{
	__asm__ __volatile__("addcc\t%1, %0, %0\n\t"
			     "addxcc\t%2, %0, %0\n\t"
			     "addxcc\t%3, %0, %0\n\t"
			     "addx\t%0, %%g0, %0\n\t"
			     : "=r" (sum), "=r" (saddr)
			     : "r" (daddr), "r" (proto + len), "0" (sum),
			       "1" (saddr)
			     : "cc");
	return sum;
}

/*
 * computes the checksum of the TCP/UDP pseudo-header
 * returns a 16-bit checksum, already complemented
 */
static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
						   unsigned short len,
						   unsigned short proto,
						   __wsum sum)
{
	return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum));
}

#define _HAVE_ARCH_IPV6_CSUM

static inline __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
				      const struct in6_addr *daddr,
				      __u32 len, unsigned short proto,
				      __wsum sum)
{
	__asm__ __volatile__ (
		"addcc	%3, %4, %%g4\n\t"
		"addxcc	%5, %%g4, %%g4\n\t"
		"ld	[%2 + 0x0c], %%g2\n\t"
		"ld	[%2 + 0x08], %%g3\n\t"
		"addxcc	%%g2, %%g4, %%g4\n\t"
		"ld	[%2 + 0x04], %%g2\n\t"
		"addxcc	%%g3, %%g4, %%g4\n\t"
		"ld	[%2 + 0x00], %%g3\n\t"
		"addxcc	%%g2, %%g4, %%g4\n\t"
		"ld	[%1 + 0x0c], %%g2\n\t"
		"addxcc	%%g3, %%g4, %%g4\n\t"
		"ld	[%1 + 0x08], %%g3\n\t"
		"addxcc	%%g2, %%g4, %%g4\n\t"
		"ld	[%1 + 0x04], %%g2\n\t"
		"addxcc	%%g3, %%g4, %%g4\n\t"
		"ld	[%1 + 0x00], %%g3\n\t"
		"addxcc	%%g2, %%g4, %%g4\n\t"
		"addxcc	%%g3, %%g4, %0\n\t"
		"addx	0, %0, %0\n"
		: "=&r" (sum)
		: "r" (saddr), "r" (daddr),
		  "r"(htonl(len)), "r"(htonl(proto)), "r"(sum)
		: "g2", "g3", "g4", "cc");

	return csum_fold(sum);
}

/* this routine is used for miscellaneous IP-like checksums, mainly in icmp.c */
static inline __sum16 ip_compute_csum(const void *buff, int len)
{
	return csum_fold(csum_partial(buff, len, 0));
}

#define HAVE_ARCH_CSUM_ADD
static inline __wsum csum_add(__wsum csum, __wsum addend)
{
	__asm__ __volatile__(
		"addcc   %0, %1, %0\n"
		"addx    %0, %%g0, %0"
		: "=r" (csum)
		: "r" (addend), "0" (csum));

	return csum;
}

#endif /* !(__SPARC_CHECKSUM_H) */