1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __SPARC_CHECKSUM_H
3 #define __SPARC_CHECKSUM_H
4
5 /* checksum.h: IP/UDP/TCP checksum routines on the Sparc.
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 <linux/in6.h>
20 #include <linux/uaccess.h>
21
22 /* computes the checksum of a memory block at buff, length len,
23 * and adds in "sum" (32-bit)
24 *
25 * returns a 32-bit number suitable for feeding into itself
26 * or csum_tcpudp_magic
27 *
28 * this function must be called with even lengths, except
29 * for the last fragment, which may be odd
30 *
31 * it's best to have buff aligned on a 32-bit boundary
32 */
33 __wsum csum_partial(const void *buff, int len, __wsum sum);
34
35 /* the same as csum_partial, but copies from fs:src while it
36 * checksums
37 *
38 * here even more important to align src and dst on a 32-bit (or even
39 * better 64-bit) boundary
40 */
41
42 unsigned int __csum_partial_copy_sparc_generic (const unsigned char *, unsigned char *);
43
44 static inline __wsum
csum_partial_copy_nocheck(const void * src,void * dst,int len,__wsum sum)45 csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum)
46 {
47 register unsigned int ret asm("o0") = (unsigned int)src;
48 register char *d asm("o1") = dst;
49 register int l asm("g1") = len;
50
51 __asm__ __volatile__ (
52 "call __csum_partial_copy_sparc_generic\n\t"
53 " mov %6, %%g7\n"
54 : "=&r" (ret), "=&r" (d), "=&r" (l)
55 : "0" (ret), "1" (d), "2" (l), "r" (sum)
56 : "o2", "o3", "o4", "o5", "o7",
57 "g2", "g3", "g4", "g5", "g7",
58 "memory", "cc");
59 return (__force __wsum)ret;
60 }
61
62 static inline __wsum
csum_partial_copy_from_user(const void __user * src,void * dst,int len,__wsum sum,int * err)63 csum_partial_copy_from_user(const void __user *src, void *dst, int len,
64 __wsum sum, int *err)
65 {
66 register unsigned long ret asm("o0") = (unsigned long)src;
67 register char *d asm("o1") = dst;
68 register int l asm("g1") = len;
69 register __wsum s asm("g7") = sum;
70
71 __asm__ __volatile__ (
72 ".section __ex_table,#alloc\n\t"
73 ".align 4\n\t"
74 ".word 1f,2\n\t"
75 ".previous\n"
76 "1:\n\t"
77 "call __csum_partial_copy_sparc_generic\n\t"
78 " st %8, [%%sp + 64]\n"
79 : "=&r" (ret), "=&r" (d), "=&r" (l), "=&r" (s)
80 : "0" (ret), "1" (d), "2" (l), "3" (s), "r" (err)
81 : "o2", "o3", "o4", "o5", "o7", "g2", "g3", "g4", "g5",
82 "cc", "memory");
83 return (__force __wsum)ret;
84 }
85
86 static inline __wsum
csum_partial_copy_to_user(const void * src,void __user * dst,int len,__wsum sum,int * err)87 csum_partial_copy_to_user(const void *src, void __user *dst, int len,
88 __wsum sum, int *err)
89 {
90 if (!access_ok(dst, len)) {
91 *err = -EFAULT;
92 return sum;
93 } else {
94 register unsigned long ret asm("o0") = (unsigned long)src;
95 register char __user *d asm("o1") = dst;
96 register int l asm("g1") = len;
97 register __wsum s asm("g7") = sum;
98
99 __asm__ __volatile__ (
100 ".section __ex_table,#alloc\n\t"
101 ".align 4\n\t"
102 ".word 1f,1\n\t"
103 ".previous\n"
104 "1:\n\t"
105 "call __csum_partial_copy_sparc_generic\n\t"
106 " st %8, [%%sp + 64]\n"
107 : "=&r" (ret), "=&r" (d), "=&r" (l), "=&r" (s)
108 : "0" (ret), "1" (d), "2" (l), "3" (s), "r" (err)
109 : "o2", "o3", "o4", "o5", "o7",
110 "g2", "g3", "g4", "g5",
111 "cc", "memory");
112 return (__force __wsum)ret;
113 }
114 }
115
116 #define HAVE_CSUM_COPY_USER
117 #define csum_and_copy_to_user csum_partial_copy_to_user
118
119 /* ihl is always 5 or greater, almost always is 5, and iph is word aligned
120 * the majority of the time.
121 */
ip_fast_csum(const void * iph,unsigned int ihl)122 static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl)
123 {
124 __sum16 sum;
125
126 /* Note: We must read %2 before we touch %0 for the first time,
127 * because GCC can legitimately use the same register for
128 * both operands.
129 */
130 __asm__ __volatile__("sub\t%2, 4, %%g4\n\t"
131 "ld\t[%1 + 0x00], %0\n\t"
132 "ld\t[%1 + 0x04], %%g2\n\t"
133 "ld\t[%1 + 0x08], %%g3\n\t"
134 "addcc\t%%g2, %0, %0\n\t"
135 "addxcc\t%%g3, %0, %0\n\t"
136 "ld\t[%1 + 0x0c], %%g2\n\t"
137 "ld\t[%1 + 0x10], %%g3\n\t"
138 "addxcc\t%%g2, %0, %0\n\t"
139 "addx\t%0, %%g0, %0\n"
140 "1:\taddcc\t%%g3, %0, %0\n\t"
141 "add\t%1, 4, %1\n\t"
142 "addxcc\t%0, %%g0, %0\n\t"
143 "subcc\t%%g4, 1, %%g4\n\t"
144 "be,a\t2f\n\t"
145 "sll\t%0, 16, %%g2\n\t"
146 "b\t1b\n\t"
147 "ld\t[%1 + 0x10], %%g3\n"
148 "2:\taddcc\t%0, %%g2, %%g2\n\t"
149 "srl\t%%g2, 16, %0\n\t"
150 "addx\t%0, %%g0, %0\n\t"
151 "xnor\t%%g0, %0, %0"
152 : "=r" (sum), "=&r" (iph)
153 : "r" (ihl), "1" (iph)
154 : "g2", "g3", "g4", "cc", "memory");
155 return sum;
156 }
157
158 /* Fold a partial checksum without adding pseudo headers. */
csum_fold(__wsum sum)159 static inline __sum16 csum_fold(__wsum sum)
160 {
161 unsigned int tmp;
162
163 __asm__ __volatile__("addcc\t%0, %1, %1\n\t"
164 "srl\t%1, 16, %1\n\t"
165 "addx\t%1, %%g0, %1\n\t"
166 "xnor\t%%g0, %1, %0"
167 : "=&r" (sum), "=r" (tmp)
168 : "0" (sum), "1" ((__force u32)sum<<16)
169 : "cc");
170 return (__force __sum16)sum;
171 }
172
csum_tcpudp_nofold(__be32 saddr,__be32 daddr,__u32 len,__u8 proto,__wsum sum)173 static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
174 __u32 len, __u8 proto,
175 __wsum sum)
176 {
177 __asm__ __volatile__("addcc\t%1, %0, %0\n\t"
178 "addxcc\t%2, %0, %0\n\t"
179 "addxcc\t%3, %0, %0\n\t"
180 "addx\t%0, %%g0, %0\n\t"
181 : "=r" (sum), "=r" (saddr)
182 : "r" (daddr), "r" (proto + len), "0" (sum),
183 "1" (saddr)
184 : "cc");
185 return sum;
186 }
187
188 /*
189 * computes the checksum of the TCP/UDP pseudo-header
190 * returns a 16-bit checksum, already complemented
191 */
csum_tcpudp_magic(__be32 saddr,__be32 daddr,__u32 len,__u8 proto,__wsum sum)192 static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
193 __u32 len, __u8 proto,
194 __wsum sum)
195 {
196 return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum));
197 }
198
199 #define _HAVE_ARCH_IPV6_CSUM
200
csum_ipv6_magic(const struct in6_addr * saddr,const struct in6_addr * daddr,__u32 len,__u8 proto,__wsum sum)201 static inline __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
202 const struct in6_addr *daddr,
203 __u32 len, __u8 proto, __wsum sum)
204 {
205 __asm__ __volatile__ (
206 "addcc %3, %4, %%g4\n\t"
207 "addxcc %5, %%g4, %%g4\n\t"
208 "ld [%2 + 0x0c], %%g2\n\t"
209 "ld [%2 + 0x08], %%g3\n\t"
210 "addxcc %%g2, %%g4, %%g4\n\t"
211 "ld [%2 + 0x04], %%g2\n\t"
212 "addxcc %%g3, %%g4, %%g4\n\t"
213 "ld [%2 + 0x00], %%g3\n\t"
214 "addxcc %%g2, %%g4, %%g4\n\t"
215 "ld [%1 + 0x0c], %%g2\n\t"
216 "addxcc %%g3, %%g4, %%g4\n\t"
217 "ld [%1 + 0x08], %%g3\n\t"
218 "addxcc %%g2, %%g4, %%g4\n\t"
219 "ld [%1 + 0x04], %%g2\n\t"
220 "addxcc %%g3, %%g4, %%g4\n\t"
221 "ld [%1 + 0x00], %%g3\n\t"
222 "addxcc %%g2, %%g4, %%g4\n\t"
223 "addxcc %%g3, %%g4, %0\n\t"
224 "addx 0, %0, %0\n"
225 : "=&r" (sum)
226 : "r" (saddr), "r" (daddr),
227 "r"(htonl(len)), "r"(htonl(proto)), "r"(sum)
228 : "g2", "g3", "g4", "cc");
229
230 return csum_fold(sum);
231 }
232
233 /* this routine is used for miscellaneous IP-like checksums, mainly in icmp.c */
ip_compute_csum(const void * buff,int len)234 static inline __sum16 ip_compute_csum(const void *buff, int len)
235 {
236 return csum_fold(csum_partial(buff, len, 0));
237 }
238
239 #define HAVE_ARCH_CSUM_ADD
csum_add(__wsum csum,__wsum addend)240 static inline __wsum csum_add(__wsum csum, __wsum addend)
241 {
242 __asm__ __volatile__(
243 "addcc %0, %1, %0\n"
244 "addx %0, %%g0, %0"
245 : "=r" (csum)
246 : "r" (addend), "0" (csum));
247
248 return csum;
249 }
250
251 #endif /* !(__SPARC_CHECKSUM_H) */
252