1 #ifdef __KERNEL__
2 #ifndef _ASM_M32R_CHECKSUM_H
3 #define _ASM_M32R_CHECKSUM_H
4
5 /*
6 * include/asm-m32r/checksum.h
7 *
8 * IP/TCP/UDP checksum routines
9 *
10 * This file is subject to the terms and conditions of the GNU General Public
11 * License. See the file "COPYING" in the main directory of this archive
12 * for more details.
13 *
14 * Some code taken from mips and parisc architecture.
15 *
16 * Copyright (C) 2001, 2002 Hiroyuki Kondo, Hirokazu Takata
17 * Copyright (C) 2004 Hirokazu Takata <takata at linux-m32r.org>
18 */
19
20 #include <linux/in6.h>
21
22 /*
23 * computes the checksum of a memory block at buff, length len,
24 * and adds in "sum" (32-bit)
25 *
26 * returns a 32-bit number suitable for feeding into itself
27 * or csum_tcpudp_magic
28 *
29 * this function must be called with even lengths, except
30 * for the last fragment, which may be odd
31 *
32 * it's best to have buff aligned on a 32-bit boundary
33 */
34 asmlinkage __wsum csum_partial(const void *buff, int len, __wsum sum);
35
36 /*
37 * The same as csum_partial, but copies from src while it checksums.
38 *
39 * Here even more important to align src and dst on a 32-bit (or even
40 * better 64-bit) boundary
41 */
42 extern __wsum csum_partial_copy_nocheck(const void *src, void *dst,
43 int len, __wsum sum);
44
45 /*
46 * This is a new version of the above that records errors it finds in *errp,
47 * but continues and zeros thre rest of the buffer.
48 */
49 extern __wsum csum_partial_copy_from_user(const void __user *src, void *dst,
50 int len, __wsum sum,
51 int *err_ptr);
52
53 /*
54 * Fold a partial checksum
55 */
56
csum_fold(__wsum sum)57 static inline __sum16 csum_fold(__wsum sum)
58 {
59 unsigned long tmpreg;
60 __asm__(
61 " sll3 %1, %0, #16 \n"
62 " cmp %0, %0 \n"
63 " addx %0, %1 \n"
64 " ldi %1, #0 \n"
65 " srli %0, #16 \n"
66 " addx %0, %1 \n"
67 " xor3 %0, %0, #0x0000ffff \n"
68 : "=r" (sum), "=&r" (tmpreg)
69 : "0" (sum)
70 : "cbit"
71 );
72 return (__force __sum16)sum;
73 }
74
75 /*
76 * This is a version of ip_compute_csum() optimized for IP headers,
77 * which always checksum on 4 octet boundaries.
78 */
ip_fast_csum(const void * iph,unsigned int ihl)79 static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl)
80 {
81 unsigned long tmpreg0, tmpreg1;
82 __wsum sum;
83
84 __asm__ __volatile__(
85 " ld %0, @%1+ \n"
86 " addi %2, #-4 \n"
87 "# bgez %2, 2f \n"
88 " cmp %0, %0 \n"
89 " ld %3, @%1+ \n"
90 " ld %4, @%1+ \n"
91 " addx %0, %3 \n"
92 " ld %3, @%1+ \n"
93 " addx %0, %4 \n"
94 " addx %0, %3 \n"
95 " .fillinsn\n"
96 "1: \n"
97 " ld %4, @%1+ \n"
98 " addi %2, #-1 \n"
99 " addx %0, %4 \n"
100 " bgtz %2, 1b \n"
101 "\n"
102 " ldi %3, #0 \n"
103 " addx %0, %3 \n"
104 " .fillinsn\n"
105 "2: \n"
106 /* Since the input registers which are loaded with iph and ihl
107 are modified, we must also specify them as outputs, or gcc
108 will assume they contain their original values. */
109 : "=&r" (sum), "=r" (iph), "=r" (ihl), "=&r" (tmpreg0), "=&r" (tmpreg1)
110 : "1" (iph), "2" (ihl)
111 : "cbit", "memory");
112
113 return csum_fold(sum);
114 }
115
csum_tcpudp_nofold(__be32 saddr,__be32 daddr,__u32 len,__u8 proto,__wsum sum)116 static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
117 __u32 len, __u8 proto,
118 __wsum sum)
119 {
120 #if defined(__LITTLE_ENDIAN)
121 unsigned long len_proto = (proto + len) << 8;
122 #else
123 unsigned long len_proto = proto + len;
124 #endif
125 unsigned long tmpreg;
126
127 __asm__(
128 " cmp %0, %0 \n"
129 " addx %0, %2 \n"
130 " addx %0, %3 \n"
131 " addx %0, %4 \n"
132 " ldi %1, #0 \n"
133 " addx %0, %1 \n"
134 : "=r" (sum), "=&r" (tmpreg)
135 : "r" (daddr), "r" (saddr), "r" (len_proto), "0" (sum)
136 : "cbit"
137 );
138
139 return sum;
140 }
141
142 /*
143 * computes the checksum of the TCP/UDP pseudo-header
144 * returns a 16-bit checksum, already complemented
145 */
csum_tcpudp_magic(__be32 saddr,__be32 daddr,__u32 len,__u8 proto,__wsum sum)146 static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
147 __u32 len, __u8 proto,
148 __wsum sum)
149 {
150 return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum));
151 }
152
153 /*
154 * this routine is used for miscellaneous IP-like checksums, mainly
155 * in icmp.c
156 */
157
ip_compute_csum(const void * buff,int len)158 static inline __sum16 ip_compute_csum(const void *buff, int len)
159 {
160 return csum_fold (csum_partial(buff, len, 0));
161 }
162
163 #define _HAVE_ARCH_IPV6_CSUM
csum_ipv6_magic(const struct in6_addr * saddr,const struct in6_addr * daddr,__u32 len,unsigned short proto,__wsum sum)164 static inline __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
165 const struct in6_addr *daddr,
166 __u32 len, unsigned short proto,
167 __wsum sum)
168 {
169 unsigned long tmpreg0, tmpreg1, tmpreg2, tmpreg3;
170 __asm__(
171 " ld %1, @(%5) \n"
172 " ld %2, @(4,%5) \n"
173 " ld %3, @(8,%5) \n"
174 " ld %4, @(12,%5) \n"
175 " add %0, %1 \n"
176 " addx %0, %2 \n"
177 " addx %0, %3 \n"
178 " addx %0, %4 \n"
179 " ld %1, @(%6) \n"
180 " ld %2, @(4,%6) \n"
181 " ld %3, @(8,%6) \n"
182 " ld %4, @(12,%6) \n"
183 " addx %0, %1 \n"
184 " addx %0, %2 \n"
185 " addx %0, %3 \n"
186 " addx %0, %4 \n"
187 " addx %0, %7 \n"
188 " addx %0, %8 \n"
189 " ldi %1, #0 \n"
190 " addx %0, %1 \n"
191 : "=&r" (sum), "=&r" (tmpreg0), "=&r" (tmpreg1),
192 "=&r" (tmpreg2), "=&r" (tmpreg3)
193 : "r" (saddr), "r" (daddr),
194 "r" (htonl(len)), "r" (htonl(proto)), "0" (sum)
195 : "cbit"
196 );
197
198 return csum_fold(sum);
199 }
200
201 #endif /* _ASM_M32R_CHECKSUM_H */
202 #endif /* __KERNEL__ */
203