1 #ifndef _M68K_CHECKSUM_H
2 #define _M68K_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 */
18 __wsum csum_partial(const void *buff, int len, __wsum sum);
19
20 /*
21 * the same as csum_partial, but copies from src while it
22 * checksums
23 *
24 * here even more important to align src and dst on a 32-bit (or even
25 * better 64-bit) boundary
26 */
27
28 extern __wsum csum_partial_copy_from_user(const void __user *src,
29 void *dst,
30 int len, __wsum sum,
31 int *csum_err);
32
33 extern __wsum csum_partial_copy_nocheck(const void *src,
34 void *dst, int len,
35 __wsum sum);
36
37 /*
38 * This is a version of ip_compute_csum() optimized for IP headers,
39 * which always checksum on 4 octet boundaries.
40 *
41 */
ip_fast_csum(const void * iph,unsigned int ihl)42 static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl)
43 {
44 unsigned int sum = 0;
45 unsigned long tmp;
46
47 __asm__ ("subqw #1,%2\n"
48 "1:\t"
49 "movel %1@+,%3\n\t"
50 "addxl %3,%0\n\t"
51 "dbra %2,1b\n\t"
52 "movel %0,%3\n\t"
53 "swap %3\n\t"
54 "addxw %3,%0\n\t"
55 "clrw %3\n\t"
56 "addxw %3,%0\n\t"
57 : "=d" (sum), "=&a" (iph), "=&d" (ihl), "=&d" (tmp)
58 : "0" (sum), "1" (iph), "2" (ihl)
59 : "memory");
60 return (__force __sum16)~sum;
61 }
62
63 /*
64 * Fold a partial checksum
65 */
66
csum_fold(__wsum sum)67 static inline __sum16 csum_fold(__wsum sum)
68 {
69 unsigned int tmp = (__force u32)sum;
70 __asm__("swap %1\n\t"
71 "addw %1, %0\n\t"
72 "clrw %1\n\t"
73 "addxw %1, %0"
74 : "=&d" (sum), "=&d" (tmp)
75 : "0" (sum), "1" (tmp));
76 return (__force __sum16)~sum;
77 }
78
79
80 static inline __wsum
csum_tcpudp_nofold(__be32 saddr,__be32 daddr,unsigned short len,unsigned short proto,__wsum sum)81 csum_tcpudp_nofold(__be32 saddr, __be32 daddr, unsigned short len,
82 unsigned short proto, __wsum sum)
83 {
84 __asm__ ("addl %2,%0\n\t"
85 "addxl %3,%0\n\t"
86 "addxl %4,%0\n\t"
87 "clrl %1\n\t"
88 "addxl %1,%0"
89 : "=&d" (sum), "=d" (saddr)
90 : "g" (daddr), "1" (saddr), "d" (len + proto),
91 "0" (sum));
92 return sum;
93 }
94
95
96 /*
97 * computes the checksum of the TCP/UDP pseudo-header
98 * returns a 16-bit checksum, already complemented
99 */
100 static inline __sum16
csum_tcpudp_magic(__be32 saddr,__be32 daddr,unsigned short len,unsigned short proto,__wsum sum)101 csum_tcpudp_magic(__be32 saddr, __be32 daddr, unsigned short len,
102 unsigned short proto, __wsum sum)
103 {
104 return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum));
105 }
106
107 /*
108 * this routine is used for miscellaneous IP-like checksums, mainly
109 * in icmp.c
110 */
111
ip_compute_csum(const void * buff,int len)112 static inline __sum16 ip_compute_csum(const void *buff, int len)
113 {
114 return csum_fold (csum_partial(buff, len, 0));
115 }
116
117 #define _HAVE_ARCH_IPV6_CSUM
118 static __inline__ __sum16
csum_ipv6_magic(const struct in6_addr * saddr,const struct in6_addr * daddr,__u32 len,unsigned short proto,__wsum sum)119 csum_ipv6_magic(const struct in6_addr *saddr, const struct in6_addr *daddr,
120 __u32 len, unsigned short proto, __wsum sum)
121 {
122 register unsigned long tmp;
123 __asm__("addl %2@,%0\n\t"
124 "movel %2@(4),%1\n\t"
125 "addxl %1,%0\n\t"
126 "movel %2@(8),%1\n\t"
127 "addxl %1,%0\n\t"
128 "movel %2@(12),%1\n\t"
129 "addxl %1,%0\n\t"
130 "movel %3@,%1\n\t"
131 "addxl %1,%0\n\t"
132 "movel %3@(4),%1\n\t"
133 "addxl %1,%0\n\t"
134 "movel %3@(8),%1\n\t"
135 "addxl %1,%0\n\t"
136 "movel %3@(12),%1\n\t"
137 "addxl %1,%0\n\t"
138 "addxl %4,%0\n\t"
139 "clrl %1\n\t"
140 "addxl %1,%0"
141 : "=&d" (sum), "=&d" (tmp)
142 : "a" (saddr), "a" (daddr), "d" (len + proto),
143 "0" (sum));
144
145 return csum_fold(sum);
146 }
147
148 #endif /* _M68K_CHECKSUM_H */
149