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1da177e4 LT |
1 | #ifndef _X86_64_CHECKSUM_H |
2 | #define _X86_64_CHECKSUM_H | |
3 | ||
4 | /* | |
5 | * Checksums for x86-64 | |
6 | * Copyright 2002 by Andi Kleen, SuSE Labs | |
7 | * with some code from asm-i386/checksum.h | |
8 | */ | |
9 | ||
10 | #include <linux/compiler.h> | |
11 | #include <asm/uaccess.h> | |
12 | #include <asm/byteorder.h> | |
13 | ||
14 | /** | |
15 | * csum_fold - Fold and invert a 32bit checksum. | |
16 | * sum: 32bit unfolded sum | |
17 | * | |
18 | * Fold a 32bit running checksum to 16bit and invert it. This is usually | |
19 | * the last step before putting a checksum into a packet. | |
20 | * Make sure not to mix with 64bit checksums. | |
21 | */ | |
a4f89fb7 | 22 | static inline __sum16 csum_fold(__wsum sum) |
1da177e4 LT |
23 | { |
24 | __asm__( | |
25 | " addl %1,%0\n" | |
26 | " adcl $0xffff,%0" | |
27 | : "=r" (sum) | |
a4f89fb7 AV |
28 | : "r" ((__force u32)sum << 16), |
29 | "0" ((__force u32)sum & 0xffff0000) | |
1da177e4 | 30 | ); |
a4f89fb7 | 31 | return (__force __sum16)(~(__force u32)sum >> 16); |
1da177e4 LT |
32 | } |
33 | ||
34 | /* | |
35 | * This is a version of ip_compute_csum() optimized for IP headers, | |
36 | * which always checksum on 4 octet boundaries. | |
37 | * | |
38 | * By Jorge Cwik <jorge@laser.satlink.net>, adapted for linux by | |
39 | * Arnt Gulbrandsen. | |
40 | */ | |
41 | ||
42 | /** | |
43 | * ip_fast_csum - Compute the IPv4 header checksum efficiently. | |
44 | * iph: ipv4 header | |
45 | * ihl: length of header / 4 | |
46 | */ | |
a4f89fb7 | 47 | static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl) |
1da177e4 LT |
48 | { |
49 | unsigned int sum; | |
50 | ||
51 | asm( " movl (%1), %0\n" | |
52 | " subl $4, %2\n" | |
53 | " jbe 2f\n" | |
54 | " addl 4(%1), %0\n" | |
55 | " adcl 8(%1), %0\n" | |
56 | " adcl 12(%1), %0\n" | |
57 | "1: adcl 16(%1), %0\n" | |
58 | " lea 4(%1), %1\n" | |
59 | " decl %2\n" | |
60 | " jne 1b\n" | |
61 | " adcl $0, %0\n" | |
62 | " movl %0, %2\n" | |
63 | " shrl $16, %0\n" | |
64 | " addw %w2, %w0\n" | |
65 | " adcl $0, %0\n" | |
66 | " notl %0\n" | |
67 | "2:" | |
2c656491 | 68 | /* Since the input registers which are loaded with iph and ihl |
1da177e4 LT |
69 | are modified, we must also specify them as outputs, or gcc |
70 | will assume they contain their original values. */ | |
71 | : "=r" (sum), "=r" (iph), "=r" (ihl) | |
72 | : "1" (iph), "2" (ihl) | |
73 | : "memory"); | |
a4f89fb7 | 74 | return (__force __sum16)sum; |
1da177e4 LT |
75 | } |
76 | ||
77 | /** | |
78 | * csum_tcpup_nofold - Compute an IPv4 pseudo header checksum. | |
79 | * @saddr: source address | |
80 | * @daddr: destination address | |
81 | * @len: length of packet | |
82 | * @proto: ip protocol of packet | |
83 | * @sum: initial sum to be added in (32bit unfolded) | |
84 | * | |
85 | * Returns the pseudo header checksum the input data. Result is | |
86 | * 32bit unfolded. | |
87 | */ | |
a4f89fb7 AV |
88 | static inline __wsum |
89 | csum_tcpudp_nofold(__be32 saddr, __be32 daddr, unsigned short len, | |
90 | unsigned short proto, __wsum sum) | |
1da177e4 LT |
91 | { |
92 | asm(" addl %1, %0\n" | |
93 | " adcl %2, %0\n" | |
94 | " adcl %3, %0\n" | |
95 | " adcl $0, %0\n" | |
96 | : "=r" (sum) | |
a4f89fb7 AV |
97 | : "g" (daddr), "g" (saddr), |
98 | "g" ((len + proto)<<8), "0" (sum)); | |
1da177e4 LT |
99 | return sum; |
100 | } | |
101 | ||
102 | ||
103 | /** | |
104 | * csum_tcpup_magic - Compute an IPv4 pseudo header checksum. | |
105 | * @saddr: source address | |
106 | * @daddr: destination address | |
107 | * @len: length of packet | |
108 | * @proto: ip protocol of packet | |
109 | * @sum: initial sum to be added in (32bit unfolded) | |
110 | * | |
111 | * Returns the 16bit pseudo header checksum the input data already | |
112 | * complemented and ready to be filled in. | |
113 | */ | |
a4f89fb7 AV |
114 | static inline __sum16 |
115 | csum_tcpudp_magic(__be32 saddr, __be32 daddr, | |
116 | unsigned short len, unsigned short proto, __wsum sum) | |
1da177e4 LT |
117 | { |
118 | return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum)); | |
119 | } | |
120 | ||
121 | /** | |
122 | * csum_partial - Compute an internet checksum. | |
123 | * @buff: buffer to be checksummed | |
124 | * @len: length of buffer. | |
125 | * @sum: initial sum to be added in (32bit unfolded) | |
126 | * | |
127 | * Returns the 32bit unfolded internet checksum of the buffer. | |
128 | * Before filling it in it needs to be csum_fold()'ed. | |
129 | * buff should be aligned to a 64bit boundary if possible. | |
130 | */ | |
a4f89fb7 | 131 | extern __wsum csum_partial(const void *buff, int len, __wsum sum); |
1da177e4 LT |
132 | |
133 | #define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER 1 | |
134 | #define HAVE_CSUM_COPY_USER 1 | |
135 | ||
136 | ||
137 | /* Do not call this directly. Use the wrappers below */ | |
a4f89fb7 AV |
138 | extern __wsum csum_partial_copy_generic(const void *src, const void *dst, |
139 | int len, | |
140 | __wsum sum, | |
1da177e4 LT |
141 | int *src_err_ptr, int *dst_err_ptr); |
142 | ||
143 | ||
a4f89fb7 AV |
144 | extern __wsum csum_partial_copy_from_user(const void __user *src, void *dst, |
145 | int len, __wsum isum, int *errp); | |
146 | extern __wsum csum_partial_copy_to_user(const void *src, void __user *dst, | |
147 | int len, __wsum isum, int *errp); | |
148 | extern __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len, | |
149 | __wsum sum); | |
1da177e4 LT |
150 | |
151 | /* Old names. To be removed. */ | |
152 | #define csum_and_copy_to_user csum_partial_copy_to_user | |
153 | #define csum_and_copy_from_user csum_partial_copy_from_user | |
154 | ||
155 | /** | |
156 | * ip_compute_csum - Compute an 16bit IP checksum. | |
157 | * @buff: buffer address. | |
158 | * @len: length of buffer. | |
159 | * | |
160 | * Returns the 16bit folded/inverted checksum of the passed buffer. | |
161 | * Ready to fill in. | |
162 | */ | |
a4f89fb7 | 163 | extern __sum16 ip_compute_csum(const void *buff, int len); |
1da177e4 LT |
164 | |
165 | /** | |
166 | * csum_ipv6_magic - Compute checksum of an IPv6 pseudo header. | |
167 | * @saddr: source address | |
168 | * @daddr: destination address | |
169 | * @len: length of packet | |
170 | * @proto: protocol of packet | |
171 | * @sum: initial sum (32bit unfolded) to be added in | |
172 | * | |
173 | * Computes an IPv6 pseudo header checksum. This sum is added the checksum | |
174 | * into UDP/TCP packets and contains some link layer information. | |
175 | * Returns the unfolded 32bit checksum. | |
176 | */ | |
177 | ||
178 | struct in6_addr; | |
179 | ||
180 | #define _HAVE_ARCH_IPV6_CSUM 1 | |
a4f89fb7 AV |
181 | extern __sum16 |
182 | csum_ipv6_magic(const struct in6_addr *saddr, const struct in6_addr *daddr, | |
183 | __u32 len, unsigned short proto, __wsum sum); | |
1da177e4 LT |
184 | |
185 | static inline unsigned add32_with_carry(unsigned a, unsigned b) | |
186 | { | |
187 | asm("addl %2,%0\n\t" | |
188 | "adcl $0,%0" | |
189 | : "=r" (a) | |
190 | : "0" (a), "r" (b)); | |
191 | return a; | |
192 | } | |
193 | ||
194 | #endif | |
195 |