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Diffstat (limited to 'arch/x86/include/asm/checksum_64.h')
-rw-r--r-- | arch/x86/include/asm/checksum_64.h | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/arch/x86/include/asm/checksum_64.h b/arch/x86/include/asm/checksum_64.h new file mode 100644 index 000000000000..110f403beb89 --- /dev/null +++ b/arch/x86/include/asm/checksum_64.h | |||
@@ -0,0 +1,191 @@ | |||
1 | #ifndef ASM_X86__CHECKSUM_64_H | ||
2 | #define ASM_X86__CHECKSUM_64_H | ||
3 | |||
4 | /* | ||
5 | * Checksums for x86-64 | ||
6 | * Copyright 2002 by Andi Kleen, SuSE Labs | ||
7 | * with some code from asm-x86/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 | */ | ||
22 | static inline __sum16 csum_fold(__wsum sum) | ||
23 | { | ||
24 | asm(" addl %1,%0\n" | ||
25 | " adcl $0xffff,%0" | ||
26 | : "=r" (sum) | ||
27 | : "r" ((__force u32)sum << 16), | ||
28 | "0" ((__force u32)sum & 0xffff0000)); | ||
29 | return (__force __sum16)(~(__force u32)sum >> 16); | ||
30 | } | ||
31 | |||
32 | /* | ||
33 | * This is a version of ip_compute_csum() optimized for IP headers, | ||
34 | * which always checksum on 4 octet boundaries. | ||
35 | * | ||
36 | * By Jorge Cwik <jorge@laser.satlink.net>, adapted for linux by | ||
37 | * Arnt Gulbrandsen. | ||
38 | */ | ||
39 | |||
40 | /** | ||
41 | * ip_fast_csum - Compute the IPv4 header checksum efficiently. | ||
42 | * iph: ipv4 header | ||
43 | * ihl: length of header / 4 | ||
44 | */ | ||
45 | static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl) | ||
46 | { | ||
47 | unsigned int sum; | ||
48 | |||
49 | asm(" movl (%1), %0\n" | ||
50 | " subl $4, %2\n" | ||
51 | " jbe 2f\n" | ||
52 | " addl 4(%1), %0\n" | ||
53 | " adcl 8(%1), %0\n" | ||
54 | " adcl 12(%1), %0\n" | ||
55 | "1: adcl 16(%1), %0\n" | ||
56 | " lea 4(%1), %1\n" | ||
57 | " decl %2\n" | ||
58 | " jne 1b\n" | ||
59 | " adcl $0, %0\n" | ||
60 | " movl %0, %2\n" | ||
61 | " shrl $16, %0\n" | ||
62 | " addw %w2, %w0\n" | ||
63 | " adcl $0, %0\n" | ||
64 | " notl %0\n" | ||
65 | "2:" | ||
66 | /* Since the input registers which are loaded with iph and ihl | ||
67 | are modified, we must also specify them as outputs, or gcc | ||
68 | will assume they contain their original values. */ | ||
69 | : "=r" (sum), "=r" (iph), "=r" (ihl) | ||
70 | : "1" (iph), "2" (ihl) | ||
71 | : "memory"); | ||
72 | return (__force __sum16)sum; | ||
73 | } | ||
74 | |||
75 | /** | ||
76 | * csum_tcpup_nofold - Compute an IPv4 pseudo header checksum. | ||
77 | * @saddr: source address | ||
78 | * @daddr: destination address | ||
79 | * @len: length of packet | ||
80 | * @proto: ip protocol of packet | ||
81 | * @sum: initial sum to be added in (32bit unfolded) | ||
82 | * | ||
83 | * Returns the pseudo header checksum the input data. Result is | ||
84 | * 32bit unfolded. | ||
85 | */ | ||
86 | static inline __wsum | ||
87 | csum_tcpudp_nofold(__be32 saddr, __be32 daddr, unsigned short len, | ||
88 | unsigned short proto, __wsum sum) | ||
89 | { | ||
90 | asm(" addl %1, %0\n" | ||
91 | " adcl %2, %0\n" | ||
92 | " adcl %3, %0\n" | ||
93 | " adcl $0, %0\n" | ||
94 | : "=r" (sum) | ||
95 | : "g" (daddr), "g" (saddr), | ||
96 | "g" ((len + proto)<<8), "0" (sum)); | ||
97 | return sum; | ||
98 | } | ||
99 | |||
100 | |||
101 | /** | ||
102 | * csum_tcpup_magic - Compute an IPv4 pseudo header checksum. | ||
103 | * @saddr: source address | ||
104 | * @daddr: destination address | ||
105 | * @len: length of packet | ||
106 | * @proto: ip protocol of packet | ||
107 | * @sum: initial sum to be added in (32bit unfolded) | ||
108 | * | ||
109 | * Returns the 16bit pseudo header checksum the input data already | ||
110 | * complemented and ready to be filled in. | ||
111 | */ | ||
112 | static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr, | ||
113 | unsigned short len, | ||
114 | unsigned short proto, __wsum sum) | ||
115 | { | ||
116 | return csum_fold(csum_tcpudp_nofold(saddr, daddr, len, proto, sum)); | ||
117 | } | ||
118 | |||
119 | /** | ||
120 | * csum_partial - Compute an internet checksum. | ||
121 | * @buff: buffer to be checksummed | ||
122 | * @len: length of buffer. | ||
123 | * @sum: initial sum to be added in (32bit unfolded) | ||
124 | * | ||
125 | * Returns the 32bit unfolded internet checksum of the buffer. | ||
126 | * Before filling it in it needs to be csum_fold()'ed. | ||
127 | * buff should be aligned to a 64bit boundary if possible. | ||
128 | */ | ||
129 | extern __wsum csum_partial(const void *buff, int len, __wsum sum); | ||
130 | |||
131 | #define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER 1 | ||
132 | #define HAVE_CSUM_COPY_USER 1 | ||
133 | |||
134 | |||
135 | /* Do not call this directly. Use the wrappers below */ | ||
136 | extern __wsum csum_partial_copy_generic(const void *src, const void *dst, | ||
137 | int len, __wsum sum, | ||
138 | int *src_err_ptr, int *dst_err_ptr); | ||
139 | |||
140 | |||
141 | extern __wsum csum_partial_copy_from_user(const void __user *src, void *dst, | ||
142 | int len, __wsum isum, int *errp); | ||
143 | extern __wsum csum_partial_copy_to_user(const void *src, void __user *dst, | ||
144 | int len, __wsum isum, int *errp); | ||
145 | extern __wsum csum_partial_copy_nocheck(const void *src, void *dst, | ||
146 | int len, __wsum sum); | ||
147 | |||
148 | /* Old names. To be removed. */ | ||
149 | #define csum_and_copy_to_user csum_partial_copy_to_user | ||
150 | #define csum_and_copy_from_user csum_partial_copy_from_user | ||
151 | |||
152 | /** | ||
153 | * ip_compute_csum - Compute an 16bit IP checksum. | ||
154 | * @buff: buffer address. | ||
155 | * @len: length of buffer. | ||
156 | * | ||
157 | * Returns the 16bit folded/inverted checksum of the passed buffer. | ||
158 | * Ready to fill in. | ||
159 | */ | ||
160 | extern __sum16 ip_compute_csum(const void *buff, int len); | ||
161 | |||
162 | /** | ||
163 | * csum_ipv6_magic - Compute checksum of an IPv6 pseudo header. | ||
164 | * @saddr: source address | ||
165 | * @daddr: destination address | ||
166 | * @len: length of packet | ||
167 | * @proto: protocol of packet | ||
168 | * @sum: initial sum (32bit unfolded) to be added in | ||
169 | * | ||
170 | * Computes an IPv6 pseudo header checksum. This sum is added the checksum | ||
171 | * into UDP/TCP packets and contains some link layer information. | ||
172 | * Returns the unfolded 32bit checksum. | ||
173 | */ | ||
174 | |||
175 | struct in6_addr; | ||
176 | |||
177 | #define _HAVE_ARCH_IPV6_CSUM 1 | ||
178 | extern __sum16 | ||
179 | csum_ipv6_magic(const struct in6_addr *saddr, const struct in6_addr *daddr, | ||
180 | __u32 len, unsigned short proto, __wsum sum); | ||
181 | |||
182 | static inline unsigned add32_with_carry(unsigned a, unsigned b) | ||
183 | { | ||
184 | asm("addl %2,%0\n\t" | ||
185 | "adcl $0,%0" | ||
186 | : "=r" (a) | ||
187 | : "0" (a), "r" (b)); | ||
188 | return a; | ||
189 | } | ||
190 | |||
191 | #endif /* ASM_X86__CHECKSUM_64_H */ | ||