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-rw-r--r--arch/x86/um/asm/checksum_32.h140
1 files changed, 0 insertions, 140 deletions
diff --git a/arch/x86/um/asm/checksum_32.h b/arch/x86/um/asm/checksum_32.h
index caab74252e27..ab77b6f9a4bf 100644
--- a/arch/x86/um/asm/checksum_32.h
+++ b/arch/x86/um/asm/checksum_32.h
@@ -5,145 +5,6 @@
5#ifndef __UM_SYSDEP_CHECKSUM_H 5#ifndef __UM_SYSDEP_CHECKSUM_H
6#define __UM_SYSDEP_CHECKSUM_H 6#define __UM_SYSDEP_CHECKSUM_H
7 7
8#include "linux/in6.h"
9#include "linux/string.h"
10
11/*
12 * computes the checksum of a memory block at buff, length len,
13 * and adds in "sum" (32-bit)
14 *
15 * returns a 32-bit number suitable for feeding into itself
16 * or csum_tcpudp_magic
17 *
18 * this function must be called with even lengths, except
19 * for the last fragment, which may be odd
20 *
21 * it's best to have buff aligned on a 32-bit boundary
22 */
23__wsum csum_partial(const void *buff, int len, __wsum sum);
24
25/*
26 * Note: when you get a NULL pointer exception here this means someone
27 * passed in an incorrect kernel address to one of these functions.
28 *
29 * If you use these functions directly please don't forget the
30 * access_ok().
31 */
32
33static __inline__
34__wsum csum_partial_copy_nocheck(const void *src, void *dst,
35 int len, __wsum sum)
36{
37 memcpy(dst, src, len);
38 return csum_partial(dst, len, sum);
39}
40
41/*
42 * the same as csum_partial, but copies from src while it
43 * checksums, and handles user-space pointer exceptions correctly, when needed.
44 *
45 * here even more important to align src and dst on a 32-bit (or even
46 * better 64-bit) boundary
47 */
48
49static __inline__
50__wsum csum_partial_copy_from_user(const void __user *src, void *dst,
51 int len, __wsum sum, int *err_ptr)
52{
53 if (copy_from_user(dst, src, len)) {
54 *err_ptr = -EFAULT;
55 return (__force __wsum)-1;
56 }
57
58 return csum_partial(dst, len, sum);
59}
60
61/*
62 * This is a version of ip_compute_csum() optimized for IP headers,
63 * which always checksum on 4 octet boundaries.
64 *
65 * By Jorge Cwik <jorge@laser.satlink.net>, adapted for linux by
66 * Arnt Gulbrandsen.
67 */
68static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl)
69{
70 unsigned int sum;
71
72 __asm__ __volatile__(
73 "movl (%1), %0 ;\n"
74 "subl $4, %2 ;\n"
75 "jbe 2f ;\n"
76 "addl 4(%1), %0 ;\n"
77 "adcl 8(%1), %0 ;\n"
78 "adcl 12(%1), %0 ;\n"
79"1: adcl 16(%1), %0 ;\n"
80 "lea 4(%1), %1 ;\n"
81 "decl %2 ;\n"
82 "jne 1b ;\n"
83 "adcl $0, %0 ;\n"
84 "movl %0, %2 ;\n"
85 "shrl $16, %0 ;\n"
86 "addw %w2, %w0 ;\n"
87 "adcl $0, %0 ;\n"
88 "notl %0 ;\n"
89"2: ;\n"
90 /* Since the input registers which are loaded with iph and ipl
91 are modified, we must also specify them as outputs, or gcc
92 will assume they contain their original values. */
93 : "=r" (sum), "=r" (iph), "=r" (ihl)
94 : "1" (iph), "2" (ihl)
95 : "memory");
96 return (__force __sum16)sum;
97}
98
99/*
100 * Fold a partial checksum
101 */
102
103static inline __sum16 csum_fold(__wsum sum)
104{
105 __asm__(
106 "addl %1, %0 ;\n"
107 "adcl $0xffff, %0 ;\n"
108 : "=r" (sum)
109 : "r" ((__force u32)sum << 16),
110 "0" ((__force u32)sum & 0xffff0000)
111 );
112 return (__force __sum16)(~(__force u32)sum >> 16);
113}
114
115static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
116 unsigned short len,
117 unsigned short proto,
118 __wsum sum)
119{
120 __asm__(
121 "addl %1, %0 ;\n"
122 "adcl %2, %0 ;\n"
123 "adcl %3, %0 ;\n"
124 "adcl $0, %0 ;\n"
125 : "=r" (sum)
126 : "g" (daddr), "g"(saddr), "g"((len + proto) << 8), "0"(sum));
127 return sum;
128}
129
130/*
131 * computes the checksum of the TCP/UDP pseudo-header
132 * returns a 16-bit checksum, already complemented
133 */
134static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
135 unsigned short len,
136 unsigned short proto,
137 __wsum sum)
138{
139 return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum));
140}
141
142/*
143 * this routine is used for miscellaneous IP-like checksums, mainly
144 * in icmp.c
145 */
146
147static inline __sum16 ip_compute_csum(const void *buff, int len) 8static inline __sum16 ip_compute_csum(const void *buff, int len)
148{ 9{
149 return csum_fold (csum_partial(buff, len, 0)); 10 return csum_fold (csum_partial(buff, len, 0));
@@ -198,4 +59,3 @@ static __inline__ __wsum csum_and_copy_to_user(const void *src,
198} 59}
199 60
200#endif 61#endif
201