~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/arch/powerpc/include/asm/checksum.h

Version: ~ [ linux-5.4-rc3 ] ~ [ linux-5.3.6 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.79 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.149 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.196 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.196 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.75 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.102 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 #ifndef _ASM_POWERPC_CHECKSUM_H
  2 #define _ASM_POWERPC_CHECKSUM_H
  3 #ifdef __KERNEL__
  4 
  5 /*
  6  * This program is free software; you can redistribute it and/or
  7  * modify it under the terms of the GNU General Public License
  8  * as published by the Free Software Foundation; either version
  9  * 2 of the License, or (at your option) any later version.
 10  */
 11 
 12 #ifdef CONFIG_GENERIC_CSUM
 13 #include <asm-generic/checksum.h>
 14 #else
 15 /*
 16  * Computes the checksum of a memory block at src, length len,
 17  * and adds in "sum" (32-bit), while copying the block to dst.
 18  * If an access exception occurs on src or dst, it stores -EFAULT
 19  * to *src_err or *dst_err respectively (if that pointer is not
 20  * NULL), and, for an error on src, zeroes the rest of dst.
 21  *
 22  * Like csum_partial, this must be called with even lengths,
 23  * except for the last fragment.
 24  */
 25 extern __wsum csum_partial_copy_generic(const void *src, void *dst,
 26                                               int len, __wsum sum,
 27                                               int *src_err, int *dst_err);
 28 
 29 #define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER
 30 extern __wsum csum_and_copy_from_user(const void __user *src, void *dst,
 31                                       int len, __wsum sum, int *err_ptr);
 32 #define HAVE_CSUM_COPY_USER
 33 extern __wsum csum_and_copy_to_user(const void *src, void __user *dst,
 34                                     int len, __wsum sum, int *err_ptr);
 35 
 36 #define csum_partial_copy_nocheck(src, dst, len, sum)   \
 37         csum_partial_copy_generic((src), (dst), (len), (sum), NULL, NULL)
 38 
 39 
 40 /*
 41  * turns a 32-bit partial checksum (e.g. from csum_partial) into a
 42  * 1's complement 16-bit checksum.
 43  */
 44 static inline __sum16 csum_fold(__wsum sum)
 45 {
 46         unsigned int tmp;
 47 
 48         /* swap the two 16-bit halves of sum */
 49         __asm__("rlwinm %0,%1,16,0,31" : "=r" (tmp) : "r" (sum));
 50         /* if there is a carry from adding the two 16-bit halves,
 51            it will carry from the lower half into the upper half,
 52            giving us the correct sum in the upper half. */
 53         return (__force __sum16)(~((__force u32)sum + tmp) >> 16);
 54 }
 55 
 56 static inline u32 from64to32(u64 x)
 57 {
 58         /* add up 32-bit and 32-bit for 32+c bit */
 59         x = (x & 0xffffffff) + (x >> 32);
 60         /* add up carry.. */
 61         x = (x & 0xffffffff) + (x >> 32);
 62         return (u32)x;
 63 }
 64 
 65 static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr, __u32 len,
 66                                         __u8 proto, __wsum sum)
 67 {
 68 #ifdef __powerpc64__
 69         u64 s = (__force u32)sum;
 70 
 71         s += (__force u32)saddr;
 72         s += (__force u32)daddr;
 73 #ifdef __BIG_ENDIAN__
 74         s += proto + len;
 75 #else
 76         s += (proto + len) << 8;
 77 #endif
 78         return (__force __wsum) from64to32(s);
 79 #else
 80     __asm__("\n\
 81         addc %0,%0,%1 \n\
 82         adde %0,%0,%2 \n\
 83         adde %0,%0,%3 \n\
 84         addze %0,%0 \n\
 85         "
 86         : "=r" (sum)
 87         : "r" (daddr), "r"(saddr), "r"(proto + len), ""(sum));
 88         return sum;
 89 #endif
 90 }
 91 
 92 /*
 93  * computes the checksum of the TCP/UDP pseudo-header
 94  * returns a 16-bit checksum, already complemented
 95  */
 96 static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr, __u32 len,
 97                                         __u8 proto, __wsum sum)
 98 {
 99         return csum_fold(csum_tcpudp_nofold(saddr, daddr, len, proto, sum));
100 }
101 
102 #define HAVE_ARCH_CSUM_ADD
103 static inline __wsum csum_add(__wsum csum, __wsum addend)
104 {
105 #ifdef __powerpc64__
106         u64 res = (__force u64)csum;
107 #endif
108         if (__builtin_constant_p(csum) && csum == 0)
109                 return addend;
110         if (__builtin_constant_p(addend) && addend == 0)
111                 return csum;
112 
113 #ifdef __powerpc64__
114         res += (__force u64)addend;
115         return (__force __wsum) from64to32(res);
116 #else
117         asm("addc %0,%0,%1;"
118             "addze %0,%0;"
119             : "+r" (csum) : "r" (addend) : "xer");
120         return csum;
121 #endif
122 }
123 
124 /*
125  * This is a version of ip_compute_csum() optimized for IP headers,
126  * which always checksum on 4 octet boundaries.  ihl is the number
127  * of 32-bit words and is always >= 5.
128  */
129 static inline __wsum ip_fast_csum_nofold(const void *iph, unsigned int ihl)
130 {
131         const u32 *ptr = (const u32 *)iph + 1;
132 #ifdef __powerpc64__
133         unsigned int i;
134         u64 s = *(const u32 *)iph;
135 
136         for (i = 0; i < ihl - 1; i++, ptr++)
137                 s += *ptr;
138         return (__force __wsum)from64to32(s);
139 #else
140         __wsum sum, tmp;
141 
142         asm("mtctr %3;"
143             "addc %0,%4,%5;"
144             "1: lwzu %1, 4(%2);"
145             "adde %0,%0,%1;"
146             "bdnz 1b;"
147             "addze %0,%0;"
148             : "=r" (sum), "=r" (tmp), "+b" (ptr)
149             : "r" (ihl - 2), "r" (*(const u32 *)iph), "r" (*ptr)
150             : "ctr", "xer", "memory");
151 
152         return sum;
153 #endif
154 }
155 
156 static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl)
157 {
158         return csum_fold(ip_fast_csum_nofold(iph, ihl));
159 }
160 
161 /*
162  * computes the checksum of a memory block at buff, length len,
163  * and adds in "sum" (32-bit)
164  *
165  * returns a 32-bit number suitable for feeding into itself
166  * or csum_tcpudp_magic
167  *
168  * this function must be called with even lengths, except
169  * for the last fragment, which may be odd
170  *
171  * it's best to have buff aligned on a 32-bit boundary
172  */
173 __wsum __csum_partial(const void *buff, int len, __wsum sum);
174 
175 static inline __wsum csum_partial(const void *buff, int len, __wsum sum)
176 {
177         if (__builtin_constant_p(len) && len <= 16 && (len & 1) == 0) {
178                 if (len == 2)
179                         sum = csum_add(sum, (__force __wsum)*(const u16 *)buff);
180                 if (len >= 4)
181                         sum = csum_add(sum, (__force __wsum)*(const u32 *)buff);
182                 if (len == 6)
183                         sum = csum_add(sum, (__force __wsum)
184                                             *(const u16 *)(buff + 4));
185                 if (len >= 8)
186                         sum = csum_add(sum, (__force __wsum)
187                                             *(const u32 *)(buff + 4));
188                 if (len == 10)
189                         sum = csum_add(sum, (__force __wsum)
190                                             *(const u16 *)(buff + 8));
191                 if (len >= 12)
192                         sum = csum_add(sum, (__force __wsum)
193                                             *(const u32 *)(buff + 8));
194                 if (len == 14)
195                         sum = csum_add(sum, (__force __wsum)
196                                             *(const u16 *)(buff + 12));
197                 if (len >= 16)
198                         sum = csum_add(sum, (__force __wsum)
199                                             *(const u32 *)(buff + 12));
200         } else if (__builtin_constant_p(len) && (len & 3) == 0) {
201                 sum = csum_add(sum, ip_fast_csum_nofold(buff, len >> 2));
202         } else {
203                 sum = __csum_partial(buff, len, sum);
204         }
205         return sum;
206 }
207 
208 /*
209  * this routine is used for miscellaneous IP-like checksums, mainly
210  * in icmp.c
211  */
212 static inline __sum16 ip_compute_csum(const void *buff, int len)
213 {
214         return csum_fold(csum_partial(buff, len, 0));
215 }
216 
217 #endif
218 #endif /* __KERNEL__ */
219 #endif
220 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp