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

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

Version: ~ [ linux-5.13-rc5 ] ~ [ linux-5.12.9 ] ~ [ linux-5.11.22 ] ~ [ linux-5.10.42 ] ~ [ linux-5.9.16 ] ~ [ linux-5.8.18 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.124 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.193 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.235 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.271 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.271 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.18.140 ] ~ [ linux-3.16.85 ] ~ [ linux-3.14.79 ] ~ [ linux-3.12.74 ] ~ [ linux-3.10.108 ] ~ [ 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 /*
 13  * This is a version of ip_compute_csum() optimized for IP headers,
 14  * which always checksum on 4 octet boundaries.  ihl is the number
 15  * of 32-bit words and is always >= 5.
 16  */
 17 #ifdef CONFIG_GENERIC_CSUM
 18 #include <asm-generic/checksum.h>
 19 #else
 20 extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl);
 21 
 22 /*
 23  * computes the checksum of the TCP/UDP pseudo-header
 24  * returns a 16-bit checksum, already complemented
 25  */
 26 extern __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
 27                                         unsigned short len,
 28                                         unsigned short proto,
 29                                         __wsum sum);
 30 
 31 /*
 32  * computes the checksum of a memory block at buff, length len,
 33  * and adds in "sum" (32-bit)
 34  *
 35  * returns a 32-bit number suitable for feeding into itself
 36  * or csum_tcpudp_magic
 37  *
 38  * this function must be called with even lengths, except
 39  * for the last fragment, which may be odd
 40  *
 41  * it's best to have buff aligned on a 32-bit boundary
 42  */
 43 extern __wsum csum_partial(const void *buff, int len, __wsum sum);
 44 
 45 /*
 46  * Computes the checksum of a memory block at src, length len,
 47  * and adds in "sum" (32-bit), while copying the block to dst.
 48  * If an access exception occurs on src or dst, it stores -EFAULT
 49  * to *src_err or *dst_err respectively (if that pointer is not
 50  * NULL), and, for an error on src, zeroes the rest of dst.
 51  *
 52  * Like csum_partial, this must be called with even lengths,
 53  * except for the last fragment.
 54  */
 55 extern __wsum csum_partial_copy_generic(const void *src, void *dst,
 56                                               int len, __wsum sum,
 57                                               int *src_err, int *dst_err);
 58 
 59 #ifdef __powerpc64__
 60 #define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER
 61 extern __wsum csum_and_copy_from_user(const void __user *src, void *dst,
 62                                       int len, __wsum sum, int *err_ptr);
 63 #define HAVE_CSUM_COPY_USER
 64 extern __wsum csum_and_copy_to_user(const void *src, void __user *dst,
 65                                     int len, __wsum sum, int *err_ptr);
 66 #else
 67 /*
 68  * the same as csum_partial, but copies from src to dst while it
 69  * checksums.
 70  */
 71 #define csum_partial_copy_from_user(src, dst, len, sum, errp)   \
 72         csum_partial_copy_generic((__force const void *)(src), (dst), (len), (sum), (errp), NULL)
 73 #endif
 74 
 75 #define csum_partial_copy_nocheck(src, dst, len, sum)   \
 76         csum_partial_copy_generic((src), (dst), (len), (sum), NULL, NULL)
 77 
 78 
 79 /*
 80  * turns a 32-bit partial checksum (e.g. from csum_partial) into a
 81  * 1's complement 16-bit checksum.
 82  */
 83 static inline __sum16 csum_fold(__wsum sum)
 84 {
 85         unsigned int tmp;
 86 
 87         /* swap the two 16-bit halves of sum */
 88         __asm__("rlwinm %0,%1,16,0,31" : "=r" (tmp) : "r" (sum));
 89         /* if there is a carry from adding the two 16-bit halves,
 90            it will carry from the lower half into the upper half,
 91            giving us the correct sum in the upper half. */
 92         return (__force __sum16)(~((__force u32)sum + tmp) >> 16);
 93 }
 94 
 95 /*
 96  * this routine is used for miscellaneous IP-like checksums, mainly
 97  * in icmp.c
 98  */
 99 static inline __sum16 ip_compute_csum(const void *buff, int len)
100 {
101         return csum_fold(csum_partial(buff, len, 0));
102 }
103 
104 static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
105                                      unsigned short len,
106                                      unsigned short proto,
107                                      __wsum sum)
108 {
109 #ifdef __powerpc64__
110         unsigned long s = (__force u32)sum;
111 
112         s += (__force u32)saddr;
113         s += (__force u32)daddr;
114         s += proto + len;
115         s += (s >> 32);
116         return (__force __wsum) s;
117 #else
118     __asm__("\n\
119         addc %0,%0,%1 \n\
120         adde %0,%0,%2 \n\
121         adde %0,%0,%3 \n\
122         addze %0,%0 \n\
123         "
124         : "=r" (sum)
125         : "r" (daddr), "r"(saddr), "r"(proto + len), ""(sum));
126         return sum;
127 #endif
128 }
129 
130 #endif
131 #endif /* __KERNEL__ */
132 #endif
133 

~ [ 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