include/asm-m68knommu/checksum.h

   1 #ifndef _M68K_CHECKSUM_H
   2 #define _M68K_CHECKSUM_H
   3
   4 #include <linux/in6.h>
   5
   6 /*
   7  * computes the checksum of a memory block at buff, length len,
   8  * and adds in "sum" (32-bit)
   9  *
  10  * returns a 32-bit number suitable for feeding into itself
  11  * or csum_tcpudp_magic
  12  *
  13  * this function must be called with even lengths, except
  14  * for the last fragment, which may be odd
  15  *
  16  * it's best to have buff aligned on a 32-bit boundary
  17  */
  18 unsigned int csum_partial(const unsigned char * buff, int len, unsigned int sum);
  19
  20 /*
  21  * the same as csum_partial, but copies from src while it
  22  * checksums
  23  *
  24  * here even more important to align src and dst on a 32-bit (or even
  25  * better 64-bit) boundary
  26  */
  27
  28 unsigned int csum_partial_copy(const unsigned char *src, unsigned char *dst,
  29         int len, int sum);
  30
  31
  32 /*
  33  * the same as csum_partial_copy, but copies from user space.
  34  *
  35  * here even more important to align src and dst on a 32-bit (or even
  36  * better 64-bit) boundary
  37  */
  38
  39 extern unsigned int csum_partial_copy_from_user(const unsigned char *src,
  40         unsigned char *dst, int len, int sum, int *csum_err);
  41
  42 #define csum_partial_copy_nocheck(src, dst, len, sum)   \
  43         csum_partial_copy((src), (dst), (len), (sum))
  44
  45 unsigned short ip_fast_csum(unsigned char *iph, unsigned int ihl);
  46
  47 /*
  48  *      Fold a partial checksum
  49  */
  50
  51 static inline unsigned int csum_fold(unsigned int sum)
  52 {
  53 #ifdef CONFIG_COLDFIRE
  54         sum = (sum & 0xffff) + (sum >> 16);
  55         sum = (sum & 0xffff) + (sum >> 16);
  56 #else
  57         unsigned int tmp = sum;
  58         __asm__("swap %1\n\t"
  59                 "addw %1, %0\n\t"
  60                 "clrw %1\n\t"
  61                 "addxw %1, %0"
  62                 : "=&d" (sum), "=&d" (tmp)
  63                 : "0" (sum), "1" (sum));
  64 #endif
  65         return ~sum;
  66 }
  67
  68
  69 /*
  70  * computes the checksum of the TCP/UDP pseudo-header
  71  * returns a 16-bit checksum, already complemented
  72  */
  73
  74 static inline unsigned int
  75 csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr, unsigned short len,
  76                   unsigned short proto, unsigned int sum)
  77 {
  78         __asm__ ("addl  %1,%0\n\t"
  79                  "addxl %4,%0\n\t"
  80                  "addxl %5,%0\n\t"
  81                  "clrl %1\n\t"
  82                  "addxl %1,%0"
  83                  : "=&d" (sum), "=&d" (saddr)
  84                  : "0" (daddr), "1" (saddr), "d" (len + proto),
  85                    "d"(sum));
  86         return sum;
  87 }
  88
  89 static inline unsigned short int
  90 csum_tcpudp_magic(unsigned long saddr, unsigned long daddr, unsigned short len,
  91                   unsigned short proto, unsigned int sum)
  92 {
  93         return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum));
  94 }
  95
  96 /*
  97  * this routine is used for miscellaneous IP-like checksums, mainly
  98  * in icmp.c
  99  */
 100
 101 extern unsigned short ip_compute_csum(const unsigned char * buff, int len);
 102
 103 #define _HAVE_ARCH_IPV6_CSUM
 104 static __inline__ unsigned short int
 105 csum_ipv6_magic(struct in6_addr *saddr, struct in6_addr *daddr,
 106                 __u32 len, unsigned short proto, unsigned int sum)
 107 {
 108         register unsigned long tmp;
 109         __asm__("addl %2@,%0\n\t"
 110                 "movel %2@(4),%1\n\t"
 111                 "addxl %1,%0\n\t"
 112                 "movel %2@(8),%1\n\t"
 113                 "addxl %1,%0\n\t"
 114                 "movel %2@(12),%1\n\t"
 115                 "addxl %1,%0\n\t"
 116                 "movel %3@,%1\n\t"
 117                 "addxl %1,%0\n\t"
 118                 "movel %3@(4),%1\n\t"
 119                 "addxl %1,%0\n\t"
 120                 "movel %3@(8),%1\n\t"
 121                 "addxl %1,%0\n\t"
 122                 "movel %3@(12),%1\n\t"
 123                 "addxl %1,%0\n\t"
 124                 "addxl %4,%0\n\t"
 125                 "clrl %1\n\t"
 126                 "addxl %1,%0"
 127                 : "=&d" (sum), "=&d" (tmp)
 128                 : "a" (saddr), "a" (daddr), "d" (len + proto),
 129                   "0" (sum));
 130
 131         return csum_fold(sum);
 132 }
 133
 134 #endif /* _M68K_CHECKSUM_H */