| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | #ifndef _H8300_CHECKSUM_H |
| 2 | #define _H8300_CHECKSUM_H |
| 3 | |
| 4 | /* |
| 5 | * computes the checksum of a memory block at buff, length len, |
| 6 | * and adds in "sum" (32-bit) |
| 7 | * |
| 8 | * returns a 32-bit number suitable for feeding into itself |
| 9 | * or csum_tcpudp_magic |
| 10 | * |
| 11 | * this function must be called with even lengths, except |
| 12 | * for the last fragment, which may be odd |
| 13 | * |
| 14 | * it's best to have buff aligned on a 32-bit boundary |
| 15 | */ |
| 16 | unsigned int csum_partial(const unsigned char * buff, int len, unsigned int sum); |
| 17 | |
| 18 | /* |
| 19 | * the same as csum_partial, but copies from src while it |
| 20 | * checksums |
| 21 | * |
| 22 | * here even more important to align src and dst on a 32-bit (or even |
| 23 | * better 64-bit) boundary |
| 24 | */ |
| 25 | |
| 26 | unsigned int csum_partial_copy(const char *src, char *dst, int len, int sum); |
| 27 | |
| 28 | |
| 29 | /* |
| 30 | * the same as csum_partial_copy, but copies from user space. |
| 31 | * |
| 32 | * here even more important to align src and dst on a 32-bit (or even |
| 33 | * better 64-bit) boundary |
| 34 | */ |
| 35 | |
| 36 | extern unsigned int csum_partial_copy_from_user(const char *src, char *dst, |
| 37 | int len, int sum, int *csum_err); |
| 38 | |
| 39 | #define csum_partial_copy_nocheck(src, dst, len, sum) \ |
| 40 | csum_partial_copy((src), (dst), (len), (sum)) |
| 41 | |
| 42 | unsigned short ip_fast_csum(unsigned char *iph, unsigned int ihl); |
| 43 | |
| 44 | |
| 45 | /* |
| 46 | * Fold a partial checksum |
| 47 | */ |
| 48 | |
| 49 | static inline unsigned int csum_fold(unsigned int sum) |
| 50 | { |
| 51 | __asm__("mov.l %0,er0\n\t" |
| 52 | "add.w e0,r0\n\t" |
| 53 | "xor.w e0,e0\n\t" |
| 54 | "rotxl.w e0\n\t" |
| 55 | "add.w e0,r0\n\t" |
| 56 | "sub.w e0,e0\n\t" |
| 57 | "mov.l er0,%0" |
| 58 | : "=r"(sum) |
| 59 | : "0"(sum) |
| 60 | : "er0"); |
| 61 | return ~sum; |
| 62 | } |
| 63 | |
| 64 | |
| 65 | /* |
| 66 | * computes the checksum of the TCP/UDP pseudo-header |
| 67 | * returns a 16-bit checksum, already complemented |
| 68 | */ |
| 69 | |
| 70 | static inline unsigned int |
| 71 | csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr, unsigned short len, |
| 72 | unsigned short proto, unsigned int sum) |
| 73 | { |
| 74 | __asm__ ("sub.l er0,er0\n\t" |
| 75 | "add.l %2,%0\n\t" |
| 76 | "addx #0,r0l\n\t" |
| 77 | "add.l %3,%0\n\t" |
| 78 | "addx #0,r0l\n\t" |
| 79 | "add.l %4,%0\n\t" |
| 80 | "addx #0,r0l\n\t" |
| 81 | "add.l er0,%0\n\t" |
| 82 | "bcc 1f\n\t" |
| 83 | "inc.l #1,%0\n" |
| 84 | "1:" |
| 85 | : "=&r" (sum) |
| 86 | : "0" (sum), "r" (daddr), "r" (saddr), "r" (len + proto) |
| 87 | :"er0"); |
| 88 | return sum; |
| 89 | } |
| 90 | |
| 91 | static inline unsigned short int |
| 92 | csum_tcpudp_magic(unsigned long saddr, unsigned long daddr, unsigned short len, |
| 93 | unsigned short proto, unsigned int sum) |
| 94 | { |
| 95 | return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum)); |
| 96 | } |
| 97 | |
| 98 | /* |
| 99 | * this routine is used for miscellaneous IP-like checksums, mainly |
| 100 | * in icmp.c |
| 101 | */ |
| 102 | |
| 103 | extern unsigned short ip_compute_csum(const unsigned char * buff, int len); |
| 104 | |
| 105 | #endif /* _H8300_CHECKSUM_H */ |