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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-h8300/checksum.h | |
download | op-kernel-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip op-kernel-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'include/asm-h8300/checksum.h')
-rw-r--r-- | include/asm-h8300/checksum.h | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/include/asm-h8300/checksum.h b/include/asm-h8300/checksum.h new file mode 100644 index 0000000..3051931 --- /dev/null +++ b/include/asm-h8300/checksum.h @@ -0,0 +1,105 @@ +#ifndef _H8300_CHECKSUM_H +#define _H8300_CHECKSUM_H + +/* + * computes the checksum of a memory block at buff, length len, + * and adds in "sum" (32-bit) + * + * returns a 32-bit number suitable for feeding into itself + * or csum_tcpudp_magic + * + * this function must be called with even lengths, except + * for the last fragment, which may be odd + * + * it's best to have buff aligned on a 32-bit boundary + */ +unsigned int csum_partial(const unsigned char * buff, int len, unsigned int sum); + +/* + * the same as csum_partial, but copies from src while it + * checksums + * + * here even more important to align src and dst on a 32-bit (or even + * better 64-bit) boundary + */ + +unsigned int csum_partial_copy(const char *src, char *dst, int len, int sum); + + +/* + * the same as csum_partial_copy, but copies from user space. + * + * here even more important to align src and dst on a 32-bit (or even + * better 64-bit) boundary + */ + +extern unsigned int csum_partial_copy_from_user(const char *src, char *dst, + int len, int sum, int *csum_err); + +#define csum_partial_copy_nocheck(src, dst, len, sum) \ + csum_partial_copy((src), (dst), (len), (sum)) + +unsigned short ip_fast_csum(unsigned char *iph, unsigned int ihl); + + +/* + * Fold a partial checksum + */ + +static inline unsigned int csum_fold(unsigned int sum) +{ + __asm__("mov.l %0,er0\n\t" + "add.w e0,r0\n\t" + "xor.w e0,e0\n\t" + "rotxl.w e0\n\t" + "add.w e0,r0\n\t" + "sub.w e0,e0\n\t" + "mov.l er0,%0" + : "=r"(sum) + : "0"(sum) + : "er0"); + return ~sum; +} + + +/* + * computes the checksum of the TCP/UDP pseudo-header + * returns a 16-bit checksum, already complemented + */ + +static inline unsigned int +csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr, unsigned short len, + unsigned short proto, unsigned int sum) +{ + __asm__ ("sub.l er0,er0\n\t" + "add.l %2,%0\n\t" + "addx #0,r0l\n\t" + "add.l %3,%0\n\t" + "addx #0,r0l\n\t" + "add.l %4,%0\n\t" + "addx #0,r0l\n\t" + "add.l er0,%0\n\t" + "bcc 1f\n\t" + "inc.l #1,%0\n" + "1:" + : "=&r" (sum) + : "0" (sum), "r" (daddr), "r" (saddr), "r" (len + proto) + :"er0"); + return sum; +} + +static inline unsigned short int +csum_tcpudp_magic(unsigned long saddr, unsigned long daddr, unsigned short len, + unsigned short proto, unsigned int sum) +{ + return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum)); +} + +/* + * this routine is used for miscellaneous IP-like checksums, mainly + * in icmp.c + */ + +extern unsigned short ip_compute_csum(const unsigned char * buff, int len); + +#endif /* _H8300_CHECKSUM_H */ |