From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 16 Apr 2005 15:20:36 -0700 Subject: Linux-2.6.12-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! --- include/asm-parisc/checksum.h | 213 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 213 insertions(+) create mode 100644 include/asm-parisc/checksum.h (limited to 'include/asm-parisc/checksum.h') diff --git a/include/asm-parisc/checksum.h b/include/asm-parisc/checksum.h new file mode 100644 index 00000000000..229cb56fdb7 --- /dev/null +++ b/include/asm-parisc/checksum.h @@ -0,0 +1,213 @@ +#ifndef _PARISC_CHECKSUM_H +#define _PARISC_CHECKSUM_H + +#include + +/* + * 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 + */ +extern unsigned int csum_partial(const unsigned char *, int, unsigned int); + +/* + * 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 + */ +extern unsigned int csum_partial_copy_nocheck(const unsigned char *, unsigned char *, + int, unsigned int); + +/* + * this is a new version of the above that records errors it finds in *errp, + * but continues and zeros the rest of the buffer. + */ +extern unsigned int csum_partial_copy_from_user(const unsigned char __user *src, + unsigned char *dst, int len, unsigned int sum, int *errp); + +/* + * Optimized for IP headers, which always checksum on 4 octet boundaries. + * + * Written by Randolph Chung , and then mucked with by + * LaMont Jones + */ +static inline unsigned short ip_fast_csum(unsigned char * iph, + unsigned int ihl) { + unsigned int sum; + + + __asm__ __volatile__ ( +" ldws,ma 4(%1), %0\n" +" addib,<= -4, %2, 2f\n" +"\n" +" ldws 4(%1), %%r20\n" +" ldws 8(%1), %%r21\n" +" add %0, %%r20, %0\n" +" ldws,ma 12(%1), %%r19\n" +" addc %0, %%r21, %0\n" +" addc %0, %%r19, %0\n" +"1: ldws,ma 4(%1), %%r19\n" +" addib,< 0, %2, 1b\n" +" addc %0, %%r19, %0\n" +"\n" +" extru %0, 31, 16, %%r20\n" +" extru %0, 15, 16, %%r21\n" +" addc %%r20, %%r21, %0\n" +" extru %0, 15, 16, %%r21\n" +" add %0, %%r21, %0\n" +" subi -1, %0, %0\n" +"2:\n" + : "=r" (sum), "=r" (iph), "=r" (ihl) + : "1" (iph), "2" (ihl) + : "r19", "r20", "r21" ); + + return(sum); +} + +/* + * Fold a partial checksum + */ +static inline unsigned int csum_fold(unsigned int sum) +{ + /* add the swapped two 16-bit halves of sum, + a possible carry from adding the two 16-bit halves, + will carry from the lower half into the upper half, + giving us the correct sum in the upper half. */ + sum += (sum << 16) + (sum >> 16); + return (~sum) >> 16; +} + +static inline unsigned long csum_tcpudp_nofold(unsigned long saddr, + unsigned long daddr, + unsigned short len, + unsigned short proto, + unsigned int sum) +{ + __asm__( + " add %1, %0, %0\n" + " addc %2, %0, %0\n" + " addc %3, %0, %0\n" + " addc %%r0, %0, %0\n" + : "=r" (sum) + : "r" (daddr), "r"(saddr), "r"((proto<<16)+len), "0"(sum)); + return sum; +} + +/* + * computes the checksum of the TCP/UDP pseudo-header + * returns a 16-bit checksum, already complemented + */ +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 + */ +static inline unsigned short ip_compute_csum(unsigned char * buf, int len) { + return csum_fold (csum_partial(buf, len, 0)); +} + + +#define _HAVE_ARCH_IPV6_CSUM +static __inline__ unsigned short int csum_ipv6_magic(struct in6_addr *saddr, + struct in6_addr *daddr, + __u16 len, + unsigned short proto, + unsigned int sum) +{ + __asm__ __volatile__ ( + +#if BITS_PER_LONG > 32 + + /* + ** We can execute two loads and two adds per cycle on PA 8000. + ** But add insn's get serialized waiting for the carry bit. + ** Try to keep 4 registers with "live" values ahead of the ALU. + */ + +" ldd,ma 8(%1), %%r19\n" /* get 1st saddr word */ +" ldd,ma 8(%2), %%r20\n" /* get 1st daddr word */ +" add %8, %3, %3\n"/* add 16-bit proto + len */ +" add %%r19, %0, %0\n" +" ldd,ma 8(%1), %%r21\n" /* 2cd saddr */ +" ldd,ma 8(%2), %%r22\n" /* 2cd daddr */ +" add,dc %%r20, %0, %0\n" +" add,dc %%r21, %0, %0\n" +" add,dc %%r22, %0, %0\n" +" add,dc %3, %0, %0\n" /* fold in proto+len | carry bit */ +" extrd,u %0, 31, 32, %%r19\n" /* copy upper half down */ +" depdi 0, 31, 32, %0\n" /* clear upper half */ +" add %%r19, %0, %0\n" /* fold into 32-bits */ +" addc 0, %0, %0\n" /* add carry */ + +#else + + /* + ** For PA 1.x, the insn order doesn't matter as much. + ** Insn stream is serialized on the carry bit here too. + ** result from the previous operation (eg r0 + x) + */ + +" ldw,ma 4(%1), %%r19\n" /* get 1st saddr word */ +" ldw,ma 4(%2), %%r20\n" /* get 1st daddr word */ +" add %8, %3, %3\n" /* add 16-bit proto + len */ +" add %%r19, %0, %0\n" +" ldw,ma 4(%1), %%r21\n" /* 2cd saddr */ +" addc %%r20, %0, %0\n" +" ldw,ma 4(%2), %%r22\n" /* 2cd daddr */ +" addc %%r21, %0, %0\n" +" ldw,ma 4(%1), %%r19\n" /* 3rd saddr */ +" addc %%r22, %0, %0\n" +" ldw,ma 4(%2), %%r20\n" /* 3rd daddr */ +" addc %%r19, %0, %0\n" +" ldw,ma 4(%1), %%r21\n" /* 4th saddr */ +" addc %%r20, %0, %0\n" +" ldw,ma 4(%2), %%r22\n" /* 4th daddr */ +" addc %%r21, %0, %0\n" +" addc %%r22, %0, %0\n" +" addc %3, %0, %0\n" /* fold in proto+len, catch carry */ + +#endif + : "=r" (sum), "=r" (saddr), "=r" (daddr), "=r" (len) + : "0" (sum), "1" (saddr), "2" (daddr), "3" (len), "r" (proto) + : "r19", "r20", "r21", "r22"); + return csum_fold(sum); +} + +/* + * Copy and checksum to user + */ +#define HAVE_CSUM_COPY_USER +static __inline__ unsigned int csum_and_copy_to_user (const unsigned char *src, + unsigned char __user *dst, + int len, int sum, + int *err_ptr) +{ + /* code stolen from include/asm-mips64 */ + sum = csum_partial(src, len, sum); + + if (copy_to_user(dst, src, len)) { + *err_ptr = -EFAULT; + return -1; + } + + return sum; +} + +#endif + -- cgit v1.2.3