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Diffstat (limited to 'arch/parisc/include/asm/checksum.h')
| -rw-r--r-- | arch/parisc/include/asm/checksum.h | 210 |
1 files changed, 210 insertions, 0 deletions
diff --git a/arch/parisc/include/asm/checksum.h b/arch/parisc/include/asm/checksum.h new file mode 100644 index 000000000..c84b2fcb1 --- /dev/null +++ b/arch/parisc/include/asm/checksum.h @@ -0,0 +1,210 @@ +#ifndef _PARISC_CHECKSUM_H +#define _PARISC_CHECKSUM_H + +#include <linux/in6.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 + */ +extern __wsum csum_partial(const void *, int, __wsum); + +/* + * 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 __wsum csum_partial_copy_nocheck(const void *, void *, int, __wsum); + +/* + * 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 __wsum csum_partial_copy_from_user(const void __user *src, + void *dst, int len, __wsum sum, int *errp); + +/* + * Optimized for IP headers, which always checksum on 4 octet boundaries. + * + * Written by Randolph Chung <tausq@debian.org>, and then mucked with by + * LaMont Jones <lamont@debian.org> + */ +static inline __sum16 ip_fast_csum(const void *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", "memory"); + + return (__force __sum16)sum; +} + +/* + * Fold a partial checksum + */ +static inline __sum16 csum_fold(__wsum csum) +{ + u32 sum = (__force u32)csum; + /* 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 (__force __sum16)(~sum >> 16); +} + +static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr, + unsigned short len, + unsigned short proto, + __wsum 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+len), "0"(sum)); + return sum; +} + +/* + * computes the checksum of the TCP/UDP pseudo-header + * returns a 16-bit checksum, already complemented + */ +static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr, + unsigned short len, + unsigned short proto, + __wsum 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 __sum16 ip_compute_csum(const void *buf, int len) +{ + return csum_fold (csum_partial(buf, len, 0)); +} + + +#define _HAVE_ARCH_IPV6_CSUM +static __inline__ __sum16 csum_ipv6_magic(const struct in6_addr *saddr, + const struct in6_addr *daddr, + __u32 len, unsigned short proto, + __wsum 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", "memory"); + return csum_fold(sum); +} + +/* + * Copy and checksum to user + */ +#define HAVE_CSUM_COPY_USER +static __inline__ __wsum csum_and_copy_to_user(const void *src, + void __user *dst, + int len, __wsum 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 (__force __wsum)-1; + } + + return sum; +} + +#endif + |