diff options
Diffstat (limited to 'arch/score/include/asm/checksum.h')
| -rw-r--r-- | arch/score/include/asm/checksum.h | 235 |
1 files changed, 235 insertions, 0 deletions
diff --git a/arch/score/include/asm/checksum.h b/arch/score/include/asm/checksum.h new file mode 100644 index 00000000000..f909ac3144a --- /dev/null +++ b/arch/score/include/asm/checksum.h @@ -0,0 +1,235 @@ +#ifndef _ASM_SCORE_CHECKSUM_H +#define _ASM_SCORE_CHECKSUM_H + +#include <linux/in6.h> +#include <asm/uaccess.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 void *buff, int len, __wsum sum); +unsigned int csum_partial_copy_from_user(const char *src, char *dst, int len, + unsigned int sum, int *csum_err); +unsigned int csum_partial_copy(const char *src, char *dst, + int len, unsigned int sum); + +/* + * this is a new version of the above that records errors it finds in *errp, + * but continues and zeros the rest of the buffer. + */ + +/* + * 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) +{ + sum = csum_partial(src, len, sum); + if (copy_to_user(dst, src, len)) { + *err_ptr = -EFAULT; + return (__force __wsum) -1; /* invalid checksum */ + } + return sum; +} + + +#define csum_partial_copy_nocheck csum_partial_copy +/* + * Fold a partial checksum without adding pseudo headers + */ + +static inline __sum16 csum_fold(__wsum sum) +{ + /* the while loop is unnecessary really, it's always enough with two + iterations */ + __asm__ __volatile__( + ".set volatile\n\t" + ".set\tr1\n\t" + "slli\tr1,%0, 16\n\t" + "add\t%0,%0, r1\n\t" + "cmp.c\tr1, %0\n\t" + "srli\t%0, %0, 16\n\t" + "bleu\t1f\n\t" + "addi\t%0, 0x1\n\t" + "1:ldi\tr30, 0xffff\n\t" + "xor\t%0, %0, r30\n\t" + "slli\t%0, %0, 16\n\t" + "srli\t%0, %0, 16\n\t" + ".set\tnor1\n\t" + ".set optimize\n\t" + : "=r" (sum) + : "0" (sum)); + return sum; +} + +/* + * This is a version of ip_compute_csum() optimized for IP headers, + * which always checksum on 4 octet boundaries. + * + * By Jorge Cwik <jorge@laser.satlink.net>, adapted for linux by + * Arnt Gulbrandsen. + */ +static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl) +{ + unsigned int sum; + unsigned long dummy; + + __asm__ __volatile__( + ".set volatile\n\t" + ".set\tnor1\n\t" + "lw\t%0, [%1]\n\t" + "subri\t%2, %2, 4\n\t" + "slli\t%2, %2, 2\n\t" + "lw\t%3, [%1, 4]\n\t" + "add\t%2, %2, %1\n\t" + "add\t%0, %0, %3\n\t" + "cmp.c\t%3, %0\n\t" + "lw\t%3, [%1, 8]\n\t" + "bleu\t1f\n\t" + "addi\t%0, 0x1\n\t" + "1:\n\t" + "add\t%0, %0, %3\n\t" + "cmp.c\t%3, %0\n\t" + "lw\t%3, [%1, 12]\n\t" + "bleu\t1f\n\t" + "addi\t%0, 0x1\n\t" + "1:add\t%0, %0, %3\n\t" + "cmp.c\t%3, %0\n\t" + "bleu\t1f\n\t" + "addi\t%0, 0x1\n" + + "1:\tlw\t%3, [%1, 16]\n\t" + "addi\t%1, 4\n\t" + "add\t%0, %0, %3\n\t" + "cmp.c\t%3, %0\n\t" + "bleu\t2f\n\t" + "addi\t%0, 0x1\n" + "2:cmp.c\t%2, %1\n\t" + "bne\t1b\n\t" + + ".set\tr1\n\t" + ".set optimize\n\t" + : "=&r" (sum), "=&r" (iph), "=&r" (ihl), "=&r" (dummy) + : "1" (iph), "2" (ihl)); + + return csum_fold(sum); +} + +static inline __wsum +csum_tcpudp_nofold(__be32 saddr, __be32 daddr, unsigned short len, + unsigned short proto, __wsum sum) +{ + unsigned long tmp = (ntohs(len) << 16) + proto * 256; + __asm__ __volatile__( + ".set volatile\n\t" + "add\t%0, %0, %2\n\t" + "cmp.c\t%2, %0\n\t" + "bleu\t1f\n\t" + "addi\t%0, 0x1\n\t" + "1:\n\t" + "add\t%0, %0, %3\n\t" + "cmp.c\t%3, %0\n\t" + "bleu\t1f\n\t" + "addi\t%0, 0x1\n\t" + "1:\n\t" + "add\t%0, %0, %4\n\t" + "cmp.c\t%4, %0\n\t" + "bleu\t1f\n\t" + "addi\t%0, 0x1\n\t" + "1:\n\t" + ".set optimize\n\t" + : "=r" (sum) + : "0" (daddr), "r"(saddr), + "r" (tmp), + "r" (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 unsigned short ip_compute_csum(const void *buff, int len) +{ + return csum_fold(csum_partial(buff, 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__( + ".set\tnoreorder\t\t\t# csum_ipv6_magic\n\t" + ".set\tnoat\n\t" + "addu\t%0, %5\t\t\t# proto (long in network byte order)\n\t" + "sltu\t$1, %0, %5\n\t" + "addu\t%0, $1\n\t" + "addu\t%0, %6\t\t\t# csum\n\t" + "sltu\t$1, %0, %6\n\t" + "lw\t%1, 0(%2)\t\t\t# four words source address\n\t" + "addu\t%0, $1\n\t" + "addu\t%0, %1\n\t" + "sltu\t$1, %0, %1\n\t" + "lw\t%1, 4(%2)\n\t" + "addu\t%0, $1\n\t" + "addu\t%0, %1\n\t" + "sltu\t$1, %0, %1\n\t" + "lw\t%1, 8(%2)\n\t" + "addu\t%0, $1\n\t" + "addu\t%0, %1\n\t" + "sltu\t$1, %0, %1\n\t" + "lw\t%1, 12(%2)\n\t" + "addu\t%0, $1\n\t" + "addu\t%0, %1\n\t" + "sltu\t$1, %0, %1\n\t" + "lw\t%1, 0(%3)\n\t" + "addu\t%0, $1\n\t" + "addu\t%0, %1\n\t" + "sltu\t$1, %0, %1\n\t" + "lw\t%1, 4(%3)\n\t" + "addu\t%0, $1\n\t" + "addu\t%0, %1\n\t" + "sltu\t$1, %0, %1\n\t" + "lw\t%1, 8(%3)\n\t" + "addu\t%0, $1\n\t" + "addu\t%0, %1\n\t" + "sltu\t$1, %0, %1\n\t" + "lw\t%1, 12(%3)\n\t" + "addu\t%0, $1\n\t" + "addu\t%0, %1\n\t" + "sltu\t$1, %0, %1\n\t" + "addu\t%0, $1\t\t\t# Add final carry\n\t" + ".set\tnoat\n\t" + ".set\tnoreorder" + : "=r" (sum), "=r" (proto) + : "r" (saddr), "r" (daddr), + "0" (htonl(len)), "1" (htonl(proto)), "r" (sum)); + + return csum_fold(sum); +} +#endif /* _ASM_SCORE_CHECKSUM_H */ |