| /* SPDX-License-Identifier: GPL-2.0 */ |
| #ifndef _ASM_SCORE_CHECKSUM_H |
| #define _ASM_SCORE_CHECKSUM_H |
| |
| #include <linux/in6.h> |
| #include <linux/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, __u32 len, |
| __u8 proto, __wsum sum) |
| { |
| unsigned long tmp = (len + proto) << 8; |
| __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, __u32 len, |
| __u8 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, __u8 proto, __wsum sum) |
| { |
| __asm__ __volatile__( |
| ".set\tvolatile\t\t\t# csum_ipv6_magic\n\t" |
| "add\t%0, %0, %5\t\t\t# proto (long in network byte order)\n\t" |
| "cmp.c\t%5, %0\n\t" |
| "bleu 1f\n\t" |
| "addi\t%0, 0x1\n\t" |
| "1:add\t%0, %0, %6\t\t\t# csum\n\t" |
| "cmp.c\t%6, %0\n\t" |
| "lw\t%1, [%2, 0]\t\t\t# four words source address\n\t" |
| "bleu 1f\n\t" |
| "addi\t%0, 0x1\n\t" |
| "1:add\t%0, %0, %1\n\t" |
| "cmp.c\t%1, %0\n\t" |
| "1:lw\t%1, [%2, 4]\n\t" |
| "bleu 1f\n\t" |
| "addi\t%0, 0x1\n\t" |
| "1:add\t%0, %0, %1\n\t" |
| "cmp.c\t%1, %0\n\t" |
| "lw\t%1, [%2,8]\n\t" |
| "bleu 1f\n\t" |
| "addi\t%0, 0x1\n\t" |
| "1:add\t%0, %0, %1\n\t" |
| "cmp.c\t%1, %0\n\t" |
| "lw\t%1, [%2, 12]\n\t" |
| "bleu 1f\n\t" |
| "addi\t%0, 0x1\n\t" |
| "1:add\t%0, %0,%1\n\t" |
| "cmp.c\t%1, %0\n\t" |
| "lw\t%1, [%3, 0]\n\t" |
| "bleu 1f\n\t" |
| "addi\t%0, 0x1\n\t" |
| "1:add\t%0, %0, %1\n\t" |
| "cmp.c\t%1, %0\n\t" |
| "lw\t%1, [%3, 4]\n\t" |
| "bleu 1f\n\t" |
| "addi\t%0, 0x1\n\t" |
| "1:add\t%0, %0, %1\n\t" |
| "cmp.c\t%1, %0\n\t" |
| "lw\t%1, [%3, 8]\n\t" |
| "bleu 1f\n\t" |
| "addi\t%0, 0x1\n\t" |
| "1:add\t%0, %0, %1\n\t" |
| "cmp.c\t%1, %0\n\t" |
| "lw\t%1, [%3, 12]\n\t" |
| "bleu 1f\n\t" |
| "addi\t%0, 0x1\n\t" |
| "1:add\t%0, %0, %1\n\t" |
| "cmp.c\t%1, %0\n\t" |
| "bleu 1f\n\t" |
| "addi\t%0, 0x1\n\t" |
| "1:\n\t" |
| ".set\toptimize" |
| : "=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 */ |