The generic csum_ipv6_magic() generates a pretty bad result 00000000 <csum_ipv6_magic>: 0: 81 23 00 00 lwz r9,0(r3) 4: 81 03 00 04 lwz r8,4(r3) 8: 7c e7 4a 14 add r7,r7,r9 c: 7d 29 38 10 subfc r9,r9,r7 10: 7d 4a 51 10 subfe r10,r10,r10 14: 7d 27 42 14 add r9,r7,r8 18: 7d 2a 48 50 subf r9,r10,r9 1c: 80 e3 00 08 lwz r7,8(r3) 20: 7d 08 48 10 subfc r8,r8,r9 24: 7d 4a 51 10 subfe r10,r10,r10 28: 7d 29 3a 14 add r9,r9,r7 2c: 81 03 00 0c lwz r8,12(r3) 30: 7d 2a 48 50 subf r9,r10,r9 34: 7c e7 48 10 subfc r7,r7,r9 38: 7d 4a 51 10 subfe r10,r10,r10 3c: 7d 29 42 14 add r9,r9,r8 40: 7d 2a 48 50 subf r9,r10,r9 44: 80 e4 00 00 lwz r7,0(r4) 48: 7d 08 48 10 subfc r8,r8,r9 4c: 7d 4a 51 10 subfe r10,r10,r10 50: 7d 29 3a 14 add r9,r9,r7 54: 7d 2a 48 50 subf r9,r10,r9 58: 81 04 00 04 lwz r8,4(r4) 5c: 7c e7 48 10 subfc r7,r7,r9 60: 7d 4a 51 10 subfe r10,r10,r10 64: 7d 29 42 14 add r9,r9,r8 68: 7d 2a 48 50 subf r9,r10,r9 6c: 80 e4 00 08 lwz r7,8(r4) 70: 7d 08 48 10 subfc r8,r8,r9 74: 7d 4a 51 10 subfe r10,r10,r10 78: 7d 29 3a 14 add r9,r9,r7 7c: 7d 2a 48 50 subf r9,r10,r9 80: 81 04 00 0c lwz r8,12(r4) 84: 7c e7 48 10 subfc r7,r7,r9 88: 7d 4a 51 10 subfe r10,r10,r10 8c: 7d 29 42 14 add r9,r9,r8 90: 7d 2a 48 50 subf r9,r10,r9 94: 7d 08 48 10 subfc r8,r8,r9 98: 7d 4a 51 10 subfe r10,r10,r10 9c: 7d 29 2a 14 add r9,r9,r5 a0: 7d 2a 48 50 subf r9,r10,r9 a4: 7c a5 48 10 subfc r5,r5,r9 a8: 7c 63 19 10 subfe r3,r3,r3 ac: 7d 29 32 14 add r9,r9,r6 b0: 7d 23 48 50 subf r9,r3,r9 b4: 7c c6 48 10 subfc r6,r6,r9 b8: 7c 63 19 10 subfe r3,r3,r3 bc: 7c 63 48 50 subf r3,r3,r9 c0: 54 6a 80 3e rotlwi r10,r3,16 c4: 7c 63 52 14 add r3,r3,r10 c8: 7c 63 18 f8 not r3,r3 cc: 54 63 84 3e rlwinm r3,r3,16,16,31 d0: 4e 80 00 20 blr
This patch implements it in assembly for PPC32 Link: https://github.com/linuxppc/linux/issues/9 Signed-off-by: Christophe Leroy <christophe.le...@c-s.fr> --- arch/powerpc/include/asm/checksum.h | 8 ++++++++ arch/powerpc/lib/checksum_32.S | 33 +++++++++++++++++++++++++++++++++ 2 files changed, 41 insertions(+) diff --git a/arch/powerpc/include/asm/checksum.h b/arch/powerpc/include/asm/checksum.h index 54065caa40b3..c41c280c252f 100644 --- a/arch/powerpc/include/asm/checksum.h +++ b/arch/powerpc/include/asm/checksum.h @@ -13,6 +13,7 @@ #include <asm-generic/checksum.h> #else #include <linux/bitops.h> +#include <linux/in6.h> /* * Computes the checksum of a memory block at src, length len, * and adds in "sum" (32-bit), while copying the block to dst. @@ -211,6 +212,13 @@ static inline __sum16 ip_compute_csum(const void *buff, int len) return csum_fold(csum_partial(buff, len, 0)); } +#ifdef CONFIG_PPC32 +#define _HAVE_ARCH_IPV6_CSUM +__sum16 csum_ipv6_magic(const struct in6_addr *saddr, + const struct in6_addr *daddr, + __u32 len, __u8 proto, __wsum sum); +#endif + #endif #endif /* __KERNEL__ */ #endif diff --git a/arch/powerpc/lib/checksum_32.S b/arch/powerpc/lib/checksum_32.S index 9a671c774b22..f9c047145696 100644 --- a/arch/powerpc/lib/checksum_32.S +++ b/arch/powerpc/lib/checksum_32.S @@ -293,3 +293,36 @@ dst_error: EX_TABLE(51b, dst_error); EXPORT_SYMBOL(csum_partial_copy_generic) + +/* + * static inline __sum16 csum_ipv6_magic(const struct in6_addr *saddr, + * const struct in6_addr *daddr, + * __u32 len, __u8 proto, __wsum sum) + */ + +_GLOBAL(csum_ipv6_magic) + lwz r8, 0(r3) + lwz r9, 4(r3) + lwz r10, 8(r3) + lwz r11, 12(r3) + addc r0, r5, r6 + adde r0, r0, r7 + adde r0, r0, r8 + adde r0, r0, r9 + adde r0, r0, r10 + adde r0, r0, r11 + lwz r8, 0(r4) + lwz r9, 4(r4) + lwz r10, 8(r4) + lwz r11, 12(r4) + adde r0, r0, r8 + adde r0, r0, r9 + adde r0, r0, r10 + adde r0, r0, r11 + addze r0 + rotlwi r3, r0, 16 + add r3, r0, r3 + not r3, r3 + rlwinm r3, r3, 16, 16, 31 + blr +EXPORT_SYMBOL(csum_ipv6_magic) -- 2.13.3
