The generic csum_ipv6_magic() generates a pretty bad result 00000000 <csum_ipv6_magic>: (PPC32) 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
0000000000000000 <.csum_ipv6_magic>: (PPC64) 0: 81 23 00 00 lwz r9,0(r3) 4: 80 03 00 04 lwz r0,4(r3) 8: 81 63 00 08 lwz r11,8(r3) c: 7c e7 4a 14 add r7,r7,r9 10: 7f 89 38 40 cmplw cr7,r9,r7 14: 7d 47 02 14 add r10,r7,r0 18: 7d 30 10 26 mfocrf r9,1 1c: 55 29 f7 fe rlwinm r9,r9,30,31,31 20: 7d 4a 4a 14 add r10,r10,r9 24: 7f 80 50 40 cmplw cr7,r0,r10 28: 7d 2a 5a 14 add r9,r10,r11 2c: 80 03 00 0c lwz r0,12(r3) 30: 81 44 00 00 lwz r10,0(r4) 34: 7d 10 10 26 mfocrf r8,1 38: 55 08 f7 fe rlwinm r8,r8,30,31,31 3c: 7d 29 42 14 add r9,r9,r8 40: 81 04 00 04 lwz r8,4(r4) 44: 7f 8b 48 40 cmplw cr7,r11,r9 48: 7d 29 02 14 add r9,r9,r0 4c: 7d 70 10 26 mfocrf r11,1 50: 55 6b f7 fe rlwinm r11,r11,30,31,31 54: 7d 29 5a 14 add r9,r9,r11 58: 7f 80 48 40 cmplw cr7,r0,r9 5c: 7d 29 52 14 add r9,r9,r10 60: 7c 10 10 26 mfocrf r0,1 64: 54 00 f7 fe rlwinm r0,r0,30,31,31 68: 7d 69 02 14 add r11,r9,r0 6c: 7f 8a 58 40 cmplw cr7,r10,r11 70: 7c 0b 42 14 add r0,r11,r8 74: 81 44 00 08 lwz r10,8(r4) 78: 7c f0 10 26 mfocrf r7,1 7c: 54 e7 f7 fe rlwinm r7,r7,30,31,31 80: 7c 00 3a 14 add r0,r0,r7 84: 7f 88 00 40 cmplw cr7,r8,r0 88: 7d 20 52 14 add r9,r0,r10 8c: 80 04 00 0c lwz r0,12(r4) 90: 7d 70 10 26 mfocrf r11,1 94: 55 6b f7 fe rlwinm r11,r11,30,31,31 98: 7d 29 5a 14 add r9,r9,r11 9c: 7f 8a 48 40 cmplw cr7,r10,r9 a0: 7d 29 02 14 add r9,r9,r0 a4: 7d 70 10 26 mfocrf r11,1 a8: 55 6b f7 fe rlwinm r11,r11,30,31,31 ac: 7d 29 5a 14 add r9,r9,r11 b0: 7f 80 48 40 cmplw cr7,r0,r9 b4: 7d 29 2a 14 add r9,r9,r5 b8: 7c 10 10 26 mfocrf r0,1 bc: 54 00 f7 fe rlwinm r0,r0,30,31,31 c0: 7d 29 02 14 add r9,r9,r0 c4: 7f 85 48 40 cmplw cr7,r5,r9 c8: 7c 09 32 14 add r0,r9,r6 cc: 7d 50 10 26 mfocrf r10,1 d0: 55 4a f7 fe rlwinm r10,r10,30,31,31 d4: 7c 00 52 14 add r0,r0,r10 d8: 7f 80 30 40 cmplw cr7,r0,r6 dc: 7d 30 10 26 mfocrf r9,1 e0: 55 29 ef fe rlwinm r9,r9,29,31,31 e4: 7c 09 02 14 add r0,r9,r0 e8: 54 03 80 3e rotlwi r3,r0,16 ec: 7c 03 02 14 add r0,r3,r0 f0: 7c 03 00 f8 not r3,r0 f4: 78 63 84 22 rldicl r3,r3,48,48 f8: 4e 80 00 20 blr This patch implements it in assembly for both PPC32 and PPC64 Link: https://github.com/linuxppc/linux/issues/9 Signed-off-by: Christophe Leroy <christophe.le...@c-s.fr> --- v3: Add support for PPC64 (please review, especially whether instructions order in optimal) v2: Fix number of args in final addze arch/powerpc/include/asm/checksum.h | 6 ++++++ arch/powerpc/lib/checksum_32.S | 33 +++++++++++++++++++++++++++++++++ arch/powerpc/lib/checksum_64.S | 28 ++++++++++++++++++++++++++++ 3 files changed, 67 insertions(+) diff --git a/arch/powerpc/include/asm/checksum.h b/arch/powerpc/include/asm/checksum.h index 54065caa40b3..a78a57e5058d 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 +212,11 @@ static inline __sum16 ip_compute_csum(const void *buff, int len) return csum_fold(csum_partial(buff, len, 0)); } +#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 /* __KERNEL__ */ #endif diff --git a/arch/powerpc/lib/checksum_32.S b/arch/powerpc/lib/checksum_32.S index 9a671c774b22..9167ab088f04 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, r0 + rotlwi r3, r0, 16 + add r3, r0, r3 + not r3, r3 + rlwinm r3, r3, 16, 16, 31 + blr +EXPORT_SYMBOL(csum_ipv6_magic) diff --git a/arch/powerpc/lib/checksum_64.S b/arch/powerpc/lib/checksum_64.S index d7f1a966136e..66900baf5600 100644 --- a/arch/powerpc/lib/checksum_64.S +++ b/arch/powerpc/lib/checksum_64.S @@ -429,3 +429,31 @@ dstnr; stb r6,0(r4) stw r6,0(r8) blr 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) + ld r8, 0(r3) + ld r9, 8(r3) + add r5, r5, r6 + addc r0, r8, r9 + ld r10, 0(r4) + ld r11, 8(r4) + adde r0, r0, r10 + add r5, r5, r7 + adde r0, r0, r11 + adde r0, r0, r5 + addze r0, r0 + rotldi r3 ,r0, 32 /* fold two 32 bit halves together */ + add r3, r0, r3 + srdi r0, r3, 32 + rotlwi r3, r0, 16 /* fold two 16 bit halves together */ + add r3, r0, r3 + not r3, r3 + rlwinm r3, r3, 16, 16, 31 + blr +EXPORT_SYMBOL(csum_ipv6_magic) -- 2.13.3