From 2fffee536c6875bdf546cee0045fed8faa5ea51f Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Mon, 27 Aug 2018 17:38:12 +0200 Subject: [PATCH] crypto: arm64/crct10dif - implement non-Crypto Extensions alternative The arm64 implementation of the CRC-T10DIF algorithm uses the 64x64 bit polynomial multiplication instructions, which are optional in the architecture, and if these instructions are not available, we fall back to the C routine which is slow and inefficient. So let's reuse the 64x64 bit PMULL alternative from the GHASH driver that uses a sequence of ~40 instructions involving 8x8 bit PMULL and some shifting and masking. This is a lot slower than the original, but it is still twice as fast as the current [unoptimized] C code on Cortex-A53, and it is time invariant and much easier on the D-cache. Signed-off-by: Ard Biesheuvel Signed-off-by: Herbert Xu --- arch/arm64/crypto/crct10dif-ce-core.S | 154 ++++++++++++++++++++++++++++++++++ arch/arm64/crypto/crct10dif-ce-glue.c | 10 ++- 2 files changed, 162 insertions(+), 2 deletions(-) diff --git a/arch/arm64/crypto/crct10dif-ce-core.S b/arch/arm64/crypto/crct10dif-ce-core.S index a399510..9e82e8e 100644 --- a/arch/arm64/crypto/crct10dif-ce-core.S +++ b/arch/arm64/crypto/crct10dif-ce-core.S @@ -80,6 +80,145 @@ vzr .req v13 + ad .req v14 + bd .req v10 + + k00_16 .req v15 + k32_48 .req v16 + + t3 .req v17 + t4 .req v18 + t5 .req v19 + t6 .req v20 + t7 .req v21 + t8 .req v22 + t9 .req v23 + + perm1 .req v24 + perm2 .req v25 + perm3 .req v26 + perm4 .req v27 + + bd1 .req v28 + bd2 .req v29 + bd3 .req v30 + bd4 .req v31 + + .macro __pmull_init_p64 + .endm + + .macro __pmull_pre_p64, bd + .endm + + .macro __pmull_init_p8 + // k00_16 := 0x0000000000000000_000000000000ffff + // k32_48 := 0x00000000ffffffff_0000ffffffffffff + movi k32_48.2d, #0xffffffff + mov k32_48.h[2], k32_48.h[0] + ushr k00_16.2d, k32_48.2d, #32 + + // prepare the permutation vectors + mov_q x5, 0x080f0e0d0c0b0a09 + movi perm4.8b, #8 + dup perm1.2d, x5 + eor perm1.16b, perm1.16b, perm4.16b + ushr perm2.2d, perm1.2d, #8 + ushr perm3.2d, perm1.2d, #16 + ushr perm4.2d, perm1.2d, #24 + sli perm2.2d, perm1.2d, #56 + sli perm3.2d, perm1.2d, #48 + sli perm4.2d, perm1.2d, #40 + .endm + + .macro __pmull_pre_p8, bd + tbl bd1.16b, {\bd\().16b}, perm1.16b + tbl bd2.16b, {\bd\().16b}, perm2.16b + tbl bd3.16b, {\bd\().16b}, perm3.16b + tbl bd4.16b, {\bd\().16b}, perm4.16b + .endm + +__pmull_p8_core: +.L__pmull_p8_core: + ext t4.8b, ad.8b, ad.8b, #1 // A1 + ext t5.8b, ad.8b, ad.8b, #2 // A2 + ext t6.8b, ad.8b, ad.8b, #3 // A3 + + pmull t4.8h, t4.8b, bd.8b // F = A1*B + pmull t8.8h, ad.8b, bd1.8b // E = A*B1 + pmull t5.8h, t5.8b, bd.8b // H = A2*B + pmull t7.8h, ad.8b, bd2.8b // G = A*B2 + pmull t6.8h, t6.8b, bd.8b // J = A3*B + pmull t9.8h, ad.8b, bd3.8b // I = A*B3 + pmull t3.8h, ad.8b, bd4.8b // K = A*B4 + b 0f + +.L__pmull_p8_core2: + tbl t4.16b, {ad.16b}, perm1.16b // A1 + tbl t5.16b, {ad.16b}, perm2.16b // A2 + tbl t6.16b, {ad.16b}, perm3.16b // A3 + + pmull2 t4.8h, t4.16b, bd.16b // F = A1*B + pmull2 t8.8h, ad.16b, bd1.16b // E = A*B1 + pmull2 t5.8h, t5.16b, bd.16b // H = A2*B + pmull2 t7.8h, ad.16b, bd2.16b // G = A*B2 + pmull2 t6.8h, t6.16b, bd.16b // J = A3*B + pmull2 t9.8h, ad.16b, bd3.16b // I = A*B3 + pmull2 t3.8h, ad.16b, bd4.16b // K = A*B4 + +0: eor t4.16b, t4.16b, t8.16b // L = E + F + eor t5.16b, t5.16b, t7.16b // M = G + H + eor t6.16b, t6.16b, t9.16b // N = I + J + + uzp1 t8.2d, t4.2d, t5.2d + uzp2 t4.2d, t4.2d, t5.2d + uzp1 t7.2d, t6.2d, t3.2d + uzp2 t6.2d, t6.2d, t3.2d + + // t4 = (L) (P0 + P1) << 8 + // t5 = (M) (P2 + P3) << 16 + eor t8.16b, t8.16b, t4.16b + and t4.16b, t4.16b, k32_48.16b + + // t6 = (N) (P4 + P5) << 24 + // t7 = (K) (P6 + P7) << 32 + eor t7.16b, t7.16b, t6.16b + and t6.16b, t6.16b, k00_16.16b + + eor t8.16b, t8.16b, t4.16b + eor t7.16b, t7.16b, t6.16b + + zip2 t5.2d, t8.2d, t4.2d + zip1 t4.2d, t8.2d, t4.2d + zip2 t3.2d, t7.2d, t6.2d + zip1 t6.2d, t7.2d, t6.2d + + ext t4.16b, t4.16b, t4.16b, #15 + ext t5.16b, t5.16b, t5.16b, #14 + ext t6.16b, t6.16b, t6.16b, #13 + ext t3.16b, t3.16b, t3.16b, #12 + + eor t4.16b, t4.16b, t5.16b + eor t6.16b, t6.16b, t3.16b + ret +ENDPROC(__pmull_p8_core) + + .macro __pmull_p8, rq, ad, bd, i + .ifnc \bd, v10 + .err + .endif + mov ad.16b, \ad\().16b + .ifb \i + pmull \rq\().8h, \ad\().8b, bd.8b // D = A*B + .else + pmull2 \rq\().8h, \ad\().16b, bd.16b // D = A*B + .endif + + bl .L__pmull_p8_core\i + + eor \rq\().16b, \rq\().16b, t4.16b + eor \rq\().16b, \rq\().16b, t6.16b + .endm + .macro fold64, p, reg1, reg2 ldp q11, q12, [arg2], #0x20 @@ -106,6 +245,7 @@ CPU_LE( ext v12.16b, v12.16b, v12.16b, #8 ) __pmull_\p \reg, \reg, v10, 2 .ifnb \rk ldr_l q10, \rk, x8 + __pmull_pre_\p v10 .endif eor v7.16b, v7.16b, v8.16b eor v7.16b, v7.16b, \reg\().16b @@ -128,6 +268,8 @@ CPU_LE( ext v12.16b, v12.16b, v12.16b, #8 ) movi vzr.16b, #0 // init zero register + __pmull_init_\p + // adjust the 16-bit initial_crc value, scale it to 32 bits lsl arg1_low32, arg1_low32, #16 @@ -176,6 +318,7 @@ CPU_LE( ext v7.16b, v7.16b, v7.16b, #8 ) ldr_l q10, rk3, x8 // xmm10 has rk3 and rk4 // type of pmull instruction // will determine which constant to use + __pmull_pre_\p v10 // // we subtract 256 instead of 128 to save one instruction from the loop @@ -212,6 +355,8 @@ CPU_LE( ext v7.16b, v7.16b, v7.16b, #8 ) ldp q6, q7, [sp, #.Lframe_local_offset + 96] ldr_l q10, rk3, x8 movi vzr.16b, #0 // init zero register + __pmull_init_\p + __pmull_pre_\p v10 endif_yield_neon b .L_fold_64_B_loop_\@ @@ -225,6 +370,7 @@ CPU_LE( ext v7.16b, v7.16b, v7.16b, #8 ) // constants ldr_l q10, rk9, x8 + __pmull_pre_\p v10 fold16 \p, v0, rk11 fold16 \p, v1, rk13 @@ -306,6 +452,7 @@ CPU_LE( ext v1.16b, v1.16b, v1.16b, #8 ) .L_128_done_\@: // compute crc of a 128-bit value ldr_l q10, rk5, x8 // rk5 and rk6 in xmm10 + __pmull_pre_\p v10 // 64b fold ext v0.16b, vzr.16b, v7.16b, #8 @@ -321,6 +468,7 @@ CPU_LE( ext v1.16b, v1.16b, v1.16b, #8 ) // barrett reduction ldr_l q10, rk7, x8 + __pmull_pre_\p v10 mov v0.d[0], v7.d[1] __pmull_\p v0, v0, v10 @@ -352,6 +500,7 @@ CPU_LE( ext v7.16b, v7.16b, v7.16b, #8 ) b.lt .L_less_than_16_left_\@ ldr_l q10, rk1, x8 // rk1 and rk2 in xmm10 + __pmull_pre_\p v10 // update the counter. subtract 32 instead of 16 to save one // instruction from the loop @@ -372,6 +521,11 @@ CPU_LE( ext v7.16b, v7.16b, v7.16b, #8 ) b .L_128_done_\@ .endm +ENTRY(crc_t10dif_pmull_p8) + crc_t10dif_pmull p8 +ENDPROC(crc_t10dif_pmull_p8) + + .align 5 ENTRY(crc_t10dif_pmull_p64) crc_t10dif_pmull p64 ENDPROC(crc_t10dif_pmull_p64) diff --git a/arch/arm64/crypto/crct10dif-ce-glue.c b/arch/arm64/crypto/crct10dif-ce-glue.c index 343a1e9..b461d62 100644 --- a/arch/arm64/crypto/crct10dif-ce-glue.c +++ b/arch/arm64/crypto/crct10dif-ce-glue.c @@ -23,6 +23,7 @@ #define CRC_T10DIF_PMULL_CHUNK_SIZE 16U asmlinkage u16 crc_t10dif_pmull_p64(u16 init_crc, const u8 buf[], u64 len); +asmlinkage u16 crc_t10dif_pmull_p8(u16 init_crc, const u8 buf[], u64 len); static u16 (*crc_t10dif_pmull)(u16 init_crc, const u8 buf[], u64 len); @@ -87,7 +88,10 @@ static struct shash_alg crc_t10dif_alg = { static int __init crc_t10dif_mod_init(void) { - crc_t10dif_pmull = crc_t10dif_pmull_p64; + if (elf_hwcap & HWCAP_PMULL) + crc_t10dif_pmull = crc_t10dif_pmull_p64; + else + crc_t10dif_pmull = crc_t10dif_pmull_p8; return crypto_register_shash(&crc_t10dif_alg); } @@ -97,8 +101,10 @@ static void __exit crc_t10dif_mod_exit(void) crypto_unregister_shash(&crc_t10dif_alg); } -module_cpu_feature_match(PMULL, crc_t10dif_mod_init); +module_cpu_feature_match(ASIMD, crc_t10dif_mod_init); module_exit(crc_t10dif_mod_exit); MODULE_AUTHOR("Ard Biesheuvel "); MODULE_LICENSE("GPL v2"); +MODULE_ALIAS_CRYPTO("crct10dif"); +MODULE_ALIAS_CRYPTO("crct10dif-arm64-ce"); -- 2.7.4