From: Ard Biesheuvel ardb@kernel.org

Upstream commit 86ad60a65f29dd862a11c22bb4b5be28d6c5cef1

The XTS asm helper arrangement is a bit odd: the 8-way stride helper consists of back-to-back calls to the 4-way core transforms, which are called indirectly, based on a boolean that indicates whether we are performing encryption or decryption.

Given how costly indirect calls are on x86, let's switch to direct calls, and given how the 8-way stride doesn't really add anything substantial, use a 4-way stride instead, and make the asm core routine deal with any multiple of 4 blocks. Since 512 byte sectors or 4 KB blocks are the typical quantities XTS operates on, increase the stride exported to the glue helper to 512 bytes as well.

As a result, the number of indirect calls is reduced from 3 per 64 bytes of in/output to 1 per 512 bytes of in/output, which produces a 65% speedup when operating on 1 KB blocks (measured on a Intel(R) Core(TM) i7-8650U CPU)

Fixes: 9697fa39efd3f ("x86/retpoline/crypto: Convert crypto assembler indirect jumps") Tested-by: Eric Biggers ebiggers@google.com # x86_64 Signed-off-by: Ard Biesheuvel ardb@kernel.org Signed-off-by: Herbert Xu herbert@gondor.apana.org.au [ardb: rebase onto stable/linux-5.4.y] Signed-off-by: Ard Biesheuvel ardb@kernel.org ---

Please apply on top of backports of

9c1e8836edbb crypto: x86 - Regularize glue function prototypes 032d049ea0f4 crypto: aesni - Use TEST %reg,%reg instead of CMP $0,%reg

arch/x86/crypto/aesni-intel_asm.S | 115 ++++++++++++++++++----------- arch/x86/crypto/aesni-intel_glue.c | 25 ++++--- 2 files changed, 84 insertions(+), 56 deletions(-)

diff --git a/arch/x86/crypto/aesni-intel_asm.S b/arch/x86/crypto/aesni-intel_asm.S index f10f044c887c..dd954d8db629 100644 --- a/arch/x86/crypto/aesni-intel_asm.S +++ b/arch/x86/crypto/aesni-intel_asm.S @@ -2726,25 +2726,18 @@ ENDPROC(aesni_ctr_enc) pxor CTR, IV;

/* - * void aesni_xts_crypt8(const struct crypto_aes_ctx *ctx, u8 *dst, - * const u8 *src, bool enc, le128 *iv) + * void aesni_xts_encrypt(const struct crypto_aes_ctx *ctx, u8 *dst, + * const u8 *src, unsigned int len, le128 *iv) */ -ENTRY(aesni_xts_crypt8) +ENTRY(aesni_xts_encrypt) FRAME_BEGIN - testb %cl, %cl - movl $0, %ecx - movl $240, %r10d - leaq _aesni_enc4, %r11 - leaq _aesni_dec4, %rax - cmovel %r10d, %ecx - cmoveq %rax, %r11

movdqa .Lgf128mul_x_ble_mask, GF128MUL_MASK movups (IVP), IV

mov 480(KEYP), KLEN - addq %rcx, KEYP

+.Lxts_enc_loop4: movdqa IV, STATE1 movdqu 0x00(INP), INC pxor INC, STATE1 @@ -2768,71 +2761,103 @@ ENTRY(aesni_xts_crypt8) pxor INC, STATE4 movdqu IV, 0x30(OUTP)

- CALL_NOSPEC %r11 + call _aesni_enc4

movdqu 0x00(OUTP), INC pxor INC, STATE1 movdqu STATE1, 0x00(OUTP)

- _aesni_gf128mul_x_ble() - movdqa IV, STATE1 - movdqu 0x40(INP), INC - pxor INC, STATE1 - movdqu IV, 0x40(OUTP) - movdqu 0x10(OUTP), INC pxor INC, STATE2 movdqu STATE2, 0x10(OUTP)

- _aesni_gf128mul_x_ble() - movdqa IV, STATE2 - movdqu 0x50(INP), INC - pxor INC, STATE2 - movdqu IV, 0x50(OUTP) - movdqu 0x20(OUTP), INC pxor INC, STATE3 movdqu STATE3, 0x20(OUTP)

- _aesni_gf128mul_x_ble() - movdqa IV, STATE3 - movdqu 0x60(INP), INC - pxor INC, STATE3 - movdqu IV, 0x60(OUTP) - movdqu 0x30(OUTP), INC pxor INC, STATE4 movdqu STATE4, 0x30(OUTP)

_aesni_gf128mul_x_ble() - movdqa IV, STATE4 - movdqu 0x70(INP), INC - pxor INC, STATE4 - movdqu IV, 0x70(OUTP)

- _aesni_gf128mul_x_ble() + add $64, INP + add $64, OUTP + sub $64, LEN + ja .Lxts_enc_loop4 + movups IV, (IVP)

- CALL_NOSPEC %r11 + FRAME_END + ret +ENDPROC(aesni_xts_encrypt) + +/* + * void aesni_xts_decrypt(const struct crypto_aes_ctx *ctx, u8 *dst, + * const u8 *src, unsigned int len, le128 *iv) + */ +ENTRY(aesni_xts_decrypt) + FRAME_BEGIN + + movdqa .Lgf128mul_x_ble_mask, GF128MUL_MASK + movups (IVP), IV + + mov 480(KEYP), KLEN + add $240, KEYP

- movdqu 0x40(OUTP), INC +.Lxts_dec_loop4: + movdqa IV, STATE1 + movdqu 0x00(INP), INC pxor INC, STATE1 - movdqu STATE1, 0x40(OUTP) + movdqu IV, 0x00(OUTP)

- movdqu 0x50(OUTP), INC + _aesni_gf128mul_x_ble() + movdqa IV, STATE2 + movdqu 0x10(INP), INC + pxor INC, STATE2 + movdqu IV, 0x10(OUTP) + + _aesni_gf128mul_x_ble() + movdqa IV, STATE3 + movdqu 0x20(INP), INC + pxor INC, STATE3 + movdqu IV, 0x20(OUTP) + + _aesni_gf128mul_x_ble() + movdqa IV, STATE4 + movdqu 0x30(INP), INC + pxor INC, STATE4 + movdqu IV, 0x30(OUTP) + + call _aesni_dec4 + + movdqu 0x00(OUTP), INC + pxor INC, STATE1 + movdqu STATE1, 0x00(OUTP) + + movdqu 0x10(OUTP), INC pxor INC, STATE2 - movdqu STATE2, 0x50(OUTP) + movdqu STATE2, 0x10(OUTP)

- movdqu 0x60(OUTP), INC + movdqu 0x20(OUTP), INC pxor INC, STATE3 - movdqu STATE3, 0x60(OUTP) + movdqu STATE3, 0x20(OUTP)

- movdqu 0x70(OUTP), INC + movdqu 0x30(OUTP), INC pxor INC, STATE4 - movdqu STATE4, 0x70(OUTP) + movdqu STATE4, 0x30(OUTP) + + _aesni_gf128mul_x_ble() + + add $64, INP + add $64, OUTP + sub $64, LEN + ja .Lxts_dec_loop4 + + movups IV, (IVP)

FRAME_END ret -ENDPROC(aesni_xts_crypt8) +ENDPROC(aesni_xts_decrypt)

#endif diff --git a/arch/x86/crypto/aesni-intel_glue.c b/arch/x86/crypto/aesni-intel_glue.c index f795310d3da7..18cfb76daa23 100644 --- a/arch/x86/crypto/aesni-intel_glue.c +++ b/arch/x86/crypto/aesni-intel_glue.c @@ -97,6 +97,12 @@ asmlinkage void aesni_cbc_dec(struct crypto_aes_ctx *ctx, u8 *out, #define AVX_GEN2_OPTSIZE 640 #define AVX_GEN4_OPTSIZE 4096

+asmlinkage void aesni_xts_encrypt(const struct crypto_aes_ctx *ctx, u8 *out, + const u8 *in, unsigned int len, u8 *iv); + +asmlinkage void aesni_xts_decrypt(const struct crypto_aes_ctx *ctx, u8 *out, + const u8 *in, unsigned int len, u8 *iv); + #ifdef CONFIG_X86_64

static void (*aesni_ctr_enc_tfm)(struct crypto_aes_ctx *ctx, u8 *out, @@ -104,9 +110,6 @@ static void (*aesni_ctr_enc_tfm)(struct crypto_aes_ctx *ctx, u8 *out, asmlinkage void aesni_ctr_enc(struct crypto_aes_ctx *ctx, u8 *out, const u8 *in, unsigned int len, u8 *iv);

-asmlinkage void aesni_xts_crypt8(const struct crypto_aes_ctx *ctx, u8 *out, - const u8 *in, bool enc, le128 *iv); - /* asmlinkage void aesni_gcm_enc() * void *ctx, AES Key schedule. Starts on a 16 byte boundary. * struct gcm_context_data. May be uninitialized. @@ -558,14 +561,14 @@ static void aesni_xts_dec(const void *ctx, u8 *dst, const u8 *src, le128 *iv) glue_xts_crypt_128bit_one(ctx, dst, src, iv, aesni_dec); }

-static void aesni_xts_enc8(const void *ctx, u8 *dst, const u8 *src, le128 *iv) +static void aesni_xts_enc32(const void *ctx, u8 *dst, const u8 *src, le128 *iv) { - aesni_xts_crypt8(ctx, dst, src, true, iv); + aesni_xts_encrypt(ctx, dst, src, 32 * AES_BLOCK_SIZE, (u8 *)iv); }

-static void aesni_xts_dec8(const void *ctx, u8 *dst, const u8 *src, le128 *iv) +static void aesni_xts_dec32(const void *ctx, u8 *dst, const u8 *src, le128 *iv) { - aesni_xts_crypt8(ctx, dst, src, false, iv); + aesni_xts_decrypt(ctx, dst, src, 32 * AES_BLOCK_SIZE, (u8 *)iv); }

static const struct common_glue_ctx aesni_enc_xts = { @@ -573,8 +576,8 @@ static const struct common_glue_ctx aesni_enc_xts = { .fpu_blocks_limit = 1,

.funcs = { { - .num_blocks = 8, - .fn_u = { .xts = aesni_xts_enc8 } + .num_blocks = 32, + .fn_u = { .xts = aesni_xts_enc32 } }, { .num_blocks = 1, .fn_u = { .xts = aesni_xts_enc } @@ -586,8 +589,8 @@ static const struct common_glue_ctx aesni_dec_xts = { .fpu_blocks_limit = 1,

.funcs = { { - .num_blocks = 8, - .fn_u = { .xts = aesni_xts_dec8 } + .num_blocks = 32, + .fn_u = { .xts = aesni_xts_dec32 } }, { .num_blocks = 1, .fn_u = { .xts = aesni_xts_dec }