crypto: twofish - add x86_64/avx assembler implementation

This patch adds a x86_64/avx assembler implementation of the Twofish block
cipher. The implementation processes eight blocks in parallel (two 4 block
chunk AVX operations). The table-lookups are done in general-purpose registers.
For small blocksizes the 3way-parallel functions from the twofish-x86_64-3way
module are called. A good performance increase is provided for blocksizes
greater or equal to 128B.

Patch has been tested with tcrypt and automated filesystem tests.

Tcrypt benchmark results:

Intel Core i5-2500 CPU (fam:6, model:42, step:7)

twofish-avx-x86_64 vs. twofish-x86_64-3way
128bit key:                                             (lrw:256bit)    (xts:256bit)
size    ecb-enc ecb-dec cbc-enc cbc-dec ctr-enc ctr-dec lrw-enc lrw-dec xts-enc xts-dec
16B     0.96x   0.97x   1.00x   0.95x   0.97x   0.97x   0.96x   0.95x   0.95x   0.98x
64B     0.99x   0.99x   1.00x   0.99x   0.98x   0.98x   0.99x   0.98x   0.99x   0.98x
256B    1.20x   1.21x   1.00x   1.19x   1.15x   1.14x   1.19x   1.20x   1.18x   1.19x
1024B   1.29x   1.30x   1.00x   1.28x   1.23x   1.24x   1.26x   1.28x   1.26x   1.27x
8192B   1.31x   1.32x   1.00x   1.31x   1.25x   1.25x   1.28x   1.29x   1.28x   1.30x

256bit key:                                             (lrw:384bit)    (xts:512bit)
size    ecb-enc ecb-dec cbc-enc cbc-dec ctr-enc ctr-dec lrw-enc lrw-dec xts-enc xts-dec
16B     0.96x   0.96x   1.00x   0.96x   0.97x   0.98x   0.95x   0.95x   0.95x   0.96x
64B     1.00x   0.99x   1.00x   0.98x   0.98x   1.01x   0.98x   0.98x   0.98x   0.98x
256B    1.20x   1.21x   1.00x   1.21x   1.15x   1.15x   1.19x   1.20x   1.18x   1.19x
1024B   1.29x   1.30x   1.00x   1.28x   1.23x   1.23x   1.26x   1.27x   1.26x   1.27x
8192B   1.31x   1.33x   1.00x   1.31x   1.26x   1.26x   1.29x   1.29x   1.28x   1.30x

twofish-avx-x86_64 vs aes-asm (8kB block):
         128bit  256bit
ecb-enc  1.19x   1.63x
ecb-dec  1.18x   1.62x
cbc-enc  0.75x   1.03x
cbc-dec  1.23x   1.67x
ctr-enc  1.24x   1.65x
ctr-dec  1.24x   1.65x
lrw-enc  1.15x   1.53x
lrw-dec  1.14x   1.52x
xts-enc  1.16x   1.56x
xts-dec  1.16x   1.56x

Signed-off-by: Johannes Goetzfried <Johannes.Goetzfried@informatik.stud.uni-erlangen.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/arch/x86/crypto/twofish-avx-x86_64-asm_64.S b/arch/x86/crypto/twofish-avx-x86_64-asm_64.S
new file mode 100644
index 0000000..fc31b89b
--- /dev/null
+++ b/arch/x86/crypto/twofish-avx-x86_64-asm_64.S
@@ -0,0 +1,301 @@
+/*
+ * Twofish Cipher 8-way parallel algorithm (AVX/x86_64)
+ *
+ * Copyright (C) 2012 Johannes Goetzfried
+ *     <Johannes.Goetzfried@informatik.stud.uni-erlangen.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
+ * USA
+ *
+ */
+
+.file "twofish-avx-x86_64-asm_64.S"
+.text
+
+/* structure of crypto context */
+#define s0	0
+#define s1	1024
+#define s2	2048
+#define s3	3072
+#define w	4096
+#define k	4128
+
+/**********************************************************************
+  8-way AVX twofish
+ **********************************************************************/
+#define CTX %rdi
+
+#define RA1 %xmm0
+#define RB1 %xmm1
+#define RC1 %xmm2
+#define RD1 %xmm3
+
+#define RA2 %xmm4
+#define RB2 %xmm5
+#define RC2 %xmm6
+#define RD2 %xmm7
+
+#define RX %xmm8
+#define RY %xmm9
+
+#define RK1 %xmm10
+#define RK2 %xmm11
+
+#define RID1  %rax
+#define RID1b %al
+#define RID2  %rbx
+#define RID2b %bl
+
+#define RGI1   %rdx
+#define RGI1bl %dl
+#define RGI1bh %dh
+#define RGI2   %rcx
+#define RGI2bl %cl
+#define RGI2bh %ch
+
+#define RGS1  %r8
+#define RGS1d %r8d
+#define RGS2  %r9
+#define RGS2d %r9d
+#define RGS3  %r10
+#define RGS3d %r10d
+
+
+#define lookup_32bit(t0, t1, t2, t3, src, dst) \
+	movb		src ## bl,        RID1b;     \
+	movb		src ## bh,        RID2b;     \
+	movl		t0(CTX, RID1, 4), dst ## d;  \
+	xorl		t1(CTX, RID2, 4), dst ## d;  \
+	shrq $16,	src;                         \
+	movb		src ## bl,        RID1b;     \
+	movb		src ## bh,        RID2b;     \
+	xorl		t2(CTX, RID1, 4), dst ## d;  \
+	xorl		t3(CTX, RID2, 4), dst ## d;
+
+#define G(a, x, t0, t1, t2, t3) \
+	vmovq		a,    RGI1;               \
+	vpsrldq $8,	a,    x;                  \
+	vmovq		x,    RGI2;               \
+	\
+	lookup_32bit(t0, t1, t2, t3, RGI1, RGS1); \
+	shrq $16,	RGI1;                     \
+	lookup_32bit(t0, t1, t2, t3, RGI1, RGS2); \
+	shlq $32,	RGS2;                     \
+	orq		RGS1, RGS2;               \
+	\
+	lookup_32bit(t0, t1, t2, t3, RGI2, RGS1); \
+	shrq $16,	RGI2;                     \
+	lookup_32bit(t0, t1, t2, t3, RGI2, RGS3); \
+	shlq $32,	RGS3;                     \
+	orq		RGS1, RGS3;               \
+	\
+	vmovq		RGS2, x;                  \
+	vpinsrq $1,	RGS3, x, x;
+
+#define encround(a, b, c, d, x, y) \
+	G(a, x, s0, s1, s2, s3);           \
+	G(b, y, s1, s2, s3, s0);           \
+	vpaddd			x, y,   x; \
+	vpaddd			y, x,   y; \
+	vpaddd			x, RK1, x; \
+	vpaddd			y, RK2, y; \
+	vpxor			x, c,   c; \
+	vpsrld $1,		c, x;      \
+	vpslld $(32 - 1),	c, c;      \
+	vpor			c, x,   c; \
+	vpslld $1,		d, x;      \
+	vpsrld $(32 - 1),	d, d;      \
+	vpor			d, x,   d; \
+	vpxor			d, y,   d;
+
+#define decround(a, b, c, d, x, y) \
+	G(a, x, s0, s1, s2, s3);           \
+	G(b, y, s1, s2, s3, s0);           \
+	vpaddd			x, y,   x; \
+	vpaddd			y, x,   y; \
+	vpaddd			y, RK2, y; \
+	vpxor			d, y,   d; \
+	vpsrld $1,		d, y;      \
+	vpslld $(32 - 1),	d, d;      \
+	vpor			d, y,   d; \
+	vpslld $1,		c, y;      \
+	vpsrld $(32 - 1),	c, c;      \
+	vpor			c, y,   c; \
+	vpaddd			x, RK1, x; \
+	vpxor			x, c,   c;
+
+#define encrypt_round(n, a, b, c, d) \
+	vbroadcastss (k+4*(2*(n)))(CTX),   RK1;           \
+	vbroadcastss (k+4*(2*(n)+1))(CTX), RK2;           \
+	encround(a ## 1, b ## 1, c ## 1, d ## 1, RX, RY); \
+	encround(a ## 2, b ## 2, c ## 2, d ## 2, RX, RY);
+
+#define decrypt_round(n, a, b, c, d) \
+	vbroadcastss (k+4*(2*(n)))(CTX),   RK1;           \
+	vbroadcastss (k+4*(2*(n)+1))(CTX), RK2;           \
+	decround(a ## 1, b ## 1, c ## 1, d ## 1, RX, RY); \
+	decround(a ## 2, b ## 2, c ## 2, d ## 2, RX, RY);
+
+#define encrypt_cycle(n) \
+	encrypt_round((2*n), RA, RB, RC, RD);       \
+	encrypt_round(((2*n) + 1), RC, RD, RA, RB);
+
+#define decrypt_cycle(n) \
+	decrypt_round(((2*n) + 1), RC, RD, RA, RB); \
+	decrypt_round((2*n), RA, RB, RC, RD);
+
+
+#define transpose_4x4(x0, x1, x2, x3, t0, t1, t2) \
+	vpunpckldq		x1, x0, t0; \
+	vpunpckhdq		x1, x0, t2; \
+	vpunpckldq		x3, x2, t1; \
+	vpunpckhdq		x3, x2, x3; \
+	\
+	vpunpcklqdq		t1, t0, x0; \
+	vpunpckhqdq		t1, t0, x1; \
+	vpunpcklqdq		x3, t2, x2; \
+	vpunpckhqdq		x3, t2, x3;
+
+#define inpack_blocks(in, x0, x1, x2, x3, wkey, t0, t1, t2) \
+	vpxor (0*4*4)(in),	wkey, x0; \
+	vpxor (1*4*4)(in),	wkey, x1; \
+	vpxor (2*4*4)(in),	wkey, x2; \
+	vpxor (3*4*4)(in),	wkey, x3; \
+	\
+	transpose_4x4(x0, x1, x2, x3, t0, t1, t2)
+
+#define outunpack_blocks(out, x0, x1, x2, x3, wkey, t0, t1, t2) \
+	transpose_4x4(x0, x1, x2, x3, t0, t1, t2) \
+	\
+	vpxor		x0, wkey, x0;     \
+	vmovdqu 	x0, (0*4*4)(out); \
+	vpxor		x1, wkey, x1;     \
+	vmovdqu		x1, (1*4*4)(out); \
+	vpxor		x2, wkey, x2;     \
+	vmovdqu		x2, (2*4*4)(out); \
+	vpxor		x3, wkey, x3;     \
+	vmovdqu		x3, (3*4*4)(out);
+
+#define outunpack_xor_blocks(out, x0, x1, x2, x3, wkey, t0, t1, t2) \
+	transpose_4x4(x0, x1, x2, x3, t0, t1, t2) \
+	\
+	vpxor		x0, wkey, x0;         \
+	vpxor		(0*4*4)(out), x0, x0; \
+	vmovdqu 	x0, (0*4*4)(out);     \
+	vpxor		x1, wkey, x1;         \
+	vpxor		(1*4*4)(out), x1, x1; \
+	vmovdqu	        x1, (1*4*4)(out);     \
+	vpxor		x2, wkey, x2;         \
+	vpxor           (2*4*4)(out), x2, x2; \
+	vmovdqu		x2, (2*4*4)(out);     \
+	vpxor		x3, wkey, x3;         \
+	vpxor           (3*4*4)(out), x3, x3; \
+	vmovdqu		x3, (3*4*4)(out);
+
+.align 8
+.global __twofish_enc_blk_8way
+.type   __twofish_enc_blk_8way,@function;
+
+__twofish_enc_blk_8way:
+	/* input:
+	 *	%rdi: ctx, CTX
+	 *	%rsi: dst
+	 *	%rdx: src
+	 *	%rcx: bool, if true: xor output
+	 */
+
+	pushq %rbx;
+	pushq %rcx;
+
+	vmovdqu w(CTX), RK1;
+
+	leaq (4*4*4)(%rdx), %rax;
+	inpack_blocks(%rdx, RA1, RB1, RC1, RD1, RK1, RX, RY, RK2);
+	inpack_blocks(%rax, RA2, RB2, RC2, RD2, RK1, RX, RY, RK2);
+
+	xorq RID1, RID1;
+	xorq RID2, RID2;
+
+	encrypt_cycle(0);
+	encrypt_cycle(1);
+	encrypt_cycle(2);
+	encrypt_cycle(3);
+	encrypt_cycle(4);
+	encrypt_cycle(5);
+	encrypt_cycle(6);
+	encrypt_cycle(7);
+
+	vmovdqu (w+4*4)(CTX), RK1;
+
+	popq %rcx;
+	popq %rbx;
+
+	leaq (4*4*4)(%rsi), %rax;
+	leaq (4*4*4)(%rax), %rdx;
+
+	testb %cl, %cl;
+	jnz __enc_xor8;
+
+	outunpack_blocks(%rsi, RC1, RD1, RA1, RB1, RK1, RX, RY, RK2);
+	outunpack_blocks(%rax, RC2, RD2, RA2, RB2, RK1, RX, RY, RK2);
+
+	ret;
+
+__enc_xor8:
+	outunpack_xor_blocks(%rsi, RC1, RD1, RA1, RB1, RK1, RX, RY, RK2);
+	outunpack_xor_blocks(%rax, RC2, RD2, RA2, RB2, RK1, RX, RY, RK2);
+
+	ret;
+
+.align 8
+.global twofish_dec_blk_8way
+.type   twofish_dec_blk_8way,@function;
+
+twofish_dec_blk_8way:
+	/* input:
+	 *	%rdi: ctx, CTX
+	 *	%rsi: dst
+	 *	%rdx: src
+	 */
+
+	pushq %rbx;
+
+	vmovdqu (w+4*4)(CTX), RK1;
+
+	leaq (4*4*4)(%rdx), %rax;
+	inpack_blocks(%rdx, RC1, RD1, RA1, RB1, RK1, RX, RY, RK2);
+	inpack_blocks(%rax, RC2, RD2, RA2, RB2, RK1, RX, RY, RK2);
+
+	xorq RID1, RID1;
+	xorq RID2, RID2;
+
+	decrypt_cycle(7);
+	decrypt_cycle(6);
+	decrypt_cycle(5);
+	decrypt_cycle(4);
+	decrypt_cycle(3);
+	decrypt_cycle(2);
+	decrypt_cycle(1);
+	decrypt_cycle(0);
+
+	vmovdqu (w)(CTX), RK1;
+
+	popq %rbx;
+
+	leaq (4*4*4)(%rsi), %rax;
+	outunpack_blocks(%rsi, RA1, RB1, RC1, RD1, RK1, RX, RY, RK2);
+	outunpack_blocks(%rax, RA2, RB2, RC2, RD2, RK1, RX, RY, RK2);
+
+	ret;