This is the x86_64 CRC T10 DIF transform accelerated with the PCLMULQDQ instructions. Details discussing the implementation can be found in the paper: "Fast CRC Computation for Generic Polynomials Using PCLMULQDQ Instruction" http://www.intel.com/content/dam/www/public/us/en/documents/white-papers/fast-crc-computation-generic-polynomials-pclmulqdq-paper.pdf Signed-off-by: Tim Chen <tim.c.chen@xxxxxxxxxxxxxxx> --- arch/x86/crypto/crct10dif-pcl-asm_64.S | 643 +++++++++++++++++++++++++++++++++ 1 file changed, 643 insertions(+) create mode 100644 arch/x86/crypto/crct10dif-pcl-asm_64.S diff --git a/arch/x86/crypto/crct10dif-pcl-asm_64.S b/arch/x86/crypto/crct10dif-pcl-asm_64.S new file mode 100644 index 0000000..35e9756 --- /dev/null +++ b/arch/x86/crypto/crct10dif-pcl-asm_64.S @@ -0,0 +1,643 @@ +######################################################################## +# Implement fast CRC-T10DIF computation with SSE and PCLMULQDQ instructions +# +# Copyright (c) 2013, Intel Corporation +# +# Authors: +# Erdinc Ozturk <erdinc.ozturk@xxxxxxxxx> +# Vinodh Gopal <vinodh.gopal@xxxxxxxxx> +# James Guilford <james.guilford@xxxxxxxxx> +# Tim Chen <tim.c.chen@xxxxxxxxxxxxxxx> +# +# This software is available to you under a choice of one of two +# licenses. You may choose to be licensed under the terms of the GNU +# General Public License (GPL) Version 2, available from the file +# COPYING in the main directory of this source tree, or the +# OpenIB.org BSD license below: +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions are +# met: +# +# * Redistributions of source code must retain the above copyright +# notice, this list of conditions and the following disclaimer. +# +# * Redistributions in binary form must reproduce the above copyright +# notice, this list of conditions and the following disclaimer in the +# documentation and/or other materials provided with the +# distribution. +# +# * Neither the name of the Intel Corporation nor the names of its +# contributors may be used to endorse or promote products derived from +# this software without specific prior written permission. +# +# +# THIS SOFTWARE IS PROVIDED BY INTEL CORPORATION ""AS IS"" AND ANY +# EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR +# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL INTEL CORPORATION OR +# CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, +# EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, +# PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR +# PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF +# LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING +# NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS +# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +######################################################################## +# Function API: +# UINT16 crc_t10dif_pcl( +# UINT16 init_crc, //initial CRC value, 16 bits +# const unsigned char *buf, //buffer pointer to calculate CRC on +# UINT64 len //buffer length in bytes (64-bit data) +# ); +# +# Reference paper titled "Fast CRC Computation for Generic +# Polynomials Using PCLMULQDQ Instruction" +# URL: http://www.intel.com/content/dam/www/public/us/en/documents +# /white-papers/fast-crc-computation-generic-polynomials-pclmulqdq-paper.pdf +# +# + +#include <linux/linkage.h> + +.text + +#define arg1 %rdi +#define arg2 %rsi +#define arg3 %rdx + +#define arg1_low32 %edi + +ENTRY(crc_t10dif_pcl) +.align 16 + + # adjust the 16-bit initial_crc value, scale it to 32 bits + shl $16, arg1_low32 + + # Allocate Stack Space + mov %rsp, %rcx + sub $16*2, %rsp + # align stack to 16 byte boundary + and $~(0x10 - 1), %rsp + + # check if smaller than 256 + cmp $256, arg3 + + # for sizes less than 128, we can't fold 64B at a time... + jl _less_than_128 + + + # load the initial crc value + movd arg1_low32, %xmm10 # initial crc + + # crc value does not need to be byte-reflected, but it needs + # to be moved to the high part of the register. + # because data will be byte-reflected and will align with + # initial crc at correct place. + pslldq $12, %xmm10 + + movdqa SHUF_MASK(%rip), %xmm11 + # receive the initial 64B data, xor the initial crc value + movdqu 16*0(arg2), %xmm0 + movdqu 16*1(arg2), %xmm1 + movdqu 16*2(arg2), %xmm2 + movdqu 16*3(arg2), %xmm3 + movdqu 16*4(arg2), %xmm4 + movdqu 16*5(arg2), %xmm5 + movdqu 16*6(arg2), %xmm6 + movdqu 16*7(arg2), %xmm7 + + pshufb %xmm11, %xmm0 + # XOR the initial_crc value + pxor %xmm10, %xmm0 + pshufb %xmm11, %xmm1 + pshufb %xmm11, %xmm2 + pshufb %xmm11, %xmm3 + pshufb %xmm11, %xmm4 + pshufb %xmm11, %xmm5 + pshufb %xmm11, %xmm6 + pshufb %xmm11, %xmm7 + + movdqa rk3(%rip), %xmm10 #xmm10 has rk3 and rk4 + #imm value of pclmulqdq instruction + #will determine which constant to use + + ################################################################# + # we subtract 256 instead of 128 to save one instruction from the loop + sub $256, arg3 + + # at this section of the code, there is 64*x+y (0<=y<64) bytes of + # buffer. The _fold_64_B_loop will fold 64B at a time + # until we have 64+y Bytes of buffer + + + # fold 64B at a time. This section of the code folds 4 xmm + # registers in parallel +_fold_64_B_loop: + + # update the buffer pointer + add $128, arg2 # buf += 64# + + movdqu 16*0(arg2), %xmm9 + movdqu 16*1(arg2), %xmm12 + pshufb %xmm11, %xmm9 + pshufb %xmm11, %xmm12 + movdqa %xmm0, %xmm8 + movdqa %xmm1, %xmm13 + pclmulqdq $0x0 , %xmm10, %xmm0 + pclmulqdq $0x11, %xmm10, %xmm8 + pclmulqdq $0x0 , %xmm10, %xmm1 + pclmulqdq $0x11, %xmm10, %xmm13 + pxor %xmm9 , %xmm0 + xorps %xmm8 , %xmm0 + pxor %xmm12, %xmm1 + xorps %xmm13, %xmm1 + + movdqu 16*2(arg2), %xmm9 + movdqu 16*3(arg2), %xmm12 + pshufb %xmm11, %xmm9 + pshufb %xmm11, %xmm12 + movdqa %xmm2, %xmm8 + movdqa %xmm3, %xmm13 + pclmulqdq $0x0, %xmm10, %xmm2 + pclmulqdq $0x11, %xmm10, %xmm8 + pclmulqdq $0x0, %xmm10, %xmm3 + pclmulqdq $0x11, %xmm10, %xmm13 + pxor %xmm9 , %xmm2 + xorps %xmm8 , %xmm2 + pxor %xmm12, %xmm3 + xorps %xmm13, %xmm3 + + movdqu 16*4(arg2), %xmm9 + movdqu 16*5(arg2), %xmm12 + pshufb %xmm11, %xmm9 + pshufb %xmm11, %xmm12 + movdqa %xmm4, %xmm8 + movdqa %xmm5, %xmm13 + pclmulqdq $0x0, %xmm10, %xmm4 + pclmulqdq $0x11, %xmm10, %xmm8 + pclmulqdq $0x0, %xmm10, %xmm5 + pclmulqdq $0x11, %xmm10, %xmm13 + pxor %xmm9 , %xmm4 + xorps %xmm8 , %xmm4 + pxor %xmm12, %xmm5 + xorps %xmm13, %xmm5 + + movdqu 16*6(arg2), %xmm9 + movdqu 16*7(arg2), %xmm12 + pshufb %xmm11, %xmm9 + pshufb %xmm11, %xmm12 + movdqa %xmm6 , %xmm8 + movdqa %xmm7 , %xmm13 + pclmulqdq $0x0 , %xmm10, %xmm6 + pclmulqdq $0x11, %xmm10, %xmm8 + pclmulqdq $0x0 , %xmm10, %xmm7 + pclmulqdq $0x11, %xmm10, %xmm13 + pxor %xmm9 , %xmm6 + xorps %xmm8 , %xmm6 + pxor %xmm12, %xmm7 + xorps %xmm13, %xmm7 + + sub $128, arg3 + + # check if there is another 64B in the buffer to be able to fold + jge _fold_64_B_loop + ################################################################## + + + add $128, arg2 + # at this point, the buffer pointer is pointing at the last y Bytes + # of the buffer the 64B of folded data is in 4 of the xmm + # registers: xmm0, xmm1, xmm2, xmm3 + + + # fold the 8 xmm registers to 1 xmm register with different constants + + movdqa rk9(%rip), %xmm10 + movdqa %xmm0, %xmm8 + pclmulqdq $0x11, %xmm10, %xmm0 + pclmulqdq $0x0 , %xmm10, %xmm8 + pxor %xmm8, %xmm7 + xorps %xmm0, %xmm7 + + movdqa rk11(%rip), %xmm10 + movdqa %xmm1, %xmm8 + pclmulqdq $0x11, %xmm10, %xmm1 + pclmulqdq $0x0 , %xmm10, %xmm8 + pxor %xmm8, %xmm7 + xorps %xmm1, %xmm7 + + movdqa rk13(%rip), %xmm10 + movdqa %xmm2, %xmm8 + pclmulqdq $0x11, %xmm10, %xmm2 + pclmulqdq $0x0 , %xmm10, %xmm8 + pxor %xmm8, %xmm7 + pxor %xmm2, %xmm7 + + movdqa rk15(%rip), %xmm10 + movdqa %xmm3, %xmm8 + pclmulqdq $0x11, %xmm10, %xmm3 + pclmulqdq $0x0 , %xmm10, %xmm8 + pxor %xmm8, %xmm7 + xorps %xmm3, %xmm7 + + movdqa rk17(%rip), %xmm10 + movdqa %xmm4, %xmm8 + pclmulqdq $0x11, %xmm10, %xmm4 + pclmulqdq $0x0 , %xmm10, %xmm8 + pxor %xmm8, %xmm7 + pxor %xmm4, %xmm7 + + movdqa rk19(%rip), %xmm10 + movdqa %xmm5, %xmm8 + pclmulqdq $0x11, %xmm10, %xmm5 + pclmulqdq $0x0 , %xmm10, %xmm8 + pxor %xmm8, %xmm7 + xorps %xmm5, %xmm7 + + movdqa rk1(%rip), %xmm10 #xmm10 has rk1 and rk2 + #imm value of pclmulqdq instruction + #will determine which constant to use + movdqa %xmm6, %xmm8 + pclmulqdq $0x11, %xmm10, %xmm6 + pclmulqdq $0x0 , %xmm10, %xmm8 + pxor %xmm8, %xmm7 + pxor %xmm6, %xmm7 + + + # instead of 64, we add 48 to the loop counter to save 1 instruction + # from the loop instead of a cmp instruction, we use the negative + # flag with the jl instruction + add $128-16, arg3 + jl _final_reduction_for_128 + + # now we have 16+y bytes left to reduce. 16 Bytes is in register xmm7 + # and the rest is in memory. We can fold 16 bytes at a time if y>=16 + # continue folding 16B at a time + +_16B_reduction_loop: + movdqa %xmm7, %xmm8 + pclmulqdq $0x11, %xmm10, %xmm7 + pclmulqdq $0x0 , %xmm10, %xmm8 + pxor %xmm8, %xmm7 + movdqu (arg2), %xmm0 + pshufb %xmm11, %xmm0 + pxor %xmm0 , %xmm7 + add $16, arg2 + sub $16, arg3 + # instead of a cmp instruction, we utilize the flags with the + # jge instruction equivalent of: cmp arg3, 16-16 + # check if there is any more 16B in the buffer to be able to fold + jge _16B_reduction_loop + + #now we have 16+z bytes left to reduce, where 0<= z < 16. + #first, we reduce the data in the xmm7 register + + +_final_reduction_for_128: + # check if any more data to fold. If not, compute the CRC of + # the final 128 bits + add $16, arg3 + je _128_done + + # here we are getting data that is less than 16 bytes. + # since we know that there was data before the pointer, we can + # offset the input pointer before the actual point, to receive + # exactly 16 bytes. after that the registers need to be adjusted. +_get_last_two_xmms: + movdqa %xmm7, %xmm2 + + movdqu -16(arg2, arg3), %xmm1 + pshufb %xmm11, %xmm1 + + # get rid of the extra data that was loaded before + # load the shift constant + lea pshufb_shf_table+16(%rip), %rax + sub arg3, %rax + movdqu (%rax), %xmm0 + + # shift xmm2 to the left by arg3 bytes + pshufb %xmm0, %xmm2 + + # shift xmm7 to the right by 16-arg3 bytes + pxor mask1(%rip), %xmm0 + pshufb %xmm0, %xmm7 + pblendvb %xmm2, %xmm1 #xmm0 is implicit + + # fold 16 Bytes + movdqa %xmm1, %xmm2 + movdqa %xmm7, %xmm8 + pclmulqdq $0x11, %xmm10, %xmm7 + pclmulqdq $0x0 , %xmm10, %xmm8 + pxor %xmm8, %xmm7 + pxor %xmm2, %xmm7 + +_128_done: + # compute crc of a 128-bit value + movdqa rk5(%rip), %xmm10 # rk5 and rk6 in xmm10 + movdqa %xmm7, %xmm0 + + #64b fold + pclmulqdq $0x1, %xmm10, %xmm7 + pslldq $8 , %xmm0 + pxor %xmm0, %xmm7 + + #32b fold + movdqa %xmm7, %xmm0 + + pand mask2(%rip), %xmm0 + + psrldq $12, %xmm7 + pclmulqdq $0x10, %xmm10, %xmm7 + pxor %xmm0, %xmm7 + + #barrett reduction +_barrett: + movdqa rk7(%rip), %xmm10 # rk7 and rk8 in xmm10 + movdqa %xmm7, %xmm0 + pclmulqdq $0x01, %xmm10, %xmm7 + pslldq $4, %xmm7 + pclmulqdq $0x11, %xmm10, %xmm7 + + pslldq $4, %xmm7 + pxor %xmm0, %xmm7 + pextrd $1, %xmm7, %eax + +_cleanup: + # scale the result back to 16 bits + shr $16, %eax + mov %rcx, %rsp + ret + +######################################################################## + +.align 16 +_less_than_128: + + # check if there is enough buffer to be able to fold 16B at a time + cmp $32, arg3 + jl _less_than_32 + movdqa SHUF_MASK(%rip), %xmm11 + + # now if there is, load the constants + movdqa rk1(%rip), %xmm10 # rk1 and rk2 in xmm10 + + movd arg1_low32, %xmm0 # get the initial crc value + pslldq $12, %xmm0 # align it to its correct place + movdqu (arg2), %xmm7 # load the plaintext + pshufb %xmm11, %xmm7 # byte-reflect the plaintext + pxor %xmm0, %xmm7 + + + # update the buffer pointer + add $16, arg2 + + # update the counter. subtract 32 instead of 16 to save one + # instruction from the loop + sub $32, arg3 + + jmp _16B_reduction_loop + + +.align 16 +_less_than_32: + # mov initial crc to the return value. this is necessary for + # zero-length buffers. + mov arg1_low32, %eax + test arg3, arg3 + je _cleanup + + movdqa SHUF_MASK(%rip), %xmm11 + + movd arg1_low32, %xmm0 # get the initial crc value + pslldq $12, %xmm0 # align it to its correct place + + cmp $16, arg3 + je _exact_16_left + jl _less_than_16_left + + movdqu (arg2), %xmm7 # load the plaintext + pshufb %xmm11, %xmm7 # byte-reflect the plaintext + pxor %xmm0 , %xmm7 # xor the initial crc value + add $16, arg2 + sub $16, arg3 + movdqa rk1(%rip), %xmm10 # rk1 and rk2 in xmm10 + jmp _get_last_two_xmms + + +.align 16 +_less_than_16_left: + # use stack space to load data less than 16 bytes, zero-out + # the 16B in memory first. + + pxor %xmm1, %xmm1 + mov %rsp, %r11 + movdqa %xmm1, (%r11) + + cmp $4, arg3 + jl _only_less_than_4 + + # backup the counter value + mov arg3, %r9 + cmp $8, arg3 + jl _less_than_8_left + + # load 8 Bytes + mov (arg2), %rax + mov %rax, (%r11) + add $8, %r11 + sub $8, arg3 + add $8, arg2 +_less_than_8_left: + + cmp $4, arg3 + jl _less_than_4_left + + # load 4 Bytes + mov (arg2), %eax + mov %eax, (%r11) + add $4, %r11 + sub $4, arg3 + add $4, arg2 +_less_than_4_left: + + cmp $2, arg3 + jl _less_than_2_left + + # load 2 Bytes + mov (arg2), %ax + mov %ax, (%r11) + add $2, %r11 + sub $2, arg3 + add $2, arg2 +_less_than_2_left: + cmp $1, arg3 + jl _zero_left + + # load 1 Byte + mov (arg2), %al + mov %al, (%r11) +_zero_left: + movdqa (%rsp), %xmm7 + pshufb %xmm11, %xmm7 + pxor %xmm0 , %xmm7 # xor the initial crc value + + # shl r9, 4 + lea pshufb_shf_table+16(%rip), %rax + sub %r9, %rax + movdqu (%rax), %xmm0 + pxor mask1(%rip), %xmm0 + + pshufb %xmm0, %xmm7 + jmp _128_done + +.align 16 +_exact_16_left: + movdqu (arg2), %xmm7 + pshufb %xmm11, %xmm7 + pxor %xmm0 , %xmm7 # xor the initial crc value + + jmp _128_done + +_only_less_than_4: + cmp $3, arg3 + jl _only_less_than_3 + + # load 3 Bytes + mov (arg2), %al + mov %al, (%r11) + + mov 1(arg2), %al + mov %al, 1(%r11) + + mov 2(arg2), %al + mov %al, 2(%r11) + + movdqa (%rsp), %xmm7 + pshufb %xmm11, %xmm7 + pxor %xmm0 , %xmm7 # xor the initial crc value + + psrldq $5, %xmm7 + + jmp _barrett +_only_less_than_3: + cmp $2, arg3 + jl _only_less_than_2 + + # load 2 Bytes + mov (arg2), %al + mov %al, (%r11) + + mov 1(arg2), %al + mov %al, 1(%r11) + + movdqa (%rsp), %xmm7 + pshufb %xmm11, %xmm7 + pxor %xmm0 , %xmm7 # xor the initial crc value + + psrldq $6, %xmm7 + + jmp _barrett +_only_less_than_2: + + # load 1 Byte + mov (arg2), %al + mov %al, (%r11) + + movdqa (%rsp), %xmm7 + pshufb %xmm11, %xmm7 + pxor %xmm0 , %xmm7 # xor the initial crc value + + psrldq $7, %xmm7 + + jmp _barrett + +ENDPROC(crc_t10dif_pcl) + +.data + +# precomputed constants +# these constants are precomputed from the poly: +# 0x8bb70000 (0x8bb7 scaled to 32 bits) +.align 16 +# Q = 0x18BB70000 +# rk1 = 2^(32*3) mod Q << 32 +# rk2 = 2^(32*5) mod Q << 32 +# rk3 = 2^(32*15) mod Q << 32 +# rk4 = 2^(32*17) mod Q << 32 +# rk5 = 2^(32*3) mod Q << 32 +# rk6 = 2^(32*2) mod Q << 32 +# rk7 = floor(2^64/Q) +# rk8 = Q +rk1: +.quad 0x2d56000000000000 +rk2: +.quad 0x06df000000000000 +rk3: +.quad 0x9d9d000000000000 +rk4: +.quad 0x7cf5000000000000 +rk5: +.quad 0x2d56000000000000 +rk6: +.quad 0x1368000000000000 +rk7: +.quad 0x00000001f65a57f8 +rk8: +.quad 0x000000018bb70000 + +rk9: +.quad 0xceae000000000000 +rk10: +.quad 0xbfd6000000000000 +rk11: +.quad 0x1e16000000000000 +rk12: +.quad 0x713c000000000000 +rk13: +.quad 0xf7f9000000000000 +rk14: +.quad 0x80a6000000000000 +rk15: +.quad 0x044c000000000000 +rk16: +.quad 0xe658000000000000 +rk17: +.quad 0xad18000000000000 +rk18: +.quad 0xa497000000000000 +rk19: +.quad 0x6ee3000000000000 +rk20: +.quad 0xe7b5000000000000 + + + +mask1: +.octa 0x80808080808080808080808080808080 +mask2: +.octa 0x00000000FFFFFFFFFFFFFFFFFFFFFFFF + +SHUF_MASK: +.octa 0x000102030405060708090A0B0C0D0E0F + +pshufb_shf_table: +# use these values for shift constants for the pshufb instruction +# different alignments result in values as shown: +# DDQ 0x008f8e8d8c8b8a898887868584838281 # shl 15 (16-1) / shr1 +# DDQ 0x01008f8e8d8c8b8a8988878685848382 # shl 14 (16-3) / shr2 +# DDQ 0x0201008f8e8d8c8b8a89888786858483 # shl 13 (16-4) / shr3 +# DDQ 0x030201008f8e8d8c8b8a898887868584 # shl 12 (16-4) / shr4 +# DDQ 0x04030201008f8e8d8c8b8a8988878685 # shl 11 (16-5) / shr5 +# DDQ 0x0504030201008f8e8d8c8b8a89888786 # shl 10 (16-6) / shr6 +# DDQ 0x060504030201008f8e8d8c8b8a898887 # shl 9 (16-7) / shr7 +# DDQ 0x07060504030201008f8e8d8c8b8a8988 # shl 8 (16-8) / shr8 +# DDQ 0x0807060504030201008f8e8d8c8b8a89 # shl 7 (16-9) / shr9 +# DDQ 0x090807060504030201008f8e8d8c8b8a # shl 6 (16-10) / shr10 +# DDQ 0x0a090807060504030201008f8e8d8c8b # shl 5 (16-11) / shr11 +# DDQ 0x0b0a090807060504030201008f8e8d8c # shl 4 (16-12) / shr12 +# DDQ 0x0c0b0a090807060504030201008f8e8d # shl 3 (16-13) / shr13 +# DDQ 0x0d0c0b0a090807060504030201008f8e # shl 2 (16-14) / shr14 +# DDQ 0x0e0d0c0b0a090807060504030201008f # shl 1 (16-15) / shr15 +.octa 0x8f8e8d8c8b8a89888786858483828100 +.octa 0x000e0d0c0b0a09080706050403020100 -- 1.7.11.7 -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
