new file mode 100644
@@ -0,0 +1,53 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * CRC constants generated by:
+ *
+ * ./scripts/gen-crc-consts.py x86_pclmul crc32_lsb_0xedb88320
+ *
+ * Do not edit manually.
+ */
+
+/*
+ * CRC folding constants generated for least-significant-bit-first CRC-32 using
+ * G(x) = x^32 + x^26 + x^23 + x^22 + x^16 + x^12 + x^11 + x^10 + x^8 + x^7 +
+ * x^5 + x^4 + x^2 + x + 1
+ */
+static const struct {
+ u64 fold_across_2048_bits_consts[2];
+ u64 fold_across_1024_bits_consts[2];
+ u64 fold_across_512_bits_consts[2];
+ u64 fold_across_256_bits_consts[2];
+ u64 fold_across_128_bits_consts[2];
+ u8 shuf_table[48];
+ u64 barrett_reduction_consts[2];
+} crc32_lsb_0xedb88320_consts ____cacheline_aligned __maybe_unused = {
+ .fold_across_2048_bits_consts = {
+ 0xce3371cb, /* x^(2048+64-33) mod G(x) */
+ 0xe95c1271, /* x^(2048+0-33) mod G(x) */
+ },
+ .fold_across_1024_bits_consts = {
+ 0x33fff533, /* x^(1024+64-33) mod G(x) */
+ 0x910eeec1, /* x^(1024+0-33) mod G(x) */
+ },
+ .fold_across_512_bits_consts = {
+ 0x8f352d95, /* x^(512+64-33) mod G(x) */
+ 0x1d9513d7, /* x^(512+0-33) mod G(x) */
+ },
+ .fold_across_256_bits_consts = {
+ 0xf1da05aa, /* x^(256+64-33) mod G(x) */
+ 0x81256527, /* x^(256+0-33) mod G(x) */
+ },
+ .fold_across_128_bits_consts = {
+ 0xae689191, /* x^(128+64-33) mod G(x) */
+ 0xccaa009e, /* x^(128+0-33) mod G(x) */
+ },
+ .shuf_table = {
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+ },
+ .barrett_reduction_consts = {
+ 0xb4e5b025f7011641, /* floor(x^95 / G(x)) */
+ 0x1db710641, /* G(x) */
+ },
+};
@@ -5,47 +5,24 @@
* Copyright (C) 2008 Intel Corporation
* Copyright 2012 Xyratex Technology Limited
* Copyright 2024 Google LLC
*/
-#include <asm/cpufeatures.h>
-#include <asm/simd.h>
-#include <crypto/internal/simd.h>
#include <linux/crc32.h>
-#include <linux/linkage.h>
#include <linux/module.h>
-
-/* minimum size of buffer for crc32_pclmul_le_16 */
-#define CRC32_PCLMUL_MIN_LEN 64
+#include "crc-pclmul-template.h"
static DEFINE_STATIC_KEY_FALSE(have_crc32);
static DEFINE_STATIC_KEY_FALSE(have_pclmulqdq);
-u32 crc32_pclmul_le_16(u32 crc, const u8 *buffer, size_t len);
+DECLARE_CRC_PCLMUL_FUNCS(crc32_lsb, u32);
u32 crc32_le_arch(u32 crc, const u8 *p, size_t len)
{
- if (len >= CRC32_PCLMUL_MIN_LEN + 15 &&
- static_branch_likely(&have_pclmulqdq) && crypto_simd_usable()) {
- size_t n = -(uintptr_t)p & 15;
-
- /* align p to 16-byte boundary */
- if (n) {
- crc = crc32_le_base(crc, p, n);
- p += n;
- len -= n;
- }
- n = round_down(len, 16);
- kernel_fpu_begin();
- crc = crc32_pclmul_le_16(crc, p, n);
- kernel_fpu_end();
- p += n;
- len -= n;
- }
- if (len)
- crc = crc32_le_base(crc, p, len);
- return crc;
+ CRC_PCLMUL(crc, p, len, crc32_lsb, crc32_lsb_0xedb88320_consts,
+ have_pclmulqdq);
+ return crc32_le_base(crc, p, len);
}
EXPORT_SYMBOL(crc32_le_arch);
#ifdef CONFIG_X86_64
#define CRC32_INST "crc32q %1, %q0"
@@ -95,12 +72,14 @@ EXPORT_SYMBOL(crc32_be_arch);
static int __init crc32_x86_init(void)
{
if (boot_cpu_has(X86_FEATURE_XMM4_2))
static_branch_enable(&have_crc32);
- if (boot_cpu_has(X86_FEATURE_PCLMULQDQ))
+ if (boot_cpu_has(X86_FEATURE_PCLMULQDQ)) {
static_branch_enable(&have_pclmulqdq);
+ INIT_CRC_PCLMUL(crc32_lsb);
+ }
return 0;
}
arch_initcall(crc32_x86_init);
static void __exit crc32_x86_exit(void)
@@ -1,217 +1,6 @@
-/* SPDX-License-Identifier: GPL-2.0-only */
-/*
- * Copyright 2012 Xyratex Technology Limited
- *
- * Using hardware provided PCLMULQDQ instruction to accelerate the CRC32
- * calculation.
- * CRC32 polynomial:0x04c11db7(BE)/0xEDB88320(LE)
- * PCLMULQDQ is a new instruction in Intel SSE4.2, the reference can be found
- * at:
- * http://www.intel.com/products/processor/manuals/
- * Intel(R) 64 and IA-32 Architectures Software Developer's Manual
- * Volume 2B: Instruction Set Reference, N-Z
- *
- * Authors: Gregory Prestas <Gregory_Prestas@us.xyratex.com>
- * Alexander Boyko <Alexander_Boyko@xyratex.com>
- */
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+// Copyright 2025 Google LLC
-#include <linux/linkage.h>
+#include "crc-pclmul-template.S"
-
-.section .rodata
-.align 16
-/*
- * [x4*128+32 mod P(x) << 32)]' << 1 = 0x154442bd4
- * #define CONSTANT_R1 0x154442bd4LL
- *
- * [(x4*128-32 mod P(x) << 32)]' << 1 = 0x1c6e41596
- * #define CONSTANT_R2 0x1c6e41596LL
- */
-.Lconstant_R2R1:
- .octa 0x00000001c6e415960000000154442bd4
-/*
- * [(x128+32 mod P(x) << 32)]' << 1 = 0x1751997d0
- * #define CONSTANT_R3 0x1751997d0LL
- *
- * [(x128-32 mod P(x) << 32)]' << 1 = 0x0ccaa009e
- * #define CONSTANT_R4 0x0ccaa009eLL
- */
-.Lconstant_R4R3:
- .octa 0x00000000ccaa009e00000001751997d0
-/*
- * [(x64 mod P(x) << 32)]' << 1 = 0x163cd6124
- * #define CONSTANT_R5 0x163cd6124LL
- */
-.Lconstant_R5:
- .octa 0x00000000000000000000000163cd6124
-.Lconstant_mask32:
- .octa 0x000000000000000000000000FFFFFFFF
-/*
- * #define CRCPOLY_TRUE_LE_FULL 0x1DB710641LL
- *
- * Barrett Reduction constant (u64`) = u` = (x**64 / P(x))` = 0x1F7011641LL
- * #define CONSTANT_RU 0x1F7011641LL
- */
-.Lconstant_RUpoly:
- .octa 0x00000001F701164100000001DB710641
-
-#define CONSTANT %xmm0
-
-#ifdef __x86_64__
-#define CRC %edi
-#define BUF %rsi
-#define LEN %rdx
-#else
-#define CRC %eax
-#define BUF %edx
-#define LEN %ecx
-#endif
-
-
-
-.text
-/**
- * Calculate crc32
- * CRC - initial crc32
- * BUF - buffer (16 bytes aligned)
- * LEN - sizeof buffer (16 bytes aligned), LEN should be greater than 63
- * return %eax crc32
- * u32 crc32_pclmul_le_16(u32 crc, const u8 *buffer, size_t len);
- */
-
-SYM_FUNC_START(crc32_pclmul_le_16) /* buffer and buffer size are 16 bytes aligned */
- movdqa (BUF), %xmm1
- movdqa 0x10(BUF), %xmm2
- movdqa 0x20(BUF), %xmm3
- movdqa 0x30(BUF), %xmm4
- movd CRC, CONSTANT
- pxor CONSTANT, %xmm1
- sub $0x40, LEN
- add $0x40, BUF
- cmp $0x40, LEN
- jb .Lless_64
-
-#ifdef __x86_64__
- movdqa .Lconstant_R2R1(%rip), CONSTANT
-#else
- movdqa .Lconstant_R2R1, CONSTANT
-#endif
-
-.Lloop_64:/* 64 bytes Full cache line folding */
- prefetchnta 0x40(BUF)
- movdqa %xmm1, %xmm5
- movdqa %xmm2, %xmm6
- movdqa %xmm3, %xmm7
-#ifdef __x86_64__
- movdqa %xmm4, %xmm8
-#endif
- pclmulqdq $0x00, CONSTANT, %xmm1
- pclmulqdq $0x00, CONSTANT, %xmm2
- pclmulqdq $0x00, CONSTANT, %xmm3
-#ifdef __x86_64__
- pclmulqdq $0x00, CONSTANT, %xmm4
-#endif
- pclmulqdq $0x11, CONSTANT, %xmm5
- pclmulqdq $0x11, CONSTANT, %xmm6
- pclmulqdq $0x11, CONSTANT, %xmm7
-#ifdef __x86_64__
- pclmulqdq $0x11, CONSTANT, %xmm8
-#endif
- pxor %xmm5, %xmm1
- pxor %xmm6, %xmm2
- pxor %xmm7, %xmm3
-#ifdef __x86_64__
- pxor %xmm8, %xmm4
-#else
- /* xmm8 unsupported for x32 */
- movdqa %xmm4, %xmm5
- pclmulqdq $0x00, CONSTANT, %xmm4
- pclmulqdq $0x11, CONSTANT, %xmm5
- pxor %xmm5, %xmm4
-#endif
-
- pxor (BUF), %xmm1
- pxor 0x10(BUF), %xmm2
- pxor 0x20(BUF), %xmm3
- pxor 0x30(BUF), %xmm4
-
- sub $0x40, LEN
- add $0x40, BUF
- cmp $0x40, LEN
- jge .Lloop_64
-.Lless_64:/* Folding cache line into 128bit */
-#ifdef __x86_64__
- movdqa .Lconstant_R4R3(%rip), CONSTANT
-#else
- movdqa .Lconstant_R4R3, CONSTANT
-#endif
- prefetchnta (BUF)
-
- movdqa %xmm1, %xmm5
- pclmulqdq $0x00, CONSTANT, %xmm1
- pclmulqdq $0x11, CONSTANT, %xmm5
- pxor %xmm5, %xmm1
- pxor %xmm2, %xmm1
-
- movdqa %xmm1, %xmm5
- pclmulqdq $0x00, CONSTANT, %xmm1
- pclmulqdq $0x11, CONSTANT, %xmm5
- pxor %xmm5, %xmm1
- pxor %xmm3, %xmm1
-
- movdqa %xmm1, %xmm5
- pclmulqdq $0x00, CONSTANT, %xmm1
- pclmulqdq $0x11, CONSTANT, %xmm5
- pxor %xmm5, %xmm1
- pxor %xmm4, %xmm1
-
- cmp $0x10, LEN
- jb .Lfold_64
-.Lloop_16:/* Folding rest buffer into 128bit */
- movdqa %xmm1, %xmm5
- pclmulqdq $0x00, CONSTANT, %xmm1
- pclmulqdq $0x11, CONSTANT, %xmm5
- pxor %xmm5, %xmm1
- pxor (BUF), %xmm1
- sub $0x10, LEN
- add $0x10, BUF
- cmp $0x10, LEN
- jge .Lloop_16
-
-.Lfold_64:
- /* perform the last 64 bit fold, also adds 32 zeroes
- * to the input stream */
- pclmulqdq $0x01, %xmm1, CONSTANT /* R4 * xmm1.low */
- psrldq $0x08, %xmm1
- pxor CONSTANT, %xmm1
-
- /* final 32-bit fold */
- movdqa %xmm1, %xmm2
-#ifdef __x86_64__
- movdqa .Lconstant_R5(%rip), CONSTANT
- movdqa .Lconstant_mask32(%rip), %xmm3
-#else
- movdqa .Lconstant_R5, CONSTANT
- movdqa .Lconstant_mask32, %xmm3
-#endif
- psrldq $0x04, %xmm2
- pand %xmm3, %xmm1
- pclmulqdq $0x00, CONSTANT, %xmm1
- pxor %xmm2, %xmm1
-
- /* Finish up with the bit-reversed barrett reduction 64 ==> 32 bits */
-#ifdef __x86_64__
- movdqa .Lconstant_RUpoly(%rip), CONSTANT
-#else
- movdqa .Lconstant_RUpoly, CONSTANT
-#endif
- movdqa %xmm1, %xmm2
- pand %xmm3, %xmm1
- pclmulqdq $0x10, CONSTANT, %xmm1
- pand %xmm3, %xmm1
- pclmulqdq $0x00, CONSTANT, %xmm1
- pxor %xmm2, %xmm1
- pextrd $0x01, %xmm1, %eax
-
- RET
-SYM_FUNC_END(crc32_pclmul_le_16)
+DEFINE_CRC_PCLMUL_FUNCS(crc32_lsb, /* bits= */ 32, /* lsb= */ 1)