lib/crc: x86: Migrate optimized CRC code into lib/crc/

Move the x86-optimized CRC code from arch/x86/lib/crc* into its new
location in lib/crc/x86/, and wire it up in the new way.  This new way
of organizing the CRC code eliminates the need to artificially split the
code for each CRC variant into separate arch and generic modules,
enabling better inlining and dead code elimination.  For more details,
see "lib/crc: Prepare for arch-optimized code in subdirs of lib/crc/".

Reviewed-by: "Martin K. Petersen" <martin.petersen@oracle.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: "Jason A. Donenfeld" <Jason@zx2c4.com>
Link: https://lore.kernel.org/r/20250607200454.73587-12-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>

arch/x86/Kconfig

@@ -79,9 +79,6 @@ config X86
 	select ARCH_HAS_CPU_CACHE_INVALIDATE_MEMREGION
 	select ARCH_HAS_CPU_FINALIZE_INIT
 	select ARCH_HAS_CPU_PASID		if IOMMU_SVA
-	select ARCH_HAS_CRC32
-	select ARCH_HAS_CRC64			if X86_64
-	select ARCH_HAS_CRC_T10DIF
 	select ARCH_HAS_CURRENT_STACK_POINTER
 	select ARCH_HAS_DEBUG_VIRTUAL
 	select ARCH_HAS_DEBUG_VM_PGTABLE	if !X86_PAE

arch/x86/lib/Makefile

@@ -40,16 +40,6 @@ lib-$(CONFIG_RANDOMIZE_BASE) += kaslr.o
 lib-$(CONFIG_FUNCTION_ERROR_INJECTION)	+= error-inject.o
 lib-$(CONFIG_MITIGATION_RETPOLINE) += retpoline.o
 
-obj-$(CONFIG_CRC32_ARCH) += crc32-x86.o
-crc32-x86-y := crc32.o crc32-pclmul.o
-crc32-x86-$(CONFIG_64BIT) += crc32c-3way.o
-
-obj-$(CONFIG_CRC64_ARCH) += crc64-x86.o
-crc64-x86-y := crc64.o crc64-pclmul.o
-
-obj-$(CONFIG_CRC_T10DIF_ARCH) += crc-t10dif-x86.o
-crc-t10dif-x86-y := crc-t10dif.o crc16-msb-pclmul.o
-
 obj-y += msr.o msr-reg.o msr-reg-export.o hweight.o
 obj-y += iomem.o
 

lib/crc/Kconfig

@@ -54,6 +54,7 @@ config CRC_T10DIF_ARCH
 	default y if ARM64 && KERNEL_MODE_NEON
 	default y if PPC64 && ALTIVEC
 	default y if RISCV && RISCV_ISA_ZBC
+	default y if X86
 
 config CRC32
 	tristate
@@ -76,6 +77,7 @@ config CRC32_ARCH
 	default y if RISCV && RISCV_ISA_ZBC
 	default y if S390
 	default y if SPARC64
+	default y if X86
 
 config CRC64
 	tristate
@@ -90,6 +92,7 @@ config CRC64_ARCH
 	bool
 	depends on CRC64 && CRC_OPTIMIZATIONS
 	default y if RISCV && RISCV_ISA_ZBC && 64BIT
+	default y if X86_64
 
 config CRC_OPTIMIZATIONS
 	bool "Enable optimized CRC implementations" if EXPERT

lib/crc/Makefile

@@ -17,6 +17,7 @@ crc-t10dif-$(CONFIG_ARM) += arm/crc-t10dif-core.o
 crc-t10dif-$(CONFIG_ARM64) += arm64/crc-t10dif-core.o
 crc-t10dif-$(CONFIG_PPC) += powerpc/crct10dif-vpmsum_asm.o
 crc-t10dif-$(CONFIG_RISCV) += riscv/crc16_msb.o
+crc-t10dif-$(CONFIG_X86) += x86/crc16-msb-pclmul.o
 endif
 
 obj-$(CONFIG_CRC32) += crc32.o
@@ -29,6 +30,8 @@ crc32-$(CONFIG_PPC) += powerpc/crc32c-vpmsum_asm.o
 crc32-$(CONFIG_RISCV) += riscv/crc32_lsb.o riscv/crc32_msb.o
 crc32-$(CONFIG_S390) += s390/crc32le-vx.o s390/crc32be-vx.o
 crc32-$(CONFIG_SPARC) += sparc/crc32c_asm.o
+crc32-$(CONFIG_X86) += x86/crc32-pclmul.o
+crc32-$(CONFIG_X86_64) += x86/crc32c-3way.o
 endif
 
 obj-$(CONFIG_CRC64) += crc64.o
@@ -36,6 +39,7 @@ crc64-y := crc64-main.o
 ifeq ($(CONFIG_CRC64_ARCH),y)
 CFLAGS_crc64-main.o += -I$(src)/$(SRCARCH)
 crc64-$(CONFIG_RISCV) += riscv/crc64_lsb.o riscv/crc64_msb.o
+crc64-$(CONFIG_X86) += x86/crc64-pclmul.o
 endif
 
 obj-y += tests/

lib/crc/x86/crc-t10dif.h

@@ -5,36 +5,24 @@
  * Copyright 2024 Google LLC
  */
 
-#include <linux/crc-t10dif.h>
-#include <linux/module.h>
 #include "crc-pclmul-template.h"
 
 static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_pclmulqdq);
 
 DECLARE_CRC_PCLMUL_FUNCS(crc16_msb, u16);
 
-u16 crc_t10dif_arch(u16 crc, const u8 *p, size_t len)
+static inline u16 crc_t10dif_arch(u16 crc, const u8 *p, size_t len)
 {
 	CRC_PCLMUL(crc, p, len, crc16_msb, crc16_msb_0x8bb7_consts,
 		   have_pclmulqdq);
 	return crc_t10dif_generic(crc, p, len);
 }
-EXPORT_SYMBOL(crc_t10dif_arch);
 
-static int __init crc_t10dif_x86_init(void)
+#define crc_t10dif_mod_init_arch crc_t10dif_mod_init_arch
+static inline void crc_t10dif_mod_init_arch(void)
 {
 	if (boot_cpu_has(X86_FEATURE_PCLMULQDQ)) {
 		static_branch_enable(&have_pclmulqdq);
 		INIT_CRC_PCLMUL(crc16_msb);
 	}
-	return 0;
 }
-subsys_initcall(crc_t10dif_x86_init);
-
-static void __exit crc_t10dif_x86_exit(void)
-{
-}
-module_exit(crc_t10dif_x86_exit);
-
-MODULE_DESCRIPTION("CRC-T10DIF using [V]PCLMULQDQ instructions");
-MODULE_LICENSE("GPL");

lib/crc/x86/crc32.h

@@ -7,8 +7,6 @@
  * Copyright 2024 Google LLC
  */
 
-#include <linux/crc32.h>
-#include <linux/module.h>
 #include "crc-pclmul-template.h"
 
 static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_crc32);
@@ -16,13 +14,12 @@ static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_pclmulqdq);
 
 DECLARE_CRC_PCLMUL_FUNCS(crc32_lsb, u32);
 
-u32 crc32_le_arch(u32 crc, const u8 *p, size_t len)
+static inline u32 crc32_le_arch(u32 crc, const u8 *p, size_t len)
 {
 	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"
@@ -38,7 +35,7 @@ EXPORT_SYMBOL(crc32_le_arch);
 
 asmlinkage u32 crc32c_x86_3way(u32 crc, const u8 *buffer, size_t len);
 
-u32 crc32c_arch(u32 crc, const u8 *p, size_t len)
+static inline u32 crc32c_arch(u32 crc, const u8 *p, size_t len)
 {
 	size_t num_longs;
 
@@ -70,15 +67,11 @@ u32 crc32c_arch(u32 crc, const u8 *p, size_t len)
 
 	return crc;
 }
-EXPORT_SYMBOL(crc32c_arch);
 
-u32 crc32_be_arch(u32 crc, const u8 *p, size_t len)
+#define crc32_be_arch crc32_be_base /* not implemented on this arch */
-{
-	return crc32_be_base(crc, p, len);
-}
-EXPORT_SYMBOL(crc32_be_arch);
 
-static int __init crc32_x86_init(void)
+#define crc32_mod_init_arch crc32_mod_init_arch
+static inline void crc32_mod_init_arch(void)
 {
 	if (boot_cpu_has(X86_FEATURE_XMM4_2))
 		static_branch_enable(&have_crc32);
@@ -86,16 +79,9 @@ static int __init crc32_x86_init(void)
 		static_branch_enable(&have_pclmulqdq);
 		INIT_CRC_PCLMUL(crc32_lsb);
 	}
-	return 0;
 }
-subsys_initcall(crc32_x86_init);
 
-static void __exit crc32_x86_exit(void)
+static inline u32 crc32_optimizations_arch(void)
-{
-}
-module_exit(crc32_x86_exit);
-
-u32 crc32_optimizations(void)
 {
 	u32 optimizations = 0;
 
@@ -105,7 +91,3 @@ u32 crc32_optimizations(void)
 		optimizations |= CRC32_LE_OPTIMIZATION;
 	return optimizations;
 }
-EXPORT_SYMBOL(crc32_optimizations);
-
-MODULE_DESCRIPTION("x86-optimized CRC32 functions");
-MODULE_LICENSE("GPL");

lib/crc/x86/crc64.h

@@ -5,8 +5,6 @@
  * Copyright 2025 Google LLC
  */
 
-#include <linux/crc64.h>
-#include <linux/module.h>
 #include "crc-pclmul-template.h"
 
 static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_pclmulqdq);
@@ -14,37 +12,26 @@ static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_pclmulqdq);
 DECLARE_CRC_PCLMUL_FUNCS(crc64_msb, u64);
 DECLARE_CRC_PCLMUL_FUNCS(crc64_lsb, u64);
 
-u64 crc64_be_arch(u64 crc, const u8 *p, size_t len)
+static inline u64 crc64_be_arch(u64 crc, const u8 *p, size_t len)
 {
 	CRC_PCLMUL(crc, p, len, crc64_msb, crc64_msb_0x42f0e1eba9ea3693_consts,
 		   have_pclmulqdq);
 	return crc64_be_generic(crc, p, len);
 }
-EXPORT_SYMBOL_GPL(crc64_be_arch);
 
-u64 crc64_nvme_arch(u64 crc, const u8 *p, size_t len)
+static inline u64 crc64_nvme_arch(u64 crc, const u8 *p, size_t len)
 {
 	CRC_PCLMUL(crc, p, len, crc64_lsb, crc64_lsb_0x9a6c9329ac4bc9b5_consts,
 		   have_pclmulqdq);
 	return crc64_nvme_generic(crc, p, len);
 }
-EXPORT_SYMBOL_GPL(crc64_nvme_arch);
 
-static int __init crc64_x86_init(void)
+#define crc64_mod_init_arch crc64_mod_init_arch
+static inline void crc64_mod_init_arch(void)
 {
 	if (boot_cpu_has(X86_FEATURE_PCLMULQDQ)) {
 		static_branch_enable(&have_pclmulqdq);
 		INIT_CRC_PCLMUL(crc64_msb);
 		INIT_CRC_PCLMUL(crc64_lsb);
 	}
-	return 0;
 }
-subsys_initcall(crc64_x86_init);
-
-static void __exit crc64_x86_exit(void)
-{
-}
-module_exit(crc64_x86_exit);
-
-MODULE_DESCRIPTION("CRC64 using [V]PCLMULQDQ instructions");
-MODULE_LICENSE("GPL");