loongarch/crc32: expose CRC32 functions through lib

Move the loongarch CRC32 assembly code into the lib directory and wire
it up to the library interface.  This allows it to be used without going
through the crypto API.  It remains usable via the crypto API too via
the shash algorithms that use the library interface.  Thus all the
arch-specific "shash" code becomes unnecessary and is removed.

Note: to see the diff from arch/loongarch/crypto/crc32-loongarch.c to
arch/loongarch/lib/crc32-loongarch.c, view this commit with
'git show -M10'.

Reviewed-by: Ard Biesheuvel <[email protected]>
Reviewed-by: WangYuli <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Eric Biggers <[email protected]>

Author: ebiggers

arch/loongarch/Kconfig

@@ -15,6 +15,7 @@ config LOONGARCH
 	select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE
 	select ARCH_HAS_ACPI_TABLE_UPGRADE	if ACPI
 	select ARCH_HAS_CPU_FINALIZE_INIT
+	select ARCH_HAS_CRC32
 	select ARCH_HAS_CURRENT_STACK_POINTER
 	select ARCH_HAS_DEBUG_VM_PGTABLE
 	select ARCH_HAS_FAST_MULTIPLIER

arch/loongarch/configs/loongson3_defconfig

@@ -1040,7 +1040,6 @@ CONFIG_CRYPTO_USER_API_HASH=m
 CONFIG_CRYPTO_USER_API_SKCIPHER=m
 CONFIG_CRYPTO_USER_API_RNG=m
 CONFIG_CRYPTO_USER_API_AEAD=m
-CONFIG_CRYPTO_CRC32_LOONGARCH=m
 CONFIG_CRYPTO_DEV_VIRTIO=m
 CONFIG_DMA_CMA=y
 CONFIG_DMA_NUMA_CMA=y

arch/loongarch/crypto/Kconfig

@@ -2,13 +2,4 @@
 
 menu "Accelerated Cryptographic Algorithms for CPU (loongarch)"
 
-config CRYPTO_CRC32_LOONGARCH
-	tristate "CRC32c and CRC32"
-	select CRC32
-	select CRYPTO_HASH
-	help
-	  CRC32c and CRC32 CRC algorithms
-
-	  Architecture: LoongArch with CRC32 instructions
-
 endmenu

arch/loongarch/crypto/Makefile

@@ -2,5 +2,3 @@
 #
 # Makefile for LoongArch crypto files..
 #
-
-obj-$(CONFIG_CRYPTO_CRC32_LOONGARCH) += crc32-loongarch.o

arch/loongarch/crypto/crc32-loongarch.c

@@ -11,3 +11,5 @@ obj-$(CONFIG_ARCH_SUPPORTS_INT128) += tishift.o
 obj-$(CONFIG_CPU_HAS_LSX) += xor_simd.o xor_simd_glue.o
 
 obj-$(CONFIG_FUNCTION_ERROR_INJECTION) += error-inject.o
+
+obj-$(CONFIG_CRC32_ARCH) += crc32-loongarch.o