diff options
Diffstat (limited to 'arch/powerpc/crypto/crct10dif-vpmsum_glue.c')
-rw-r--r-- | arch/powerpc/crypto/crct10dif-vpmsum_glue.c | 126 |
1 files changed, 126 insertions, 0 deletions
diff --git a/arch/powerpc/crypto/crct10dif-vpmsum_glue.c b/arch/powerpc/crypto/crct10dif-vpmsum_glue.c new file mode 100644 index 0000000000..1dc8b69151 --- /dev/null +++ b/arch/powerpc/crypto/crct10dif-vpmsum_glue.c @@ -0,0 +1,126 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Calculate a CRC T10-DIF with vpmsum acceleration + * + * Copyright 2017, Daniel Axtens, IBM Corporation. + * [based on crc32c-vpmsum_glue.c] + */ + +#include <linux/crc-t10dif.h> +#include <crypto/internal/hash.h> +#include <crypto/internal/simd.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/string.h> +#include <linux/kernel.h> +#include <linux/cpufeature.h> +#include <asm/simd.h> +#include <asm/switch_to.h> + +#define VMX_ALIGN 16 +#define VMX_ALIGN_MASK (VMX_ALIGN-1) + +#define VECTOR_BREAKPOINT 64 + +u32 __crct10dif_vpmsum(u32 crc, unsigned char const *p, size_t len); + +static u16 crct10dif_vpmsum(u16 crci, unsigned char const *p, size_t len) +{ + unsigned int prealign; + unsigned int tail; + u32 crc = crci; + + if (len < (VECTOR_BREAKPOINT + VMX_ALIGN) || !crypto_simd_usable()) + return crc_t10dif_generic(crc, p, len); + + if ((unsigned long)p & VMX_ALIGN_MASK) { + prealign = VMX_ALIGN - ((unsigned long)p & VMX_ALIGN_MASK); + crc = crc_t10dif_generic(crc, p, prealign); + len -= prealign; + p += prealign; + } + + if (len & ~VMX_ALIGN_MASK) { + crc <<= 16; + preempt_disable(); + pagefault_disable(); + enable_kernel_altivec(); + crc = __crct10dif_vpmsum(crc, p, len & ~VMX_ALIGN_MASK); + disable_kernel_altivec(); + pagefault_enable(); + preempt_enable(); + crc >>= 16; + } + + tail = len & VMX_ALIGN_MASK; + if (tail) { + p += len & ~VMX_ALIGN_MASK; + crc = crc_t10dif_generic(crc, p, tail); + } + + return crc & 0xffff; +} + +static int crct10dif_vpmsum_init(struct shash_desc *desc) +{ + u16 *crc = shash_desc_ctx(desc); + + *crc = 0; + return 0; +} + +static int crct10dif_vpmsum_update(struct shash_desc *desc, const u8 *data, + unsigned int length) +{ + u16 *crc = shash_desc_ctx(desc); + + *crc = crct10dif_vpmsum(*crc, data, length); + + return 0; +} + + +static int crct10dif_vpmsum_final(struct shash_desc *desc, u8 *out) +{ + u16 *crcp = shash_desc_ctx(desc); + + *(u16 *)out = *crcp; + return 0; +} + +static struct shash_alg alg = { + .init = crct10dif_vpmsum_init, + .update = crct10dif_vpmsum_update, + .final = crct10dif_vpmsum_final, + .descsize = CRC_T10DIF_DIGEST_SIZE, + .digestsize = CRC_T10DIF_DIGEST_SIZE, + .base = { + .cra_name = "crct10dif", + .cra_driver_name = "crct10dif-vpmsum", + .cra_priority = 200, + .cra_blocksize = CRC_T10DIF_BLOCK_SIZE, + .cra_module = THIS_MODULE, + } +}; + +static int __init crct10dif_vpmsum_mod_init(void) +{ + if (!cpu_has_feature(CPU_FTR_ARCH_207S)) + return -ENODEV; + + return crypto_register_shash(&alg); +} + +static void __exit crct10dif_vpmsum_mod_fini(void) +{ + crypto_unregister_shash(&alg); +} + +module_cpu_feature_match(PPC_MODULE_FEATURE_VEC_CRYPTO, crct10dif_vpmsum_mod_init); +module_exit(crct10dif_vpmsum_mod_fini); + +MODULE_AUTHOR("Daniel Axtens <dja@axtens.net>"); +MODULE_DESCRIPTION("CRCT10DIF using vector polynomial multiply-sum instructions"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_CRYPTO("crct10dif"); +MODULE_ALIAS_CRYPTO("crct10dif-vpmsum"); |