diff options
Diffstat (limited to 'arch/powerpc/crypto/crc32c-vpmsum_glue.c')
-rw-r--r-- | arch/powerpc/crypto/crc32c-vpmsum_glue.c | 173 |
1 files changed, 173 insertions, 0 deletions
diff --git a/arch/powerpc/crypto/crc32c-vpmsum_glue.c b/arch/powerpc/crypto/crc32c-vpmsum_glue.c new file mode 100644 index 0000000000..63760b7dbb --- /dev/null +++ b/arch/powerpc/crypto/crc32c-vpmsum_glue.c @@ -0,0 +1,173 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include <linux/crc32.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 CHKSUM_BLOCK_SIZE 1 +#define CHKSUM_DIGEST_SIZE 4 + +#define VMX_ALIGN 16 +#define VMX_ALIGN_MASK (VMX_ALIGN-1) + +#define VECTOR_BREAKPOINT 512 + +u32 __crc32c_vpmsum(u32 crc, unsigned char const *p, size_t len); + +static u32 crc32c_vpmsum(u32 crc, unsigned char const *p, size_t len) +{ + unsigned int prealign; + unsigned int tail; + + if (len < (VECTOR_BREAKPOINT + VMX_ALIGN) || !crypto_simd_usable()) + return __crc32c_le(crc, p, len); + + if ((unsigned long)p & VMX_ALIGN_MASK) { + prealign = VMX_ALIGN - ((unsigned long)p & VMX_ALIGN_MASK); + crc = __crc32c_le(crc, p, prealign); + len -= prealign; + p += prealign; + } + + if (len & ~VMX_ALIGN_MASK) { + preempt_disable(); + pagefault_disable(); + enable_kernel_altivec(); + crc = __crc32c_vpmsum(crc, p, len & ~VMX_ALIGN_MASK); + disable_kernel_altivec(); + pagefault_enable(); + preempt_enable(); + } + + tail = len & VMX_ALIGN_MASK; + if (tail) { + p += len & ~VMX_ALIGN_MASK; + crc = __crc32c_le(crc, p, tail); + } + + return crc; +} + +static int crc32c_vpmsum_cra_init(struct crypto_tfm *tfm) +{ + u32 *key = crypto_tfm_ctx(tfm); + + *key = ~0; + + return 0; +} + +/* + * Setting the seed allows arbitrary accumulators and flexible XOR policy + * If your algorithm starts with ~0, then XOR with ~0 before you set + * the seed. + */ +static int crc32c_vpmsum_setkey(struct crypto_shash *hash, const u8 *key, + unsigned int keylen) +{ + u32 *mctx = crypto_shash_ctx(hash); + + if (keylen != sizeof(u32)) + return -EINVAL; + *mctx = le32_to_cpup((__le32 *)key); + return 0; +} + +static int crc32c_vpmsum_init(struct shash_desc *desc) +{ + u32 *mctx = crypto_shash_ctx(desc->tfm); + u32 *crcp = shash_desc_ctx(desc); + + *crcp = *mctx; + + return 0; +} + +static int crc32c_vpmsum_update(struct shash_desc *desc, const u8 *data, + unsigned int len) +{ + u32 *crcp = shash_desc_ctx(desc); + + *crcp = crc32c_vpmsum(*crcp, data, len); + + return 0; +} + +static int __crc32c_vpmsum_finup(u32 *crcp, const u8 *data, unsigned int len, + u8 *out) +{ + *(__le32 *)out = ~cpu_to_le32(crc32c_vpmsum(*crcp, data, len)); + + return 0; +} + +static int crc32c_vpmsum_finup(struct shash_desc *desc, const u8 *data, + unsigned int len, u8 *out) +{ + return __crc32c_vpmsum_finup(shash_desc_ctx(desc), data, len, out); +} + +static int crc32c_vpmsum_final(struct shash_desc *desc, u8 *out) +{ + u32 *crcp = shash_desc_ctx(desc); + + *(__le32 *)out = ~cpu_to_le32p(crcp); + + return 0; +} + +static int crc32c_vpmsum_digest(struct shash_desc *desc, const u8 *data, + unsigned int len, u8 *out) +{ + return __crc32c_vpmsum_finup(crypto_shash_ctx(desc->tfm), data, len, + out); +} + +static struct shash_alg alg = { + .setkey = crc32c_vpmsum_setkey, + .init = crc32c_vpmsum_init, + .update = crc32c_vpmsum_update, + .final = crc32c_vpmsum_final, + .finup = crc32c_vpmsum_finup, + .digest = crc32c_vpmsum_digest, + .descsize = sizeof(u32), + .digestsize = CHKSUM_DIGEST_SIZE, + .base = { + .cra_name = "crc32c", + .cra_driver_name = "crc32c-vpmsum", + .cra_priority = 200, + .cra_flags = CRYPTO_ALG_OPTIONAL_KEY, + .cra_blocksize = CHKSUM_BLOCK_SIZE, + .cra_ctxsize = sizeof(u32), + .cra_module = THIS_MODULE, + .cra_init = crc32c_vpmsum_cra_init, + } +}; + +static int __init crc32c_vpmsum_mod_init(void) +{ + if (!cpu_has_feature(CPU_FTR_ARCH_207S)) + return -ENODEV; + + return crypto_register_shash(&alg); +} + +static void __exit crc32c_vpmsum_mod_fini(void) +{ + crypto_unregister_shash(&alg); +} + +module_cpu_feature_match(PPC_MODULE_FEATURE_VEC_CRYPTO, crc32c_vpmsum_mod_init); +module_exit(crc32c_vpmsum_mod_fini); + +MODULE_AUTHOR("Anton Blanchard <anton@samba.org>"); +MODULE_DESCRIPTION("CRC32C using vector polynomial multiply-sum instructions"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_CRYPTO("crc32c"); +MODULE_ALIAS_CRYPTO("crc32c-vpmsum"); |