LXR linux/arch/arm64/crypto/crct10dif-ce-glue.c

   1/*
   2 * Accelerated CRC-T10DIF using arm64 NEON and Crypto Extensions instructions
   3 *
   4 * Copyright (C) 2016 - 2017 Linaro Ltd <ard.biesheuvel@linaro.org>
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License version 2 as
   8 * published by the Free Software Foundation.
   9 */
  10
  11#include <linux/cpufeature.h>
  12#include <linux/crc-t10dif.h>
  13#include <linux/init.h>
  14#include <linux/kernel.h>
  15#include <linux/module.h>
  16#include <linux/string.h>
  17
  18#include <crypto/internal/hash.h>
  19
  20#include <asm/neon.h>
  21#include <asm/simd.h>
  22
  23#define CRC_T10DIF_PMULL_CHUNK_SIZE     16U
  24
  25asmlinkage u16 crc_t10dif_pmull_p8(u16 init_crc, const u8 *buf, size_t len);
  26asmlinkage u16 crc_t10dif_pmull_p64(u16 init_crc, const u8 *buf, size_t len);
  27
  28static int crct10dif_init(struct shash_desc *desc)
  29{
  30        u16 *crc = shash_desc_ctx(desc);
  31
  32        *crc = 0;
  33        return 0;
  34}
  35
  36static int crct10dif_update_pmull_p8(struct shash_desc *desc, const u8 *data,
  37                            unsigned int length)
  38{
  39        u16 *crc = shash_desc_ctx(desc);
  40
  41        if (length >= CRC_T10DIF_PMULL_CHUNK_SIZE && may_use_simd()) {
  42                kernel_neon_begin();
  43                *crc = crc_t10dif_pmull_p8(*crc, data, length);
  44                kernel_neon_end();
  45        } else {
  46                *crc = crc_t10dif_generic(*crc, data, length);
  47        }
  48
  49        return 0;
  50}
  51
  52static int crct10dif_update_pmull_p64(struct shash_desc *desc, const u8 *data,
  53                            unsigned int length)
  54{
  55        u16 *crc = shash_desc_ctx(desc);
  56
  57        if (length >= CRC_T10DIF_PMULL_CHUNK_SIZE && may_use_simd()) {
  58                kernel_neon_begin();
  59                *crc = crc_t10dif_pmull_p64(*crc, data, length);
  60                kernel_neon_end();
  61        } else {
  62                *crc = crc_t10dif_generic(*crc, data, length);
  63        }
  64
  65        return 0;
  66}
  67
  68static int crct10dif_final(struct shash_desc *desc, u8 *out)
  69{
  70        u16 *crc = shash_desc_ctx(desc);
  71
  72        *(u16 *)out = *crc;
  73        return 0;
  74}
  75
  76static struct shash_alg crc_t10dif_alg[] = {{
  77        .digestsize             = CRC_T10DIF_DIGEST_SIZE,
  78        .init                   = crct10dif_init,
  79        .update                 = crct10dif_update_pmull_p8,
  80        .final                  = crct10dif_final,
  81        .descsize               = CRC_T10DIF_DIGEST_SIZE,
  82
  83        .base.cra_name          = "crct10dif",
  84        .base.cra_driver_name   = "crct10dif-arm64-neon",
  85        .base.cra_priority      = 100,
  86        .base.cra_blocksize     = CRC_T10DIF_BLOCK_SIZE,
  87        .base.cra_module        = THIS_MODULE,
  88}, {
  89        .digestsize             = CRC_T10DIF_DIGEST_SIZE,
  90        .init                   = crct10dif_init,
  91        .update                 = crct10dif_update_pmull_p64,
  92        .final                  = crct10dif_final,
  93        .descsize               = CRC_T10DIF_DIGEST_SIZE,
  94
  95        .base.cra_name          = "crct10dif",
  96        .base.cra_driver_name   = "crct10dif-arm64-ce",
  97        .base.cra_priority      = 200,
  98        .base.cra_blocksize     = CRC_T10DIF_BLOCK_SIZE,
  99        .base.cra_module        = THIS_MODULE,
 100}};
 101
 102static int __init crc_t10dif_mod_init(void)
 103{
 104        if (cpu_have_named_feature(PMULL))
 105                return crypto_register_shashes(crc_t10dif_alg,
 106                                               ARRAY_SIZE(crc_t10dif_alg));
 107        else
 108                /* only register the first array element */
 109                return crypto_register_shash(crc_t10dif_alg);
 110}
 111
 112static void __exit crc_t10dif_mod_exit(void)
 113{
 114        if (cpu_have_named_feature(PMULL))
 115                crypto_unregister_shashes(crc_t10dif_alg,
 116                                          ARRAY_SIZE(crc_t10dif_alg));
 117        else
 118                crypto_unregister_shash(crc_t10dif_alg);
 119}
 120
 121module_cpu_feature_match(ASIMD, crc_t10dif_mod_init);
 122module_exit(crc_t10dif_mod_exit);
 123
 124MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
 125MODULE_LICENSE("GPL v2");
 126MODULE_ALIAS_CRYPTO("crct10dif");
 127MODULE_ALIAS_CRYPTO("crct10dif-arm64-ce");
 128