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

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Accelerated CRC-T10DIF using ARM NEON and Crypto Extensions instructions
   4 *
   5 * Copyright (C) 2016 Linaro Ltd <ard.biesheuvel@linaro.org>
   6 */
   7
   8#include <linux/crc-t10dif.h>
   9#include <linux/init.h>
  10#include <linux/kernel.h>
  11#include <linux/module.h>
  12#include <linux/string.h>
  13
  14#include <crypto/internal/hash.h>
  15#include <crypto/internal/simd.h>
  16
  17#include <asm/neon.h>
  18#include <asm/simd.h>
  19
  20#define CRC_T10DIF_PMULL_CHUNK_SIZE     16U
  21
  22asmlinkage u16 crc_t10dif_pmull(u16 init_crc, const u8 *buf, size_t len);
  23
  24static int crct10dif_init(struct shash_desc *desc)
  25{
  26        u16 *crc = shash_desc_ctx(desc);
  27
  28        *crc = 0;
  29        return 0;
  30}
  31
  32static int crct10dif_update(struct shash_desc *desc, const u8 *data,
  33                            unsigned int length)
  34{
  35        u16 *crc = shash_desc_ctx(desc);
  36
  37        if (length >= CRC_T10DIF_PMULL_CHUNK_SIZE && crypto_simd_usable()) {
  38                kernel_neon_begin();
  39                *crc = crc_t10dif_pmull(*crc, data, length);
  40                kernel_neon_end();
  41        } else {
  42                *crc = crc_t10dif_generic(*crc, data, length);
  43        }
  44
  45        return 0;
  46}
  47
  48static int crct10dif_final(struct shash_desc *desc, u8 *out)
  49{
  50        u16 *crc = shash_desc_ctx(desc);
  51
  52        *(u16 *)out = *crc;
  53        return 0;
  54}
  55
  56static struct shash_alg crc_t10dif_alg = {
  57        .digestsize             = CRC_T10DIF_DIGEST_SIZE,
  58        .init                   = crct10dif_init,
  59        .update                 = crct10dif_update,
  60        .final                  = crct10dif_final,
  61        .descsize               = CRC_T10DIF_DIGEST_SIZE,
  62
  63        .base.cra_name          = "crct10dif",
  64        .base.cra_driver_name   = "crct10dif-arm-ce",
  65        .base.cra_priority      = 200,
  66        .base.cra_blocksize     = CRC_T10DIF_BLOCK_SIZE,
  67        .base.cra_module        = THIS_MODULE,
  68};
  69
  70static int __init crc_t10dif_mod_init(void)
  71{
  72        if (!(elf_hwcap2 & HWCAP2_PMULL))
  73                return -ENODEV;
  74
  75        return crypto_register_shash(&crc_t10dif_alg);
  76}
  77
  78static void __exit crc_t10dif_mod_exit(void)
  79{
  80        crypto_unregister_shash(&crc_t10dif_alg);
  81}
  82
  83module_init(crc_t10dif_mod_init);
  84module_exit(crc_t10dif_mod_exit);
  85
  86MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
  87MODULE_LICENSE("GPL v2");
  88MODULE_ALIAS_CRYPTO("crct10dif");
  89