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
  22 asmlinkage u16 crc_t10dif_pmull64(u16 init_crc, const u8 *buf, size_t len);
  23 asmlinkage void crc_t10dif_pmull8(u16 init_crc, const u8 *buf, size_t len,
  24                                   u8 out[16]);
  25
  26 static int crct10dif_init(struct shash_desc *desc)
  27 {
  28         u16 *crc = shash_desc_ctx(desc);
  29
  30         *crc = 0;
  31         return 0;
  32 }
  33
  34 static int crct10dif_update_ce(struct shash_desc *desc, const u8 *data,
  35                                unsigned int length)
  36 {
  37         u16 *crc = shash_desc_ctx(desc);
  38
  39         if (length >= CRC_T10DIF_PMULL_CHUNK_SIZE && crypto_simd_usable()) {
  40                 kernel_neon_begin();
  41                 *crc = crc_t10dif_pmull64(*crc, data, length);
  42                 kernel_neon_end();
  43         } else {
  44                 *crc = crc_t10dif_generic(*crc, data, length);
  45         }
  46
  47         return 0;
  48 }
  49
  50 static int crct10dif_update_neon(struct shash_desc *desc, const u8 *data,
  51                                  unsigned int length)
  52 {
  53         u16 *crcp = shash_desc_ctx(desc);
  54         u8 buf[16] __aligned(16);
  55         u16 crc = *crcp;
  56
  57         if (length > CRC_T10DIF_PMULL_CHUNK_SIZE && crypto_simd_usable()) {
  58                 kernel_neon_begin();
  59                 crc_t10dif_pmull8(crc, data, length, buf);
  60                 kernel_neon_end();
  61
  62                 crc = 0;
  63                 data = buf;
  64                 length = sizeof(buf);
  65         }
  66
  67         *crcp = crc_t10dif_generic(crc, data, length);
  68         return 0;
  69 }
  70
  71 static int crct10dif_final(struct shash_desc *desc, u8 *out)
  72 {
  73         u16 *crc = shash_desc_ctx(desc);
  74
  75         *(u16 *)out = *crc;
  76         return 0;
  77 }
  78
  79 static struct shash_alg algs[] = {{
  80         .digestsize             = CRC_T10DIF_DIGEST_SIZE,
  81         .init                   = crct10dif_init,
  82         .update                 = crct10dif_update_neon,
  83         .final                  = crct10dif_final,
  84         .descsize               = CRC_T10DIF_DIGEST_SIZE,
  85
  86         .base.cra_name          = "crct10dif",
  87         .base.cra_driver_name   = "crct10dif-arm-neon",
  88         .base.cra_priority      = 150,
  89         .base.cra_blocksize     = CRC_T10DIF_BLOCK_SIZE,
  90         .base.cra_module        = THIS_MODULE,
  91 }, {
  92         .digestsize             = CRC_T10DIF_DIGEST_SIZE,
  93         .init                   = crct10dif_init,
  94         .update                 = crct10dif_update_ce,
  95         .final                  = crct10dif_final,
  96         .descsize               = CRC_T10DIF_DIGEST_SIZE,
  97
  98         .base.cra_name          = "crct10dif",
  99         .base.cra_driver_name   = "crct10dif-arm-ce",
 100         .base.cra_priority      = 200,
 101         .base.cra_blocksize     = CRC_T10DIF_BLOCK_SIZE,
 102         .base.cra_module        = THIS_MODULE,
 103 }};
 104
 105 static int __init crc_t10dif_mod_init(void)
 106 {
 107         if (!(elf_hwcap & HWCAP_NEON))
 108                 return -ENODEV;
 109
 110         return crypto_register_shashes(algs, 1 + !!(elf_hwcap2 & HWCAP2_PMULL));
 111 }
 112
 113 static void __exit crc_t10dif_mod_exit(void)
 114 {
 115         crypto_unregister_shashes(algs, 1 + !!(elf_hwcap2 & HWCAP2_PMULL));
 116 }
 117
 118 module_init(crc_t10dif_mod_init);
 119 module_exit(crc_t10dif_mod_exit);
 120
 121 MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
 122 MODULE_DESCRIPTION("Accelerated CRC-T10DIF using ARM NEON and Crypto Extensions");
 123 MODULE_LICENSE("GPL v2");
 124 MODULE_ALIAS_CRYPTO("crct10dif");