| rjw | 1f88458 | 2022-01-06 17:20:42 +0800 | [diff] [blame^] | 1 | /* |
| 2 | * Accelerated CRC-T10DIF using ARM NEON and Crypto Extensions instructions |
| 3 | * |
| 4 | * Copyright (C) 2016 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/crc-t10dif.h> |
| 12 | #include <linux/init.h> |
| 13 | #include <linux/kernel.h> |
| 14 | #include <linux/module.h> |
| 15 | #include <linux/string.h> |
| 16 | |
| 17 | #include <crypto/internal/hash.h> |
| 18 | |
| 19 | #include <asm/neon.h> |
| 20 | #include <asm/simd.h> |
| 21 | |
| 22 | #define CRC_T10DIF_PMULL_CHUNK_SIZE 16U |
| 23 | |
| 24 | asmlinkage u16 crc_t10dif_pmull(u16 init_crc, const u8 buf[], u32 len); |
| 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(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 && may_use_simd()) { |
| 40 | kernel_neon_begin(); |
| 41 | *crc = crc_t10dif_pmull(*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_final(struct shash_desc *desc, u8 *out) |
| 51 | { |
| 52 | u16 *crc = shash_desc_ctx(desc); |
| 53 | |
| 54 | *(u16 *)out = *crc; |
| 55 | return 0; |
| 56 | } |
| 57 | |
| 58 | static struct shash_alg crc_t10dif_alg = { |
| 59 | .digestsize = CRC_T10DIF_DIGEST_SIZE, |
| 60 | .init = crct10dif_init, |
| 61 | .update = crct10dif_update, |
| 62 | .final = crct10dif_final, |
| 63 | .descsize = CRC_T10DIF_DIGEST_SIZE, |
| 64 | |
| 65 | .base.cra_name = "crct10dif", |
| 66 | .base.cra_driver_name = "crct10dif-arm-ce", |
| 67 | .base.cra_priority = 200, |
| 68 | .base.cra_blocksize = CRC_T10DIF_BLOCK_SIZE, |
| 69 | .base.cra_module = THIS_MODULE, |
| 70 | }; |
| 71 | |
| 72 | static int __init crc_t10dif_mod_init(void) |
| 73 | { |
| 74 | if (!(elf_hwcap2 & HWCAP2_PMULL)) |
| 75 | return -ENODEV; |
| 76 | |
| 77 | return crypto_register_shash(&crc_t10dif_alg); |
| 78 | } |
| 79 | |
| 80 | static void __exit crc_t10dif_mod_exit(void) |
| 81 | { |
| 82 | crypto_unregister_shash(&crc_t10dif_alg); |
| 83 | } |
| 84 | |
| 85 | module_init(crc_t10dif_mod_init); |
| 86 | module_exit(crc_t10dif_mod_exit); |
| 87 | |
| 88 | MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>"); |
| 89 | MODULE_LICENSE("GPL v2"); |
| 90 | MODULE_ALIAS_CRYPTO("crct10dif"); |