Ard Biesheuvel | 6ef5737 | 2016-12-05 18:42:25 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Accelerated CRC-T10DIF using arm64 NEON and Crypto Extensions instructions |
| 3 | * |
Ard Biesheuvel | 2dde374 | 2017-07-24 11:28:06 +0100 | [diff] [blame] | 4 | * Copyright (C) 2016 - 2017 Linaro Ltd <ard.biesheuvel@linaro.org> |
Ard Biesheuvel | 6ef5737 | 2016-12-05 18:42:25 +0000 | [diff] [blame] | 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> |
Ard Biesheuvel | 2dde374 | 2017-07-24 11:28:06 +0100 | [diff] [blame] | 21 | #include <asm/simd.h> |
Ard Biesheuvel | 6ef5737 | 2016-12-05 18:42:25 +0000 | [diff] [blame] | 22 | |
| 23 | #define CRC_T10DIF_PMULL_CHUNK_SIZE 16U |
| 24 | |
| 25 | asmlinkage u16 crc_t10dif_pmull(u16 init_crc, const u8 buf[], u64 len); |
| 26 | |
| 27 | static int crct10dif_init(struct shash_desc *desc) |
| 28 | { |
| 29 | u16 *crc = shash_desc_ctx(desc); |
| 30 | |
| 31 | *crc = 0; |
| 32 | return 0; |
| 33 | } |
| 34 | |
| 35 | static int crct10dif_update(struct shash_desc *desc, const u8 *data, |
| 36 | unsigned int length) |
| 37 | { |
| 38 | u16 *crc = shash_desc_ctx(desc); |
| 39 | unsigned int l; |
| 40 | |
| 41 | if (unlikely((u64)data % CRC_T10DIF_PMULL_CHUNK_SIZE)) { |
| 42 | l = min_t(u32, length, CRC_T10DIF_PMULL_CHUNK_SIZE - |
| 43 | ((u64)data % CRC_T10DIF_PMULL_CHUNK_SIZE)); |
| 44 | |
| 45 | *crc = crc_t10dif_generic(*crc, data, l); |
| 46 | |
| 47 | length -= l; |
| 48 | data += l; |
| 49 | } |
| 50 | |
| 51 | if (length > 0) { |
Ard Biesheuvel | 2dde374 | 2017-07-24 11:28:06 +0100 | [diff] [blame] | 52 | if (may_use_simd()) { |
| 53 | kernel_neon_begin(); |
| 54 | *crc = crc_t10dif_pmull(*crc, data, length); |
| 55 | kernel_neon_end(); |
| 56 | } else { |
| 57 | *crc = crc_t10dif_generic(*crc, data, length); |
| 58 | } |
Ard Biesheuvel | 6ef5737 | 2016-12-05 18:42:25 +0000 | [diff] [blame] | 59 | } |
| 60 | |
| 61 | return 0; |
| 62 | } |
| 63 | |
| 64 | static int crct10dif_final(struct shash_desc *desc, u8 *out) |
| 65 | { |
| 66 | u16 *crc = shash_desc_ctx(desc); |
| 67 | |
| 68 | *(u16 *)out = *crc; |
| 69 | return 0; |
| 70 | } |
| 71 | |
| 72 | static struct shash_alg crc_t10dif_alg = { |
| 73 | .digestsize = CRC_T10DIF_DIGEST_SIZE, |
| 74 | .init = crct10dif_init, |
| 75 | .update = crct10dif_update, |
| 76 | .final = crct10dif_final, |
| 77 | .descsize = CRC_T10DIF_DIGEST_SIZE, |
| 78 | |
| 79 | .base.cra_name = "crct10dif", |
| 80 | .base.cra_driver_name = "crct10dif-arm64-ce", |
| 81 | .base.cra_priority = 200, |
| 82 | .base.cra_blocksize = CRC_T10DIF_BLOCK_SIZE, |
| 83 | .base.cra_module = THIS_MODULE, |
| 84 | }; |
| 85 | |
| 86 | static int __init crc_t10dif_mod_init(void) |
| 87 | { |
| 88 | return crypto_register_shash(&crc_t10dif_alg); |
| 89 | } |
| 90 | |
| 91 | static void __exit crc_t10dif_mod_exit(void) |
| 92 | { |
| 93 | crypto_unregister_shash(&crc_t10dif_alg); |
| 94 | } |
| 95 | |
| 96 | module_cpu_feature_match(PMULL, crc_t10dif_mod_init); |
| 97 | module_exit(crc_t10dif_mod_exit); |
| 98 | |
| 99 | MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>"); |
| 100 | MODULE_LICENSE("GPL v2"); |