projects / mirror_ubuntu-artful-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| 6ef5737f AB |
1 | /* |
| 2 | * Accelerated CRC-T10DIF using arm64 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/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 | ||
| 22 | #define CRC_T10DIF_PMULL_CHUNK_SIZE 16U | |
| 23 | ||
| 24 | asmlinkage u16 crc_t10dif_pmull(u16 init_crc, const u8 buf[], u64 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 | unsigned int l; | |
| 39 | ||
| 40 | if (unlikely((u64)data % CRC_T10DIF_PMULL_CHUNK_SIZE)) { | |
| 41 | l = min_t(u32, length, CRC_T10DIF_PMULL_CHUNK_SIZE - | |
| 42 | ((u64)data % CRC_T10DIF_PMULL_CHUNK_SIZE)); | |
| 43 | ||
| 44 | *crc = crc_t10dif_generic(*crc, data, l); | |
| 45 | ||
| 46 | length -= l; | |
| 47 | data += l; | |
| 48 | } | |
| 49 | ||
| 50 | if (length > 0) { | |
| 51 | kernel_neon_begin_partial(14); | |
| 52 | *crc = crc_t10dif_pmull(*crc, data, length); | |
| 53 | kernel_neon_end(); | |
| 54 | } | |
| 55 | ||
| 56 | return 0; | |
| 57 | } | |
| 58 | ||
| 59 | static int crct10dif_final(struct shash_desc *desc, u8 *out) | |
| 60 | { | |
| 61 | u16 *crc = shash_desc_ctx(desc); | |
| 62 | ||
| 63 | *(u16 *)out = *crc; | |
| 64 | return 0; | |
| 65 | } | |
| 66 | ||
| 67 | static struct shash_alg crc_t10dif_alg = { | |
| 68 | .digestsize = CRC_T10DIF_DIGEST_SIZE, | |
| 69 | .init = crct10dif_init, | |
| 70 | .update = crct10dif_update, | |
| 71 | .final = crct10dif_final, | |
| 72 | .descsize = CRC_T10DIF_DIGEST_SIZE, | |
| 73 | ||
| 74 | .base.cra_name = "crct10dif", | |
| 75 | .base.cra_driver_name = "crct10dif-arm64-ce", | |
| 76 | .base.cra_priority = 200, | |
| 77 | .base.cra_blocksize = CRC_T10DIF_BLOCK_SIZE, | |
| 78 | .base.cra_module = THIS_MODULE, | |
| 79 | }; | |
| 80 | ||
| 81 | static int __init crc_t10dif_mod_init(void) | |
| 82 | { | |
| 83 | return crypto_register_shash(&crc_t10dif_alg); | |
| 84 | } | |
| 85 | ||
| 86 | static void __exit crc_t10dif_mod_exit(void) | |
| 87 | { | |
| 88 | crypto_unregister_shash(&crc_t10dif_alg); | |
| 89 | } | |
| 90 | ||
| 91 | module_cpu_feature_match(PMULL, crc_t10dif_mod_init); | |
| 92 | module_exit(crc_t10dif_mod_exit); | |
| 93 | ||
| 94 | MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>"); | |
| 95 | MODULE_LICENSE("GPL v2"); |