| /* |
| * Cryptographic API. |
| * |
| * T10 Data Integrity Field CRC16 Crypto Transform using PCLMULQDQ Instructions |
| * |
| * Copyright (C) 2013 Intel Corporation |
| * Author: Tim Chen <tim.c.chen@linux.intel.com> |
| * |
| * This program is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License as published by the Free |
| * Software Foundation; either version 2 of the License, or (at your option) |
| * any later version. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, |
| * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF |
| * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND |
| * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS |
| * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN |
| * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN |
| * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE |
| * SOFTWARE. |
| * |
| */ |
| |
| #include <linux/types.h> |
| #include <linux/module.h> |
| #include <linux/crc-t10dif.h> |
| #include <crypto/internal/hash.h> |
| #include <linux/init.h> |
| #include <linux/string.h> |
| #include <linux/kernel.h> |
| #include <asm/fpu/api.h> |
| #include <asm/cpufeatures.h> |
| #include <asm/cpu_device_id.h> |
| |
| asmlinkage u16 crc_t10dif_pcl(u16 init_crc, const u8 *buf, size_t len); |
| |
| struct chksum_desc_ctx { |
| __u16 crc; |
| }; |
| |
| static int chksum_init(struct shash_desc *desc) |
| { |
| struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); |
| |
| ctx->crc = 0; |
| |
| return 0; |
| } |
| |
| static int chksum_update(struct shash_desc *desc, const u8 *data, |
| unsigned int length) |
| { |
| struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); |
| |
| if (length >= 16 && irq_fpu_usable()) { |
| kernel_fpu_begin(); |
| ctx->crc = crc_t10dif_pcl(ctx->crc, data, length); |
| kernel_fpu_end(); |
| } else |
| ctx->crc = crc_t10dif_generic(ctx->crc, data, length); |
| return 0; |
| } |
| |
| static int chksum_final(struct shash_desc *desc, u8 *out) |
| { |
| struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); |
| |
| *(__u16 *)out = ctx->crc; |
| return 0; |
| } |
| |
| static int __chksum_finup(__u16 *crcp, const u8 *data, unsigned int len, |
| u8 *out) |
| { |
| if (len >= 16 && irq_fpu_usable()) { |
| kernel_fpu_begin(); |
| *(__u16 *)out = crc_t10dif_pcl(*crcp, data, len); |
| kernel_fpu_end(); |
| } else |
| *(__u16 *)out = crc_t10dif_generic(*crcp, data, len); |
| return 0; |
| } |
| |
| static int chksum_finup(struct shash_desc *desc, const u8 *data, |
| unsigned int len, u8 *out) |
| { |
| struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); |
| |
| return __chksum_finup(&ctx->crc, data, len, out); |
| } |
| |
| static int chksum_digest(struct shash_desc *desc, const u8 *data, |
| unsigned int length, u8 *out) |
| { |
| struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); |
| |
| return __chksum_finup(&ctx->crc, data, length, out); |
| } |
| |
| static struct shash_alg alg = { |
| .digestsize = CRC_T10DIF_DIGEST_SIZE, |
| .init = chksum_init, |
| .update = chksum_update, |
| .final = chksum_final, |
| .finup = chksum_finup, |
| .digest = chksum_digest, |
| .descsize = sizeof(struct chksum_desc_ctx), |
| .base = { |
| .cra_name = "crct10dif", |
| .cra_driver_name = "crct10dif-pclmul", |
| .cra_priority = 200, |
| .cra_blocksize = CRC_T10DIF_BLOCK_SIZE, |
| .cra_module = THIS_MODULE, |
| } |
| }; |
| |
| static const struct x86_cpu_id crct10dif_cpu_id[] = { |
| X86_FEATURE_MATCH(X86_FEATURE_PCLMULQDQ), |
| {} |
| }; |
| MODULE_DEVICE_TABLE(x86cpu, crct10dif_cpu_id); |
| |
| static int __init crct10dif_intel_mod_init(void) |
| { |
| if (!x86_match_cpu(crct10dif_cpu_id)) |
| return -ENODEV; |
| |
| return crypto_register_shash(&alg); |
| } |
| |
| static void __exit crct10dif_intel_mod_fini(void) |
| { |
| crypto_unregister_shash(&alg); |
| } |
| |
| module_init(crct10dif_intel_mod_init); |
| module_exit(crct10dif_intel_mod_fini); |
| |
| MODULE_AUTHOR("Tim Chen <tim.c.chen@linux.intel.com>"); |
| MODULE_DESCRIPTION("T10 DIF CRC calculation accelerated with PCLMULQDQ."); |
| MODULE_LICENSE("GPL"); |
| |
| MODULE_ALIAS_CRYPTO("crct10dif"); |
| MODULE_ALIAS_CRYPTO("crct10dif-pclmul"); |