91 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			91 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Accelerated CRC-T10DIF using ARM NEON and Crypto Extensions instructions
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|  *
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|  * Copyright (C) 2016 Linaro Ltd <ard.biesheuvel@linaro.org>
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|  *
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|  * This program is free software; you can redistribute it and/or modify
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|  * it under the terms of the GNU General Public License version 2 as
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|  * published by the Free Software Foundation.
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|  */
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| 
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| #include <linux/crc-t10dif.h>
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| #include <linux/init.h>
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| #include <linux/kernel.h>
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| #include <linux/module.h>
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| #include <linux/string.h>
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| 
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| #include <crypto/internal/hash.h>
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| 
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| #include <asm/neon.h>
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| #include <asm/simd.h>
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| 
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| #define CRC_T10DIF_PMULL_CHUNK_SIZE	16U
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| 
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| asmlinkage u16 crc_t10dif_pmull(u16 init_crc, const u8 buf[], u32 len);
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| 
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| static int crct10dif_init(struct shash_desc *desc)
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| {
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| 	u16 *crc = shash_desc_ctx(desc);
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| 
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| 	*crc = 0;
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| 	return 0;
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| }
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| 
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| static int crct10dif_update(struct shash_desc *desc, const u8 *data,
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| 			    unsigned int length)
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| {
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| 	u16 *crc = shash_desc_ctx(desc);
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| 
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| 	if (length >= CRC_T10DIF_PMULL_CHUNK_SIZE && may_use_simd()) {
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| 		kernel_neon_begin();
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| 		*crc = crc_t10dif_pmull(*crc, data, length);
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| 		kernel_neon_end();
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| 	} else {
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| 		*crc = crc_t10dif_generic(*crc, data, length);
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| 	}
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| 
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| 	return 0;
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| }
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| 
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| static int crct10dif_final(struct shash_desc *desc, u8 *out)
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| {
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| 	u16 *crc = shash_desc_ctx(desc);
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| 
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| 	*(u16 *)out = *crc;
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| 	return 0;
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| }
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| 
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| static struct shash_alg crc_t10dif_alg = {
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| 	.digestsize		= CRC_T10DIF_DIGEST_SIZE,
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| 	.init			= crct10dif_init,
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| 	.update			= crct10dif_update,
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| 	.final			= crct10dif_final,
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| 	.descsize		= CRC_T10DIF_DIGEST_SIZE,
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| 
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| 	.base.cra_name		= "crct10dif",
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| 	.base.cra_driver_name	= "crct10dif-arm-ce",
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| 	.base.cra_priority	= 200,
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| 	.base.cra_blocksize	= CRC_T10DIF_BLOCK_SIZE,
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| 	.base.cra_module	= THIS_MODULE,
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| };
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| 
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| static int __init crc_t10dif_mod_init(void)
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| {
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| 	if (!(elf_hwcap2 & HWCAP2_PMULL))
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| 		return -ENODEV;
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| 
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| 	return crypto_register_shash(&crc_t10dif_alg);
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| }
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| 
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| static void __exit crc_t10dif_mod_exit(void)
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| {
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| 	crypto_unregister_shash(&crc_t10dif_alg);
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| }
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| 
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| module_init(crc_t10dif_mod_init);
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| module_exit(crc_t10dif_mod_exit);
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| 
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| MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
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| MODULE_LICENSE("GPL v2");
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| MODULE_ALIAS_CRYPTO("crct10dif");
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