Commit 87c9b04e authored by Ard Biesheuvel's avatar Ard Biesheuvel
Browse files

crypto/arm64: aes-gcm - Switch to 'ksimd' scoped guard API 



Switch to the more abstract 'scoped_ksimd()' API, which will be modified
in a future patch to transparently allocate a kernel mode FP/SIMD state
buffer on the stack, so that kernel mode FP/SIMD code remains
preemptible in principe, but without the memory overhead that adds 528
bytes to the size of struct task_struct.

Reviewed-by: default avatarEric Biggers <ebiggers@kernel.org>
Reviewed-by: default avatarJonathan Cameron <jonathan.cameron@huawei.com>
Acked-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: default avatarArd Biesheuvel <ardb@kernel.org>
parent ba3c1b3b

arch/arm64/crypto/ghash-ce-glue.c

+13 −14
Original line number Diff line number Diff line
@@ -5,7 +5,6 @@ 
 * Copyright (C) 2014 - 2018 Linaro Ltd. <ard.biesheuvel@linaro.org>

 */



#include <asm/neon.h>

#include <crypto/aes.h>

#include <crypto/b128ops.h>

#include <crypto/gcm.h>
@@ -22,6 +21,8 @@ 
#include <linux/string.h>

#include <linux/unaligned.h>



#include <asm/simd.h>



MODULE_DESCRIPTION("GHASH and AES-GCM using ARMv8 Crypto Extensions");

MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");

MODULE_LICENSE("GPL v2");
@@ -74,9 +75,8 @@ void ghash_do_simd_update(int blocks, u64 dg[], const char *src, 
					      u64 const h[][2],

					      const char *head))

{

	kernel_neon_begin();

	scoped_ksimd()

		simd_update(blocks, dg, src, key->h, head);

	kernel_neon_end();

}



/* avoid hogging the CPU for too long */
@@ -329,11 +329,10 @@ static int gcm_encrypt(struct aead_request *req, char *iv, int assoclen) 
			tag = NULL;

		}



		kernel_neon_begin();

		scoped_ksimd()

			pmull_gcm_encrypt(nbytes, dst, src, ctx->ghash_key.h,

					  dg, iv, ctx->aes_key.key_enc, nrounds,

					  tag);

		kernel_neon_end();



		if (unlikely(!nbytes))

			break;
@@ -399,11 +398,11 @@ static int gcm_decrypt(struct aead_request *req, char *iv, int assoclen) 
			tag = NULL;

		}



		kernel_neon_begin();

		ret = pmull_gcm_decrypt(nbytes, dst, src, ctx->ghash_key.h,

		scoped_ksimd()

			ret = pmull_gcm_decrypt(nbytes, dst, src,

						ctx->ghash_key.h,

						dg, iv, ctx->aes_key.key_enc,

						nrounds, tag, otag, authsize);

		kernel_neon_end();



		if (unlikely(!nbytes))

			break;