[RFC PATCH 05/20] crypto: x86/aes-ni - switch to generic for fallback and key routines

[Ard Biesheuvel <ard.biesheuvel@linaro.org>]

The AES-NI code contains fallbacks for invocations that occur from a
context where the SIMD unit is unavailable, which really only occurs
when running in softirq context that was entered from a hard IRQ that
was taken while running kernel code that was already using the FPU.

That means performance is not really a consideration, and we can just
use the new library code for this use case, which has a smaller
footprint and is believed to be time invariant. This will allow us to
drop the non-SIMD asm routines in a subsequent patch.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
 arch/x86/crypto/aesni-intel_glue.c | 15 +++++++--------
 arch/x86/include/asm/crypto/aes.h  | 12 ------------
 crypto/Kconfig                     |  3 +--
 3 files changed, 8 insertions(+), 22 deletions(-)

diff --git a/arch/x86/crypto/aesni-intel_glue.c b/arch/x86/crypto/aesni-intel_glue.c
index e9b866e87d48..9952bd312ddc 100644
--- a/arch/x86/crypto/aesni-intel_glue.c
+++ b/arch/x86/crypto/aesni-intel_glue.c
@@ -26,7 +26,6 @@
 #include <crypto/gcm.h>
 #include <crypto/xts.h>
 #include <asm/cpu_device_id.h>
-#include <asm/crypto/aes.h>
 #include <asm/simd.h>
 #include <crypto/scatterwalk.h>
 #include <crypto/internal/aead.h>
@@ -329,7 +328,7 @@ static int aes_set_key_common(struct crypto_tfm *tfm, void *raw_ctx,
 	}
 
 	if (!crypto_simd_usable())
-		err = crypto_aes_expand_key(ctx, in_key, key_len);
+		err = aes_expandkey(ctx, in_key, key_len);
 	else {
 		kernel_fpu_begin();
 		err = aesni_set_key(ctx, in_key, key_len);
@@ -349,9 +348,9 @@ static void aes_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
 {
 	struct crypto_aes_ctx *ctx = aes_ctx(crypto_tfm_ctx(tfm));
 
-	if (!crypto_simd_usable())
-		crypto_aes_encrypt_x86(ctx, dst, src);
-	else {
+	if (!crypto_simd_usable()) {
+		aes_encrypt(ctx, dst, src);
+	} else {
 		kernel_fpu_begin();
 		aesni_enc(ctx, dst, src);
 		kernel_fpu_end();
@@ -362,9 +361,9 @@ static void aes_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
 {
 	struct crypto_aes_ctx *ctx = aes_ctx(crypto_tfm_ctx(tfm));
 
-	if (!crypto_simd_usable())
-		crypto_aes_decrypt_x86(ctx, dst, src);
-	else {
+	if (!crypto_simd_usable()) {
+		aes_decrypt(ctx, dst, src);
+	} else {
 		kernel_fpu_begin();
 		aesni_dec(ctx, dst, src);
 		kernel_fpu_end();
diff --git a/arch/x86/include/asm/crypto/aes.h b/arch/x86/include/asm/crypto/aes.h
deleted file mode 100644
index c508521dd190..000000000000
--- a/arch/x86/include/asm/crypto/aes.h
+++ /dev/null
@@ -1,12 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef ASM_X86_AES_H
-#define ASM_X86_AES_H
-
-#include <linux/crypto.h>
-#include <crypto/aes.h>
-
-void crypto_aes_encrypt_x86(struct crypto_aes_ctx *ctx, u8 *dst,
-			    const u8 *src);
-void crypto_aes_decrypt_x86(struct crypto_aes_ctx *ctx, u8 *dst,
-			    const u8 *src);
-#endif
diff --git a/crypto/Kconfig b/crypto/Kconfig
index dc6f93ef3ead..0d80985016bf 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -1149,8 +1149,7 @@ config CRYPTO_AES_NI_INTEL
 	tristate "AES cipher algorithms (AES-NI)"
 	depends on X86
 	select CRYPTO_AEAD
-	select CRYPTO_AES_X86_64 if 64BIT
-	select CRYPTO_AES_586 if !64BIT
+	select CRYPTO_LIB_AES
 	select CRYPTO_ALGAPI
 	select CRYPTO_BLKCIPHER
 	select CRYPTO_GLUE_HELPER_X86 if 64BIT
-- 
2.20.1