[RFC PATCH 2/3] crypto: arm/aes-ce - drop non-SIMD fallbacks and SIMD helper

[Ard Biesheuvel]

Now that kernel mode NEON is guaranteed to be available both in process
and in softirq context, we no longer have a need for the SIMD helper or
for non-SIMD fallbacks, given that the skcipher API is not supported in
any other context anyway. So drop this code.

Signed-off-by: Ard Biesheuvel <ardb at kernel.org>
---
 arch/arm/crypto/aes-ce-glue.c | 84 +-------------------
 1 file changed, 3 insertions(+), 81 deletions(-)

diff --git a/arch/arm/crypto/aes-ce-glue.c b/arch/arm/crypto/aes-ce-glue.c
index b668c97663ec..bcb2b6695241 100644
--- a/arch/arm/crypto/aes-ce-glue.c
+++ b/arch/arm/crypto/aes-ce-glue.c
@@ -7,11 +7,9 @@
 
 #include <asm/hwcap.h>
 #include <asm/neon.h>
-#include <asm/simd.h>
 #include <asm/unaligned.h>
 #include <crypto/aes.h>
 #include <crypto/ctr.h>
-#include <crypto/internal/simd.h>
 #include <crypto/internal/skcipher.h>
 #include <crypto/scatterwalk.h>
 #include <linux/cpufeature.h>
@@ -418,29 +416,6 @@ static int ctr_encrypt(struct skcipher_request *req)
 	return err;
 }
 
-static void ctr_encrypt_one(struct crypto_skcipher *tfm, const u8 *src, u8 *dst)
-{
-	struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm);
-	unsigned long flags;
-
-	/*
-	 * Temporarily disable interrupts to avoid races where
-	 * cachelines are evicted when the CPU is interrupted
-	 * to do something else.
-	 */
-	local_irq_save(flags);
-	aes_encrypt(ctx, dst, src);
-	local_irq_restore(flags);
-}
-
-static int ctr_encrypt_sync(struct skcipher_request *req)
-{
-	if (!crypto_simd_usable())
-		return crypto_ctr_encrypt_walk(req, ctr_encrypt_one);
-
-	return ctr_encrypt(req);
-}
-
 static int xts_encrypt(struct skcipher_request *req)
 {
 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
@@ -647,25 +622,9 @@ static struct skcipher_alg aes_algs[] = { {
 	.encrypt		= ctr_encrypt,
 	.decrypt		= ctr_encrypt,
 }, {
-	.base.cra_name		= "ctr(aes)",
-	.base.cra_driver_name	= "ctr-aes-ce-sync",
-	.base.cra_priority	= 300 - 1,
-	.base.cra_blocksize	= 1,
-	.base.cra_ctxsize	= sizeof(struct crypto_aes_ctx),
-	.base.cra_module	= THIS_MODULE,
-
-	.min_keysize		= AES_MIN_KEY_SIZE,
-	.max_keysize		= AES_MAX_KEY_SIZE,
-	.ivsize			= AES_BLOCK_SIZE,
-	.chunksize		= AES_BLOCK_SIZE,
-	.setkey			= ce_aes_setkey,
-	.encrypt		= ctr_encrypt_sync,
-	.decrypt		= ctr_encrypt_sync,
-}, {
-	.base.cra_name		= "__xts(aes)",
-	.base.cra_driver_name	= "__xts-aes-ce",
+	.base.cra_name		= "xts(aes)",
+	.base.cra_driver_name	= "xts-aes-ce",
 	.base.cra_priority	= 300,
-	.base.cra_flags		= CRYPTO_ALG_INTERNAL,
 	.base.cra_blocksize	= AES_BLOCK_SIZE,
 	.base.cra_ctxsize	= sizeof(struct crypto_aes_xts_ctx),
 	.base.cra_module	= THIS_MODULE,
@@ -679,51 +638,14 @@ static struct skcipher_alg aes_algs[] = { {
 	.decrypt		= xts_decrypt,
 } };
 
-static struct simd_skcipher_alg *aes_simd_algs[ARRAY_SIZE(aes_algs)];
-
 static void aes_exit(void)
 {
-	int i;
-
-	for (i = 0; i < ARRAY_SIZE(aes_simd_algs) && aes_simd_algs[i]; i++)
-		simd_skcipher_free(aes_simd_algs[i]);
-
 	crypto_unregister_skciphers(aes_algs, ARRAY_SIZE(aes_algs));
 }
 
 static int __init aes_init(void)
 {
-	struct simd_skcipher_alg *simd;
-	const char *basename;
-	const char *algname;
-	const char *drvname;
-	int err;
-	int i;
-
-	err = crypto_register_skciphers(aes_algs, ARRAY_SIZE(aes_algs));
-	if (err)
-		return err;
-
-	for (i = 0; i < ARRAY_SIZE(aes_algs); i++) {
-		if (!(aes_algs[i].base.cra_flags & CRYPTO_ALG_INTERNAL))
-			continue;
-
-		algname = aes_algs[i].base.cra_name + 2;
-		drvname = aes_algs[i].base.cra_driver_name + 2;
-		basename = aes_algs[i].base.cra_driver_name;
-		simd = simd_skcipher_create_compat(algname, drvname, basename);
-		err = PTR_ERR(simd);
-		if (IS_ERR(simd))
-			goto unregister_simds;
-
-		aes_simd_algs[i] = simd;
-	}
-
-	return 0;
-
-unregister_simds:
-	aes_exit();
-	return err;
+	return crypto_register_skciphers(aes_algs, ARRAY_SIZE(aes_algs));
 }
 
 module_cpu_feature_match(AES, aes_init);
-- 
2.17.1