crypto: aes - move sync ctr(aes) to AES library and generic helper

In preparation of duplicating the sync ctr(aes) functionality to modules
under arch/arm, move the helper function from a inline .h file to the
AES library, which is already depended upon by the drivers that use this
fallback.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 16 insertions, 5 deletions

diff --git a/arch/arm64/crypto/aes-neonbs-glue.c b/arch/arm64/crypto/aes-neonbs-glue.c
index 25fe51eedc98..bafd2ebef8f1 100644
--- a/arch/arm64/crypto/aes-neonbs-glue.c
+++ b/arch/arm64/crypto/aes-neonbs-glue.c
@@ -8,13 +8,12 @@
 #include <asm/neon.h>
 #include <asm/simd.h>
 #include <crypto/aes.h>
+#include <crypto/ctr.h>
 #include <crypto/internal/simd.h>
 #include <crypto/internal/skcipher.h>
 #include <crypto/xts.h>
 #include <linux/module.h>
 
-#include "aes-ctr-fallback.h"
-
 MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
 MODULE_LICENSE("GPL v2");
 
@@ -280,13 +279,25 @@ static int aesbs_xts_setkey(struct crypto_skcipher *tfm, const u8 *in_key,
 	return aesbs_setkey(tfm, in_key, key_len);
 }
 
-static int ctr_encrypt_sync(struct skcipher_request *req)
+static void ctr_encrypt_one(struct crypto_skcipher *tfm, const u8 *src, u8 *dst)
 {
-	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 	struct aesbs_ctr_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->fallback, dst, src);
+	local_irq_restore(flags);
+}
 
+static int ctr_encrypt_sync(struct skcipher_request *req)
+{
 	if (!crypto_simd_usable())
-		return aes_ctr_encrypt_fallback(&ctx->fallback, req);
+		return crypto_ctr_encrypt_walk(req, ctr_encrypt_one);
 
 	return ctr_encrypt(req);
 }