Re: [PATCH net-next v6 21/23] crypto: port ChaCha20 to Zinc

diff --git a/crypto/chacha20_zinc.c b/crypto/chacha20_zinc.c
new file mode 100644
index 000000000000..f7d70b3efc31
--- /dev/null
+++ b/crypto/chacha20_zinc.c

@@ -0,0 +1,90 @@
+/* SPDX-License-Identifier: GPL-2.0
+ *
+ * Copyright (C) 2018 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#include <asm/unaligned.h>
+#include <crypto/algapi.h>
+#include <crypto/internal/skcipher.h>
+#include <zinc/chacha20.h>
+#include <linux/module.h>
+
+static int crypto_chacha20_setkey(struct crypto_skcipher *tfm, const u8 *key,
+				  unsigned int keysize)
+{
+	struct chacha20_ctx *ctx = crypto_skcipher_ctx(tfm);
+
+	if (keysize != CHACHA20_KEY_SIZE)
+		return -EINVAL;
+	chacha20_init(ctx, key, 0);
+	return 0;
+}
+
+static int crypto_chacha20_crypt(struct skcipher_request *req)
+{
+	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+	struct chacha20_ctx *ctx = crypto_skcipher_ctx(tfm);
+	struct skcipher_walk walk;
+	simd_context_t simd_context;
+	int err, i;
+
+	err = skcipher_walk_virt(&walk, req, true);
+	if (unlikely(err))
+		return err;
+
+	for (i = 0; i < ARRAY_SIZE(ctx->counter); ++i)
+		ctx->counter[i] = get_unaligned_le32(walk.iv + i * sizeof(u32));
+