v4.19.13 snapshot.
diff --git a/arch/x86/crypto/chacha20_glue.c b/arch/x86/crypto/chacha20_glue.c
new file mode 100644
index 0000000..dce7c5d
--- /dev/null
+++ b/arch/x86/crypto/chacha20_glue.c
@@ -0,0 +1,146 @@
+/*
+ * ChaCha20 256-bit cipher algorithm, RFC7539, SIMD glue code
+ *
+ * Copyright (C) 2015 Martin Willi
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <crypto/algapi.h>
+#include <crypto/chacha20.h>
+#include <crypto/internal/skcipher.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <asm/fpu/api.h>
+#include <asm/simd.h>
+
+#define CHACHA20_STATE_ALIGN 16
+
+asmlinkage void chacha20_block_xor_ssse3(u32 *state, u8 *dst, const u8 *src);
+asmlinkage void chacha20_4block_xor_ssse3(u32 *state, u8 *dst, const u8 *src);
+#ifdef CONFIG_AS_AVX2
+asmlinkage void chacha20_8block_xor_avx2(u32 *state, u8 *dst, const u8 *src);
+static bool chacha20_use_avx2;
+#endif
+
+static void chacha20_dosimd(u32 *state, u8 *dst, const u8 *src,
+ unsigned int bytes)
+{
+ u8 buf[CHACHA20_BLOCK_SIZE];
+
+#ifdef CONFIG_AS_AVX2
+ if (chacha20_use_avx2) {
+ while (bytes >= CHACHA20_BLOCK_SIZE * 8) {
+ chacha20_8block_xor_avx2(state, dst, src);
+ bytes -= CHACHA20_BLOCK_SIZE * 8;
+ src += CHACHA20_BLOCK_SIZE * 8;
+ dst += CHACHA20_BLOCK_SIZE * 8;
+ state[12] += 8;
+ }
+ }
+#endif
+ while (bytes >= CHACHA20_BLOCK_SIZE * 4) {
+ chacha20_4block_xor_ssse3(state, dst, src);
+ bytes -= CHACHA20_BLOCK_SIZE * 4;
+ src += CHACHA20_BLOCK_SIZE * 4;
+ dst += CHACHA20_BLOCK_SIZE * 4;
+ state[12] += 4;
+ }
+ while (bytes >= CHACHA20_BLOCK_SIZE) {
+ chacha20_block_xor_ssse3(state, dst, src);
+ bytes -= CHACHA20_BLOCK_SIZE;
+ src += CHACHA20_BLOCK_SIZE;
+ dst += CHACHA20_BLOCK_SIZE;
+ state[12]++;
+ }
+ if (bytes) {
+ memcpy(buf, src, bytes);
+ chacha20_block_xor_ssse3(state, buf, buf);
+ memcpy(dst, buf, bytes);
+ }
+}
+
+static int chacha20_simd(struct skcipher_request *req)
+{
+ struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+ struct chacha20_ctx *ctx = crypto_skcipher_ctx(tfm);
+ u32 *state, state_buf[16 + 2] __aligned(8);
+ struct skcipher_walk walk;
+ int err;
+
+ BUILD_BUG_ON(CHACHA20_STATE_ALIGN != 16);
+ state = PTR_ALIGN(state_buf + 0, CHACHA20_STATE_ALIGN);
+
+ if (req->cryptlen <= CHACHA20_BLOCK_SIZE || !may_use_simd())
+ return crypto_chacha20_crypt(req);
+
+ err = skcipher_walk_virt(&walk, req, true);
+
+ crypto_chacha20_init(state, ctx, walk.iv);
+
+ kernel_fpu_begin();
+
+ while (walk.nbytes >= CHACHA20_BLOCK_SIZE) {
+ chacha20_dosimd(state, walk.dst.virt.addr, walk.src.virt.addr,
+ rounddown(walk.nbytes, CHACHA20_BLOCK_SIZE));
+ err = skcipher_walk_done(&walk,
+ walk.nbytes % CHACHA20_BLOCK_SIZE);
+ }
+
+ if (walk.nbytes) {
+ chacha20_dosimd(state, walk.dst.virt.addr, walk.src.virt.addr,
+ walk.nbytes);
+ err = skcipher_walk_done(&walk, 0);
+ }
+
+ kernel_fpu_end();
+
+ return err;
+}
+
+static struct skcipher_alg alg = {
+ .base.cra_name = "chacha20",
+ .base.cra_driver_name = "chacha20-simd",
+ .base.cra_priority = 300,
+ .base.cra_blocksize = 1,
+ .base.cra_ctxsize = sizeof(struct chacha20_ctx),
+ .base.cra_module = THIS_MODULE,
+
+ .min_keysize = CHACHA20_KEY_SIZE,
+ .max_keysize = CHACHA20_KEY_SIZE,
+ .ivsize = CHACHA20_IV_SIZE,
+ .chunksize = CHACHA20_BLOCK_SIZE,
+ .setkey = crypto_chacha20_setkey,
+ .encrypt = chacha20_simd,
+ .decrypt = chacha20_simd,
+};
+
+static int __init chacha20_simd_mod_init(void)
+{
+ if (!boot_cpu_has(X86_FEATURE_SSSE3))
+ return -ENODEV;
+
+#ifdef CONFIG_AS_AVX2
+ chacha20_use_avx2 = boot_cpu_has(X86_FEATURE_AVX) &&
+ boot_cpu_has(X86_FEATURE_AVX2) &&
+ cpu_has_xfeatures(XFEATURE_MASK_SSE | XFEATURE_MASK_YMM, NULL);
+#endif
+ return crypto_register_skcipher(&alg);
+}
+
+static void __exit chacha20_simd_mod_fini(void)
+{
+ crypto_unregister_skcipher(&alg);
+}
+
+module_init(chacha20_simd_mod_init);
+module_exit(chacha20_simd_mod_fini);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Martin Willi <martin@strongswan.org>");
+MODULE_DESCRIPTION("chacha20 cipher algorithm, SIMD accelerated");
+MODULE_ALIAS_CRYPTO("chacha20");
+MODULE_ALIAS_CRYPTO("chacha20-simd");