1 files changed, 121 insertions, 0 deletions
diff --git a/sys/contrib/openzfs/module/zfs/blake3_zfs.c b/sys/contrib/openzfs/module/zfs/blake3_zfs.c
new file mode 100644
index 000000000000..49514c4d471a
--- /dev/null
+++ b/sys/contrib/openzfs/module/zfs/blake3_zfs.c
@@ -0,0 +1,121 @@
+// SPDX-License-Identifier: CDDL-1.0
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://opensource.org/licenses/CDDL-1.0.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+
+/*
+ * Copyright 2022 Tino Reichardt <milky-zfs@mcmilk.de>
+ */
+
+#include <sys/zfs_context.h>
+#include <sys/zio_checksum.h>
+#include <sys/blake3.h>
+#include <sys/abd.h>
+
+static int
+blake3_incremental(void *buf, size_t size, void *arg)
+{
+	BLAKE3_CTX *ctx = arg;
+
+	Blake3_Update(ctx, buf, size);
+
+	return (0);
+}
+
+/*
+ * Computes a native 256-bit BLAKE3 MAC checksum. Please note that this
+ * function requires the presence of a ctx_template that should be allocated
+ * using abd_checksum_blake3_tmpl_init.
+ */
+void
+abd_checksum_blake3_native(abd_t *abd, uint64_t size, const void *ctx_template,
+    zio_cksum_t *zcp)
+{
+	ASSERT(ctx_template != NULL);
+
+#if defined(_KERNEL)
+	kpreempt_disable();
+	BLAKE3_CTX *ctx = blake3_per_cpu_ctx[CPU_SEQID];
+#else
+	BLAKE3_CTX *ctx = kmem_alloc(sizeof (*ctx), KM_SLEEP);
+#endif
+
+	memcpy(ctx, ctx_template, sizeof (*ctx));
+	(void) abd_iterate_func(abd, 0, size, blake3_incremental, ctx);
+	Blake3_Final(ctx, (uint8_t *)zcp);
+
+#if defined(_KERNEL)
+	kpreempt_enable();
+#else
+	memset(ctx, 0, sizeof (*ctx));
+	kmem_free(ctx, sizeof (*ctx));
+#endif
+}
+
+/*
+ * Byteswapped version of abd_checksum_blake3_native. This just invokes
+ * the native checksum function and byteswaps the resulting checksum (since
+ * BLAKE3 is internally endian-insensitive).
+ */
+void
+abd_checksum_blake3_byteswap(abd_t *abd, uint64_t size,
+    const void *ctx_template, zio_cksum_t *zcp)
+{
+	zio_cksum_t tmp;
+
+	ASSERT(ctx_template != NULL);
+
+	abd_checksum_blake3_native(abd, size, ctx_template, &tmp);
+	zcp->zc_word[0] = BSWAP_64(tmp.zc_word[0]);
+	zcp->zc_word[1] = BSWAP_64(tmp.zc_word[1]);
+	zcp->zc_word[2] = BSWAP_64(tmp.zc_word[2]);
+	zcp->zc_word[3] = BSWAP_64(tmp.zc_word[3]);
+}
+
+/*
+ * Allocates a BLAKE3 MAC template suitable for using in BLAKE3 MAC checksum
+ * computations and returns a pointer to it.
+ */
+void *
+abd_checksum_blake3_tmpl_init(const zio_cksum_salt_t *salt)
+{
+	BLAKE3_CTX *ctx;
+
+	ASSERT(sizeof (salt->zcs_bytes) == 32);
+
+	/* init reference object */
+	ctx = kmem_zalloc(sizeof (*ctx), KM_SLEEP);
+	Blake3_InitKeyed(ctx, salt->zcs_bytes);
+
+	return (ctx);
+}
+
+/*
+ * Frees a BLAKE3 context template previously allocated using
+ * zio_checksum_blake3_tmpl_init.
+ */
+void
+abd_checksum_blake3_tmpl_free(void *ctx_template)
+{
+	BLAKE3_CTX *ctx = ctx_template;
+
+	memset(ctx, 0, sizeof (*ctx));
+	kmem_free(ctx, sizeof (*ctx));
+}