Add FreeBSD support to OpenZFS

Add the FreeBSD platform code to the OpenZFS repository.  As of this
commit the source can be compiled and tested on FreeBSD 11 and 12.
Subsequent commits are now required to compile on FreeBSD and Linux.
Additionally, they must pass the ZFS Test Suite on FreeBSD which is
being run by the CI.  As of this commit 1230 tests pass on FreeBSD
and there are no unexpected failures.

Reviewed-by: Sean Eric Fagan <[email protected]>
Reviewed-by: Jorgen Lundman <[email protected]>
Reviewed-by: Richard Laager <[email protected]>
Reviewed-by: Brian Behlendorf <[email protected]>
Co-authored-by: Ryan Moeller <[email protected]>
Signed-off-by: Matt Macy <[email protected]>
Signed-off-by: Ryan Moeller <[email protected]>
Closes #898 
Closes #8987 

1 files changed, 36 insertions, 0 deletions

diff --git a/lib/libspl/os/freebsd/gethostid.c b/lib/libspl/os/freebsd/gethostid.c
new file mode 100644
index 000000000..7bd567fe6
--- /dev/null
+++ b/lib/libspl/os/freebsd/gethostid.c
@@ -0,0 +1,36 @@
+/*
+ * 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://www.opensolaris.org/os/licensing.
+ * 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 (c) 2017, Lawrence Livermore National Security, LLC.
+ */
+
+#include <fcntl.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/systeminfo.h>
+
+unsigned long
+get_system_hostid(void)
+{
+	return (gethostid());
+}