Add forwards compatibility for libzfs_core

Unsupported: creation of multiple snapshots including "zfs snapshot -r"

cddl/contrib/opensolaris/lib/libzfs_core/common/libzfs_core.c

@@ -86,6 +86,10 @@
 #include <sys/zfs_ioctl.h>
 #include <libzfs_compat.h>
 
+#ifdef __FreeBSD__
+extern int zfs_ioctl_version;
+#endif
+
 static int g_fd;
 static pthread_mutex_t g_lock = PTHREAD_MUTEX_INITIALIZER;
 static int g_refcount;
@@ -124,12 +128,24 @@ lzc_ioctl(zfs_ioc_t ioc, const char *name,
 	zfs_cmd_t zc = { 0 };
 	int error = 0;
 	char *packed;
+#ifdef __FreeBSD__
+	nvlist_t *oldsource;
+#endif
 	size_t size;
 
 	ASSERT3S(g_refcount, >, 0);
 
 	(void) strlcpy(zc.zc_name, name, sizeof (zc.zc_name));
 
+#ifdef __FreeBSD__
+	if (zfs_ioctl_version < ZFS_IOCVER_LZC) {
+		oldsource = source;
+		error = lzc_compat_pre(&zc, &ioc, &source);
+		if (error)
+			return (error);
+	}
+#endif
+
 	packed = fnvlist_pack(source, &size);
 	zc.zc_nvlist_src = (uint64_t)(uintptr_t)packed;
 	zc.zc_nvlist_src_size = size;
@@ -167,14 +183,29 @@ lzc_ioctl(zfs_ioc_t ioc, const char *name,
 			break;
 		}
 	}
+
+#ifdef __FreeBSD__
+	if (zfs_ioctl_version < ZFS_IOCVER_LZC)
+		lzc_compat_post(&zc, ioc);
+#endif
 	if (zc.zc_nvlist_dst_filled) {
 		*resultp = fnvlist_unpack((void *)(uintptr_t)zc.zc_nvlist_dst,
 		    zc.zc_nvlist_dst_size);
 	} else if (resultp != NULL) {
 		*resultp = NULL;
 	}
-
+#ifdef __FreeBSD__
+	if (zfs_ioctl_version < ZFS_IOCVER_LZC)
+		lzc_compat_outnvl(&zc, ioc, resultp);
+#endif
 out:
+#ifdef __FreeBSD__
+	if (zfs_ioctl_version < ZFS_IOCVER_LZC) {
+		if (source != oldsource)
+			nvlist_free(source);
+		source = oldsource;
+	}
+#endif
 	fnvlist_pack_free(packed, size);
 	free((void *)(uintptr_t)zc.zc_nvlist_dst);
 	return (error);

cddl/contrib/opensolaris/lib/libzfs_core/common/libzfs_core.h

@@ -31,6 +31,9 @@
 #include <sys/param.h>
 #include <sys/types.h>
 #include <sys/fs/zfs.h>
+#ifdef __FreeBSD__
+#include "libzfs_core_compat.h"
+#endif
 
 #ifdef	__cplusplus
 extern "C" {

cddl/contrib/opensolaris/lib/libzfs_core/common/libzfs_core_compat.c

@@ -0,0 +1,134 @@
+/*
+ * 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) 2013 Martin Matuska <mm@FreeBSD.org>. All rights reserved.
+ */
+
+#include <sys/zfs_ioctl.h>
+#include <libzfs_compat.h>
+
+extern int zfs_ioctl_version;
+
+int
+lzc_compat_pre(zfs_cmd_t *zc, zfs_ioc_t *ioc, nvlist_t **source)
+{
+	nvlist_t *nvl = NULL;
+	nvpair_t *pair;
+	char *buf;
+	zfs_ioc_t vecnum;
+	uint32_t type32;
+	int error = 0;
+	int pos;
+
+	if (zfs_ioctl_version >= ZFS_IOCVER_LZC)
+		return (0);
+
+	vecnum = *ioc;
+
+	switch (vecnum) {
+	case ZFS_IOC_CREATE:
+		type32 = fnvlist_lookup_int32(*source, "type");
+		zc->zc_objset_type = (uint64_t)type32;
+		nvlist_lookup_nvlist(*source, "props", &nvl);
+		*source = nvl;
+	break;
+	case ZFS_IOC_CLONE:
+		buf = fnvlist_lookup_string(*source, "origin");
+		strlcpy(zc->zc_value, buf, MAXPATHLEN);
+		nvlist_lookup_nvlist(*source, "props", &nvl);
+		*ioc = ZFS_IOC_CREATE;
+		*source = nvl;
+	break;
+	case ZFS_IOC_SNAPSHOT:
+		nvl = fnvlist_lookup_nvlist(*source, "snaps");
+		pair = nvlist_next_nvpair(nvl, NULL);
+		if (pair != NULL) {
+			buf = nvpair_name(pair);
+			pos = strcspn(buf, "@");
+			strlcpy(zc->zc_name, buf, pos + 1);
+			strlcpy(zc->zc_value, buf + pos + 1, MAXPATHLEN);
+		} else
+			error = EOPNOTSUPP;
+		/* old kernel cannot create multiple snapshots */
+		if (!error && nvlist_next_nvpair(nvl, pair) != NULL)
+			error = EOPNOTSUPP;
+		nvlist_free(nvl);
+		nvl = NULL;
+		nvlist_lookup_nvlist(*source, "props", &nvl);
+		*source = nvl;
+	break;
+	case ZFS_IOC_SPACE_SNAPS:
+		buf = fnvlist_lookup_string(*source, "firstsnap");
+		strlcpy(zc->zc_value, buf, MAXPATHLEN);
+	break;
+	case ZFS_IOC_DESTROY_SNAPS:
+		nvl = fnvlist_lookup_nvlist(*source, "snaps");
+		pair = nvlist_next_nvpair(nvl, NULL);
+		if (pair != NULL) {
+			buf = nvpair_name(pair);
+			pos = strcspn(buf, "@");
+			strlcpy(zc->zc_name, buf, pos + 1);
+		}
+		*source = nvl;
+	break;
+	}
+
+	return (error);
+}
+
+void
+lzc_compat_post(zfs_cmd_t *zc, const zfs_ioc_t ioc)
+{
+	if (zfs_ioctl_version >= ZFS_IOCVER_LZC)
+		return;
+
+	switch (ioc) {
+	case ZFS_IOC_CREATE:
+	case ZFS_IOC_CLONE:
+	case ZFS_IOC_SNAPSHOT:
+	case ZFS_IOC_SPACE_SNAPS:
+	case ZFS_IOC_DESTROY_SNAPS:
+		zc->zc_nvlist_dst_filled = B_FALSE;
+	break;
+	}
+}
+
+int
+lzc_compat_outnvl(zfs_cmd_t *zc, const zfs_ioc_t ioc, nvlist_t **outnvl)
+{
+	nvlist_t *nvl;
+
+	if (zfs_ioctl_version >= ZFS_IOCVER_LZC)
+		return (0);
+
+	switch (ioc) {
+	case ZFS_IOC_SPACE_SNAPS:
+		nvl = fnvlist_alloc();
+		fnvlist_add_uint64(nvl, "used", zc->zc_cookie);
+		fnvlist_add_uint64(nvl, "compressed", zc->zc_objset_type);
+		fnvlist_add_uint64(nvl, "uncompressed", zc->zc_perm_action);
+		*outnvl = nvl;
+	break;
+	}
+
+	return (0);
+}

cddl/contrib/opensolaris/lib/libzfs_core/common/libzfs_core_compat.h

@@ -0,0 +1,47 @@
+/*
+ * 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) 2013 by Martin Matuska <mm@FreeBSD.org>. All rights reserved.
+ */
+
+#ifndef	_LIBZFS_CORE_COMPAT_H
+#define	_LIBZFS_CORE_COMPAT_H
+
+#include <libnvpair.h>
+#include <sys/param.h>
+#include <sys/types.h>
+#include <sys/fs/zfs.h>
+#include <sys/zfs_ioctl.h>
+
+#ifdef	__cplusplus
+extern "C" {
+#endif
+
+int lzc_compat_pre(zfs_cmd_t *, zfs_ioc_t *, nvlist_t **);
+void lzc_compat_post(zfs_cmd_t *, const zfs_ioc_t);
+int lzc_compat_outnvl(zfs_cmd_t *, const zfs_ioc_t, nvlist_t **);
+
+#ifdef	__cplusplus
+}
+#endif
+
+#endif	/* _LIBZFS_CORE_COMPAT_H */

cddl/lib/libzfs_core/Makefile

@@ -9,7 +9,7 @@ LIB=	zfs_core
 DPADD=	${LIBNVPAIR}
 LDADD=	-lnvpair
 
-SRCS=	libzfs_core.c
+SRCS=	libzfs_core.c libzfs_core_compat.c
 
 WARNS?=	0
 CSTD=	c99