Illumos #2882, #2883, #2900

2882 implement libzfs_core
2883 changing "canmount" property to "on" should not always remount dataset
2900 "zfs snapshot" should be able to create multiple, arbitrary snapshots at once

Reviewed by: George Wilson <[email protected]>
Reviewed by: Chris Siden <[email protected]>
Reviewed by: Garrett D'Amore <[email protected]>
Reviewed by: Bill Pijewski <[email protected]>
Reviewed by: Dan Kruchinin <[email protected]>
Approved by: Eric Schrock <[email protected]>

References:
  https://www.illumos.org/issues/2882
  https://www.illumos.org/issues/2883
  https://www.illumos.org/issues/2900
  illumos/illumos-gate@4445fffbbb1ea25fd0e9ea68b9380dd7a6709025

Ported-by: Tim Chase <[email protected]>
Signed-off-by: Brian Behlendorf <[email protected]>
Closes #1293

Porting notes:

WARNING: This patch changes the user/kernel ABI.  That means that
the zfs/zpool utilities built from master are NOT compatible with
the 0.6.2 kernel modules.  Ensure you load the matching kernel
modules from master after updating the utilities.  Otherwise the
zfs/zpool commands will be unable to interact with your pool and
you will see errors similar to the following:

  $ zpool list
  failed to read pool configuration: bad address
  no pools available

  $ zfs list
  no datasets available

Add zvol minor device creation to the new zfs_snapshot_nvl function.

Remove the logging of the "release" operation in
dsl_dataset_user_release_sync().  The logging caused a null dereference
because ds->ds_dir is zeroed in dsl_dataset_destroy_sync() and the
logging functions try to get the ds name via the dsl_dataset_name()
function. I've got no idea why this particular code would have worked
in Illumos.  This code has subsequently been completely reworked in
Illumos commit 3b2aab1 (3464 zfs synctask code needs restructuring).

Squash some "may be used uninitialized" warning/erorrs.

Fix some printf format warnings for %lld and %llu.

Apply a few spa_writeable() changes that were made to Illumos in
illumos/illumos-gate.git@cd1c8b8 as part of the 3112, 3113, 3114 and
3115 fixes.

Add a missing call to fnvlist_free(nvl) in log_internal() that was added
in Illumos to fix issue 3085 but couldn't be ported to ZoL at the time
(zfsonlinux/zfs@9e11c73) because it depended on future work.

1 files changed, 198 insertions, 174 deletions

diff --git a/lib/libzfs/libzfs_dataset.c b/lib/libzfs/libzfs_dataset.c
index 244b687ed..041750bca 100644
--- a/lib/libzfs/libzfs_dataset.c
+++ b/lib/libzfs/libzfs_dataset.c
@@ -313,7 +313,7 @@ get_recvd_props_ioctl(zfs_handle_t *zhp)
 {
 	libzfs_handle_t *hdl = zhp->zfs_hdl;
 	nvlist_t *recvdprops;
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
+	zfs_cmd_t zc = {"\0", 0, 0, 0, 0, 0, 0, 0, "\0", "\0", "\0"};
 	int err;
 
 	if (zcmd_alloc_dst_nvlist(hdl, &zc, 0) != 0)
@@ -376,7 +376,7 @@ static int
 get_stats(zfs_handle_t *zhp)
 {
 	int rc = 0;
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
+	zfs_cmd_t zc = {"\0", 0, 0, 0, 0, 0, 0, 0, "\0", "\0", "\0"};
 
 	if (zcmd_alloc_dst_nvlist(zhp->zfs_hdl, &zc, 0) != 0)
 		return (-1);
@@ -439,7 +439,7 @@ make_dataset_handle_common(zfs_handle_t *zhp, zfs_cmd_t *zc)
 zfs_handle_t *
 make_dataset_handle(libzfs_handle_t *hdl, const char *path)
 {
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
+	zfs_cmd_t zc = {"\0", 0, 0, 0, 0, 0, 0, 0, "\0", "\0", "\0"};
 
 	zfs_handle_t *zhp = calloc(sizeof (zfs_handle_t), 1);
 
@@ -1427,15 +1427,14 @@ zfs_is_namespace_prop(zfs_prop_t prop)
 int
 zfs_prop_set(zfs_handle_t *zhp, const char *propname, const char *propval)
 {
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
+	zfs_cmd_t zc = {"\0", 0, 0, 0, 0, 0, 0, 0, "\0", "\0", "\0"};
 	int ret = -1;
 	prop_changelist_t *cl = NULL;
 	char errbuf[1024];
 	libzfs_handle_t *hdl = zhp->zfs_hdl;
 	nvlist_t *nvl = NULL, *realprops;
 	zfs_prop_t prop;
-	boolean_t do_prefix;
-	uint64_t idx;
+	boolean_t do_prefix = B_TRUE;
 	int added_resv = 0;
 
 	(void) snprintf(errbuf, sizeof (errbuf),
@@ -1474,12 +1473,17 @@ zfs_prop_set(zfs_handle_t *zhp, const char *propname, const char *propval)
 	}
 
 	/*
-	 * If the dataset's canmount property is being set to noauto,
-	 * then we want to prevent unmounting & remounting it.
+	 * We don't want to unmount & remount the dataset when changing
+	 * its canmount property to 'on' or 'noauto'.  We only use
+	 * the changelist logic to unmount when setting canmount=off.
 	 */
-	do_prefix = !((prop == ZFS_PROP_CANMOUNT) &&
-	    (zprop_string_to_index(prop, propval, &idx,
-	    ZFS_TYPE_DATASET) == 0) && (idx == ZFS_CANMOUNT_NOAUTO));
+	if (prop == ZFS_PROP_CANMOUNT) {
+		uint64_t idx;
+		int err = zprop_string_to_index(prop, propval, &idx,
+		    ZFS_TYPE_DATASET);
+		if (err == 0 && idx != ZFS_CANMOUNT_OFF)
+			do_prefix = B_FALSE;
+	}
 
 	if (do_prefix && (ret = changelist_prefix(cl)) != 0)
 		goto error;
@@ -1549,7 +1553,7 @@ error:
 int
 zfs_prop_inherit(zfs_handle_t *zhp, const char *propname, boolean_t received)
 {
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
+	zfs_cmd_t zc = {"\0", 0, 0, 0, 0, 0, 0, 0, "\0", "\0", "\0"};
 	int ret;
 	prop_changelist_t *cl;
 	libzfs_handle_t *hdl = zhp->zfs_hdl;
@@ -1724,7 +1728,7 @@ static int
 get_numeric_property(zfs_handle_t *zhp, zfs_prop_t prop, zprop_source_t *src,
     char **source, uint64_t *val)
 {
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
+	zfs_cmd_t zc = {"\0", 0, 0, 0, 0, 0, 0, 0, "\0", "\0", "\0"};
 	nvlist_t *zplprops = NULL;
 	struct mnttab mnt;
 	char *mntopt_on = NULL;
@@ -2576,7 +2580,7 @@ zfs_prop_get_userquota_common(zfs_handle_t *zhp, const char *propname,
     uint64_t *propvalue, zfs_userquota_prop_t *typep)
 {
 	int err;
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
+	zfs_cmd_t zc = {"\0", 0, 0, 0, 0, 0, 0, 0, "\0", "\0", "\0"};
 
 	(void) strlcpy(zc.zc_name, zhp->zfs_name, sizeof (zc.zc_name));
 
@@ -2636,7 +2640,7 @@ zfs_prop_get_written_int(zfs_handle_t *zhp, const char *propname,
     uint64_t *propvalue)
 {
 	int err;
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
+	zfs_cmd_t zc = {"\0", 0, 0, 0, 0, 0, 0, 0, "\0", "\0", "\0"};
 	const char *snapname;
 
 	(void) strlcpy(zc.zc_name, zhp->zfs_name, sizeof (zc.zc_name));
@@ -2686,25 +2690,6 @@ zfs_prop_get_written(zfs_handle_t *zhp, const char *propname,
 	return (0);
 }
 
-int
-zfs_get_snapused_int(zfs_handle_t *firstsnap, zfs_handle_t *lastsnap,
-    uint64_t *usedp)
-{
-	int err;
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
-
-	(void) strlcpy(zc.zc_name, lastsnap->zfs_name, sizeof (zc.zc_name));
-	(void) strlcpy(zc.zc_value, firstsnap->zfs_name, sizeof (zc.zc_value));
-
-	err = ioctl(lastsnap->zfs_hdl->libzfs_fd, ZFS_IOC_SPACE_SNAPS, &zc);
-	if (err)
-		return (err);
-
-	*usedp = zc.zc_cookie;
-
-	return (0);
-}
-
 /*
  * Returns the name of the given zfs handle.
  */
@@ -2775,7 +2760,7 @@ static int
 check_parents(libzfs_handle_t *hdl, const char *path, uint64_t *zoned,
     boolean_t accept_ancestor, int *prefixlen)
 {
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
+	zfs_cmd_t zc = {"\0", 0, 0, 0, 0, 0, 0, 0, "\0", "\0", "\0"};
 	char parent[ZFS_MAXNAMELEN];
 	char *slash;
 	zfs_handle_t *zhp;
@@ -2905,7 +2890,6 @@ create_parents(libzfs_handle_t *hdl, char *target, int prefixlen)
 	 */
 	for (cp = target + prefixlen + 1;
 	    (cp = strchr(cp, '/')); *cp = '/', cp++) {
-		char *logstr;
 
 		*cp = '\0';
 
@@ -2916,16 +2900,12 @@ create_parents(libzfs_handle_t *hdl, char *target, int prefixlen)
 			continue;
 		}
 
-		logstr = hdl->libzfs_log_str;
-		hdl->libzfs_log_str = NULL;
 		if (zfs_create(hdl, target, ZFS_TYPE_FILESYSTEM,
 		    NULL) != 0) {
-			hdl->libzfs_log_str = logstr;
 			opname = dgettext(TEXT_DOMAIN, "create");
 			goto ancestorerr;
 		}
 
-		hdl->libzfs_log_str = logstr;
 		h = zfs_open(hdl, target, ZFS_TYPE_FILESYSTEM);
 		if (h == NULL) {
 			opname = dgettext(TEXT_DOMAIN, "open");
@@ -2983,12 +2963,12 @@ int
 zfs_create(libzfs_handle_t *hdl, const char *path, zfs_type_t type,
     nvlist_t *props)
 {
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
 	int ret;
 	uint64_t size = 0;
 	uint64_t blocksize = zfs_prop_default_numeric(ZFS_PROP_VOLBLOCKSIZE);
 	char errbuf[1024];
 	uint64_t zoned;
+	dmu_objset_type_t ost;
 
 	(void) snprintf(errbuf, sizeof (errbuf), dgettext(TEXT_DOMAIN,
 	    "cannot create '%s'"), path);
@@ -3008,17 +2988,16 @@ zfs_create(libzfs_handle_t *hdl, const char *path, zfs_type_t type,
 	 * will return ENOENT, not EEXIST.  To prevent this from happening, we
 	 * first try to see if the dataset exists.
 	 */
-	(void) strlcpy(zc.zc_name, path, sizeof (zc.zc_name));
-	if (zfs_dataset_exists(hdl, zc.zc_name, ZFS_TYPE_DATASET)) {
+	if (zfs_dataset_exists(hdl, path, ZFS_TYPE_DATASET)) {
 		zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 		    "dataset already exists"));
 		return (zfs_error(hdl, EZFS_EXISTS, errbuf));
 	}
 
 	if (type == ZFS_TYPE_VOLUME)
-		zc.zc_objset_type = DMU_OST_ZVOL;
+		ost = DMU_OST_ZVOL;
 	else
-		zc.zc_objset_type = DMU_OST_ZFS;
+		ost = DMU_OST_ZFS;
 
 	if (props && (props = zfs_valid_proplist(hdl, type, props,
 	    zoned, NULL, errbuf)) == 0)
@@ -3070,12 +3049,9 @@ zfs_create(libzfs_handle_t *hdl, const char *path, zfs_type_t type,
 		}
 	}
 
-	if (props && zcmd_write_src_nvlist(hdl, &zc, props) != 0)
-		return (-1);
-	nvlist_free(props);
-
 	/* create the dataset */
-	ret = zfs_ioctl(hdl, ZFS_IOC_CREATE, &zc);
+	ret = lzc_create(path, ost, props);
+	nvlist_free(props);
 
 	if (ret == 0 && type == ZFS_TYPE_VOLUME) {
 		ret = zvol_create_link(hdl, path);
@@ -3084,13 +3060,10 @@ zfs_create(libzfs_handle_t *hdl, const char *path, zfs_type_t type,
 			    dgettext(TEXT_DOMAIN,
 			    "Volume successfully created, but device links "
 			    "were not created"));
-			zcmd_free_nvlists(&zc);
 			return (-1);
 		}
 	}
 
-	zcmd_free_nvlists(&zc);
-
 	/* check for failure */
 	if (ret != 0) {
 		char parent[ZFS_MAXNAMELEN];
@@ -3147,7 +3120,7 @@ zfs_create(libzfs_handle_t *hdl, const char *path, zfs_type_t type,
 int
 zfs_destroy(zfs_handle_t *zhp, boolean_t defer)
 {
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
+	zfs_cmd_t zc = {"\0", 0, 0, 0, 0, 0, 0, 0, "\0", "\0", "\0"};
 
 	(void) strlcpy(zc.zc_name, zhp->zfs_name, sizeof (zc.zc_name));
 
@@ -3241,33 +3214,36 @@ int
 zfs_destroy_snaps_nvl(zfs_handle_t *zhp, nvlist_t *snaps, boolean_t defer)
 {
 	int ret;
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
+	nvlist_t *errlist;
 
-	(void) strlcpy(zc.zc_name, zhp->zfs_name, sizeof (zc.zc_name));
-	if (zcmd_write_src_nvlist(zhp->zfs_hdl, &zc, snaps) != 0)
-		return (-1);
-	zc.zc_defer_destroy = defer;
+	ret = lzc_destroy_snaps(snaps, defer, &errlist);
 
-	ret = zfs_ioctl(zhp->zfs_hdl, ZFS_IOC_DESTROY_SNAPS_NVL, &zc);
 	if (ret != 0) {
-		char errbuf[1024];
-
-		(void) snprintf(errbuf, sizeof (errbuf), dgettext(TEXT_DOMAIN,
-		    "cannot destroy snapshots in %s"), zc.zc_name);
-
-		switch (errno) {
-		case EEXIST:
-			zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
-			    "snapshot is cloned"));
-			return (zfs_error(zhp->zfs_hdl, EZFS_EXISTS, errbuf));
+		nvpair_t *pair;
+		for (pair = nvlist_next_nvpair(errlist, NULL);
+		    pair != NULL; pair = nvlist_next_nvpair(errlist, pair)) {
+			char errbuf[1024];
+			(void) snprintf(errbuf, sizeof (errbuf),
+			    dgettext(TEXT_DOMAIN, "cannot destroy snapshot %s"),
+			    nvpair_name(pair));
 
-		default:
-			return (zfs_standard_error(zhp->zfs_hdl, errno,
-			    errbuf));
+			switch (fnvpair_value_int32(pair)) {
+			case EEXIST:
+				zfs_error_aux(zhp->zfs_hdl,
+				    dgettext(TEXT_DOMAIN,
+				    "snapshot is cloned"));
+				ret = zfs_error(zhp->zfs_hdl, EZFS_EXISTS,
+				    errbuf);
+				break;
+			default:
+				ret = zfs_standard_error(zhp->zfs_hdl, errno,
+				    errbuf);
+				break;
+			}
 		}
 	}
 
-	return (0);
+	return (ret);
 }
 
 /*
@@ -3276,12 +3252,10 @@ zfs_destroy_snaps_nvl(zfs_handle_t *zhp, nvlist_t *snaps, boolean_t defer)
 int
 zfs_clone(zfs_handle_t *zhp, const char *target, nvlist_t *props)
 {
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
 	char parent[ZFS_MAXNAMELEN];
 	int ret;
 	char errbuf[1024];
 	libzfs_handle_t *hdl = zhp->zfs_hdl;
-	zfs_type_t type;
 	uint64_t zoned;
 
 	assert(zhp->zfs_type == ZFS_TYPE_SNAPSHOT);
@@ -3300,32 +3274,21 @@ zfs_clone(zfs_handle_t *zhp, const char *target, nvlist_t *props)
 	(void) parent_name(target, parent, sizeof (parent));
 
 	/* do the clone */
-	if (ZFS_IS_VOLUME(zhp)) {
-		zc.zc_objset_type = DMU_OST_ZVOL;
-		type = ZFS_TYPE_VOLUME;
-	} else {
-		zc.zc_objset_type = DMU_OST_ZFS;
-		type = ZFS_TYPE_FILESYSTEM;
-	}
 
 	if (props) {
+		zfs_type_t type;
+		if (ZFS_IS_VOLUME(zhp)) {
+			type = ZFS_TYPE_VOLUME;
+		} else {
+			type = ZFS_TYPE_FILESYSTEM;
+		}
 		if ((props = zfs_valid_proplist(hdl, type, props, zoned,
 		    zhp, errbuf)) == NULL)
 			return (-1);
-
-		if (zcmd_write_src_nvlist(hdl, &zc, props) != 0) {
-			nvlist_free(props);
-			return (-1);
-		}
-
-		nvlist_free(props);
 	}
 
-	(void) strlcpy(zc.zc_name, target, sizeof (zc.zc_name));
-	(void) strlcpy(zc.zc_value, zhp->zfs_name, sizeof (zc.zc_value));
-	ret = zfs_ioctl(zhp->zfs_hdl, ZFS_IOC_CREATE, &zc);
-
-	zcmd_free_nvlists(&zc);
+	ret = lzc_clone(target, zhp->zfs_name, props);
+	nvlist_free(props);
 
 	if (ret != 0) {
 		switch (errno) {
@@ -3425,7 +3388,7 @@ int
 zfs_promote(zfs_handle_t *zhp)
 {
 	libzfs_handle_t *hdl = zhp->zfs_hdl;
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
+	zfs_cmd_t zc = {"\0", 0, 0, 0, 0, 0, 0, 0, "\0", "\0", "\0"};
 	char parent[MAXPATHLEN];
 	char *cp;
 	int ret;
@@ -3540,94 +3503,159 @@ zfs_create_link_cb(zfs_handle_t *zhp, void *arg)
 	return (ret);
 }
 
+typedef struct snapdata {
+	nvlist_t *sd_nvl;
+	const char *sd_snapname;
+} snapdata_t;
+
+static int
+zfs_snapshot_cb(zfs_handle_t *zhp, void *arg)
+{
+	snapdata_t *sd = arg;
+	char name[ZFS_MAXNAMELEN];
+	int rv = 0;
+
+	(void) snprintf(name, sizeof (name),
+	    "%s@%s", zfs_get_name(zhp), sd->sd_snapname);
+
+	fnvlist_add_boolean(sd->sd_nvl, name);
+
+	rv = zfs_iter_filesystems(zhp, zfs_snapshot_cb, sd);
+	zfs_close(zhp);
+	return (rv);
+}
+
 /*
- * Takes a snapshot of the given dataset.
+ * Creates snapshots.  The keys in the snaps nvlist are the snapshots to be
+ * created.
  */
 int
-zfs_snapshot(libzfs_handle_t *hdl, const char *path, boolean_t recursive,
-    nvlist_t *props)
+zfs_snapshot_nvl(libzfs_handle_t *hdl, nvlist_t *snaps, nvlist_t *props)
 {
-	const char *delim;
-	char parent[ZFS_MAXNAMELEN];
-	zfs_handle_t *zhp;
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
 	int ret;
 	char errbuf[1024];
+	nvpair_t *elem;
+	nvlist_t *errors;
 
 	(void) snprintf(errbuf, sizeof (errbuf), dgettext(TEXT_DOMAIN,
-	    "cannot snapshot '%s'"), path);
-
-	/* validate the target name */
-	if (!zfs_validate_name(hdl, path, ZFS_TYPE_SNAPSHOT, B_TRUE))
-		return (zfs_error(hdl, EZFS_INVALIDNAME, errbuf));
+	    "cannot create snapshots "));
 
-	if (props) {
-		if ((props = zfs_valid_proplist(hdl, ZFS_TYPE_SNAPSHOT,
-		    props, B_FALSE, NULL, errbuf)) == NULL)
-			return (-1);
+	elem = NULL;
+	while ((elem = nvlist_next_nvpair(snaps, elem)) != NULL) {
+		const char *snapname = nvpair_name(elem);
 
-		if (zcmd_write_src_nvlist(hdl, &zc, props) != 0) {
-			nvlist_free(props);
-			return (-1);
+		/* validate the target name */
+		if (!zfs_validate_name(hdl, snapname, ZFS_TYPE_SNAPSHOT,
+		    B_TRUE)) {
+			(void) snprintf(errbuf, sizeof (errbuf),
+			    dgettext(TEXT_DOMAIN,
+			    "cannot create snapshot '%s'"), snapname);
+			return (zfs_error(hdl, EZFS_INVALIDNAME, errbuf));
 		}
-
-		nvlist_free(props);
 	}
 
-	/* make sure the parent exists and is of the appropriate type */
-	delim = strchr(path, '@');
-	(void) strncpy(parent, path, delim - path);
-	parent[delim - path] = '\0';
-
-	if ((zhp = zfs_open(hdl, parent, ZFS_TYPE_FILESYSTEM |
-	    ZFS_TYPE_VOLUME)) == NULL) {
-		zcmd_free_nvlists(&zc);
+	if (props != NULL &&
+	    (props = zfs_valid_proplist(hdl, ZFS_TYPE_SNAPSHOT,
+	    props, B_FALSE, NULL, errbuf)) == NULL) {
 		return (-1);
 	}
 
-	(void) strlcpy(zc.zc_name, zhp->zfs_name, sizeof (zc.zc_name));
-	(void) strlcpy(zc.zc_value, delim+1, sizeof (zc.zc_value));
-	if (ZFS_IS_VOLUME(zhp))
-		zc.zc_objset_type = DMU_OST_ZVOL;
-	else
-		zc.zc_objset_type = DMU_OST_ZFS;
-	zc.zc_cookie = recursive;
-	ret = zfs_ioctl(zhp->zfs_hdl, ZFS_IOC_SNAPSHOT, &zc);
+	ret = lzc_snapshot(snaps, props, &errors);
 
-	zcmd_free_nvlists(&zc);
+	if (ret != 0) {
+		boolean_t printed = B_FALSE;
+		for (elem = nvlist_next_nvpair(errors, NULL);
+		    elem != NULL;
+		    elem = nvlist_next_nvpair(errors, elem)) {
+			(void) snprintf(errbuf, sizeof (errbuf),
+			    dgettext(TEXT_DOMAIN,
+			    "cannot create snapshot '%s'"), nvpair_name(elem));
+			(void) zfs_standard_error(hdl,
+			    fnvpair_value_int32(elem), errbuf);
+			printed = B_TRUE;
+		}
+		if (!printed) {
+			switch (ret) {
+			case EXDEV:
+				zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
+				    "multiple snapshots of same "
+				    "fs not allowed"));
+				(void) zfs_error(hdl, EZFS_EXISTS, errbuf);
 
-	/*
-	 * if it was recursive, the one that actually failed will be in
-	 * zc.zc_name.
-	 */
-	if (ret != 0)
-		(void) snprintf(errbuf, sizeof (errbuf), dgettext(TEXT_DOMAIN,
-		    "cannot create snapshot '%s@%s'"), zc.zc_name, zc.zc_value);
+				break;
+			default:
+				(void) zfs_standard_error(hdl, ret, errbuf);
+			}
+		}
+	} else {
+		zfs_handle_t *zhp;
+		int linktries = 0, linkok = 0, linkfail = 0;
+		nvpair_t *snap;
 
-	if (ret == 0 && recursive) {
-		struct createdata cd;
+		for (snap = nvlist_next_nvpair(snaps, NULL); snap != NULL;
+		    snap = nvlist_next_nvpair(snaps, snap)) {
+			char *cp, *snapname;
 
-		cd.cd_snapname = delim + 1;
-		cd.cd_ifexists = B_FALSE;
-		(void) zfs_iter_filesystems(zhp, zfs_create_link_cb, &cd);
-	}
-	if (ret == 0 && zhp->zfs_type == ZFS_TYPE_VOLUME) {
-		ret = zvol_create_link(zhp->zfs_hdl, path);
-		if (ret != 0) {
-			(void) zfs_standard_error(hdl, errno,
-			    dgettext(TEXT_DOMAIN,
-			    "Volume successfully snapshotted, but device links "
-			    "were not created"));
-			zfs_close(zhp);
-			return (-1);
+			snapname = nvpair_name(snap);
+			cp = strchr(snapname, '@');
+			*cp = '\0';
+
+			if ((zhp = zfs_open(hdl, snapname, ZFS_TYPE_FILESYSTEM |
+				ZFS_TYPE_VOLUME)) != NULL) {
+				if (zhp->zfs_type == ZFS_TYPE_VOLUME) {
+					++linktries;
+					*cp = '@';
+					if (zvol_create_link(zhp->zfs_hdl, nvpair_name(snap)))
+						++linkfail;
+					else
+						++linkok;
+				}
+			}
 		}
 	}
 
-	if (ret != 0)
-		(void) zfs_standard_error(hdl, errno, errbuf);
+	nvlist_free(props);
+	nvlist_free(errors);
+	return (ret);
+}
 
-	zfs_close(zhp);
+int
+zfs_snapshot(libzfs_handle_t *hdl, const char *path, boolean_t recursive,
+    nvlist_t *props)
+{
+	int ret;
+	snapdata_t sd = { 0 };
+	char fsname[ZFS_MAXNAMELEN];
+	char *cp;
+	zfs_handle_t *zhp;
+	char errbuf[1024];
+
+	(void) snprintf(errbuf, sizeof (errbuf), dgettext(TEXT_DOMAIN,
+	    "cannot snapshot %s"), path);
+
+	if (!zfs_validate_name(hdl, path, ZFS_TYPE_SNAPSHOT, B_TRUE))
+		return (zfs_error(hdl, EZFS_INVALIDNAME, errbuf));
+ 
+	(void) strlcpy(fsname, path, sizeof (fsname));
+	cp = strchr(fsname, '@');
+	*cp = '\0';
+	sd.sd_snapname = cp + 1;
 
+	if ((zhp = zfs_open(hdl, fsname, ZFS_TYPE_FILESYSTEM |
+	    ZFS_TYPE_VOLUME)) == NULL) {
+		return (-1);
+	}
+
+	verify(nvlist_alloc(&sd.sd_nvl, NV_UNIQUE_NAME, 0) == 0);
+	if (recursive) {
+		(void) zfs_snapshot_cb(zfs_handle_dup(zhp), &sd);
+	} else {
+		fnvlist_add_boolean(sd.sd_nvl, path);
+	}
+
+	ret = zfs_snapshot_nvl(hdl, sd.sd_nvl, props);
+	nvlist_free(sd.sd_nvl);
+	zfs_close(zhp);
 	return (ret);
 }
 
@@ -3655,17 +3683,13 @@ rollback_destroy(zfs_handle_t *zhp, void *data)
 		    zfs_get_type(zhp) == ZFS_TYPE_SNAPSHOT &&
 		    zfs_prop_get_int(zhp, ZFS_PROP_CREATETXG) >
 		    cbp->cb_create) {
-			char *logstr;
 
 			cbp->cb_dependent = B_TRUE;
 			cbp->cb_error |= zfs_iter_dependents(zhp, B_FALSE,
 			    rollback_destroy, cbp);
 			cbp->cb_dependent = B_FALSE;
 
-			logstr = zhp->zfs_hdl->libzfs_log_str;
-			zhp->zfs_hdl->libzfs_log_str = NULL;
 			cbp->cb_error |= zfs_destroy(zhp, B_FALSE);
-			zhp->zfs_hdl->libzfs_log_str = logstr;
 		}
 	} else {
 		/* We must destroy this clone; first unmount it */
@@ -3702,7 +3726,7 @@ zfs_rollback(zfs_handle_t *zhp, zfs_handle_t *snap, boolean_t force)
 {
 	rollback_data_t cb = { 0 };
 	int err;
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
+	zfs_cmd_t zc = {"\0", 0, 0, 0, 0, 0, 0, 0, "\0", "\0", "\0"};
 	boolean_t restore_resv = 0;
 	uint64_t old_volsize = 0, new_volsize;
 	zfs_prop_t resv_prop = { 0 };
@@ -3789,7 +3813,7 @@ zfs_rename(zfs_handle_t *zhp, const char *target, boolean_t recursive,
     boolean_t force_unmount)
 {
 	int ret;
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
+	zfs_cmd_t zc = {"\0", 0, 0, 0, 0, 0, 0, 0, "\0", "\0", "\0"};
 	char *delim;
 	prop_changelist_t *cl = NULL;
 	zfs_handle_t *zhrp = NULL;
@@ -4008,7 +4032,7 @@ zvol_create_link(libzfs_handle_t *hdl, const char *dataset)
 static int
 zvol_create_link_common(libzfs_handle_t *hdl, const char *dataset, int ifexists)
 {
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
+	zfs_cmd_t zc = {"\0", 0, 0, 0, 0, 0, 0, 0, "\0", "\0", "\0"};
 	char path[MAXPATHLEN];
 	int error;
 
@@ -4072,7 +4096,7 @@ zvol_create_link_common(libzfs_handle_t *hdl, const char *dataset, int ifexists)
 int
 zvol_remove_link(libzfs_handle_t *hdl, const char *dataset)
 {
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
+	zfs_cmd_t zc = {"\0", 0, 0, 0, 0, 0, 0, 0, "\0", "\0", "\0"};
 	int timeout = 3000; /* in milliseconds */
 	int error = 0;
 	int i;
@@ -4265,7 +4289,7 @@ static int
 zfs_smb_acl_mgmt(libzfs_handle_t *hdl, char *dataset, char *path,
     zfs_smb_acl_op_t cmd, char *resource1, char *resource2)
 {
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
+	zfs_cmd_t zc = {"\0", 0, 0, 0, 0, 0, 0, 0, "\0", "\0", "\0"};
 	nvlist_t *nvlist = NULL;
 	int error;
 
@@ -4347,7 +4371,7 @@ int
 zfs_userspace(zfs_handle_t *zhp, zfs_userquota_prop_t type,
     zfs_userspace_cb_t func, void *arg)
 {
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
+	zfs_cmd_t zc = {"\0", 0, 0, 0, 0, 0, 0, 0, "\0", "\0", "\0"};
 	zfs_useracct_t buf[100];
 	libzfs_handle_t *hdl = zhp->zfs_hdl;
 	int ret;
@@ -4389,7 +4413,7 @@ zfs_hold(zfs_handle_t *zhp, const char *snapname, const char *tag,
     boolean_t recursive, boolean_t temphold, boolean_t enoent_ok,
     int cleanup_fd, uint64_t dsobj, uint64_t createtxg)
 {
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
+	zfs_cmd_t zc = {"\0", 0, 0, 0, 0, 0, 0, 0, "\0", "\0", "\0"};
 	libzfs_handle_t *hdl = zhp->zfs_hdl;
 
 	ASSERT(!recursive || dsobj == 0);
@@ -4447,7 +4471,7 @@ int
 zfs_release(zfs_handle_t *zhp, const char *snapname, const char *tag,
     boolean_t recursive)
 {
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
+	zfs_cmd_t zc = {"\0", 0, 0, 0, 0, 0, 0, 0, "\0", "\0", "\0"};
 	libzfs_handle_t *hdl = zhp->zfs_hdl;
 
 	(void) strlcpy(zc.zc_name, zhp->zfs_name, sizeof (zc.zc_name));
@@ -4487,7 +4511,7 @@ zfs_release(zfs_handle_t *zhp, const char *snapname, const char *tag,
 int
 zfs_get_fsacl(zfs_handle_t *zhp, nvlist_t **nvl)
 {
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
+	zfs_cmd_t zc = {"\0", 0, 0, 0, 0, 0, 0, 0, "\0", "\0", "\0"};
 	libzfs_handle_t *hdl = zhp->zfs_hdl;
 	int nvsz = 2048;
 	void *nvbuf;
@@ -4554,7 +4578,7 @@ out:
 int
 zfs_set_fsacl(zfs_handle_t *zhp, boolean_t un, nvlist_t *nvl)
 {
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
+	zfs_cmd_t zc = {"\0", 0, 0, 0, 0, 0, 0, 0, "\0", "\0", "\0"};
 	libzfs_handle_t *hdl = zhp->zfs_hdl;
 	char *nvbuf;
 	char errbuf[ZFS_MAXNAMELEN+32];
@@ -4608,7 +4632,7 @@ zfs_set_fsacl(zfs_handle_t *zhp, boolean_t un, nvlist_t *nvl)
 int
 zfs_get_holds(zfs_handle_t *zhp, nvlist_t **nvl)
 {
-	zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
+	zfs_cmd_t zc = {"\0", 0, 0, 0, 0, 0, 0, 0, "\0", "\0", "\0"};
 	libzfs_handle_t *hdl = zhp->zfs_hdl;
 	int nvsz = 2048;
 	void *nvbuf;