Illumos #2619 and #2747

2619 asynchronous destruction of ZFS file systems
2747 SPA versioning with zfs feature flags
Reviewed by: Matt Ahrens <[email protected]>
Reviewed by: George Wilson <[email protected]>
Reviewed by: Richard Lowe <[email protected]>
Reviewed by: Dan Kruchinin <[email protected]>
Approved by: Eric Schrock <[email protected]>

References:
  illumos/illumos-gate@53089ab7c84db6fb76c16ca50076c147cda11757
  illumos/illumos-gate@ad135b5d644628e791c3188a6ecbd9c257961ef8
  illumos changeset: 13700:2889e2596bd6
  https://www.illumos.org/issues/2619
  https://www.illumos.org/issues/2747

NOTE: The grub specific changes were not ported.  This change
must be made to the Linux grub packages.

Ported-by: Brian Behlendorf <[email protected]>

1 files changed, 35 insertions, 0 deletions

diff --git a/lib/libzfs/libzfs_config.c b/lib/libzfs/libzfs_config.c
index b36dee1e5..ee94fe106 100644
--- a/lib/libzfs/libzfs_config.c
+++ b/lib/libzfs/libzfs_config.c
@@ -18,12 +18,17 @@
  *
  * CDDL HEADER END
  */
+
 /*
  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  * Use is subject to license terms.
  */
 
 /*
+ * Copyright (c) 2012 by Delphix. All rights reserved.
+ */
+
+/*
  * The pool configuration repository is stored in /etc/zfs/zpool.cache as a
  * single packed nvlist.  While it would be nice to just read in this
  * file from userland, this wouldn't work from a local zone.  So we have to have
@@ -218,6 +223,36 @@ zpool_get_config(zpool_handle_t *zhp, nvlist_t **oldconfig)
 }
 
 /*
+ * Retrieves a list of enabled features and their refcounts and caches it in
+ * the pool handle.
+ */
+nvlist_t *
+zpool_get_features(zpool_handle_t *zhp)
+{
+	nvlist_t *config, *features;
+
+	config = zpool_get_config(zhp, NULL);
+
+	if (config == NULL || !nvlist_exists(config,
+	    ZPOOL_CONFIG_FEATURE_STATS)) {
+		int error;
+		boolean_t missing = B_FALSE;
+
+		error = zpool_refresh_stats(zhp, &missing);
+
+		if (error != 0 || missing)
+			return (NULL);
+
+		config = zpool_get_config(zhp, NULL);
+	}
+
+	verify(nvlist_lookup_nvlist(config, ZPOOL_CONFIG_FEATURE_STATS,
+	    &features) == 0);
+
+	return (features);
+}
+
+/*
  * Refresh the vdev statistics associated with the given pool.  This is used in
  * iostat to show configuration changes and determine the delta from the last
  * time the function was called.  This function can fail, in case the pool has