Added no_scrub_restart flag to zpool reopen

Added -n flag to zpool reopen that allows a running scrub
operation to continue if there is a device with Dirty Time Log.

By default if a component device has a DTL and zpool reopen
is executed all running scan operations will be restarted.

Added functional tests for `zpool reopen`

Tests covers following scenarios:
* `zpool reopen` without arguments,
* `zpool reopen` with pool name as argument,
* `zpool reopen` while scrubbing,
* `zpool reopen -n` while scrubbing,
* `zpool reopen -n` while resilvering,
* `zpool reopen` with bad arguments.

Reviewed-by: Brian Behlendorf <[email protected]>
Reviewed-by: Tom Caputi <[email protected]>
Signed-off-by: Arkadiusz Bubała <[email protected]>
Closes #6076 
Closes #6746 

2 files changed, 26 insertions, 11 deletions

diff --git a/lib/libzfs/libzfs_pool.c b/lib/libzfs/libzfs_pool.c
index bfb26d674..aa77b547a 100644
--- a/lib/libzfs/libzfs_pool.c
+++ b/lib/libzfs/libzfs_pool.c
@@ -25,6 +25,7 @@
  * Copyright (c) 2011, 2014 by Delphix. All rights reserved.
  * Copyright 2016 Igor Kozhukhov <[email protected]>
  * Copyright (c) 2017 Datto Inc.
+ * Copyright (c) 2017 Open-E, Inc. All Rights Reserved.
  */
 
 #include <ctype.h>
@@ -3370,20 +3371,20 @@ zpool_reguid(zpool_handle_t *zhp)
  * Reopen the pool.
  */
 int
-zpool_reopen(zpool_handle_t *zhp)
+zpool_reopen_one(zpool_handle_t *zhp, void *data)
 {
-	zfs_cmd_t zc = {"\0"};
-	char msg[1024];
-	libzfs_handle_t *hdl = zhp->zpool_hdl;
+	libzfs_handle_t *hdl = zpool_get_handle(zhp);
+	const char *pool_name = zpool_get_name(zhp);
+	boolean_t *scrub_restart = data;
+	int error;
 
-	(void) snprintf(msg, sizeof (msg),
-	    dgettext(TEXT_DOMAIN, "cannot reopen '%s'"),
-	    zhp->zpool_name);
+	error = lzc_reopen(pool_name, *scrub_restart);
+	if (error) {
+		return (zpool_standard_error_fmt(hdl, error,
+		    dgettext(TEXT_DOMAIN, "cannot reopen '%s'"), pool_name));
+	}
 
-	(void) strlcpy(zc.zc_name, zhp->zpool_name, sizeof (zc.zc_name));
-	if (zfs_ioctl(hdl, ZFS_IOC_POOL_REOPEN, &zc) == 0)
-		return (0);
-	return (zpool_standard_error(hdl, errno, msg));
+	return (0);
 }
 
 /* call into libzfs_core to execute the sync IOCTL per pool */
diff --git a/lib/libzfs_core/libzfs_core.c b/lib/libzfs_core/libzfs_core.c
index cc663f9dd..675f4a3de 100644
--- a/lib/libzfs_core/libzfs_core.c
+++ b/lib/libzfs_core/libzfs_core.c
@@ -24,6 +24,7 @@
  * Copyright (c) 2013 Steven Hartland. All rights reserved.
  * Copyright (c) 2017 Datto Inc.
  * Copyright 2017 RackTop Systems.
+ * Copyright (c) 2017 Open-E, Inc. All Rights Reserved.
  */
 
 /*
@@ -1111,3 +1112,16 @@ lzc_change_key(const char *fsname, uint64_t crypt_cmd, nvlist_t *props,
 	nvlist_free(ioc_args);
 	return (error);
 }
+
+int
+lzc_reopen(const char *pool_name, boolean_t scrub_restart)
+{
+	nvlist_t *args = fnvlist_alloc();
+	int error;
+
+	fnvlist_add_boolean_value(args, "scrub_restart", scrub_restart);
+
+	error = lzc_ioctl(ZFS_IOC_POOL_REOPEN, pool_name, args, NULL);
+	nvlist_free(args);
+	return (error);
+}