MFV r354377: 10554 Implemented zpool sync command

illumos/illumos-gate@9c2acf00e275b6b2125a306f33cdddcc58393220
https://github.com/illumos/illumos-gate/commit/9c2acf00e275b6b2125a306f33cdddcc58393220

https://www.illumos.org/issues/10554
  During the port of MMP (illumos bug 10499) from ZoL, I found this
  earlier ZoL project is a prerequisite. Here is the original
  description.  This addition will enable us to sync an open TXG to the
  main pool on demand. The functionality is similar to 'sync(2)' but
  'zpool sync' will return when data has hit the main storage instead of
  potentially just the ZIL as is the case with the 'sync(2)' cmd.

Portions contributed by: Jerry Jelinek <jerry.jelinek@joyent.com>
Author: Alek Pinchuk <apinchuk@datto.com>
MFC after:	3 weeks
Relnotes:	possibly

4 files changed, 49 insertions, 11 deletions

diff --git a/cddl/contrib/opensolaris/lib/libzfs/common/libzfs.h b/cddl/contrib/opensolaris/lib/libzfs/common/libzfs.h
index c0e235476fed..aeae6e3822a3 100644
--- a/cddl/contrib/opensolaris/lib/libzfs/common/libzfs.h
+++ b/cddl/contrib/opensolaris/lib/libzfs/common/libzfs.h
@@ -271,6 +271,8 @@ extern int zpool_clear(zpool_handle_t *, const char *, nvlist_t *);
 extern int zpool_reguid(zpool_handle_t *);
 extern int zpool_reopen(zpool_handle_t *);
 
+extern int zpool_sync_one(zpool_handle_t *, void *);
+
 extern int zpool_vdev_online(zpool_handle_t *, const char *, int,
     vdev_state_t *);
 extern int zpool_vdev_offline(zpool_handle_t *, const char *, boolean_t);
diff --git a/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_pool.c b/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_pool.c
index dfb2198b7c75..153fda241188 100644
--- a/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_pool.c
+++ b/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_pool.c
@@ -3515,6 +3515,27 @@ zpool_reopen(zpool_handle_t *zhp)
 	return (zpool_standard_error(hdl, errno, msg));
 }
 
+/* call into libzfs_core to execute the sync IOCTL per pool */
+int
+zpool_sync_one(zpool_handle_t *zhp, void *data)
+{
+	int ret;
+	libzfs_handle_t *hdl = zpool_get_handle(zhp);
+	const char *pool_name = zpool_get_name(zhp);
+	boolean_t *force = data;
+	nvlist_t *innvl = fnvlist_alloc();
+
+	fnvlist_add_boolean_value(innvl, "force", *force);
+	if ((ret = lzc_sync(pool_name, innvl, NULL)) != 0) {
+		nvlist_free(innvl);
+		return (zpool_standard_error_fmt(hdl, ret,
+		    dgettext(TEXT_DOMAIN, "sync '%s' failed"), pool_name));
+	}
+	nvlist_free(innvl);
+
+	return (0);
+}
+
 /*
  * Convert from a devid string to a path.
  */
diff --git a/cddl/contrib/opensolaris/lib/libzfs_core/common/libzfs_core.c b/cddl/contrib/opensolaris/lib/libzfs_core/common/libzfs_core.c
index 4f5054fbd084..cd5767e69b9b 100644
--- a/cddl/contrib/opensolaris/lib/libzfs_core/common/libzfs_core.c
+++ b/cddl/contrib/opensolaris/lib/libzfs_core/common/libzfs_core.c
@@ -24,6 +24,7 @@
  * Copyright (c) 2013 Steven Hartland. All rights reserved.
  * Copyright (c) 2014 Integros [integros.com]
  * Copyright 2017 RackTop Systems.
+ * Copyright (c) 2017 Datto Inc.
  */
 
 /*
@@ -137,16 +138,17 @@ lzc_ioctl(zfs_ioc_t ioc, const char *name,
 {
 	zfs_cmd_t zc = { 0 };
 	int error = 0;
-	char *packed;
+	char *packed = NULL;
 #ifdef __FreeBSD__
 	nvlist_t *oldsource;
 #endif
-	size_t size;
+	size_t size = 0;
 
 	ASSERT3S(g_refcount, >, 0);
 	VERIFY3S(g_fd, !=, -1);
 
-	(void) strlcpy(zc.zc_name, name, sizeof (zc.zc_name));
+	if (name != NULL)
+		(void) strlcpy(zc.zc_name, name, sizeof (zc.zc_name));
 
 #ifdef __FreeBSD__
 	if (zfs_ioctl_version == ZFS_IOCVER_UNDEF)
@@ -160,9 +162,11 @@ lzc_ioctl(zfs_ioc_t ioc, const char *name,
 	}
 #endif
 
-	packed = fnvlist_pack(source, &size);
-	zc.zc_nvlist_src = (uint64_t)(uintptr_t)packed;
-	zc.zc_nvlist_src_size = size;
+	if (source != NULL) {
+		packed = fnvlist_pack(source, &size);
+		zc.zc_nvlist_src = (uint64_t)(uintptr_t)packed;
+		zc.zc_nvlist_src_size = size;
+	}
 
 	if (resultp != NULL) {
 		*resultp = NULL;
@@ -463,6 +467,18 @@ lzc_exists(const char *dataset)
 }
 
 /*
+ * outnvl is unused.
+ * It was added to preserve the function signature in case it is
+ * needed in the future.
+ */
+/*ARGSUSED*/
+int
+lzc_sync(const char *pool_name, nvlist_t *innvl, nvlist_t **outnvl)
+{
+	return (lzc_ioctl(ZFS_IOC_POOL_SYNC, pool_name, innvl, NULL));
+}
+
+/*
  * Create "user holds" on snapshots.  If there is a hold on a snapshot,
  * the snapshot can not be destroyed.  (However, it can be marked for deletion
  * by lzc_destroy_snaps(defer=B_TRUE).)
@@ -562,11 +578,7 @@ lzc_release(nvlist_t *holds, nvlist_t **errlist)
 int
 lzc_get_holds(const char *snapname, nvlist_t **holdsp)
 {
-	int error;
-	nvlist_t *innvl = fnvlist_alloc();
-	error = lzc_ioctl(ZFS_IOC_GET_HOLDS, snapname, innvl, holdsp);
-	fnvlist_free(innvl);
-	return (error);
+	return (lzc_ioctl(ZFS_IOC_GET_HOLDS, snapname, NULL, holdsp));
 }
 
 /*
diff --git a/cddl/contrib/opensolaris/lib/libzfs_core/common/libzfs_core.h b/cddl/contrib/opensolaris/lib/libzfs_core/common/libzfs_core.h
index 44deb7af7be0..97d7ce81d8ab 100644
--- a/cddl/contrib/opensolaris/lib/libzfs_core/common/libzfs_core.h
+++ b/cddl/contrib/opensolaris/lib/libzfs_core/common/libzfs_core.h
@@ -23,6 +23,7 @@
  * Copyright (c) 2012, 2016 by Delphix. All rights reserved.
  * Copyright (c) 2013 by Martin Matuska <mm@FreeBSD.org>. All rights reserved.
  * Copyright 2017 RackTop Systems.
+ * Copyright (c) 2017 Datto Inc.
  */
 
 #ifndef	_LIBZFS_CORE_H
@@ -91,6 +92,8 @@ boolean_t lzc_exists(const char *);
 int lzc_rollback(const char *, char *, int);
 int lzc_rollback_to(const char *, const char *);
 
+int lzc_sync(const char *, nvlist_t *, nvlist_t **);
+
 int lzc_rename(const char *, const char *);
 int lzc_destroy(const char *);