MFC r308055: Add vdev_reopening support to vdev_geom.

It allows to avoid extra GEOM providers flapping without significant need.
Since GEOM got resize support, we don't need to reopen provider to get new
size.  If provider was orphaned and no longer valid, ZFS should already
know that, and in such case reopen should be done in full as expected.

1 files changed, 12 insertions, 1 deletions

diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_geom.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_geom.c
index e1fe202..5a78b9e 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_geom.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_geom.c
@@ -778,7 +778,14 @@ vdev_geom_open(vdev_t *vd, uint64_t *psize, uint64_t *max_psize,
 		return (EINVAL);
 	}
 
-	vd->vdev_tsd = NULL;
+	/*
+	 * Reopen the device if it's not currently open. Otherwise,
+	 * just update the physical size of the device.
+	 */
+	if ((cp = vd->vdev_tsd) != NULL) {
+		ASSERT(vd->vdev_reopening);
+		goto skip_open;
+	}
 
 	DROP_GIANT();
 	g_topology_lock();
@@ -863,6 +870,7 @@ vdev_geom_open(vdev_t *vd, uint64_t *psize, uint64_t *max_psize,
 		vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED;
 		return (error);
 	}
+skip_open:
 	pp = cp->provider;
 
 	/*
@@ -898,6 +906,9 @@ static void
 vdev_geom_close(vdev_t *vd)
 {
 
+	if (vd->vdev_reopening)
+		return;
+
 	DROP_GIANT();
 	g_topology_lock();
 	vdev_geom_close_locked(vd);