lvmcache: reread vg if the lvmetad copy is staledev-dct-lvmetad-3

1 files changed, 72 insertions, 0 deletions

diff --git a/lib/cache/lvmetad.c b/lib/cache/lvmetad.c
index ccdf63a35..30ebd916c 100644
--- a/lib/cache/lvmetad.c
+++ b/lib/cache/lvmetad.c
@@ -34,6 +34,8 @@ static char *_lvmetad_token = NULL;
 static const char *_lvmetad_socket = NULL;
 static struct cmd_context *_lvmetad_cmd = NULL;
 
+static struct volume_group *lvmetad_pvscan_vg(struct cmd_context *cmd, struct volume_group *vg);
+
 void lvmetad_disconnect(void)
 {
 	if (_lvmetad_connected)
@@ -442,6 +444,15 @@ struct volume_group *lvmetad_vg_lookup(struct cmd_context *cmd, const char *vgna
 				pvl->pv->status |= MISSING_PV; /* probably missing */
 		}
 
+		/*
+		 * locking may have detected a newer vg version and
+		 * invalidated the cached vg.
+		 */
+		if (dm_config_find_node(reply.cft->root, "vg_invalid")) {
+			log_debug_lvmetad("Update invalid lvmetad cache for VG %s", vgname);
+			vg = lvmetad_pvscan_vg(cmd, vg);
+		}
+
 		lvmcache_update_vg(vg, 0);
 		vg_mark_partial_lvs(vg, 1);
 	}
@@ -902,6 +913,67 @@ static int _lvmetad_pvscan_single(struct metadata_area *mda, void *baton)
 	return 1;
 }
 
+/*
+ * The lock manager may detect that the vg cached in lvmetad is out of date,
+ * due to something like an lvcreate from another host.
+ * This is limited to changes that only affect the vg (not global state like
+ * orphan PVs), so we only need to reread mdas on the vg's existing pvs.
+ */
+
+static struct volume_group *lvmetad_pvscan_vg(struct cmd_context *cmd, struct volume_group *vg)
+{
+	struct volume_group *vg_ret = NULL;
+	struct pv_list *pvl;
+	struct device *dev;
+	struct label *label;
+	struct lvmcache_info *info;
+	struct _lvmetad_pvscan_baton baton;
+	/* Create a dummy instance. */
+	struct format_instance_ctx fic = { .type = 0 };
+
+	dm_list_iterate_items(pvl, &vg->pvs) {
+		/* missing pv */
+		if (!pvl->pv->dev)
+			continue;
+
+		dev = pvl->pv->dev;
+
+		if (!label_read(dev, &label, 0)) {
+			log_print_unless_silent("No PV label found on %s.", dev_name(dev));
+			continue;
+		}
+
+		info = (struct lvmcache_info *) label->info;
+
+		baton.vg = NULL;
+		baton.fid = lvmcache_fmt(info)->ops->create_instance(lvmcache_fmt(info), &fic);
+
+		if (!baton.fid)
+			return NULL;
+
+		if (baton.fid->fmt->features & FMT_OBSOLETE) {
+			log_error("WARNING: Ignoring obsolete format of metadata (%s) on device %s when using lvmetad",
+			  	baton.fid->fmt->name, dev_name(dev));
+			lvmcache_fmt(info)->ops->destroy_instance(baton.fid);
+			return NULL;
+		}
+
+		lvmcache_foreach_mda(info, _lvmetad_pvscan_single, &baton);
+
+		if (!baton.vg) {
+			lvmcache_fmt(info)->ops->destroy_instance(baton.fid);
+			return NULL;
+		}
+
+		if (!vg_ret)
+			vg_ret = baton.vg;
+		else
+			release_vg(baton.vg);
+	}
+
+	return vg_ret;
+}
+
 int lvmetad_pvscan_single(struct cmd_context *cmd, struct device *dev,
 			  activation_handler handler)
 {