activation: use cmd pending mem for pending_delete

Since we need to preserve allocated strings across 2 separate
activation calls of '_tree_action()' we need to use other mem
pool them dm->mem - but since cmd->mem is released between
individual lvm2 locking calls, we rather introduce a new separate
mem pool just for pending deletes with easy to see life-span.
(not using 'libmem' as it would basicaly keep allocations over
the whole lifetime of clvmd)

This patch is fixing previous commmit where the memory was
improperly used after pool release.

lib/activate/dev_manager.c

@@ -64,7 +64,6 @@ struct dev_manager {
 	int activation;                 /* building activation tree */
 	int suspend;			/* building suspend tree */
 	unsigned track_external_lv_deps;
-	struct dm_list pending_delete;	/* str_list of dlid(s) with pending delete */
 	unsigned track_pending_delete;
 	unsigned track_pvmove_deps;
 
@@ -1387,8 +1386,6 @@ struct dev_manager *dev_manager_create(struct cmd_context *cmd,
 
 	dm_udev_set_sync_support(cmd->current_settings.udev_sync);
 
-	dm_list_init(&dm->pending_delete);
-
 	return dm;
 
       bad:
@@ -2165,7 +2162,7 @@ static int _add_dev_to_dtree(struct dev_manager *dm, struct dm_tree *dtree,
 	if (!(name = dm_build_dm_name(dm->mem, lv->vg->name, lv->name, layer)))
 		return_0;
 
-	if (!(dlid = build_dm_uuid(dm->mem, lv, layer)))
+	if (!(dlid = build_dm_uuid(dm->track_pending_delete ? dm->cmd->pending_delete_mem : dm->mem, lv, layer)))
 		return_0;
 
 	if (!_info(dm->cmd, name, dlid, 1, 0, &info, NULL, NULL))
@@ -2207,7 +2204,7 @@ static int _add_dev_to_dtree(struct dev_manager *dm, struct dm_tree *dtree,
 	if (info.exists && dm->track_pending_delete) {
 		log_debug_activation("Tracking pending delete for %s (%s).",
 				     display_lvname(lv), dlid);
-		if (!str_list_add(dm->mem, &dm->pending_delete, dlid))
+		if (!str_list_add(dm->cmd->pending_delete_mem, &dm->cmd->pending_delete, dlid))
 			return_0;
 	}
 
@@ -3599,20 +3596,26 @@ static int _clean_tree(struct dev_manager *dm, struct dm_tree_node *root, const
 		if (non_toplevel_tree_dlid && !strcmp(non_toplevel_tree_dlid, uuid))
 			continue;
 
-		if (!str_list_add(dm->mem, &dm->pending_delete, uuid))
+		if (!(uuid = dm_pool_strdup(dm->cmd->pending_delete_mem, uuid))) {
+			log_error("_clean_tree: Failed to duplicate uuid.");
+			return 0;
+		}
+
+		if (!str_list_add(dm->cmd->pending_delete_mem, &dm->cmd->pending_delete, uuid))
 			return_0;
 	}
 
 	/* Deactivate any tracked pending delete nodes */
-	if (!dm_list_empty(&dm->pending_delete) && !dm_get_suspended_counter()) {
+	if (!dm_list_empty(&dm->cmd->pending_delete) && !dm_get_suspended_counter()) {
 		fs_unlock();
 		dm_tree_set_cookie(root, fs_get_cookie());
-		dm_list_iterate_items(dl, &dm->pending_delete) {
+		dm_list_iterate_items(dl, &dm->cmd->pending_delete) {
 			log_debug_activation("Deleting tracked UUID %s.", dl->str);
 			if (!dm_tree_deactivate_children(root, dl->str, strlen(dl->str)))
 				return_0;
 		}
-		dm_list_init(&dm->pending_delete);
+		dm_list_init(&dm->cmd->pending_delete);
+		dm_pool_empty(dm->cmd->pending_delete_mem);
 	}
 
 	return 1;
@@ -3739,22 +3742,12 @@ out_no_root:
 int dev_manager_activate(struct dev_manager *dm, const struct logical_volume *lv,
 			 struct lv_activate_opts *laopts)
 {
-	dm_list_splice(&dm->pending_delete, &lv->vg->cmd->pending_delete);
-
 	if (!_tree_action(dm, lv, laopts, ACTIVATE))
 		return_0;
 
 	if (!_tree_action(dm, lv, laopts, CLEAN))
 		return_0;
 
-	if (!dm_list_empty(&dm->pending_delete)) {
-		log_debug("Preserving %d device(s) for removal while being suspended.",
-			  dm_list_size(&dm->pending_delete));
-		if (!(str_list_dup(lv->vg->cmd->mem, &lv->vg->cmd->pending_delete,
-				   &dm->pending_delete)))
-			return_0;
-	}
-
 	return 1;
 }
 

lib/commands/toolcontext.c

@@ -1492,6 +1492,8 @@ void destroy_config_context(struct cmd_context *cmd)
 		dm_pool_destroy(cmd->mem);
 	if (cmd->libmem)
 		dm_pool_destroy(cmd->libmem);
+	if (cmd->pending_delete_mem)
+		dm_pool_destroy(cmd->pending_delete_mem);
 
 	free(cmd);
 }
@@ -1520,6 +1522,9 @@ struct cmd_context *create_config_context(void)
 	if (!(cmd->mem = dm_pool_create("command", 4 * 1024)))
 		goto out;
 
+	if (!(cmd->pending_delete_mem = dm_pool_create("pending_delete", 1024)))
+		goto_out;
+
 	dm_list_init(&cmd->config_files);
 	dm_list_init(&cmd->tags);
 	dm_list_init(&cmd->hints);
@@ -1667,6 +1672,9 @@ struct cmd_context *create_toolcontext(unsigned is_clvmd,
 		goto out;
 	}
 
+	if (!(cmd->pending_delete_mem = dm_pool_create("pending_delete", 1024)))
+		goto_out;
+
 	if (!_init_lvm_conf(cmd))
 		goto_out;
 
@@ -1970,6 +1978,8 @@ void destroy_toolcontext(struct cmd_context *cmd)
 	if (cmd->libmem)
 		dm_pool_destroy(cmd->libmem);
 
+	if (cmd->pending_delete_mem)
+		dm_pool_destroy(cmd->pending_delete_mem);
 #ifndef VALGRIND_POOL
 	if (cmd->linebuffer) {
 		/* Reset stream buffering to defaults */

lib/commands/toolcontext.h

@@ -240,6 +240,7 @@ struct cmd_context {
 	const char *time_format;
 	unsigned rand_seed;
 	struct dm_list pending_delete;		/* list of LVs for removal */
+	struct dm_pool *pending_delete_mem;	/* memory pool for pending deletes */
 };
 
 /*