From 8de912b677a24ba6a517832be03916835f8ccd15 Mon Sep 17 00:00:00 2001
From: Zdenek Kabelac <zkabelac@redhat.com>
Date: Wed, 19 Oct 2011 16:39:09 +0000
Subject: [PATCH] Simple validation of messages in mda

Check we do not combine multiple messages for same LV target
and switch to use  'delete_id' to make it clear for what this device_id
is being used.
---
 lib/metadata/metadata.h   |  2 +-
 lib/metadata/thin_manip.c | 29 +++++++++++++++++++++++++++--
 2 files changed, 28 insertions(+), 3 deletions(-)

diff --git a/lib/metadata/metadata.h b/lib/metadata/metadata.h
index b71be4cee..11cac5701 100644
--- a/lib/metadata/metadata.h
+++ b/lib/metadata/metadata.h
@@ -455,7 +455,7 @@ int attach_pool_data_lv(struct lv_segment *seg,
 int attach_pool_lv(struct lv_segment *seg, struct logical_volume *pool_lv);
 int detach_pool_lv(struct lv_segment *seg);
 int attach_pool_message(struct lv_segment *seg, dm_thin_message_t type,
-			struct logical_volume *lv, uint32_t device_id,
+			struct logical_volume *lv, uint32_t delete_id,
 			int read_only);
 int detach_pool_messages(struct lv_segment *seg);
 
diff --git a/lib/metadata/thin_manip.c b/lib/metadata/thin_manip.c
index ef16d270c..afa762806 100644
--- a/lib/metadata/thin_manip.c
+++ b/lib/metadata/thin_manip.c
@@ -81,11 +81,36 @@ int detach_pool_lv(struct lv_segment *seg)
 }
 
 int attach_pool_message(struct lv_segment *seg, dm_thin_message_t type,
-			struct logical_volume *lv, uint32_t device_id,
+			struct logical_volume *lv, uint32_t delete_id,
 			int read_only)
 {
 	struct lv_thin_message *tmsg;
 
+	dm_list_iterate_items(tmsg, &seg->thin_messages) {
+		if (tmsg->type == type) {
+			switch (tmsg->type) {
+			case DM_THIN_MESSAGE_CREATE_SNAP:
+			case DM_THIN_MESSAGE_CREATE_THIN:
+			case DM_THIN_MESSAGE_TRIM:
+				if (tmsg->u.lv == lv) {
+					log_error("Message referring LV %s already queued for %s.",
+						  tmsg->u.lv->name, seg->lv->name);
+					return 0;
+				}
+				break;
+			case DM_THIN_MESSAGE_DELETE:
+				if (tmsg->u.delete_id == delete_id) {
+					log_error("Delete of device %u already queued for %s.",
+						  tmsg->u.delete_id, seg->lv->name);
+					return 0;
+				}
+				break;
+			default:
+				break;
+			}
+		}
+	}
+
 	if (!(tmsg = dm_pool_alloc(seg->lv->vg->vgmem, sizeof(*tmsg)))) {
 		log_error("Failed to allocate memory for message.");
 		return 0;
@@ -98,7 +123,7 @@ int attach_pool_message(struct lv_segment *seg, dm_thin_message_t type,
 		tmsg->u.lv = lv;
 		break;
 	case DM_THIN_MESSAGE_DELETE:
-		tmsg->u.delete_id = device_id;
+		tmsg->u.delete_id = delete_id;
 		break;
 	default:
 		log_error(INTERNAL_ERROR "Unsupported message type %d", type);