From d9dc6bef185bc2b0c0d642b2f1ae9cd1d9c72dd1 Mon Sep 17 00:00:00 2001
From: Mike Snitzer <snitzer@redhat.com>
Date: Wed, 18 Jan 2012 17:30:17 -0500
Subject: [PATCH 3/3] snapshot-merge support for invalid snapshot

Allow removal of an invalid snapshot that was to be merged on next activation.
Don't allow a user to merge an invalid snapshot.

---
 WHATS_NEW               |    2 ++
 lib/metadata/lv_manip.c |   20 ++++++++++++++++----
 tools/lvconvert.c       |    9 +++++++++
 3 files changed, 27 insertions(+), 4 deletions(-)

Index: lvm2/lib/metadata/lv_manip.c
===================================================================
--- lvm2.orig/lib/metadata/lv_manip.c
+++ lvm2/lib/metadata/lv_manip.c
@@ -3263,15 +3263,27 @@ int lv_remove_single(struct cmd_context 
 int lv_remove_with_dependencies(struct cmd_context *cmd, struct logical_volume *lv,
 				const force_t force, unsigned level)
 {
+	percent_t snap_percent;
 	struct dm_list *snh, *snht;
 	struct seg_list *sl, *tsl;
+	struct lvinfo info;
 
 	if (lv_is_cow(lv)) {
-		/* A merging snapshot cannot be removed directly */
+		/*
+		 * A merging snapshot cannot be removed directly unless
+		 * it has been invalidated.
+		 */
 		if (lv_is_merging_cow(lv) && !level) {
-			log_error("Can't remove merging snapshot logical volume \"%s\"",
-				  lv->name);
-			return 0;
+			if (lv_info(lv->vg->cmd, lv, 0, &info, 1, 0) &&
+			    info.exists && info.live_table) {
+				if (lv_snapshot_percent(lv, &snap_percent) &&
+				    ((snap_percent != PERCENT_INVALID) &&
+				     (snap_percent != PERCENT_MERGE_FAILED))) {
+					log_error("Can't remove merging snapshot logical volume \"%s\"",
+						  lv->name);
+					return 0;
+				}
+			}
 		}
 	}
 
Index: lvm2/tools/lvconvert.c
===================================================================
--- lvm2.orig/tools/lvconvert.c
+++ lvm2/tools/lvconvert.c
@@ -1709,6 +1709,8 @@ static int _lvconvert_single(struct cmd_
 {
 	struct lvconvert_params *lp = handle;
 	struct dm_list *failed_pvs;
+	struct lvinfo info;
+	percent_t snap_percent;
 
 	if (lv->status & LOCKED) {
 		log_error("Cannot convert locked LV %s", lv->name);
@@ -1742,6 +1744,13 @@ static int _lvconvert_single(struct cmd_
 				  lv->name);
 			return ECMD_FAILED;
 		}
+	        if (lv_info(lv->vg->cmd, lv, 0, &info, 1, 0)
+		    && info.exists && info.live_table &&
+		    (!lv_snapshot_percent(lv, &snap_percent) ||
+		     snap_percent == PERCENT_INVALID)) {
+			log_error("Unable to merge invalidated snapshot LV \"%s\"", lv->name);
+			return ECMD_FAILED;
+		}
 		if (!archive(lv->vg)) {
 			stack;
 			return ECMD_FAILED;
Index: lvm2/WHATS_NEW
===================================================================
--- lvm2.orig/WHATS_NEW
+++ lvm2/WHATS_NEW
@@ -1,5 +1,7 @@
 Version 2.02.89 - 
 ==================================
+  Allow removal of an invalid snapshot that was to be merged on next activation.
+  Don't allow a user to merge an invalid snapshot.
   Use m and M lv_attr to indicate that a snapshot merge failed in lvs.
   Differentiate between snapshot status of "Invalid" and "Merge failed".
   Lookup snapshot usage percent of origin volume when a snapshot is merging.