From da5284a500338b458ade34c1a88d461acde52b71 Mon Sep 17 00:00:00 2001
From: Zdenek Kabelac <zkabelac@redhat.com>
Date: Wed, 24 Jul 2013 15:25:22 +0200
Subject: [PATCH] thin: lvconvert cannot convert pool to mirror

Suggest to use _tdata and _tmeta devices for that.
This fixes regression from too relaxed change in
f1d5f6ae81f4723e6aeb2f04bd68cba59cd65403

Without this patch there are some empty LVs created before
mirror code recognizes it cannot continue.

(in release fix)
---
 test/shell/lvconvert-thin.sh |  3 +++
 tools/lvconvert.c            | 27 +++++++++++++++++++++++++++
 2 files changed, 30 insertions(+)

diff --git a/test/shell/lvconvert-thin.sh b/test/shell/lvconvert-thin.sh
index a84c1d162..3cbfd2cf4 100644
--- a/test/shell/lvconvert-thin.sh
+++ b/test/shell/lvconvert-thin.sh
@@ -95,4 +95,7 @@ grep "WARNING: Chunk size is too small" err
 
 #lvs -a -o+chunk_size,stripe_size,seg_pe_ranges
 
+# Convertions of pool to mirror is unsupported
+not lvconvert -m1 $vg/$lv1
+
 vgremove -ff $vg
diff --git a/tools/lvconvert.c b/tools/lvconvert.c
index 62334d858..bd0749706 100644
--- a/tools/lvconvert.c
+++ b/tools/lvconvert.c
@@ -1553,6 +1553,27 @@ static int _lvconvert_mirrors_repair(struct cmd_context *cmd,
 	return 1;
 }
 
+static int _lvconvert_validate_thin(struct logical_volume *lv,
+				    struct lvconvert_params *lp)
+{
+	if (!lv_is_thin_pool(lv) && !lv_is_thin_volume(lv))
+		return 1;
+
+	log_error("Converting thin%s segment type for \"%s/%s\" to %s is not supported.",
+		  lv_is_thin_pool(lv) ? " pool" : "",
+		  lv->vg->name, lv->name, lp->segtype->name);
+
+	if (lv_is_thin_volume(lv))
+		return 0;
+
+	/* Give advice for thin pool conversion */
+	log_error("For pool data volume conversion use \"%s/%s\".",
+		  lv->vg->name, seg_lv(first_seg(lv), 0)->name);
+	log_error("For pool metadata volume conversion use \"%s/%s\".",
+		  lv->vg->name, first_seg(lv)->metadata_lv->name);
+	return 0;
+}
+
 /*
  * _lvconvert_mirrors
  *
@@ -1575,6 +1596,9 @@ static int _lvconvert_mirrors(struct cmd_context *cmd,
 		return 0;
 	}
 
+	if (!_lvconvert_validate_thin(lv, lp))
+		return_0;
+
 	/* Adjust mimage and/or log count */
 	if (!_lvconvert_mirrors_parse_params(cmd, lv, lp,
 					     &old_mimage_count, &old_log_count,
@@ -1676,6 +1700,9 @@ static int lvconvert_raid(struct logical_volume *lv, struct lvconvert_params *lp
 		return 0;
 	}
 
+	if (!_lvconvert_validate_thin(lv, lp))
+		return_0;
+
 	if (!is_valid_raid_conversion(seg->segtype, lp->segtype)) {
 		log_error("Unable to convert %s/%s from %s to %s",
 			  lv->vg->name, lv->name,