From: Jonathan Earl Brassow <jbrassow@redhat.com>
Date: Thu, 26 Aug 2010 16:29:12 +0000 (+0000)
Subject: This patch fixes a problem where the mirror polling process
X-Git-Tag: v2_02_74~15
X-Git-Url: https://sourceware.org/git/?a=commitdiff_plain;h=fe8b1db933d598e3acbd731b5133666c172168a3;p=lvm2.git

This patch fixes a problem where the mirror polling process
may never complete.

If you convert from a linear to a mirror and then convert that
mirror back to linear /while/ the previous (up)convert is
taking place, the mirror polling process will never complete.
This is because the function that polls the mirror for
completion doesn't check if it is still polling a mirror and
the copy_percent that it gets back from the linear device is
certainly never 100%.

The fix is simply to check if the daemon is still looking at
a mirror device - if not, return PROGRESS_CHECK_FAILED.

The user sees the following output from the first (up)convert
if someone else sneaks in and does a down-convert shortly
after their convert:
[root@bp-01 ~]# lvconvert -m1 vg/lv
  vg/lv: Converted: 43.4%
  ABORTING: Mirror percentage check failed.
---

diff --git a/WHATS_NEW b/WHATS_NEW
index 36d166c05..21559d5f1 100644
--- a/WHATS_NEW
+++ b/WHATS_NEW
@@ -1,5 +1,6 @@
 Version 2.02.74 - 
 ==================================
+  Make poll_mirror_progress report PROGRESS_CHECK_FAILED if LV is not a mirror.
   Like mirrors, don't scan origins if ignore_suspended_devices() is set.
   Fix return type qualifier to avoid compiler warning. (2.02.69)
   Automatically generate LSB Requires-Start for clvmd init script.
diff --git a/tools/polldaemon.c b/tools/polldaemon.c
index 2d5a8cdfd..41a5cd67f 100644
--- a/tools/polldaemon.c
+++ b/tools/polldaemon.c
@@ -78,7 +78,8 @@ progress_t poll_mirror_progress(struct cmd_context *cmd,
 	percent_range_t percent_range, overall_percent_range;
 	uint32_t event_nr = 0;
 
-	if (!lv_mirror_percent(cmd, lv, !parms->interval, &segment_percent,
+	if (!lv_is_mirrored(lv) ||
+	    !lv_mirror_percent(cmd, lv, !parms->interval, &segment_percent,
 			       &percent_range, &event_nr) ||
 	    (percent_range == PERCENT_INVALID)) {
 		log_error("ABORTING: Mirror percentage check failed.");