862095 – liblvm2app: property "data_percent" returns -1 for thin volumes

RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.

Bug 862095 - liblvm2app: property "data_percent" returns -1 for thin volumes

Summary: liblvm2app: property "data_percent" returns -1 for thin volumes

Keywords:
Status:	CLOSED ERRATA
Alias:	None
Product:	Red Hat Enterprise Linux 6
Classification:	Red Hat
Component:	lvm2
Sub Component:
Version:	6.5
Hardware:	Unspecified
OS:	Unspecified
Priority:	medium
Severity:	unspecified
Target Milestone:	rc
Target Release:	---
Assignee:	Zdenek Kabelac
QA Contact:	Cluster QE
Docs Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+	depends on / blocked

Reported:	2012-10-01 20:42 UTC by benscott
Modified:	2013-02-21 08:14 UTC (History)
CC List:	13 users (show)
Fixed In Version:	lvm2-2.02.98-1.el6
Doc Type:	Bug Fix
Doc Text:	Unimplemented property "data_percent" for lvm2app caused return of incorrect value '-1' for thin volumes. It has been fixed by adding proper support for lvm_lv_get_property(lv, "data_percent");
Clone Of:
Environment:
Last Closed:	2013-02-21 08:14:08 UTC
Target Upstream Version:
Embargoed:

Attachments	(Terms of Use)
Patch to correctly return value of property "data_percent" (979 bytes, patch) 2012-10-03 16:49 UTC, Tony Asleson	no flags	Details \| Diff
View All

Links
System	ID	Private	Priority	Status	Summary	Last Updated
Red Hat Product Errata	RHBA-2013:0501	0	normal	SHIPPED_LIVE	lvm2 bug fix and enhancement update	2013-02-20 21:30:45 UTC

Description benscott 2012-10-01 20:42:30 UTC

Description of problem:

When using the following line of code:

   value = lvm_lv_get_property(lvmLV, "data_percent");

The value is the the same percentage reported by the "lvs" command for thin pools but returns invalid (-1) for thin volumes.

for example:

~# lvs
  LV        VG      Attr      LSize Pool     Data%  Move Log Copy%  Convert
  Pool_One  MyGroup twi-a-tz- 1.00g          9.96                        
  thin_vol2 MyGroup Vwi-a-tz- 2.00g Pool_One 4.98                        

for Pool_One  --> value = 9960937
for thin_vol2 --> value = -1


Version-Release number of selected component (if applicable):

  LVM version:     2.02.98(2)-git (2012-08-24)
  Library version: 1.02.77-git (2012-08-24)
  Driver version:  4.22.0

Additional info:

As reported in bug #838257 the number is reported with a uint64_t
but the percentage is an int32_t so sizes and signs are getting
mixed up.

Comment 2 Tony Asleson 2012-10-03 16:49:04 UTC

Created attachment 621019 [details]
Patch to correctly return value of property "data_percent"

Comment 3 Alasdair Kergon 2012-10-04 23:58:37 UTC

And what about the values when it's a snapshot, and various other conditions in the 'lvs' code.

Do we always want the output to match?  If so, we should find a better way to share the logic to arrive at the right number before going into the mechanics of outputting it either via liblvm or a cmdline report like lvs.

How many other fields similarly don't match?

Comment 4 Zdenek Kabelac 2012-10-05 08:41:14 UTC

Fixed upstream with slightly different patch to provide matching behavior with lvs reporting functionality (data_percent reports also snap_percent for old-snaps):

https://www.redhat.com/archives/lvm-devel/2012-October/msg00019.html

Comment 6 Zdenek Kabelac 2012-10-12 09:49:02 UTC

Here is simple    lvm2api test program which should pass now:

----
# Create pool & thin & snap LVs

lvcreate -L5M -T vg/pool
lvcreate -V1M -T vg/pool -n thin

----

#include "lvm2app.h"

int main(int argc, char *argv[])
{
	lvm_t handle;
	vg_t vg;
	lv_t lv;
	struct lvm_property_value v;

	handle = lvm_init(NULL);
	vg = lvm_vg_open(handle, argv[1], "r", 0);
	lv = lvm_lv_from_name(vg, "thin");
	v = lvm_lv_get_property(lv, "data_percent");

	lvm_vg_close(vg);
	lvm_quit(handle);

	return  (v.is_valid && v.value.integer != -1) ? 0 : 1;
}

Comment 9 errata-xmlrpc 2013-02-21 08:14:08 UTC

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

http://rhn.redhat.com/errata/RHBA-2013-0501.html

Note You need to log in before you can comment on or make changes to this bug.