Bug 653234

Summary: filefrag returns wrong extent counts
Product: Red Hat Enterprise Linux 6 Reporter: Igor Zhang <yugzhang>
Component: e2fsprogsAssignee: Eric Sandeen <esandeen>
Status: CLOSED ERRATA QA Contact: BaseOS QE - Apps <qe-baseos-apps>
Severity: low Docs Contact:
Priority: low    
Version: 6.0CC: bnater, branto, esandeen, sct
Target Milestone: rc   
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: e2fsprogs-1.41.12-5.el6 Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2011-05-19 14:07:20 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description Igor Zhang 2010-11-15 03:36:18 UTC 
Description of problem:
When testing xfs with xfstests, 218 always failed and then I found a problem about filefrag.
Steps(on top of ext4):
# touch a
# filefrag a
a: 0 extents found
  ^^^^ 
# filefrag -v a
Filesystem type is: ef53
File size of a is 0 (0 blocks, blocksize 4096)
 ext logical physical expected length flags
a: 1 extent found
  ^^^^
[root@tyrannosaurus ~]# rpm -qf `which filefrag`
e2fsprogs-1.41.12-3.el6.x86_64

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


How reproducible:


Steps to Reproduce:
1.
2.
3.
  
Actual results:
filefrag returns wrong extent counts

Expected results:
With or without the option -v, filefrag should return a consistent extent count

Additional info:
RHEL5.6 preserved this behaviour:
[root@intel-s3e3144-02 ~]# touch a
[root@intel-s3e3144-02 ~]# filefrag a
a: 1 extent found
  ^^^^
[root@intel-s3e3144-02 ~]# filefrag -v a
Checking a
Filesystem type is: ef53
Filesystem cylinder groups is approximately 435
Blocksize of file a is 4096
File size of a is 0 (0 blocks)
First block: 0
Last block: 0
a: 1 extent found
  ^^^^
[root@intel-s3e3144-02 ~]# rpm -qf `which filefrag`
e2fsprogs-1.39-23.el5
Comment 2 Eric Sandeen 2010-11-15 03:57:01 UTC 
Yes, filefrag is kind of a mess in this respect.
Comment 3 Eric Sandeen 2010-11-22 15:33:06 UTC 
There are some oddities in how filefrag reports extents - depending on how it's invoked and what type of file it's looking at, it (intentionally, I think) reports different numbers of extents.  But this looks like an actual bug; I'll fix things that look like bugs and explain away things that are part of the upstream design ;)
Comment 4 Eric Sandeen 2010-11-23 23:30:12 UTC 
Sent a patch for this upstream.

http://marc.info/?l=linux-ext4&m=129055450828278&w=2

-Eric
Comment 5 Eric Sandeen 2010-12-16 20:09:35 UTC 
Built & tagged in e2fsprogs-1.41.12-5.el6
Comment 7 Branislav Náter 2011-03-04 12:50:22 UTC 
Bugfix was successfully verified on package e2fsprogs-1.41.12-7.el6 on all architectures (i386,x86_64,ppc64,s390x).

filefrag is now displaying correct values of extents.

# touch b
# filefrag b
b: 0 extents found
# filefrag -v b
Filesystem type is: ef53
File size of b is 0 (0 blocks, blocksize 4096)
b: 0 extents found
Comment 8 errata-xmlrpc 2011-05-19 14:07:20 UTC 
An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on therefore solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.

http://rhn.redhat.com/errata/RHBA-2011-0702.html