linux-ext4 - Re: Files full of zeros with coreutils-8.11 and xfs (FIEMAP related?)

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <4DAD987F.5000506@sandeen.net>
Date:	Tue, 19 Apr 2011 09:13:19 -0500
From:	Eric Sandeen <sandeen@...deen.net>
To:	Ted Ts'o <tytso@....edu>
CC:	Dave Chinner <david@...morbit.com>,
	Yongqiang Yang <xiaoqiangnk@...il.com>,
	Andreas Dilger <adilger@...ger.ca>, xfs-oss <xfs@....sgi.com>,
	"coreutils@....org" <coreutils@....org>,
	"linux-ext4@...r.kernel.org" <linux-ext4@...r.kernel.org>,
	Pádraig Brady <P@...igbrady.com>,
	Markus Trippelsdorf <markus@...ppelsdorf.de>
Subject: Re: Files full of zeros with coreutils-8.11 and xfs (FIEMAP related?)

On 4/19/11 9:09 AM, Ted Ts'o wrote:
> On Tue, Apr 19, 2011 at 05:45:38PM +1000, Dave Chinner wrote:
>> You are *not listening*. There is no #2. FIEMAP returns the extent
>> state _on disk_ at the time of the call.
> 
> Dave, you're being rather strident about your insistence about what
> FIEMAP's semantics are.  Part of the problem here is that it's *not*
> clear or settled.
> 
> If it really is the state _on_ _disk_, does XFS really have a DELALLOC
> bit _on_ _disk_?
> 
> 					- Ted
> 

no of course it doesn't....

But I too am confused about Dave's assertion that it only reflects ondisk state when we have that pesky delalloc flag.

Whose idea was that, anyway? ;)

I'd certainly buy the argument that it -should- only reflect ondisk state, and we should nuke the delalloc flag from orbit, if we could, though.

-Eric
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html