From: Chris Murphy <lists@colorremedies.com>
To: Adam Borowski <kilobyte@angband.pl>
Cc: Amin Hassani <ahassani@chromium.org>,
Btrfs BTRFS <linux-btrfs@vger.kernel.org>
Subject: Re: Btrfs disk layout question
Date: Tue, 11 Apr 2017 22:18:33 -0600 [thread overview]
Message-ID: <CAJCQCtTyNUx-P2aPNBE0x2W01qUfrBcHyA-46frM4X+suKMxrw@mail.gmail.com> (raw)
In-Reply-To: <20170411210023.vfqck3h6nepdow3z@angband.pl>
On Tue, Apr 11, 2017 at 3:00 PM, Adam Borowski <kilobyte@angband.pl> wrote:
> On Tue, Apr 11, 2017 at 12:15:32PM -0700, Amin Hassani wrote:
>> I am working on a project with Btrfs and I was wondering if there is
>> any way to see the disk layout of the btrfs image. Let's assume I have
>> a read-only btrfs image with compression on and only using one disk
>> (no raid or anything). Is it possible to get a set of offset-lengths
>> for each file
>
> While btrfs-specific ioctls give more information, you might want to look at
> FIEMAP (Documentation/filesystems/fiemap.txt) as it works on most
> filesystems, not just btrfs. One interface to FIEMAP is provided in
> "/usr/sbin/filefrag -v".
Good idea. Although, on Btrfs I'm pretty sure it reports the Btrfs
(internal) logical addressing; not the actual physical sector address
on the drive. So it depends on what the original poster is trying to
discover.
--
Chris Murphy
next prev parent reply other threads:[~2017-04-12 4:18 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-04-11 19:15 Btrfs disk layout question Amin Hassani
2017-04-11 20:43 ` Chris Murphy
2017-04-11 21:00 ` Adam Borowski
2017-04-12 4:18 ` Chris Murphy [this message]
2017-04-12 11:20 ` Austin S. Hemmelgarn
2017-04-12 16:44 ` Andrei Borzenkov
2017-04-12 16:50 ` Amin Hassani
2017-04-12 16:56 ` Austin S. Hemmelgarn
2017-04-12 17:21 ` Chris Murphy
2017-04-13 3:26 ` Andrei Borzenkov
2017-04-15 6:14 ` Andrei Borzenkov
2017-04-15 17:06 ` Chris Murphy
2017-04-12 17:25 ` Hans van Kranenburg
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