From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([208.118.235.92]:38043)
	by lists.gnu.org with esmtp (Exim 4.71) (envelope-from <hch@lst.de>)
	id 1SBT6l-0004QN-3i
	for qemu-devel@nongnu.org; Sat, 24 Mar 2012 11:42:24 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <hch@lst.de>) id 1SBT6j-0000HR-F0
	for qemu-devel@nongnu.org; Sat, 24 Mar 2012 11:42:22 -0400
Received: from verein.lst.de ([213.95.11.211]:52385 helo=newverein.lst.de)
	by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from <hch@lst.de>)
	id 1SBT6j-0000HB-99
	for qemu-devel@nongnu.org; Sat, 24 Mar 2012 11:42:21 -0400
Date: Sat, 24 Mar 2012 16:42:19 +0100
From: Christoph Hellwig <hch@lst.de>
Message-ID: <20120324154219.GG13014@lst.de>
References: <1331226917-6658-1-git-send-email-pbonzini@redhat.com>
	<1331226917-6658-18-git-send-email-pbonzini@redhat.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <1331226917-6658-18-git-send-email-pbonzini@redhat.com>
Subject: Re: [Qemu-devel] [RFC PATCH 17/17] raw: implement is_allocated
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Paolo Bonzini <pbonzini@redhat.com>
Cc: qemu-devel@nongnu.org

On Thu, Mar 08, 2012 at 06:15:17PM +0100, Paolo Bonzini wrote:
> SEEK_DATA and SEEK_HOLE can be used to implement the is_allocated
> callback for raw files.  These currently work on btrfs, with an XFS
> implementation also coming soon.

Btw - if you're interested in a bit more kernel hacking it would be cool
to implement it for block devices using GET LBA STATUS.