From mboxrd@z Thu Jan 1 00:00:00 1970 From: Boaz Harrosh Subject: Re: [PATCH 1/2] block: add support for discard limits Date: Mon, 02 Nov 2009 18:02:56 +0200 Message-ID: <4AEF02B0.2060506@panasas.com> References: <20091029150830.497006534@bombadil.infradead.org> <20091029151127.257902381@bombadil.infradead.org> <20091030050558.GC17714@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: Received: from qw-out-2122.google.com ([74.125.92.25]:1251 "EHLO qw-out-2122.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755364AbZKBQC6 (ORCPT ); Mon, 2 Nov 2009 11:02:58 -0500 Received: by qw-out-2122.google.com with SMTP id 9so1147385qwb.37 for ; Mon, 02 Nov 2009 08:03:03 -0800 (PST) In-Reply-To: Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: "Martin K. Petersen" Cc: Christoph Hellwig , linux-scsi@vger.kernel.org, axboe@kernel.dk, matthew@wil.cx On 11/02/2009 03:29 PM, Martin K. Petersen wrote: > > With heterogeneous md and dm devices there may not be a meaningful value > to put in the discard granularity field. Then what? > These alignment masks may only be base-2, no? If so then the max alignment of all devices will work for any device. I think Boaz