From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753964Ab0F3InG (ORCPT ); Wed, 30 Jun 2010 04:43:06 -0400 Received: from verein.lst.de ([213.95.11.210]:39541 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753490Ab0F3InC (ORCPT ); Wed, 30 Jun 2010 04:43:02 -0400 Date: Wed, 30 Jun 2010 10:42:04 +0200 From: Christoph Hellwig To: Boaz Harrosh Cc: James Bottomley , Mike Snitzer , Christoph Hellwig , axboe@kernel.dk, dm-devel@redhat.com, linux-kernel@vger.kernel.org, martin.petersen@oracle.com, akpm@linux-foundation.org, linux-scsi@vger.kernel.org, FUJITA Tomonori Subject: Re: [PATCH 1/2] block: fix leaks associated with discard request payload Message-ID: <20100630084204.GA27609@lst.de> References: <20100622180029.GA15950@redhat.com> <1277582211-10725-1-git-send-email-snitzer@redhat.com> <1277652576.4366.19.camel@mulgrave.site> <4C2B012B.2000407@panasas.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4C2B012B.2000407@panasas.com> User-Agent: Mutt/1.3.28i X-Spam-Score: 0 () Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 30, 2010 at 11:32:43AM +0300, Boaz Harrosh wrote: > May I ask a silly question? Why the dynamic allocation? > > Why not have a const-static single global page at the block-layer somewhere > that will be used for all discard-type operations and be done with it once and > for all. A single page can be used for any size bio , any number of concurrent > discards, any ZERO needed operation. It can also be used by other operations > like padding and others. In fact isn't there one for the libsata padding? for UNMAP we need to write into the payload. And for ATA TRIM we need to write into the WRITE SAME payload. That's another layering violation for those looking for them, btw..