From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: [PATCH 06/14] libata: improve ATAPI draining Date: Fri, 30 Nov 2007 01:09:27 +0900 Message-ID: <474EE437.4040103@gmail.com> References: <1196346817387-git-send-email-htejun@gmail.com> <11963468192463-git-send-email-htejun@gmail.com> <20071129155956.4004ca89@the-village.bc.nu> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from rv-out-0910.google.com ([209.85.198.184]:25076 "EHLO rv-out-0910.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754218AbXK2QJj (ORCPT ); Thu, 29 Nov 2007 11:09:39 -0500 Received: by rv-out-0910.google.com with SMTP id k20so1589648rvb for ; Thu, 29 Nov 2007 08:09:38 -0800 (PST) In-Reply-To: <20071129155956.4004ca89@the-village.bc.nu> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Alan Cox Cc: jeff@garzik.org, linux-ide@vger.kernel.org, liml@rtr.ca, albertl@mail.com, jens.axboe@oracle.com, Albert Lee Alan Cox wrote: >> * Limit the amount of draining to ATAPI_MAX_DRAIN (16k currently). > > Why 16 not 64K ? > > Please add a comment to note that the drivers assume > - drain is only ever done on a stuck PIO xfer No. ATAPI draining is to accommodate buggy software and hardware and it's for all misc ATAPI commands whether PIO or DMA. > - drain occurs before any controller error/reset handling is done This is part of normal command processing, not really related to EH. Thanks. -- tejun