From mboxrd@z Thu Jan 1 00:00:00 1970 From: Martin Murray Subject: Re: [UPDATED][PATCH 2.6.14]: ide: Enable larger taskfile transfers Date: Thu, 3 Nov 2005 16:43:55 -0500 Message-ID: <20051103214355.GA3516@deepthought.org> References: <20051102084917.GM26049@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from carbon.deepthought.org ([66.180.175.50]:53407 "EHLO carbon.deepthought.org") by vger.kernel.org with ESMTP id S1030504AbVKCVoB (ORCPT ); Thu, 3 Nov 2005 16:44:01 -0500 Content-Disposition: inline In-Reply-To: <20051102084917.GM26049@suse.de> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: linux-ide@vger.kernel.org Just a few quick questions: regarding HDIO_DRIVE_TASKFILE: I don't see any exact information, however, from what I can infer from the code, it appears that while the user can specify an input buffer and/or an output buffer, only one of the buffers would be filled with useful information. Is it reasonable to assume that req_task->out_size == 0 req_task->in_size == 0? Or, more specifically, is it reasonable to return -EINVAL if both are non zero? If I were to do zero_copy IO using blk_rq_map_user, should I verify the user buffer is valid with access_ok() ? Why does ide_diag_taskfile() allocate a custom request structure instead of using blk_get_request(drive->queue, ...) ? Given HDIO_DRIVE_TASKFILE, what is the purpose of HDIO_DRIVE_TASK and HDIO_DRIVE_CMD? Thank you, Martin