From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 18 Apr 2002 01:57:22 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 18 Apr 2002 01:57:21 -0400 Received: from ns.virtualhost.dk ([195.184.98.160]:13068 "EHLO virtualhost.dk") by vger.kernel.org with ESMTP id ; Thu, 18 Apr 2002 01:57:21 -0400 Date: Thu, 18 Apr 2002 07:55:17 +0200 From: Jens Axboe To: peterc@gelato.unsw.edu.au Cc: linux-kernel@vger.kernel.org Subject: Re: A question about ll_10byte_cmd_build Message-ID: <20020418055517.GD858@suse.de> In-Reply-To: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Apr 18 2002, peterc@gelato.unsw.edu.au wrote: > > > (Linux 2.5.8) > In ll_rw_blk.c there's a function, ll_10byte_cmd_build() which is > supposed to be used to generate `10-byte commands'. > > It appears to generate a SCSI READ_10 or WRITE_10 command (which > happen to be identical in format to the ATAPI GPCMD_{READ,WRITE}_10 commands) > > Is this IDE specific, or is it meant to cover all block devices? > If it's IDE specific, why is it in ll_rw_blk.c, which is meant to be > common to all block devices? It's not IDE specific, since when does IDE use packet commands? It's not ATAPI specific either. > As far as I can tell, only ide-cd.c actually uses the function in a > stock 2.5.8 kernel --- so it could theoretically be moved to ide-cd.c. It's meant to be an example of a generic prep_rq_fn() queue function, a start the conversion of using struct request as the generic passer of cdb's. Only ide-cd uses it for now as you see, that's merely because lots of bits of the infrastructure are still missing. -- Jens Axboe