From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261409AbVFJXKt (ORCPT ); Fri, 10 Jun 2005 19:10:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261389AbVFJXKj (ORCPT ); Fri, 10 Jun 2005 19:10:39 -0400 Received: from mustang.oldcity.dca.net ([216.158.38.3]:31403 "HELO mustang.oldcity.dca.net") by vger.kernel.org with SMTP id S261404AbVFJXHT (ORCPT ); Fri, 10 Jun 2005 19:07:19 -0400 Subject: Re: DMA mapping (was Re: [PATCH] cciss 2.6; replaces DMA masks with kernel defines) From: Lee Revell To: Matthew Wilcox Cc: Arjan van de Ven , Jeff Garzik , mike.miller@hp.com, akpm@osdl.org, axboe@suse.de, linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org In-Reply-To: <20050610213003.GI24611@parcelfarce.linux.theplanet.co.uk> References: <20050610143453.GA26476@beardog.cca.cpqcorp.net> <42A9C60E.3080604@pobox.com> <1118436000.6423.42.camel@mindpipe> <1118436306.5272.37.camel@laptopd505.fenrus.org> <1118438253.6423.72.camel@mindpipe> <20050610213003.GI24611@parcelfarce.linux.theplanet.co.uk> Content-Type: text/plain Date: Fri, 10 Jun 2005 19:08:11 -0400 Message-Id: <1118444891.6423.130.camel@mindpipe> Mime-Version: 1.0 X-Mailer: Evolution 2.3.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2005-06-10 at 22:30 +0100, Matthew Wilcox wrote: > On Fri, Jun 10, 2005 at 05:17:32PM -0400, Lee Revell wrote: > > OK, this covers the drivers I know. I didn't make any attempt to check > > them all. > > I know of two others ... > > sym2 has: > #define DMA_DAC_MASK 0x000000ffffffffffULL /* 40-bit */ > > and aic7xxx has: > const uint64_t mask_39bit = 0x7FFFFFFFFFULL; b44 needs 30 bit: #define B44_DMA_MASK 0x3fffffff These seem to be all over the place. I guess it saves a tiny bit of silicon. Don't these all violate the PCI spec? Should I just add everything from 24 to 63? Lee