From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gleb Natapov Subject: Re: [PATCHv4 15/15] Pass boot device list to firmware. Date: Mon, 15 Nov 2010 09:40:08 +0200 Message-ID: <20101115074008.GF7948@redhat.com> References: <1289749181-12070-1-git-send-email-gleb@redhat.com> <1289749181-12070-16-git-send-email-gleb@redhat.com> <20101115034033.GA1309@morn.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: qemu-devel@nongnu.org, kvm@vger.kernel.org, blauwirbel@gmail.com, armbru@redhat.com, alex.williamson@redhat.com, mst@redhat.com To: "Kevin O'Connor" Return-path: Received: from mx1.redhat.com ([209.132.183.28]:41106 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757505Ab0KOHkM (ORCPT ); Mon, 15 Nov 2010 02:40:12 -0500 Content-Disposition: inline In-Reply-To: <20101115034033.GA1309@morn.localdomain> Sender: kvm-owner@vger.kernel.org List-ID: On Sun, Nov 14, 2010 at 10:40:33PM -0500, Kevin O'Connor wrote: > On Sun, Nov 14, 2010 at 05:39:41PM +0200, Gleb Natapov wrote: > > +/* > > + * This function returns device list as an array in a below format: > > + * +-----+-----+---------------+-----+---------------+-- > > + * | n | l1 | devpath1 | l2 | devpath2 | ... > > + * +-----+-----+---------------+-----+---------------+-- > > + * where: > > + * n - a number of devise pathes (one byte) > > + * l - length of following device path string (one byte) > > + * devpath - non-null terminated string of length l representing > > + * one device path > > + */ > > Why not just return a newline separated list that is null terminated? > Doing it like this will needlessly complicate firmware side. How do you know how much memory to allocate before reading device list? Doing it like Blue suggest (have BOOTINDEX_LEN and BOOTINDEX_STRING) solves this. To create nice array from bootindex string you firmware will still have to do additional pass on it though. With format like above the code would look like that: qemu_cfg_read(&n, 1); arr = alloc(n); for (i=0; i