From owner-freebsd-hackers@FreeBSD.ORG Mon May 7 17:46:12 2012 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 2A83D1065670; Mon, 7 May 2012 17:46:12 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from bigwig.baldwin.cx (bigknife-pt.tunnel.tserv9.chi1.ipv6.he.net [IPv6:2001:470:1f10:75::2]) by mx1.freebsd.org (Postfix) with ESMTP id F217C8FC14; Mon, 7 May 2012 17:46:11 +0000 (UTC) Received: from jhbbsd.localnet (unknown [209.249.190.124]) by bigwig.baldwin.cx (Postfix) with ESMTPSA id 6F03EB95D; Mon, 7 May 2012 13:46:11 -0400 (EDT) From: John Baldwin To: Andriy Gapon Date: Mon, 7 May 2012 13:38:12 -0400 User-Agent: KMail/1.13.5 (FreeBSD/8.2-CBSD-20110714-p13; KDE/4.5.5; amd64; ; ) References: <4F8999D2.1080902@FreeBSD.org> <4FA7E069.8020208@FreeBSD.org> <4FA7E729.4000308@FreeBSD.org> In-Reply-To: <4FA7E729.4000308@FreeBSD.org> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201205071338.12807.jhb@freebsd.org> X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.2.7 (bigwig.baldwin.cx); Mon, 07 May 2012 13:46:11 -0400 (EDT) Cc: freebsd-fs@freebsd.org, freebsd-hackers@freebsd.org, Bruce Evans Subject: Re: [review request] zfsboot/zfsloader: support accessing filesystems within a pool X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 07 May 2012 17:46:12 -0000 On Monday, May 07, 2012 11:15:53 am Andriy Gapon wrote: > on 07/05/2012 17:47 Andriy Gapon said the following: > > on 07/05/2012 16:53 John Baldwin said the following: > >> Ok. Maybe add one comment to the bootargs.h head to explain that the 'bootargs' > >> struct starts at ARGOFF and can grow up, while struct bootinfo is copied such that > >> it's end is at the top of the argument area and grows down. > > > > Will do. > > Could you please check the wording and correct it or suggest alternatives? > Thank you. > > diff --git a/sys/boot/i386/common/bootargs.h b/sys/boot/i386/common/bootargs.h > index 510efdd..8bc1b32 100644 > --- a/sys/boot/i386/common/bootargs.h > +++ b/sys/boot/i386/common/bootargs.h > @@ -29,6 +29,15 @@ > #define BF_OFF 8 /* offsetof(struct bootargs, bootflags) */ > #define BI_OFF 20 /* offsetof(struct bootargs, bootinfo) */ > > +/* > + * We reserve some space above BTX allocated stack for the arguments > + * and certain data that could hang off them. Currently only struct bootinfo > + * is supported in that category. The bootinfo is placed at the top > + * of the arguments area and the actual arguments are placed at ARGOFF offset > + * from the top and grow towards the top. Hopefully we have enough space > + * for bootinfo and the arguments to not run into each other. > + * Arguments area below ARGOFF is reserved for future use. > + */ > #define ARGSPACE 0x1000 /* total size of the BTX args area */ > #define ARGOFF 0x800 /* actual args offset within the args area */ > #define ARGADJ (ARGSPACE - ARGOFF) I think this is good, thanks! -- John Baldwin