From owner-freebsd-current Mon Jan 6 21:07:51 1997 Return-Path: Received: (from root@localhost) by freefall.freebsd.org (8.8.4/8.8.4) id VAA28548 for current-outgoing; Mon, 6 Jan 1997 21:07:51 -0800 (PST) Received: from genesis.atrad.adelaide.edu.au (genesis.atrad.adelaide.edu.au [129.127.96.120]) by freefall.freebsd.org (8.8.4/8.8.4) with ESMTP id VAA28540 for ; Mon, 6 Jan 1997 21:07:46 -0800 (PST) Received: (from msmith@localhost) by genesis.atrad.adelaide.edu.au (8.8.2/8.7.3) id PAA08292; Tue, 7 Jan 1997 15:36:36 +1030 (CST) From: Michael Smith Message-Id: <199701070506.PAA08292@genesis.atrad.adelaide.edu.au> Subject: Re: kernel w/o source? [MOD_DECL in lkm.h] In-Reply-To: <199701070319.UAA13739@phaeton.artisoft.com> from Terry Lambert at "Jan 6, 97 08:19:14 pm" To: terry@lambert.org (Terry Lambert) Date: Tue, 7 Jan 1997 15:36:35 +1030 (CST) Cc: msmith@atrad.adelaide.edu.au, wpaul@skynet.ctr.columbia.edu, jb@cimlogic.com.au, current@freebsd.org X-Mailer: ELM [version 2.4ME+ PL28 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-current@freebsd.org X-Loop: FreeBSD.org Precedence: bulk Terry Lambert stands accused of saying: > > Yes, we could do a BIOS disk driver. I don't know whether it would > > actually require vm86 support (which is for running user processes, > > not kernel code), but it would be a shade hairy. Certainly it would > > be easiest to run it in a user process. > > It seems to me that we have working APM calls even without a real > VM86(). APM has a 32-bit callgate, and whilst designed for access by both 16 and 32-bit callers, often screws up with our current code. I haven't had time to play with my (failing) Sharp (Phoenix NoteBIOS 4) system, so I can't comment authoratatively on this. > It occurs to me that saving the first 640K and mapping it into the > address space of the putative caller using the same mechanism as APM > would likely work... No. A mechanism whereby a 16-bit environment could be created, and 16-bit code could be executed, would be required. I think it would be posible for this to run in vm86 mode, rather than real mode, for the purpose of accessing the disk BIOS. A mechanism for forwarding hardware interrupts to this environment would be necessary. > Terry Lambert -- ]] Mike Smith, Software Engineer msmith@gsoft.com.au [[ ]] Genesis Software genesis@gsoft.com.au [[ ]] High-speed data acquisition and (GSM mobile) 0411-222-496 [[ ]] realtime instrument control. (ph) +61-8-8267-3493 [[ ]] Unix hardware collector. "Where are your PEZ?" The Tick [[