From owner-freebsd-current@FreeBSD.ORG Mon Mar 28 16:39:24 2005 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 1CA1716A4CE for ; Mon, 28 Mar 2005 16:39:24 +0000 (GMT) Received: from critter.freebsd.dk (f170.freebsd.dk [212.242.86.170]) by mx1.FreeBSD.org (Postfix) with ESMTP id 457A343D48 for ; Mon, 28 Mar 2005 16:39:23 +0000 (GMT) (envelope-from phk@critter.freebsd.dk) Received: from critter.freebsd.dk (localhost [127.0.0.1]) by critter.freebsd.dk (8.13.3/8.13.1) with ESMTP id j2SGdM5Y034379; Mon, 28 Mar 2005 18:39:22 +0200 (CEST) (envelope-from phk@critter.freebsd.dk) To: Scott Long From: "Poul-Henning Kamp" In-Reply-To: Your message of "Mon, 28 Mar 2005 09:28:28 PDT." <424830AC.7090309@samsco.org> Date: Mon, 28 Mar 2005 18:39:22 +0200 Message-ID: <34378.1112027962@critter.freebsd.dk> Sender: phk@critter.freebsd.dk cc: "current@freebsd.org" cc: vova@fbsd.ru cc: "Matthew N. Dodd" cc: freebsd-mobile@freebsd.org cc: Julian Elischer cc: ticso@cicely.de Subject: Re: Reattach/redetect allways connected umass device - is it possible ? X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 28 Mar 2005 16:39:24 -0000 In message <424830AC.7090309@samsco.org>, Scott Long writes: >>>So are you saying that an async notification mechanism needs to be >>>invented for SCSI, or that all SCSI users should be required to use >>>SES or SAFTE enclosures for all SCSI devices, or that we should be like >>>Windows and constantly poll the devices? >> >> I don't care _how_ we make CAM/SCSI behave like the users expect. > >Well, I waved my hands at it for a few minutes, but nothing changed... >hmm.... =-) > >My question to you was partially rhetorical, That's why you got a terse answer indicating that the problem may be a disparity between SCSI and users (reasonable IMO) expectations to how devices act. I'm not claiming there is any perfect solution, but that doesn't mean that we shouldn't attempt to create a decent or at least workable solution. CD drives are a very specific problem because the ioctls we implement (and want to keep implementing for compatibility reasons) are defined without regard to the drive vs. media dictomy. atapi-cd implments what looks to be a workable workaround for this. I can't possibly why disk devices can't just simulate DTRT with polling. I even remember trying to implement that in scsi_da and I probably still have the hole in my mailbox where a response from the CAM/SCSI clued would have gone, had something like that existed. I think I ran into this issue well over two years ago, and all my attempts to get people to look at it failed and I simply parked it "until somebody gives a shit". Now that somebody does, can we stop religious slamming ancient and bogus user interaction models around and work together to find out how to implement or at least simulate something that makes sense in this day and time ? -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk@FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence.