From owner-freebsd-hackers Sat Oct 19 0:54:32 2002 Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 8996D37B401; Sat, 19 Oct 2002 00:54:30 -0700 (PDT) Received: from critter.freebsd.dk (critter.freebsd.dk [212.242.86.163]) by mx1.FreeBSD.org (Postfix) with ESMTP id 582EB43EA3; Sat, 19 Oct 2002 00:54:29 -0700 (PDT) (envelope-from phk@critter.freebsd.dk) Received: from critter.freebsd.dk (localhost [127.0.0.1]) by critter.freebsd.dk (8.12.6/8.12.6) with ESMTP id g9J7sB01028473; Sat, 19 Oct 2002 09:54:13 +0200 (CEST) (envelope-from phk@critter.freebsd.dk) To: Maxim Sobolev Cc: hackers@FreeBSD.ORG, dillon@FreeBSD.ORG Subject: Re: Patch to allow a driver to report unrecoverable write errors to the buf layer In-Reply-To: Your message of "Fri, 18 Oct 2002 20:45:25 +0300." <3DB048B5.21097613@FreeBSD.org> Date: Sat, 19 Oct 2002 09:54:11 +0200 Message-ID: <28472.1035014051@critter.freebsd.dk> From: Poul-Henning Kamp Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG In message <3DB048B5.21097613@FreeBSD.org>, Maxim Sobolev writes: >Hi folks, > >I noticed that FreeBSD buf/bio subsystem has one very annoying problem >- once the write request is ejected into it, and write operation >failed, there seemingly no way valid to tell the layer to drop the >buffer. Instead, it retries the attempt over and over again, until >reboot, even though originator of request (usually vfs layer) was >already notified about failure and propagated error condition to the >underlying user-lever program. Yes, I noticed that appeared at some time. That misfeature should be removed in toto. If a retry can solve the issue, it's the drivers responsibility to retry as much as makes sense and then fail if it doesn't work. Neither the buf nor the bio layer should get involved in those retries. If you really want to change the behaviour here, you should add a flag on the buf going down, saying "Never, ever retry". -- 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. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message