From owner-cvs-src@FreeBSD.ORG Mon Dec 17 15:02:47 2007 Return-Path: Delivered-To: cvs-src@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id C4AF516A421; Mon, 17 Dec 2007 15:02:47 +0000 (UTC) (envelope-from bms@incunabulum.net) Received: from out3.smtp.messagingengine.com (out3.smtp.messagingengine.com [66.111.4.27]) by mx1.freebsd.org (Postfix) with ESMTP id A1EC713C4E1; Mon, 17 Dec 2007 15:02:47 +0000 (UTC) (envelope-from bms@incunabulum.net) Received: from compute1.internal (compute1.internal [10.202.2.41]) by out1.messagingengine.com (Postfix) with ESMTP id 156007CA8B; Mon, 17 Dec 2007 09:43:57 -0500 (EST) Received: from heartbeat1.messagingengine.com ([10.202.2.160]) by compute1.internal (MEProxy); Mon, 17 Dec 2007 09:43:57 -0500 X-Sasl-enc: pYfoypjVnJfrNsuK8z7/bIcLsPw+XU5IjGMF5XmqlpWC 1197902636 Received: from [192.168.123.18] (82-35-112-254.cable.ubr07.dals.blueyonder.co.uk [82.35.112.254]) by mail.messagingengine.com (Postfix) with ESMTP id 1C14635C5; Mon, 17 Dec 2007 09:43:55 -0500 (EST) Message-ID: <47668B2B.5030206@incunabulum.net> Date: Mon, 17 Dec 2007 14:43:55 +0000 From: "Bruce M. Simpson" User-Agent: Thunderbird 1.5.0.13 (Windows/20070809) MIME-Version: 1.0 To: Poul-Henning Kamp References: <7131.1197840372@critter.freebsd.dk> In-Reply-To: <7131.1197840372@critter.freebsd.dk> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: cvs-src@FreeBSD.org, src-committers@FreeBSD.org, "Bruce M. Simpson" , cvs-all@FreeBSD.org Subject: Re: cvs commit: src/sbin/atacontrol atacontrol.c X-BeenThere: cvs-src@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: CVS commit messages for the src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 17 Dec 2007 15:02:47 -0000 Poul-Henning Kamp wrote: > I have the attached patch in sos@ mailbox for approval, that adds > BIO_DELETE support for the ata driver. > > I also want to implement a -E option to fsck(8) to erase all > unallocated blocks. > > And finally the big item: msdosfs and ufs support to issue BIO_DELETE > when files are deleted. UFS is nasty because of soft-updates. > Aha, I understand now. CFA and SATA vendors have gone off in two separate directions: * PATA and SATA drives, for a few years now, have tended to rewrite one cylinder at a time, which implies erasing the data on that cylinder. * NAND Flash devices should not have their sectors erased unless absolutely necessary, to implement wear levelling. So it's necessary to tell the block layer, explicitly, beneath UFS, about the intention to delete the data contained within such blocks. Thanks for doing this. BMS