From owner-freebsd-current@FreeBSD.ORG Fri Apr 23 10:13:45 2010 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 57A1D106566B; Fri, 23 Apr 2010 10:13:45 +0000 (UTC) (envelope-from mavbsd@gmail.com) Received: from ey-out-2122.google.com (ey-out-2122.google.com [74.125.78.26]) by mx1.freebsd.org (Postfix) with ESMTP id AF47F8FC16; Fri, 23 Apr 2010 10:13:44 +0000 (UTC) Received: by ey-out-2122.google.com with SMTP id d26so671006eyd.9 for ; Fri, 23 Apr 2010 03:13:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:sender:message-id:date:from :user-agent:mime-version:to:cc:subject:references:in-reply-to :x-enigmail-version:content-type:content-transfer-encoding; bh=Y08EZZxwuqtTgIsS9PuPizOfC8qOVJPtsI2f4rEQ9sI=; b=BuyOsycAOnfavFDFix1UkiAG754GP3khgwJ/qLngt1NbCpjBlT/VeMrMgepmGwvfWR zHYmrrJyQxxa/UvShfvKG6KWfTZqIliZUDi2nufJzl3Gd7tVSoCFgKO0HxRX6GqYom3b WgSpAFDrpBNhMAKfpE4DBBMpauvFT3bl5t2GM= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:x-enigmail-version:content-type :content-transfer-encoding; b=KAL9htV1QVxTHHERovu/BWqzpMmF8fpglxDvVZnqJ1xVjjjHRXspKsBoRkAlFukvbc Xfi/vA9NYJSsBdqAgEgUXbYEC6R8EX8fOJuAKtvya4apdFZ0PVSzoSVLeihN6f4IKihN BTg5a5KFxLH9Q6V75mmeoYmYqI1dif8fjDnqs= Received: by 10.102.254.24 with SMTP id b24mr6392099mui.5.1272017623371; Fri, 23 Apr 2010 03:13:43 -0700 (PDT) Received: from mavbook.mavhome.dp.ua (pc.mavhome.dp.ua [212.86.226.226]) by mx.google.com with ESMTPS id y37sm3735511mug.52.2010.04.23.03.13.42 (version=SSLv3 cipher=RC4-MD5); Fri, 23 Apr 2010 03:13:42 -0700 (PDT) Sender: Alexander Motin Message-ID: <4BD172CA.4040106@FreeBSD.org> Date: Fri, 23 Apr 2010 13:13:30 +0300 From: Alexander Motin User-Agent: Thunderbird 2.0.0.24 (X11/20100402) MIME-Version: 1.0 To: Paul Wootton References: <4BD06BD9.6030401@FreeBSD.org> <4BD15D23.8090501@fletchermoorland.co.uk> In-Reply-To: <4BD15D23.8090501@fletchermoorland.co.uk> X-Enigmail-Version: 0.96.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: FreeBSD-Current , freebsd-geom@freebsd.org Subject: Re: Switchover to CAM ATA? X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 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: Fri, 23 Apr 2010 10:13:45 -0000 Paul Wootton wrote: > Alexander Motin wrote: >> Can we do switchover now, or some more reasons preventing this? > > The only thing I miss about the old ATA layer was that I knew that a > drive on a particular controller would always be assigned the same adX > number, whether is was present at boot time, or added days later. This > could get a little messy having ad2, ad4, ad12, ad20 and ad22, but at > least if I added a new drive, it would always attach to say ad8. > > Can this be done on the new CAM ATA? Binding to controller ports and device IDs can be managed for any CAM device via device.hints as described in cam(4). This scheme is a slightly more complicated (you have to explicitly define wanted mapping), but more flexible. Previous one just inapplicable now. Modern controllers (especially with Port Multipliers) could support different (often big) number of devices per channel, making device list with static numbering too sparse. -- Alexander Motin