From owner-svn-src-head@FreeBSD.ORG Tue Nov 16 10:55:12 2010 Return-Path: Delivered-To: svn-src-head@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 2EBA51065675; Tue, 16 Nov 2010 10:55:12 +0000 (UTC) (envelope-from ivoras@gmail.com) Received: from mail-qy0-f182.google.com (mail-qy0-f182.google.com [209.85.216.182]) by mx1.freebsd.org (Postfix) with ESMTP id 914538FC15; Tue, 16 Nov 2010 10:55:11 +0000 (UTC) Received: by qyk7 with SMTP id 7so568517qyk.13 for ; Tue, 16 Nov 2010 02:55:10 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:mime-version:sender:received :in-reply-to:references:from:date:x-google-sender-auth:message-id :subject:to:cc:content-type; bh=oIRuuwCzK986QI93anxIcXDqJ5NKYlR1nIRcg082M8g=; b=bZoWst8miB+/wk/6x8y86if+QtnHT4zhJD08f0ADgt204Bv8uPsdmFK6kLmJE7L13I QJZHB/rUo6RwUyZMn8GVB/EiWU1EmVUmOYbJA7IOOAe1qzgB/zt38XYdFV0/GtGLKx8B x6X9Gzn7VlvlebA6484F3dtTu8IM27cokmrj8= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:from:date :x-google-sender-auth:message-id:subject:to:cc:content-type; b=m5jW2DtR/UM7jjZOz5MgtmzlpZtu5pjMFD7cDkHs74AjXTqyXycAcAC2ABk4pqYN51 Tk9WnTynogrO6fCIjG9KIl73KYvxTZKAmejznD6ZMou1iiajnmzg+Oto0Io6USo0sLSX NOtfoG93jD1yZo3x4aMBapUbAjlt4PmscTnzA= Received: by 10.229.82.70 with SMTP id a6mr6280078qcl.9.1289904910837; Tue, 16 Nov 2010 02:55:10 -0800 (PST) MIME-Version: 1.0 Sender: ivoras@gmail.com Received: by 10.229.231.143 with HTTP; Tue, 16 Nov 2010 02:54:30 -0800 (PST) In-Reply-To: <20101116014817.GA25713@onelab2.iet.unipi.it> References: <201011121302.oACD2Qjt009385@svn.freebsd.org> <20101115171016.GB20524@onelab2.iet.unipi.it> <20101116014817.GA25713@onelab2.iet.unipi.it> From: Ivan Voras Date: Tue, 16 Nov 2010 11:54:30 +0100 X-Google-Sender-Auth: On0h3FL75zAc2UzvO5wnjJUGQ28 Message-ID: To: Luigi Rizzo Content-Type: text/plain; charset=UTF-8 Cc: svn-src-head@freebsd.org, Luigi Rizzo , src-committers@freebsd.org, svn-src-all@freebsd.org Subject: Re: svn commit: r215178 - in head: lib/libc/sys sys/kern sys/sys X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 16 Nov 2010 10:55:12 -0000 On 16 November 2010 02:48, Luigi Rizzo wrote: > On Tue, Nov 16, 2010 at 01:33:53AM +0100, Ivan Voras wrote: >> On 15 November 2010 18:10, Luigi Rizzo wrote: >> >> > 2. [generic] passing pointers between userland and kernel >> > requires remapping the pointer when going up or down. >> > As the mapping would be application specific, i don't >> > see much use in allowing room for a pointer without kernel code >> > to map userland <-> kernel pointers. >> >> I'm not thinking of passing a *working* pointer into the kernel but >> used as a cookie, similar to how it's used in kqueue: the intention >> being the application can send and get a pointer which means something >> to the application, not something usable to the kernel. > > oh, but then you are thinking of something completely different. > The SO_USER_COOKIE is never returned to the application; it is > only passed to another kernel subsystem, so it must be significant > there, not for the application. Ah, ok then. I was thinking you are maybe trying to do something else, like tagging a socket with additional information from userland.