From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753518AbbJGTBG (ORCPT ); Wed, 7 Oct 2015 15:01:06 -0400 Received: from mail-wi0-f170.google.com ([209.85.212.170]:36893 "EHLO mail-wi0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751716AbbJGTBD (ORCPT ); Wed, 7 Oct 2015 15:01:03 -0400 Subject: Re: [PATCH v5 1/4] uio: add ioctl support To: Stephen Hemminger References: <1444151859-10217-1-git-send-email-vladz@cloudius-systems.com> <1444151859-10217-2-git-send-email-vladz@cloudius-systems.com> <20151007084627.GA4270@kroah.com> <5614DDE5.1050100@cloudius-systems.com> <20151007172112.GC9702@kroah.com> <5615562A.1070105@cloudius-systems.com> Cc: Greg Kroah-Hartman , bruce.richardson@intel.com, linux-kernel@vger.kernel.org, hjk@hansjkoch.de, avi@cloudius-systems.com, corbet@lwn.net, alexander.duyck@gmail.com, gleb@cloudius-systems.com, mst@redhat.com From: Vlad Zolotarov Message-ID: <56156BEA.4050809@cloudius-systems.com> Date: Wed, 7 Oct 2015 22:00:58 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.1.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/07/15 21:05, Stephen Hemminger wrote: > > Thinking more of a custom filesystem like configfs > Why would configfs be better? I imagine the final files layout as follows: uioY device that would have enabled MSI-X would have a separate uio/uioY/msix/irqZ for each IRQ[Z] MSI-X vector. And this under the same roof with uio/uioY/maps/mapK files. We then need to implement the write() method for irqZ files so that it would accept the eventfd and bind it (or unbind if the value is negative). We may also make read() return not only the currently bond eventfd descriptor but also the corresponding MSI-X IRQ number.