From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754591Ab1AJRTx (ORCPT ); Mon, 10 Jan 2011 12:19:53 -0500 Received: from mx1.redhat.com ([209.132.183.28]:46918 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754392Ab1AJRTv (ORCPT ); Mon, 10 Jan 2011 12:19:51 -0500 Date: Mon, 10 Jan 2011 19:19:04 +0200 From: "Michael S. Tsirkin" To: Gleb Natapov Cc: Milton Miller , Rusty Russell , Anthony Liguori , Jamie Lokier , Thomas Weber , virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] virtio: remove virtio-pci root device Message-ID: <20110110171904.GA30058@redhat.com> References: <20110105191711.GA27489@redhat.com> <20110110171046.GB27292@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110110171046.GB27292@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jan 10, 2011 at 07:10:46PM +0200, Gleb Natapov wrote: > On Fri, Jan 07, 2011 at 02:55:06AM -0600, Milton Miller wrote: > > We sometimes need to map between the virtio device and > > the given pci device. One such use is OS installer that > > gets the boot pci device from BIOS and needs to > > find the relevant block device. Since it can't, > > installation fails. > > > > Instead of creating a top-level devices/virtio-pci > > directory, create each device under the corresponding > > pci device node. Symlinks to all virtio-pci > > devices can be found under the pci driver link in > > bus/pci/drivers/virtio-pci/devices, and all virtio > > devices under drivers/bus/virtio/devices. > > > > Signed-off-by: Milton Miller > Acked-by: Gleb Natapov Rusty, any comments? We are going to tell the installer guys that this is the interface, would be nice to know that the patch is queued before we do. > > --- > > > > This is an alternative to the patch by Michael S. Tsirkin > > titled "virtio-pci: add softlinks between virtio and pci" > > https://patchwork.kernel.org/patch/454581/ > > > > It creates simpler code, uses less memory, and should > > be even easier use by the installer as it won't have to > > know a virtio symlink to follow (just follow none). > > > > Compile tested only as I don't have kvm setup. > > > > > > diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c > > index ef8d9d5..4fb5b2b 100644 > > --- a/drivers/virtio/virtio_pci.c > > +++ b/drivers/virtio/virtio_pci.c > > @@ -96,11 +96,6 @@ static struct pci_device_id virtio_pci_id_table[] = { > > > > MODULE_DEVICE_TABLE(pci, virtio_pci_id_table); > > > > -/* A PCI device has it's own struct device and so does a virtio device so > > - * we create a place for the virtio devices to show up in sysfs. I think it > > - * would make more sense for virtio to not insist on having it's own device. */ > > -static struct device *virtio_pci_root; > > - > > /* Convert a generic virtio device to our structure */ > > static struct virtio_pci_device *to_vp_device(struct virtio_device *vdev) > > { > > @@ -629,7 +624,7 @@ static int __devinit virtio_pci_probe(struct pci_dev *pci_dev, > > if (vp_dev == NULL) > > return -ENOMEM; > > > > - vp_dev->vdev.dev.parent = virtio_pci_root; > > + vp_dev->vdev.dev.parent = &pci_dev->dev; > > vp_dev->vdev.dev.release = virtio_pci_release_dev; > > vp_dev->vdev.config = &virtio_pci_config_ops; > > vp_dev->pci_dev = pci_dev; > > @@ -717,17 +712,7 @@ static struct pci_driver virtio_pci_driver = { > > > > static int __init virtio_pci_init(void) > > { > > - int err; > > - > > - virtio_pci_root = root_device_register("virtio-pci"); > > - if (IS_ERR(virtio_pci_root)) > > - return PTR_ERR(virtio_pci_root); > > - > > - err = pci_register_driver(&virtio_pci_driver); > > - if (err) > > - root_device_unregister(virtio_pci_root); > > - > > - return err; > > + return pci_register_driver(&virtio_pci_driver); > > } > > > > module_init(virtio_pci_init); > > @@ -735,7 +720,6 @@ module_init(virtio_pci_init); > > static void __exit virtio_pci_exit(void) > > { > > pci_unregister_driver(&virtio_pci_driver); > > - root_device_unregister(virtio_pci_root); > > } > > > > module_exit(virtio_pci_exit); > > -- > Gleb.