On Mon, Jan 10, 2011 at 01:22:05PM +0200, Michael S. Tsirkin wrote: > On Mon, Jan 10, 2011 at 01:18:59PM +0200, Gleb Natapov wrote: > > On Sun, Jan 09, 2011 at 05:18:21PM +0200, Michael S. Tsirkin 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 <miltonm@xxxxxxx> > > > > > > OK, this works fine for me. I played with options to add compat > > > softlinks under devices/virtio-pci but we still don't get exactly the > > > same layout and since I don't think anyone actually uses them, it's > > > probably ok to just to the simple thing. > > > > > > Tested/Acked-by: Michael S. Tsirkin <mst@xxxxxxxxxx> > > > > > > Rusty, since this help fix at least one user, any chance this can be put > > > in 2.6.38? OK to backport to -stable? > > > > > > Gleb, could you try this out too? > > > > > With this patch if I have 3 virtio disks for a VM I get: > > /sys/devices/pci0000:00/0000:00:04.0/virtio0/block/vda > > /sys/devices/pci0000:00/0000:00:05.0/virtio1/block/vdb > > /sys/devices/pci0000:00/0000:00:06.0/virtio2/block/vdc > > > > Number after virtio has no much sense. It either should be dropped at all > > or be always zero in case we will support more then one virtio controller > > per pci card. In that case each virtio controller will have directories > > virtio0/virtio1/virtio2... under same pci device directory. > > Yes. But this is the bus name. It must be unique - all devices > also appear under /sys/bus/virtio/devices. > It is very strange king of bus that is spread over several PCI devices :) It doesn't make much sense IMHO, but I can leave with it. > > > > --- > > > > > > > > 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. -- Gleb. _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/virtualization
