Re: [PATCH] virtio-pci: add softlinks between virtio and pci

Gleb Natapov
2011-01-06T08:52:09Z

On Wed, Jan 05, 2011 at 09:17:11PM +0200, Michael S. Tsirkin 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.
>
> Supply softlinks between these to make it possible.
>
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> ---
>
> Gleb, could you please ack that this patch below
> will be enough to fix the installer issue that
> you see?
>
ACK. With this patch given PCI address from EDD I can find device node
by looking at /sys/devices/pci0000:00/0000:edd_bdf/virtio_device/block/

> drivers/virtio/virtio_pci.c | 18 +++++++++++++++++-
> 1 files changed, 17 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c
> index ef8d9d5..06eb2f8 100644
> --- a/drivers/virtio/virtio_pci.c
> +++ b/drivers/virtio/virtio_pci.c
> @@ -25,6 +25,7 @@
> #include <linux/virtio_pci.h>
> #include <linux/highmem.h>
> #include <linux/spinlock.h>
> +#include <linux/sysfs.h>
>
> MODULE_AUTHOR("Anthony Liguori <aliguori@us.ibm.com>");
> MODULE_DESCRIPTION("virtio-pci");
> @@ -667,8 +668,21 @@ static int __devinit virtio_pci_probe(struct pci_dev *pci_dev,
> if (err)
> goto out_set_drvdata;
>
> - return 0;
> + err = sysfs_create_link(&pci_dev->dev.kobj, &vp_dev->vdev.dev.kobj,
> + "virtio_device");
> + if (err)
> + goto out_register_device;
> +
> + err = sysfs_create_link(&vp_dev->vdev.dev.kobj, &pci_dev->dev.kobj,
> + "bus_device");
> + if (err)
> + goto out_create_link;
>
> + return 0;
> +out_create_link:
> + sysfs_remove_link(&pci_dev->dev.kobj, "virtio_device");
> +out_register_device:
> + unregister_virtio_device(&vp_dev->vdev);
> out_set_drvdata:
> pci_set_drvdata(pci_dev, NULL);
> pci_iounmap(pci_dev, vp_dev->ioaddr);
> @@ -685,6 +699,8 @@ static void __devexit virtio_pci_remove(struct pci_dev *pci_dev)
> {
> struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
>
> + sysfs_remove_link(&vp_dev->vdev.dev.kobj, "bus_device");
> + sysfs_remove_link(&pci_dev->dev.kobj, "virtio_device");
> unregister_virtio_device(&vp_dev->vdev);
> }
>
> --
> 1.7.3.2.91.g446ac

--
Gleb.