Re: [Qemu-devel] [RFC v1 08/18] vfio/pci: add vfio bind/unbind_gpasid implementation

[Auger Eric <eric.auger@redhat.com>]

Hi Liu,

On 7/5/19 1:01 PM, Liu Yi L wrote:
> This patch adds vfio implementation PCIPASIDOps.bind_gpasid/unbind_pasid().
> These two functions are used to propagate guest pasid bind and unbind
> requests to host via vfio container ioctl.
> 
> Cc: Kevin Tian <kevin.tian@intel.com>
> Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
> Cc: Peter Xu <peterx@redhat.com>
> Cc: Eric Auger <eric.auger@redhat.com>
> Cc: Yi Sun <yi.y.sun@linux.intel.com>
> Cc: David Gibson <david@gibson.dropbear.id.au>
> Signed-off-by: Liu Yi L <yi.l.liu@intel.com>
> ---
>  hw/vfio/pci.c | 54 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 54 insertions(+)
> 
> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
> index ab184ad..892b46c 100644
> --- a/hw/vfio/pci.c
> +++ b/hw/vfio/pci.c
> @@ -2744,9 +2744,63 @@ static int vfio_pci_device_request_pasid_free(PCIBus *bus,
>      return ret;
>  }
>  
> +static void vfio_pci_device_bind_gpasid(PCIBus *bus, int32_t devfn,
> +                                     struct gpasid_bind_data *g_bind_data)
> +{
> +    PCIDevice *pdev = bus->devices[devfn];
> +    VFIOPCIDevice *vdev = DO_UPCAST(VFIOPCIDevice, pdev, pdev);
> +    VFIOContainer *container = vdev->vbasedev.group->container;
> +    struct vfio_iommu_type1_bind *bind;
> +    struct vfio_iommu_type1_bind_guest_pasid *bind_guest_pasid;
> +    unsigned long argsz;
> +
> +    argsz = sizeof(*bind) + sizeof(*bind_guest_pasid);
> +    bind = g_malloc0(argsz);
> +    bind->argsz = argsz;
> +    bind->bind_type = VFIO_IOMMU_BIND_GUEST_PASID;
> +    bind_guest_pasid = (struct vfio_iommu_type1_bind_guest_pasid *) &bind->data;
> +    bind_guest_pasid->bind_data = *g_bind_data;
> +
> +    rcu_read_lock();
why do you need the rcu_read_lock?
> +    if (ioctl(container->fd, VFIO_IOMMU_BIND, bind) != 0) {
> +        error_report("vfio_pci_device_bind_gpasid:"
> +                     " bind failed, contanier: %p", container);
container
> +    }
> +    rcu_read_unlock();
> +    g_free(bind);
> +}
> +
> +static void vfio_pci_device_unbind_gpasid(PCIBus *bus, int32_t devfn,
> +                                     struct gpasid_bind_data *g_bind_data)
> +{
> +    PCIDevice *pdev = bus->devices[devfn];
> +    VFIOPCIDevice *vdev = DO_UPCAST(VFIOPCIDevice, pdev, pdev);
> +    VFIOContainer *container = vdev->vbasedev.group->container;
> +    struct vfio_iommu_type1_bind *bind;
> +    struct vfio_iommu_type1_bind_guest_pasid *bind_guest_pasid;
> +    unsigned long argsz;
> +
> +    argsz = sizeof(*bind) + sizeof(*bind_guest_pasid);
> +    bind = g_malloc0(argsz);
> +    bind->argsz = argsz;
> +    bind->bind_type = VFIO_IOMMU_BIND_GUEST_PASID;
> +    bind_guest_pasid = (struct vfio_iommu_type1_bind_guest_pasid *) &bind->data;
> +    bind_guest_pasid->bind_data = *g_bind_data;
> +
> +    rcu_read_lock();
> +    if (ioctl(container->fd, VFIO_IOMMU_UNBIND, bind) != 0) {
> +        error_report("vfio_pci_device_unbind_gpasid:"
> +                     " unbind failed, contanier: %p", container);
container
> +    }
> +    rcu_read_unlock();
> +    g_free(bind);
> +}
> +
>  static PCIPASIDOps vfio_pci_pasid_ops = {
>      .alloc_pasid = vfio_pci_device_request_pasid_alloc,
>      .free_pasid = vfio_pci_device_request_pasid_free,
> +    .bind_gpasid = vfio_pci_device_bind_gpasid,
> +    .unbind_gpasid = vfio_pci_device_unbind_gpasid,
>  };
>  
>  static void vfio_realize(PCIDevice *pdev, Error **errp)
> 

Thanks

Eric