Re: [RFC v3 06/19] vfio-user: Define type vfio_user_pci_dev_info

[Alex Williamson]

On Mon,  8 Nov 2021 16:46:34 -0800
John Johnson <john.g.johnson@oracle.com> wrote:

> New class for vfio-user with its class and instance
> constructors and destructors, and its pci ops.
> 
> Signed-off-by: Elena Ufimtseva <elena.ufimtseva@oracle.com>
> Signed-off-by: John G Johnson <john.g.johnson@oracle.com>
> Signed-off-by: Jagannathan Raman <jag.raman@oracle.com>
> ---
>  hw/vfio/pci.h   |  9 ++++++
>  hw/vfio/pci.c   | 97 
> +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  hw/vfio/Kconfig | 10 ++++++
>  3 files changed, 116 insertions(+)
> 
> diff --git a/hw/vfio/pci.h b/hw/vfio/pci.h
> index bbc78aa..08ac647 100644
> --- a/hw/vfio/pci.h
> +++ b/hw/vfio/pci.h
> @@ -187,6 +187,15 @@ struct VFIOKernPCIDevice {
>      VFIOPCIDevice device;
>  };
>  
> +#define TYPE_VFIO_USER_PCI "vfio-user-pci"
> +OBJECT_DECLARE_SIMPLE_TYPE(VFIOUserPCIDevice, VFIO_USER_PCI)
> +
> +struct VFIOUserPCIDevice {
> +    VFIOPCIDevice device;
> +    char *sock_name;
> +    bool secure_dma; /* disable shared mem for DMA */
> +};
> +
>  /* Use uin32_t for vendor & device so PCI_ANY_ID expands and cannot match hw 
> */
>  static inline bool vfio_pci_is(VFIOPCIDevice *vdev, uint32_t vendor, 
> uint32_t device)
>  {
> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
> index 6e2ce35..fa3e028 100644
> --- a/hw/vfio/pci.c
> +++ b/hw/vfio/pci.c
> @@ -19,6 +19,7 @@
>   */
>  
>  #include "qemu/osdep.h"
> +#include CONFIG_DEVICES
>  #include <linux/vfio.h>
>  #include <sys/ioctl.h>
>  
> @@ -3438,3 +3439,99 @@ struct VFIOValidOps vfio_pci_valid_ops = {
>      .validate_get_region_info = vfio_pci_valid_region_info,
>      .validate_get_irq_info = vfio_pci_valid_irq_info,
>  };
> +
> +
> +#ifdef CONFIG_VFIO_USER_PCI
> +
> +/*
> + * vfio-user routines.
> + */
> +
> +/*
> + * Emulated devices don't use host hot reset
> + */
> +static int vfio_user_pci_no_reset(VFIODevice *vbasedev)
> +{
> +    error_printf("vfio-user - no hot reset\n");
> +    return 0;
> +}
> +
> +static void vfio_user_pci_not_needed(VFIODevice *vbasedev)
> +{
> +    vbasedev->needs_reset = false;
> +}

Seems like we should make some of these optional rather than stubbing
dummy functions.

> +
> +static VFIODeviceOps vfio_user_pci_ops = {
> +    .vfio_compute_needs_reset = vfio_user_pci_not_needed,
> +    .vfio_hot_reset_multi = vfio_user_pci_no_reset,
> +    .vfio_eoi = vfio_intx_eoi,
> +    .vfio_get_object = vfio_pci_get_object,
> +    .vfio_save_config = vfio_pci_save_config,
> +    .vfio_load_config = vfio_pci_load_config,
> +};
> +
> +static void vfio_user_pci_realize(PCIDevice *pdev, Error **errp)
> +{
> +    ERRP_GUARD();
> +    VFIOUserPCIDevice *udev = VFIO_USER_PCI(pdev);
> +    VFIOPCIDevice *vdev = VFIO_PCI_BASE(pdev);
> +    VFIODevice *vbasedev = &vdev->vbasedev;
> +
> +    /*
> +     * TODO: make option parser understand SocketAddress
> +     * and use that instead of having scalar options
> +     * for each socket type.
> +     */
> +    if (!udev->sock_name) {
> +        error_setg(errp, "No socket specified");
> +        error_append_hint(errp, "Use -device vfio-user-pci,socket=<name>\n");
> +        return;
> +    }
> +
> +    vbasedev->name = g_strdup_printf("VFIO user <%s>", udev->sock_name);
> +    vbasedev->dev = DEVICE(vdev);
> +    vbasedev->fd = -1;
> +    vbasedev->type = VFIO_DEVICE_TYPE_PCI;
> +    vbasedev->no_mmap = false;

Why hard coded rather than a property?  This is a useful debugging
feature to be able to trap all device accesses.  The device should work
either way.

> +    vbasedev->ops = &vfio_user_pci_ops;
> +    vbasedev->valid_ops = &vfio_pci_valid_ops;
> +
> +}
> +
> +static void vfio_user_instance_finalize(Object *obj)
> +{
> +}
> +
> +static Property vfio_user_pci_dev_properties[] = {
> +    DEFINE_PROP_STRING("socket", VFIOUserPCIDevice, sock_name),
> +    DEFINE_PROP_BOOL("secure-dma", VFIOUserPCIDevice, secure_dma, false),

Add this when it means something.  Thanks,

Alex

> +    DEFINE_PROP_END_OF_LIST(),
> +};
> +
> +static void vfio_user_pci_dev_class_init(ObjectClass *klass, void *data)
> +{
> +    DeviceClass *dc = DEVICE_CLASS(klass);
> +    PCIDeviceClass *pdc = PCI_DEVICE_CLASS(klass);
> +
> +    device_class_set_props(dc, vfio_user_pci_dev_properties);
> +    dc->desc = "VFIO over socket PCI device assignment";
> +    pdc->realize = vfio_user_pci_realize;
> +}
> +
> +static const TypeInfo vfio_user_pci_dev_info = {
> +    .name = TYPE_VFIO_USER_PCI,
> +    .parent = TYPE_VFIO_PCI_BASE,
> +    .instance_size = sizeof(VFIOUserPCIDevice),
> +    .class_init = vfio_user_pci_dev_class_init,
> +    .instance_init = vfio_instance_init,
> +    .instance_finalize = vfio_user_instance_finalize,
> +};
> +
> +static void register_vfio_user_dev_type(void)
> +{
> +    type_register_static(&vfio_user_pci_dev_info);
> +}
> +
> +type_init(register_vfio_user_dev_type)
> +
> +#endif /* VFIO_USER_PCI */
> diff --git a/hw/vfio/Kconfig b/hw/vfio/Kconfig
> index 7cdba05..301894e 100644
> --- a/hw/vfio/Kconfig
> +++ b/hw/vfio/Kconfig
> @@ -2,6 +2,10 @@ config VFIO
>      bool
>      depends on LINUX
>  
> +config VFIO_USER
> +    bool
> +    depends on VFIO
> +
>  config VFIO_PCI
>      bool
>      default y
> @@ -9,6 +13,12 @@ config VFIO_PCI
>      select EDID
>      depends on LINUX && PCI
>  
> +config VFIO_USER_PCI
> +    bool
> +    default y
> +    select VFIO_USER
> +    depends on VFIO_PCI
> +
>  config VFIO_CCW
>      bool
>      default y