Re: [PATCH v3 15/19] hw/pci: Introduce pci_device_[set|unset]_iommu_device()

["Cédric Le Goater" <clg@redhat.com>]

Hello Zhenzhong,

On 4/29/24 08:50, Zhenzhong Duan wrote:
> From: Yi Liu <yi.l.liu@intel.com>
> 
> pci_device_[set|unset]_iommu_device() call pci_device_get_iommu_bus_devfn()
> to get iommu_bus->iommu_ops and call [set|unset]_iommu_device callback to
> set/unset HostIOMMUDevice for a given PCI device.
> 
> Signed-off-by: Yi Liu <yi.l.liu@intel.com>
> Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com>
> Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
> ---
>   include/hw/pci/pci.h | 38 +++++++++++++++++++++++++++++++++++++-
>   hw/pci/pci.c         | 27 +++++++++++++++++++++++++++
>   2 files changed, 64 insertions(+), 1 deletion(-)
> 
> diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h
> index eaa3fc99d8..849e391813 100644
> --- a/include/hw/pci/pci.h
> +++ b/include/hw/pci/pci.h
> @@ -3,6 +3,7 @@
>   
>   #include "exec/memory.h"
>   #include "sysemu/dma.h"
> +#include "sysemu/host_iommu_device.h"

This include directive pulls a Linux header file <linux/iommufd.h>
which doesn't exist on all platforms, such as windows and it breaks
compile. So,

>   
>   /* PCI includes legacy ISA access.  */
>   #include "hw/isa/isa.h"
> @@ -383,10 +384,45 @@ typedef struct PCIIOMMUOps {
>        *
>        * @devfn: device and function number
>        */
> -   AddressSpace * (*get_address_space)(PCIBus *bus, void *opaque, int devfn);
> +    AddressSpace * (*get_address_space)(PCIBus *bus, void *opaque, int devfn);
> +    /**
> +     * @set_iommu_device: attach a HostIOMMUDevice to a vIOMMU
> +     *
> +     * Optional callback, if not implemented in vIOMMU, then vIOMMU can't
> +     * retrieve host information from the associated HostIOMMUDevice.
> +     *
> +     * @bus: the #PCIBus of the PCI device.
> +     *
> +     * @opaque: the data passed to pci_setup_iommu().
> +     *
> +     * @devfn: device and function number of the PCI device.
> +     *
> +     * @dev: the data structure representing host IOMMU device.
> +     *
> +     * @errp: pass an Error out only when return false
> +     *
> +     * Returns: 0 if HostIOMMUDevice is attached, or else <0 with errp set.
> +     */
> +    int (*set_iommu_device)(PCIBus *bus, void *opaque, int devfn,
> +                            HostIOMMUDevice *dev, Error **errp);
> +    /**
> +     * @unset_iommu_device: detach a HostIOMMUDevice from a vIOMMU
> +     *
> +     * Optional callback.
> +     *
> +     * @bus: the #PCIBus of the PCI device.
> +     *
> +     * @opaque: the data passed to pci_setup_iommu().
> +     *
> +     * @devfn: device and function number of the PCI device.
> +     */
> +    void (*unset_iommu_device)(PCIBus *bus, void *opaque, int devfn);
>   } PCIIOMMUOps;
>   
>   AddressSpace *pci_device_iommu_address_space(PCIDevice *dev);
> +int pci_device_set_iommu_device(PCIDevice *dev, HostIOMMUDevice *hiod,
> +                                Error **errp);

please include a forward declaration for HostIOMMUDevice instead.

Thanks,

C.




> +void pci_device_unset_iommu_device(PCIDevice *dev);
>   
>   /**
>    * pci_setup_iommu: Initialize specific IOMMU handlers for a PCIBus
> diff --git a/hw/pci/pci.c b/hw/pci/pci.c
> index 02a4bb2af6..c3293e9357 100644
> --- a/hw/pci/pci.c
> +++ b/hw/pci/pci.c
> @@ -2742,6 +2742,33 @@ AddressSpace *pci_device_iommu_address_space(PCIDevice *dev)
>       return &address_space_memory;
>   }
>   
> +int pci_device_set_iommu_device(PCIDevice *dev, HostIOMMUDevice *hiod,
> +                                Error **errp)
> +{
> +    PCIBus *iommu_bus;
> +
> +    /* set_iommu_device requires device's direct BDF instead of aliased BDF */
> +    pci_device_get_iommu_bus_devfn(dev, &iommu_bus, NULL, NULL);
> +    if (iommu_bus && iommu_bus->iommu_ops->set_iommu_device) {
> +        return iommu_bus->iommu_ops->set_iommu_device(pci_get_bus(dev),
> +                                                      iommu_bus->iommu_opaque,
> +                                                      dev->devfn, hiod, errp);
> +    }
> +    return 0;
> +}
> +
> +void pci_device_unset_iommu_device(PCIDevice *dev)
> +{
> +    PCIBus *iommu_bus;
> +
> +    pci_device_get_iommu_bus_devfn(dev, &iommu_bus, NULL, NULL);
> +    if (iommu_bus && iommu_bus->iommu_ops->unset_iommu_device) {
> +        return iommu_bus->iommu_ops->unset_iommu_device(pci_get_bus(dev),
> +                                                        iommu_bus->iommu_opaque,
> +                                                        dev->devfn);
> +    }
> +}
> +
>   void pci_setup_iommu(PCIBus *bus, const PCIIOMMUOps *ops, void *opaque)
>   {
>       /*