On 6/3/24 08:10, Zhenzhong Duan wrote:
> Introduce HostIOMMUDevice as an abstraction of host IOMMU device.
>
> Introduce .realize() to initialize HostIOMMUDevice further after
> instance init.
>
> Introduce a macro CONFIG_HOST_IOMMU_DEVICE to define the usage
> for VFIO, and VDPA in the future.
>
> Suggested-by: Cédric Le Goater <c...@redhat.com>
> Signed-off-by: Zhenzhong Duan <zhenzhong.d...@intel.com>
> ---
> MAINTAINERS | 2 ++
> include/sysemu/host_iommu_device.h | 51 ++++++++++++++++++++++++++++++
> backends/host_iommu_device.c | 30 ++++++++++++++++++
> backends/Kconfig | 5 +++
> backends/meson.build | 1 +
> 5 files changed, 89 insertions(+)
> create mode 100644 include/sysemu/host_iommu_device.h
> create mode 100644 backends/host_iommu_device.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 448dc951c5..1cf2b25beb 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -2196,6 +2196,8 @@ M: Zhenzhong Duan <zhenzhong.d...@intel.com>
> S: Supported
> F: backends/iommufd.c
> F: include/sysemu/iommufd.h
> +F: backends/host_iommu_device.c
> +F: include/sysemu/host_iommu_device.h
> F: include/qemu/chardev_open.h
> F: util/chardev_open.c
> F: docs/devel/vfio-iommufd.rst
> diff --git a/include/sysemu/host_iommu_device.h
> b/include/sysemu/host_iommu_device.h
> new file mode 100644
> index 0000000000..2b58a94d62
> --- /dev/null
> +++ b/include/sysemu/host_iommu_device.h
> @@ -0,0 +1,51 @@
> +/*
> + * Host IOMMU device abstract declaration
> + *
> + * Copyright (C) 2024 Intel Corporation.
> + *
> + * Authors: Zhenzhong Duan <zhenzhong.d...@intel.com>
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2. See
> + * the COPYING file in the top-level directory.
> + */
> +
> +#ifndef HOST_IOMMU_DEVICE_H
> +#define HOST_IOMMU_DEVICE_H
> +
> +#include "qom/object.h"
> +#include "qapi/error.h"
> +
> +#define TYPE_HOST_IOMMU_DEVICE "host-iommu-device"
> +OBJECT_DECLARE_TYPE(HostIOMMUDevice, HostIOMMUDeviceClass, HOST_IOMMU_DEVICE)
> +
> +struct HostIOMMUDevice {
> + Object parent_obj;
> +};
> +
> +/**
> + * struct HostIOMMUDeviceClass - The base class for all host IOMMU devices.
> + *
> + * Different type of host devices (e.g., VFIO or VDPA device) or devices
s/type/types
> + * with different backend (e.g., VFIO legacy container or IOMMUFD backend)
> + * can have different sub-classes.
will have different implementations of the HostIOMMUDeviceClass?
> + */
> +struct HostIOMMUDeviceClass {
> + ObjectClass parent_class;
> +
> + /**
> + * @realize: initialize host IOMMU device instance further.
> + *
> + * Mandatory callback.
> + *
> + * @hiod: pointer to a host IOMMU device instance.
> + *
> + * @opaque: pointer to agent device of this host IOMMU device,
> + * i.e., for VFIO, pointer to VFIODevice
VFIO base device or VDPA device?
> + *
> + * @errp: pass an Error out when realize fails.
> + *
> + * Returns: true on success, false on failure.
> + */
> + bool (*realize)(HostIOMMUDevice *hiod, void *opaque, Error **errp);
I think I would introduce the get_cap API here as well to give a minimal
consistency to the class API.
> +};
> +#endif
> diff --git a/backends/host_iommu_device.c b/backends/host_iommu_device.c
> new file mode 100644
> index 0000000000..41f2fdce20
> --- /dev/null
> +++ b/backends/host_iommu_device.c
> @@ -0,0 +1,30 @@
> +/*
> + * Host IOMMU device abstract
> + *
> + * Copyright (C) 2024 Intel Corporation.
> + *
> + * Authors: Zhenzhong Duan <zhenzhong.d...@intel.com>
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2. See
> + * the COPYING file in the top-level directory.
> + */
> +
> +#include "qemu/osdep.h"
> +#include "sysemu/host_iommu_device.h"
> +
> +OBJECT_DEFINE_ABSTRACT_TYPE(HostIOMMUDevice,
> + host_iommu_device,
> + HOST_IOMMU_DEVICE,
> + OBJECT)
> +
> +static void host_iommu_device_class_init(ObjectClass *oc, void *data)
> +{
> +}
> +
> +static void host_iommu_device_init(Object *obj)
> +{
> +}
> +
> +static void host_iommu_device_finalize(Object *obj)
> +{
> +}
> diff --git a/backends/Kconfig b/backends/Kconfig
> index 2cb23f62fa..34ab29e994 100644
> --- a/backends/Kconfig
> +++ b/backends/Kconfig
> @@ -3,3 +3,8 @@ source tpm/Kconfig
> config IOMMUFD
> bool
> depends on VFIO
> +
> +config HOST_IOMMU_DEVICE
> + bool
> + default y
> + depends on VFIO
> diff --git a/backends/meson.build b/backends/meson.build
> index 8b2b111497..2e975d641e 100644
> --- a/backends/meson.build
> +++ b/backends/meson.build
> @@ -25,6 +25,7 @@ if have_vhost_user
> endif
> system_ss.add(when: 'CONFIG_VIRTIO_CRYPTO', if_true:
> files('cryptodev-vhost.c'))
> system_ss.add(when: 'CONFIG_IOMMUFD', if_true: files('iommufd.c'))
> +system_ss.add(when: 'CONFIG_HOST_IOMMU_DEVICE', if_true:
> files('host_iommu_device.c'))
> if have_vhost_user_crypto
> system_ss.add(when: 'CONFIG_VIRTIO_CRYPTO', if_true:
> files('cryptodev-vhost-user.c'))
> endif
