pci_device_get_viommu_cap() call pci_device_get_iommu_bus_devfn()
to get iommu_bus->iommu_ops and call get_viommu_cap() callback to
get a bitmap with each bit represents a vIOMMU exposed capability.
Suggested-by: Yi Liu <yi.l....@intel.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.d...@intel.com>
---
MAINTAINERS | 1 +
hw/pci/pci.c | 11 +++++++++++
include/hw/iommu.h | 16 ++++++++++++++++
include/hw/pci/pci.h | 23 +++++++++++++++++++++++
4 files changed, 51 insertions(+)
create mode 100644 include/hw/iommu.h
diff --git a/MAINTAINERS b/MAINTAINERS
index 1842c3dd83..d9fc977b81 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2302,6 +2302,7 @@ F: include/system/iommufd.h
F: backends/host_iommu_device.c
F: include/system/host_iommu_device.h
F: include/qemu/chardev_open.h
+F: include/hw/iommu.h
F: util/chardev_open.c
F: docs/devel/vfio-iommufd.rst
diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index c70b5ceeba..df1fb615a8 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -2992,6 +2992,17 @@ void pci_device_unset_iommu_device(PCIDevice *dev)
}
}
+uint64_t pci_device_get_viommu_cap(PCIDevice *dev)
+{
+ PCIBus *iommu_bus;
+
+ pci_device_get_iommu_bus_devfn(dev, &iommu_bus, NULL, NULL);
+ if (iommu_bus && iommu_bus->iommu_ops->get_viommu_cap) {
+ return iommu_bus->iommu_ops->get_viommu_cap(iommu_bus->iommu_opaque);
+ }
+ return 0;
+}
+
int pci_pri_request_page(PCIDevice *dev, uint32_t pasid, bool priv_req,
bool exec_req, hwaddr addr, bool lpig,
uint16_t prgi, bool is_read, bool is_write)
diff --git a/include/hw/iommu.h b/include/hw/iommu.h
new file mode 100644
index 0000000000..e80aaf4431
--- /dev/null
+++ b/include/hw/iommu.h
@@ -0,0 +1,16 @@
+/*
+ * General vIOMMU capabilities, flags, etc
+ *
+ * Copyright (C) 2025 Intel Corporation.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#ifndef HW_IOMMU_H
+#define HW_IOMMU_H
+
+enum {
+ VIOMMU_CAP_STAGE1 = BIT_ULL(0), /* stage1 page table supported */
+};
+
+#endif /* HW_IOMMU_H */
diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h
index df3cc7b875..a11ab14bdc 100644
--- a/include/hw/pci/pci.h
+++ b/include/hw/pci/pci.h
@@ -453,6 +453,19 @@ typedef struct PCIIOMMUOps {
* @devfn: device and function number of the PCI device.
*/
void (*unset_iommu_device)(PCIBus *bus, void *opaque, int devfn);
+ /**
+ * @get_viommu_cap: get vIOMMU capabilities
+ *
+ * Optional callback, if not implemented, then vIOMMU doesn't
+ * support exposing capabilities to other subsystem, e.g., VFIO.
+ * vIOMMU can choose which capabilities to expose.
+ *
+ * @opaque: the data passed to pci_setup_iommu().
+ *
+ * Returns: 64bit bitmap with each bit represents a capability emulated
+ * by VIOMMU_CAP_* in include/hw/iommu.h
+ */
+ uint64_t (*get_viommu_cap)(void *opaque);
/**
* @get_iotlb_info: get properties required to initialize a device IOTLB.
*
@@ -633,6 +646,16 @@ bool pci_device_set_iommu_device(PCIDevice *dev,
HostIOMMUDevice *hiod,
Error **errp);
void pci_device_unset_iommu_device(PCIDevice *dev);
+/**
+ * pci_device_get_viommu_cap: get vIOMMU capabilities.
+ *
+ * Returns a 64bit bitmap with each bit represents a vIOMMU exposed
+ * capability, 0 if vIOMMU doesn't support esposing capabilities.
+ *
+ * @dev: PCI device pointer.
+ */
+uint64_t pci_device_get_viommu_cap(PCIDevice *dev);
+
/**
* pci_iommu_get_iotlb_info: get properties required to initialize a
* device IOTLB.
--
2.47.1
