Re: [PATCH rfcv3 05/21] vfio/iommufd: Save vendor specific device info

[Cédric Le Goater]

Hello Zhenzhong,

On 5/21/25 13:14, Zhenzhong Duan wrote:

Some device information returned by ioctl(IOMMU_GET_HW_INFO) are vendor
specific. Save them all in a new defined structure mirroring that vendor
IOMMU's structure, then get_cap() can query those information for
capability.

We can't use the vendor IOMMU's structure directly because they are in
linux/iommufd.h which breaks build on windows.

Suggested-by: Eric Auger <eric.au...@redhat.com>
Suggested-by: Nicolin Chen <nicol...@nvidia.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.d...@intel.com>
---
  include/system/host_iommu_device.h | 12 ++++++++++++
  hw/vfio/iommufd.c                  | 12 ++++++++++++
  2 files changed, 24 insertions(+)

diff --git a/include/system/host_iommu_device.h 
b/include/system/host_iommu_device.h
index 809cced4ba..908bfe32c7 100644
--- a/include/system/host_iommu_device.h
+++ b/include/system/host_iommu_device.h
@@ -15,6 +15,17 @@
  #include "qom/object.h"
  #include "qapi/error.h"

+/* This is mirror of struct iommu_hw_info_vtd */

+typedef struct Vtd_Caps {

please name the struct VtdCaps instead.


Thanks,

C.

+    uint32_t flags;
+    uint64_t cap_reg;
+    uint64_t ecap_reg;
+} Vtd_Caps;
+
+typedef union VendorCaps {
+    Vtd_Caps vtd;
+} VendorCaps;
+
  /**
   * struct HostIOMMUDeviceCaps - Define host IOMMU device capabilities.
   *
@@ -26,6 +37,7 @@
  typedef struct HostIOMMUDeviceCaps {
      uint32_t type;
      uint64_t hw_caps;
+    VendorCaps vendor_caps;
  } HostIOMMUDeviceCaps;

#define TYPE_HOST_IOMMU_DEVICE "host-iommu-device"

diff --git a/hw/vfio/iommufd.c b/hw/vfio/iommufd.c
index d661737c17..5c740222e5 100644
--- a/hw/vfio/iommufd.c
+++ b/hw/vfio/iommufd.c
@@ -834,6 +834,7 @@ static bool hiod_iommufd_vfio_realize(HostIOMMUDevice 
*hiod, void *opaque,
      VFIODevice *vdev = opaque;
      HostIOMMUDeviceIOMMUFD *idev;
      HostIOMMUDeviceCaps *caps = &hiod->caps;
+    VendorCaps *vendor_caps = &caps->vendor_caps;
      enum iommu_hw_info_type type;
      union {
          struct iommu_hw_info_vtd vtd;
@@ -852,6 +853,17 @@ static bool hiod_iommufd_vfio_realize(HostIOMMUDevice 
*hiod, void *opaque,
      caps->type = type;
      caps->hw_caps = hw_caps;

+ switch (type) {

+    case IOMMU_HW_INFO_TYPE_INTEL_VTD:
+        vendor_caps->vtd.flags = data.vtd.flags;
+        vendor_caps->vtd.cap_reg = data.vtd.cap_reg;
+        vendor_caps->vtd.ecap_reg = data.vtd.ecap_reg;
+        break;
+    case IOMMU_HW_INFO_TYPE_ARM_SMMUV3:
+    case IOMMU_HW_INFO_TYPE_NONE:
+        break;
+    }
+
      idev = HOST_IOMMU_DEVICE_IOMMUFD(hiod);
      idev->iommufd = vdev->iommufd;
      idev->devid = vdev->devid;