backends/iommufd: Retrieve PASID width from iommufd_backend_get_device_info()

Retrieve PASID width from iommufd_backend_get_device_info() and store it
in HostIOMMUDeviceCaps for later use.

Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Zhangfei Gao <zhangfei.gao@linaro.org>
Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Shameer Kolothum <skolothumtho@nvidia.com>
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Message-id: 20260126104342.253965-33-skolothumtho@nvidia.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

backends/iommufd.c

@@ -389,7 +389,8 @@ bool iommufd_backend_get_dirty_bitmap(IOMMUFDBackend *be,
 
 bool iommufd_backend_get_device_info(IOMMUFDBackend *be, uint32_t devid,
                                      uint32_t *type, void *data, uint32_t len,
-                                     uint64_t *caps, Error **errp)
+                                     uint64_t *caps, uint8_t *max_pasid_log2,
+                                     Error **errp)
 {
     struct iommu_hw_info info = {
         .size = sizeof(info),
@@ -408,6 +409,9 @@ bool iommufd_backend_get_device_info(IOMMUFDBackend *be, uint32_t devid,
     g_assert(caps);
     *caps = info.out_capabilities;
 
+    if (max_pasid_log2) {
+        *max_pasid_log2 = info.out_max_pasid_log2;
+    }
     return true;
 }
 

hw/arm/smmuv3-accel.c

@@ -121,7 +121,8 @@ smmuv3_accel_hw_compatible(SMMUv3State *s, HostIOMMUDeviceIOMMUFD *idev,
     uint64_t caps;
 
     if (!iommufd_backend_get_device_info(idev->iommufd, idev->devid, &data_type,
-                                         &info, sizeof(info), &caps, errp)) {
+                                         &info, sizeof(info), &caps, NULL,
+                                         errp)) {
         return false;
     }
 

hw/vfio/iommufd.c

@@ -398,7 +398,7 @@ static bool iommufd_cdev_autodomains_get(VFIODevice *vbasedev,
      */
     if (!iommufd_backend_get_device_info(vbasedev->iommufd, vbasedev->devid,
                                          &type, &caps, sizeof(caps), &hw_caps,
-                                         errp)) {
+                                         NULL, errp)) {
         return false;
     }
 
@@ -939,19 +939,21 @@ static bool hiod_iommufd_vfio_realize(HostIOMMUDevice *hiod, void *opaque,
     HostIOMMUDeviceCaps *caps = &hiod->caps;
     VendorCaps *vendor_caps = &caps->vendor_caps;
     enum iommu_hw_info_type type;
+    uint8_t max_pasid_log2;
     uint64_t hw_caps;
 
     hiod->agent = opaque;
 
     if (!iommufd_backend_get_device_info(vdev->iommufd, vdev->devid, &type,
                                          vendor_caps, sizeof(*vendor_caps),
-                                         &hw_caps, errp)) {
+                                         &hw_caps, &max_pasid_log2, errp)) {
         return false;
     }
 
     hiod->name = g_strdup(vdev->name);
     caps->type = type;
     caps->hw_caps = hw_caps;
+    caps->max_pasid_log2 = max_pasid_log2;
 
     idev = HOST_IOMMU_DEVICE_IOMMUFD(hiod);
     idev->iommufd = vdev->iommufd;

include/system/host_iommu_device.h

@@ -30,6 +30,8 @@ typedef union VendorCaps {
  * @hw_caps: host platform IOMMU capabilities (e.g. on IOMMUFD this represents
  *           the @out_capabilities value returned from IOMMU_GET_HW_INFO ioctl)
  *
+ * @max_pasid_log2: width of PASIDs supported by host IOMMU device
+ *
  * @vendor_caps: host platform IOMMU vendor specific capabilities (e.g. on
  *               IOMMUFD this represents a user-space buffer filled by kernel
  *               with host IOMMU @type specific hardware information data)
@@ -37,6 +39,7 @@ typedef union VendorCaps {
 typedef struct HostIOMMUDeviceCaps {
     uint32_t type;
     uint64_t hw_caps;
+    uint8_t max_pasid_log2;
     VendorCaps vendor_caps;
 } HostIOMMUDeviceCaps;
 #endif

include/system/iommufd.h

@@ -71,7 +71,8 @@ int iommufd_backend_unmap_dma(IOMMUFDBackend *be, uint32_t ioas_id,
                               hwaddr iova, uint64_t size);
 bool iommufd_backend_get_device_info(IOMMUFDBackend *be, uint32_t devid,
                                      uint32_t *type, void *data, uint32_t len,
-                                     uint64_t *caps, Error **errp);
+                                     uint64_t *caps, uint8_t *max_pasid_log2,
+                                     Error **errp);
 bool iommufd_backend_alloc_hwpt(IOMMUFDBackend *be, uint32_t dev_id,
                                 uint32_t pt_id, uint32_t flags,
                                 uint32_t data_type, uint32_t data_len,