qemu/vfio-container-Implement-HostIOMMUDeviceClass-realiz.patch

From c66d22fa4ee9f6f38193256d7ce1494c32e10581 Mon Sep 17 00:00:00 2001
From: Zhenzhong Duan <zhenzhong.duan@intel.com>
Date: Wed, 5 Jun 2024 16:30:32 +0800
Subject: [PATCH] vfio/container: Implement HostIOMMUDeviceClass::realize()
 handler

The realize function populates the capabilities. For now only the
aw_bits caps is computed for legacy backend.

Introduce a helper function vfio_device_get_aw_bits() which calls
range_get_last_bit() to get host aw_bits and package it in
HostIOMMUDeviceCaps for query with .get_cap(). This helper will
also be used by iommufd backend.

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
---
 hw/vfio/container.c           | 20 +++++++++++++++++++-
 hw/vfio/helpers.c             | 17 +++++++++++++++++
 include/hw/vfio/vfio-common.h |  1 +
 3 files changed, 37 insertions(+), 1 deletion(-)

diff --git a/hw/vfio/container.c b/hw/vfio/container.c
index dcf49af2d0..fbe2bc50d4 100644
--- a/hw/vfio/container.c
+++ b/hw/vfio/container.c
@@ -1250,6 +1250,24 @@ static void vfio_iommu_legacy_class_init(ObjectClass *klass, void *data)
     vioc->pci_hot_reset = vfio_legacy_pci_hot_reset;
 };
 
+static bool hiod_legacy_vfio_realize(HostIOMMUDevice *hiod, void *opaque,
+                                     Error **errp)
+{
+    VFIODevice *vdev = opaque;
+
+    hiod->name = g_strdup(vdev->name);
+    hiod->caps.aw_bits = vfio_device_get_aw_bits(vdev);
+
+    return true;
+}
+
+static void hiod_legacy_vfio_class_init(ObjectClass *oc, void *data)
+{
+    HostIOMMUDeviceClass *hioc = HOST_IOMMU_DEVICE_CLASS(oc);
+
+    hioc->realize = hiod_legacy_vfio_realize;
+};
+
 static const TypeInfo types[] = {
     {
         .name = TYPE_VFIO_IOMMU_LEGACY,
@@ -1258,8 +1276,8 @@ static const TypeInfo types[] = {
     }, {
         .name = TYPE_HOST_IOMMU_DEVICE_LEGACY_VFIO,
         .parent = TYPE_HOST_IOMMU_DEVICE,
+        .class_init = hiod_legacy_vfio_class_init,
     }
-
 };
 
 DEFINE_TYPES(types)
diff --git a/hw/vfio/helpers.c b/hw/vfio/helpers.c
index 6789870802..35b8e42304 100644
--- a/hw/vfio/helpers.c
+++ b/hw/vfio/helpers.c
@@ -663,3 +663,20 @@ void vfio_device_init(VFIODevice *vbasedev, int type, VFIODeviceOps *ops,
 
     vbasedev->ram_block_discard_allowed = ram_discard;
 }
+
+int vfio_device_get_aw_bits(VFIODevice *vdev)
+{
+    /*
+     * iova_ranges is a sorted list. For old kernels that support
+     * VFIO but not support query of iova ranges, iova_ranges is NULL,
+     * in this case HOST_IOMMU_DEVICE_CAP_AW_BITS_MAX(64) is returned.
+     */
+    GList *l = g_list_last(vdev->bcontainer->iova_ranges);
+
+    if (l) {
+        Range *range = l->data;
+        return range_get_last_bit(range) + 1;
+    }
+
+    return HOST_IOMMU_DEVICE_CAP_AW_BITS_MAX;
+}
diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
index 2cfc8521cd..376b8350b9 100644
--- a/include/hw/vfio/vfio-common.h
+++ b/include/hw/vfio/vfio-common.h
@@ -277,4 +277,5 @@ int vfio_device_get_name(VFIODevice *vbasedev, Error **errp);
 void vfio_device_set_fd(VFIODevice *vbasedev, const char *str, Error **errp);
 void vfio_device_init(VFIODevice *vbasedev, int type, VFIODeviceOps *ops,
                       DeviceState *dev, bool ram_discard);
+int vfio_device_get_aw_bits(VFIODevice *vdev);
 #endif /* HW_VFIO_VFIO_COMMON_H */
-- 
2.41.0.windows.1