From: Steve Sistare <steven.sistare@oracle.com>
Date: Tue, 10 Jun 2025 15:39:20 +0000 (-0700)
Subject: vfio/container: mdev cpr blocker
X-Git-Tag: v10.1.0-rc0~53^2~11
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=dac0dd68d9b150a6aa334ab8ee9aeba011d54b32;p=thirdparty%2Fqemu.git

vfio/container: mdev cpr blocker

During CPR, after VFIO_DMA_UNMAP_FLAG_VADDR, the vaddr is temporarily
invalid, so mediated devices cannot be supported.  Add a blocker for them.
This restriction will not apply to iommufd containers when CPR is added
for them in a future patch.

Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/qemu-devel/1749569991-25171-8-git-send-email-steven.sistare@oracle.com
[ clg: Fixed context change in VFIODevice ]
Signed-off-by: Cédric Le Goater <clg@redhat.com>
---

diff --git a/hw/vfio/container.c b/hw/vfio/container.c
index 936ce37f190..3e8d645ebbd 100644
--- a/hw/vfio/container.c
+++ b/hw/vfio/container.c
@@ -987,6 +987,13 @@ static bool vfio_legacy_attach_device(const char *name, VFIODevice *vbasedev,
         goto device_put_exit;
     }
 
+    if (vbasedev->mdev) {
+        error_setg(&vbasedev->cpr.mdev_blocker,
+                   "CPR does not support vfio mdev %s", vbasedev->name);
+        migrate_add_blocker_modes(&vbasedev->cpr.mdev_blocker, &error_fatal,
+                                  MIG_MODE_CPR_TRANSFER, -1);
+    }
+
     return true;
 
 device_put_exit:
@@ -1004,6 +1011,7 @@ static void vfio_legacy_detach_device(VFIODevice *vbasedev)
 
     vfio_device_unprepare(vbasedev);
 
+    migrate_del_blocker(&vbasedev->cpr.mdev_blocker);
     object_unref(vbasedev->hiod);
     vfio_device_put(vbasedev);
     vfio_group_put(group);
diff --git a/include/hw/vfio/vfio-cpr.h b/include/hw/vfio/vfio-cpr.h
index 04624475f87..b83dd427518 100644
--- a/include/hw/vfio/vfio-cpr.h
+++ b/include/hw/vfio/vfio-cpr.h
@@ -22,6 +22,9 @@ typedef struct VFIOContainerCPR {
                          void *vaddr, bool readonly, MemoryRegion *mr);
 } VFIOContainerCPR;
 
+typedef struct VFIODeviceCPR {
+    Error *mdev_blocker;
+} VFIODeviceCPR;
 
 bool vfio_legacy_cpr_register_container(struct VFIOContainer *container,
                                         Error **errp);
diff --git a/include/hw/vfio/vfio-device.h b/include/hw/vfio/vfio-device.h
index 9793b2dba0c..f39259406bd 100644
--- a/include/hw/vfio/vfio-device.h
+++ b/include/hw/vfio/vfio-device.h
@@ -28,6 +28,7 @@
 #endif
 #include "system/system.h"
 #include "hw/vfio/vfio-container-base.h"
+#include "hw/vfio/vfio-cpr.h"
 #include "system/host_iommu_device.h"
 #include "system/iommufd.h"
 
@@ -86,6 +87,7 @@ typedef struct VFIODevice {
     QLIST_ENTRY(VFIODevice) hwpt_next;
     struct vfio_region_info **reginfo;
     int *region_fds;
+    VFIODeviceCPR cpr;
 } VFIODevice;
 
 struct VFIODeviceOps {