[PATCH v5 13/13] vfio/common: Allow disabling device dirty page tracking

[Joao Martins]

The property 'x-pre-copy-dirty-page-tracking' allows disabling the whole
tracking of VF pre-copy phase of dirty page tracking, though it means
that it will only be used at the start of the switchover phase.

Add an option that disables the VF dirty page tracking, and fall
back into container-based dirty page tracking. This also allows to
use IOMMU dirty tracking even on VFs with their own dirty
tracker scheme.

Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
---
 include/hw/vfio/vfio-common.h | 1 +
 hw/vfio/common.c              | 3 +++
 hw/vfio/migration.c           | 3 ++-
 hw/vfio/pci.c                 | 3 +++
 4 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
index 00b9e933449e..61dd48e79b71 100644
--- a/include/hw/vfio/vfio-common.h
+++ b/include/hw/vfio/vfio-common.h
@@ -138,6 +138,7 @@ typedef struct VFIODevice {
     VFIOMigration *migration;
     Error *migration_blocker;
     OnOffAuto pre_copy_dirty_page_tracking;
+    OnOffAuto device_dirty_page_tracking;
     bool dirty_pages_supported;
     bool dirty_tracking;
     HostIOMMUDevice *hiod;
diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index cc14f0e3fe24..070a4a2df020 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -199,6 +199,9 @@ bool vfio_devices_all_device_dirty_tracking(const 
VFIOContainerBase *bcontainer)
     VFIODevice *vbasedev;
 
     QLIST_FOREACH(vbasedev, &bcontainer->device_list, container_next) {
+        if (vbasedev->device_dirty_page_tracking == ON_OFF_AUTO_OFF) {
+            return false;
+        }
         if (!vbasedev->dirty_pages_supported) {
             return false;
         }
diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c
index 63ffa46c9652..88fdc6efbcc9 100644
--- a/hw/vfio/migration.c
+++ b/hw/vfio/migration.c
@@ -1036,7 +1036,8 @@ bool vfio_migration_realize(VFIODevice *vbasedev, Error 
**errp)
         return !vfio_block_migration(vbasedev, err, errp);
     }
 
-    if (!vbasedev->dirty_pages_supported &&
+    if ((!vbasedev->dirty_pages_supported ||
+         vbasedev->device_dirty_page_tracking == ON_OFF_AUTO_OFF) &&
         !iommufd_hwpt_dirty_tracking(vbasedev->hwpt)) {
         if (vbasedev->enable_migration == ON_OFF_AUTO_AUTO) {
             error_setg(&err,
diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index 265d3cb82ffc..2407720c3530 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -3361,6 +3361,9 @@ static Property vfio_pci_dev_properties[] = {
     DEFINE_PROP_ON_OFF_AUTO("x-pre-copy-dirty-page-tracking", VFIOPCIDevice,
                             vbasedev.pre_copy_dirty_page_tracking,
                             ON_OFF_AUTO_ON),
+    DEFINE_PROP_ON_OFF_AUTO("x-device-dirty-page-tracking", VFIOPCIDevice,
+                            vbasedev.device_dirty_page_tracking,
+                            ON_OFF_AUTO_ON),
     DEFINE_PROP_ON_OFF_AUTO("display", VFIOPCIDevice,
                             display, ON_OFF_AUTO_OFF),
     DEFINE_PROP_UINT32("xres", VFIOPCIDevice, display_xres, 0),
-- 
2.17.2