qemu/vfio-common-Allow-disabling-device-dirty-page-tracki.patch

From b0fe5a6794c5403f4ab9859ec2ced338246690bd Mon Sep 17 00:00:00 2001
From: Joao Martins <joao.m.martins@oracle.com>
Date: Mon, 22 Jul 2024 22:13:26 +0100
Subject: [PATCH] vfio/common: Allow disabling device dirty page tracking

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>
Reviewed-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
---
 hw/vfio/common.c              | 3 +++
 hw/vfio/migration.c           | 4 +++-
 hw/vfio/pci.c                 | 3 +++
 include/hw/vfio/vfio-common.h | 1 +
 4 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index 65e1c9f810..a8bc1c6055 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -208,6 +208,9 @@ 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 db128204af..3924beb289 100644
--- a/hw/vfio/migration.c
+++ b/hw/vfio/migration.c
@@ -945,7 +945,9 @@ bool vfio_migration_realize(VFIODevice *vbasedev, Error **errp)
         return !vfio_block_migration(vbasedev, err, errp);
     }
 
-    if (!vbasedev->dirty_pages_supported && !vbasedev->iommu_dirty_tracking) {
+    if ((!vbasedev->dirty_pages_supported ||
+         vbasedev->device_dirty_page_tracking == ON_OFF_AUTO_OFF) &&
+        !vbasedev->iommu_dirty_tracking) {
         if (vbasedev->enable_migration == ON_OFF_AUTO_AUTO) {
             error_setg(&err,
                        "%s: VFIO device doesn't support device and "
diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index 19211f4368..f585f285f4 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -3350,6 +3350,9 @@ 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),
diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
index 22a7386591..abae8655c4 100644
--- a/include/hw/vfio/vfio-common.h
+++ b/include/hw/vfio/vfio-common.h
@@ -147,6 +147,7 @@ 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;
     bool iommu_dirty_tracking;
-- 
2.41.0.windows.1