Merge remote-tracking branch 'remotes/awilliam/tags/vfio-update-20201123.0' into staging

VFIO update 2020-11-23

 * Enable pre-copy dirty page tracking by default (Kirti Wankhede)

 * Mark migration as experimental (Alex Williamson)

# gpg: Signature made Mon 23 Nov 2020 17:10:58 GMT
# gpg:                using RSA key 239B9B6E3BB08B22
# gpg: Good signature from "Alex Williamson <alex.williamson@redhat.com>" [full]
# gpg:                 aka "Alex Williamson <alex@shazbot.org>" [full]
# gpg:                 aka "Alex Williamson <alwillia@redhat.com>" [full]
# gpg:                 aka "Alex Williamson <alex.l.williamson@gmail.com>" [full]
# Primary key fingerprint: 42F6 C04E 540B D1A9 9E7B  8A90 239B 9B6E 3BB0 8B22

* remotes/awilliam/tags/vfio-update-20201123.0:
  vfio: Change default dirty pages tracking behavior during migration
  vfio: Make migration support experimental

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

4 files changed, 15 insertions, 5 deletions

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index c1fdbf17f2..6ff1daa763 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -311,7 +311,7 @@ bool vfio_mig_active(void)
     return true;
 }
 
-static bool vfio_devices_all_stopped_and_saving(VFIOContainer *container)
+static bool vfio_devices_all_saving(VFIOContainer *container)
 {
     VFIOGroup *group;
     VFIODevice *vbasedev;
@@ -329,8 +329,11 @@ static bool vfio_devices_all_stopped_and_saving(VFIOContainer *container)
                 return false;
             }
 
-            if ((migration->device_state & VFIO_DEVICE_STATE_SAVING) &&
-                !(migration->device_state & VFIO_DEVICE_STATE_RUNNING)) {
+            if (migration->device_state & VFIO_DEVICE_STATE_SAVING) {
+                if ((vbasedev->pre_copy_dirty_page_tracking == ON_OFF_AUTO_OFF)
+                    && (migration->device_state & VFIO_DEVICE_STATE_RUNNING)) {
+                        return false;
+                }
                 continue;
             } else {
                 return false;
@@ -1125,7 +1128,7 @@ static void vfio_listerner_log_sync(MemoryListener *listener,
         return;
     }
 
-    if (vfio_devices_all_stopped_and_saving(container)) {
+    if (vfio_devices_all_saving(container)) {
         vfio_sync_dirty_bitmap(container, section);
     }
 }
diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c
index 55261562d4..00daa50ed8 100644
--- a/hw/vfio/migration.c
+++ b/hw/vfio/migration.c
@@ -882,7 +882,7 @@ int vfio_migration_probe(VFIODevice *vbasedev, Error **errp)
     Error *local_err = NULL;
     int ret = -ENOTSUP;
 
-    if (!container->dirty_pages_supported) {
+    if (!vbasedev->enable_migration || !container->dirty_pages_supported) {
         goto add_blocker;
     }
 
diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index 58c0ce8971..51dc373695 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -3182,6 +3182,9 @@ static void vfio_instance_init(Object *obj)
 static Property vfio_pci_dev_properties[] = {
     DEFINE_PROP_PCI_HOST_DEVADDR("host", VFIOPCIDevice, host),
     DEFINE_PROP_STRING("sysfsdev", VFIOPCIDevice, vbasedev.sysfsdev),
+    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("display", VFIOPCIDevice,
                             display, ON_OFF_AUTO_OFF),
     DEFINE_PROP_UINT32("xres", VFIOPCIDevice, display_xres, 0),
@@ -3194,6 +3197,8 @@ static Property vfio_pci_dev_properties[] = {
                     VFIO_FEATURE_ENABLE_REQ_BIT, true),
     DEFINE_PROP_BIT("x-igd-opregion", VFIOPCIDevice, features,
                     VFIO_FEATURE_ENABLE_IGD_OPREGION_BIT, false),
+    DEFINE_PROP_BOOL("x-enable-migration", VFIOPCIDevice,
+                     vbasedev.enable_migration, false),
     DEFINE_PROP_BOOL("x-no-mmap", VFIOPCIDevice, vbasedev.no_mmap, false),
     DEFINE_PROP_BOOL("x-balloon-allowed", VFIOPCIDevice,
                      vbasedev.ram_block_discard_allowed, false),
diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
index baeb4dcff1..6141162d7a 100644
--- a/include/hw/vfio/vfio-common.h
+++ b/include/hw/vfio/vfio-common.h
@@ -123,12 +123,14 @@ typedef struct VFIODevice {
     bool needs_reset;
     bool no_mmap;
     bool ram_block_discard_allowed;
+    bool enable_migration;
     VFIODeviceOps *ops;
     unsigned int num_irqs;
     unsigned int num_regions;
     unsigned int flags;
     VFIOMigration *migration;
     Error *migration_blocker;
+    OnOffAuto pre_copy_dirty_page_tracking;
 } VFIODevice;
 
 struct VFIODeviceOps {