[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[PATCH v11 05/11] vfio/migration: Block multiple devices migration
From: |
Avihai Horon |
Subject: |
[PATCH v11 05/11] vfio/migration: Block multiple devices migration |
Date: |
Thu, 16 Feb 2023 16:36:24 +0200 |
Currently VFIO migration doesn't implement some kind of intermediate
quiescent state in which P2P DMAs are quiesced before stopping or
running the device. This can cause problems in multi-device migration
where the devices are doing P2P DMAs, since the devices are not stopped
together at the same time.
Until such support is added, block migration of multiple devices.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
---
include/hw/vfio/vfio-common.h | 2 ++
hw/vfio/common.c | 53 +++++++++++++++++++++++++++++++++++
hw/vfio/migration.c | 6 ++++
3 files changed, 61 insertions(+)
diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
index e573f5a9f1..56b1683824 100644
--- a/include/hw/vfio/vfio-common.h
+++ b/include/hw/vfio/vfio-common.h
@@ -218,6 +218,8 @@ typedef QLIST_HEAD(VFIOGroupList, VFIOGroup) VFIOGroupList;
extern VFIOGroupList vfio_group_list;
bool vfio_mig_active(void);
+int vfio_block_multiple_devices_migration(Error **errp);
+void vfio_unblock_multiple_devices_migration(void);
int64_t vfio_mig_bytes_transferred(void);
#ifdef CONFIG_LINUX
diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index 3a35f4afad..fe80ccf914 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -41,6 +41,7 @@
#include "qapi/error.h"
#include "migration/migration.h"
#include "migration/misc.h"
+#include "migration/blocker.h"
#include "sysemu/tpm.h"
VFIOGroupList vfio_group_list =
@@ -337,6 +338,58 @@ bool vfio_mig_active(void)
return true;
}
+static Error *multiple_devices_migration_blocker;
+
+static unsigned int vfio_migratable_device_num(void)
+{
+ VFIOGroup *group;
+ VFIODevice *vbasedev;
+ unsigned int device_num = 0;
+
+ QLIST_FOREACH(group, &vfio_group_list, next) {
+ QLIST_FOREACH(vbasedev, &group->device_list, next) {
+ if (vbasedev->migration) {
+ device_num++;
+ }
+ }
+ }
+
+ return device_num;
+}
+
+int vfio_block_multiple_devices_migration(Error **errp)
+{
+ int ret;
+
+ if (multiple_devices_migration_blocker ||
+ vfio_migratable_device_num() <= 1) {
+ return 0;
+ }
+
+ error_setg(&multiple_devices_migration_blocker,
+ "Migration is currently not supported with multiple "
+ "VFIO devices");
+ ret = migrate_add_blocker(multiple_devices_migration_blocker, errp);
+ if (ret < 0) {
+ error_free(multiple_devices_migration_blocker);
+ multiple_devices_migration_blocker = NULL;
+ }
+
+ return ret;
+}
+
+void vfio_unblock_multiple_devices_migration(void)
+{
+ if (!multiple_devices_migration_blocker ||
+ vfio_migratable_device_num() > 1) {
+ return;
+ }
+
+ migrate_del_blocker(multiple_devices_migration_blocker);
+ error_free(multiple_devices_migration_blocker);
+ multiple_devices_migration_blocker = NULL;
+}
+
static bool vfio_devices_all_dirty_tracking(VFIOContainer *container)
{
VFIOGroup *group;
diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c
index e56eef1ee8..8e96999669 100644
--- a/hw/vfio/migration.c
+++ b/hw/vfio/migration.c
@@ -878,6 +878,11 @@ int vfio_migration_probe(VFIODevice *vbasedev, Error
**errp)
goto add_blocker;
}
+ ret = vfio_block_multiple_devices_migration(errp);
+ if (ret) {
+ return ret;
+ }
+
trace_vfio_migration_probe(vbasedev->name, info->index);
g_free(info);
return 0;
@@ -904,6 +909,7 @@ void vfio_migration_finalize(VFIODevice *vbasedev)
qemu_del_vm_change_state_handler(migration->vm_state);
unregister_savevm(VMSTATE_IF(vbasedev->dev), "vfio", vbasedev);
vfio_migration_exit(vbasedev);
+ vfio_unblock_multiple_devices_migration();
}
if (vbasedev->migration_blocker) {
--
2.26.3
- [PATCH v11 00/11] vfio/migration: Implement VFIO migration protocol v2, Avihai Horon, 2023/02/16
- [PATCH v11 02/11] vfio/migration: Fix NULL pointer dereference bug, Avihai Horon, 2023/02/16
- [PATCH v11 03/11] vfio/migration: Allow migration without VFIO IOMMU dirty tracking support, Avihai Horon, 2023/02/16
- [PATCH v11 01/11] linux-headers: Update to v6.2-rc8, Avihai Horon, 2023/02/16
- [PATCH v11 04/11] vfio/common: Change vfio_devices_all_running_and_saving() logic to equivalent one, Avihai Horon, 2023/02/16
- [PATCH v11 05/11] vfio/migration: Block multiple devices migration,
Avihai Horon <=
- [PATCH v11 06/11] vfio/migration: Move migration v1 logic to vfio_migration_init(), Avihai Horon, 2023/02/16
- [PATCH v11 07/11] vfio/migration: Rename functions/structs related to v1 protocol, Avihai Horon, 2023/02/16
- [PATCH v11 08/11] vfio/migration: Implement VFIO migration protocol v2, Avihai Horon, 2023/02/16
[PATCH v11 10/11] vfio: Alphabetize migration section of VFIO trace-events file, Avihai Horon, 2023/02/16