[PATCH v18 QEMU 07/18] vfio: Add migration state change notifier

[Kirti Wankhede <kwankhede@nvidia.com>]

Added migration state change notifier to get notification on migration state
change. These states are translated to VFIO device state and conveyed to vendor
driver.

Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Reviewed-by: Neo Jia <cjia@nvidia.com>
---
 hw/vfio/migration.c           | 30 ++++++++++++++++++++++++++++++
 hw/vfio/trace-events          |  5 +++--
 include/hw/vfio/vfio-common.h |  1 +
 3 files changed, 34 insertions(+), 2 deletions(-)

diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c
index e79b34003079..c2f5564b51c3 100644
--- a/hw/vfio/migration.c
+++ b/hw/vfio/migration.c
@@ -154,6 +154,28 @@ static void vfio_vmstate_change(void *opaque, int running, RunState state)
     }
 }
 
+static void vfio_migration_state_notifier(Notifier *notifier, void *data)
+{
+    MigrationState *s = data;
+    VFIODevice *vbasedev = container_of(notifier, VFIODevice, migration_state);
+    int ret;
+
+    trace_vfio_migration_state_notifier(vbasedev->name,
+                                        MigrationStatus_str(s->state));
+
+    switch (s->state) {
+    case MIGRATION_STATUS_CANCELLING:
+    case MIGRATION_STATUS_CANCELLED:
+    case MIGRATION_STATUS_FAILED:
+        ret = vfio_migration_set_state(vbasedev,
+                      ~(VFIO_DEVICE_STATE_SAVING | VFIO_DEVICE_STATE_RESUMING),
+                      VFIO_DEVICE_STATE_RUNNING);
+        if (ret) {
+            error_report("%s: Failed to set state RUNNING", vbasedev->name);
+        }
+    }
+}
+
 static int vfio_migration_init(VFIODevice *vbasedev,
                                struct vfio_region_info *info)
 {
@@ -173,6 +195,9 @@ static int vfio_migration_init(VFIODevice *vbasedev,
     vbasedev->vm_state = qemu_add_vm_change_state_handler(vfio_vmstate_change,
                                                           vbasedev);
 
+    vbasedev->migration_state.notify = vfio_migration_state_notifier;
+    add_migration_state_change_notifier(&vbasedev->migration_state);
+
     return 0;
 }
 
@@ -211,6 +236,11 @@ add_blocker:
 
 void vfio_migration_finalize(VFIODevice *vbasedev)
 {
+
+    if (vbasedev->migration_state.notify) {
+        remove_migration_state_change_notifier(&vbasedev->migration_state);
+    }
+
     if (vbasedev->vm_state) {
         qemu_del_vm_change_state_handler(vbasedev->vm_state);
     }
diff --git a/hw/vfio/trace-events b/hw/vfio/trace-events
index 14b0a86c0035..bd3d47b005cb 100644
--- a/hw/vfio/trace-events
+++ b/hw/vfio/trace-events
@@ -146,5 +146,6 @@ vfio_display_edid_write_error(void) ""
 
 # migration.c
 vfio_migration_probe(const char *name, uint32_t index) " (%s) Region %d"
-vfio_migration_set_state(char *name, uint32_t state) " (%s) state %d"
-vfio_vmstate_change(char *name, int running, const char *reason, uint32_t dev_state) " (%s) running %d reason %s device state %d"
+vfio_migration_set_state(const char *name, uint32_t state) " (%s) state %d"
+vfio_vmstate_change(const char *name, int running, const char *reason, uint32_t dev_state) " (%s) running %d reason %s device state %d"
+vfio_migration_state_notifier(const char *name, const char *state) " (%s) state %s"
diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
index 3d18eb146b33..28f55f66d019 100644
--- a/include/hw/vfio/vfio-common.h
+++ b/include/hw/vfio/vfio-common.h
@@ -123,6 +123,7 @@ typedef struct VFIODevice {
     VMChangeStateEntry *vm_state;
     uint32_t device_state;
     int vm_running;
+    Notifier migration_state;
 } VFIODevice;
 
 struct VFIODeviceOps {
-- 
2.7.0