From 050c588c2ef6edd75769e6c4869d0ad625d5be90 Mon Sep 17 00:00:00 2001
From: Kirti Wankhede <kwankhede@nvidia.com>
Date: Mon, 26 Oct 2020 15:06:16 +0530
Subject: [PATCH] vfio: Add migration state change notifier

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>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
---
 hw/vfio/migration.c           | 28 ++++++++++++++++++++++++++++
 hw/vfio/trace-events          |  1 +
 include/hw/vfio/vfio-common.h |  2 ++
 3 files changed, 31 insertions(+)

diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c
index e1ffae05e2..7ec85b6469 100644
--- a/hw/vfio/migration.c
+++ b/hw/vfio/migration.c
@@ -175,6 +175,30 @@ static void vfio_vmstate_change(void *opaque, int running, RunState state)
             (migration->device_state & mask) | value);
 }
 
+static void vfio_migration_state_notifier(Notifier *notifier, void *data)
+{
+    MigrationState *s = data;
+    VFIOMigration *migration = container_of(notifier, VFIOMigration,
+                                            migration_state);
+    VFIODevice *vbasedev = migration->vbasedev;
+    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 void vfio_migration_exit(VFIODevice *vbasedev)
 {
     VFIOMigration *migration = vbasedev->migration;
@@ -219,8 +243,11 @@ static int vfio_migration_init(VFIODevice *vbasedev,
     }
 
     migration = vbasedev->migration;
+    migration->vbasedev = vbasedev;
     migration->vm_state = qemu_add_vm_change_state_handler(vfio_vmstate_change,
                                                            vbasedev);
+    migration->migration_state.notify = vfio_migration_state_notifier;
+    add_migration_state_change_notifier(&migration->migration_state);
     return 0;
 
 err:
@@ -270,6 +297,7 @@ void vfio_migration_finalize(VFIODevice *vbasedev)
     if (vbasedev->migration) {
         VFIOMigration *migration = vbasedev->migration;
 
+        remove_migration_state_change_notifier(&migration->migration_state);
         qemu_del_vm_change_state_handler(migration->vm_state);
         vfio_migration_exit(vbasedev);
     }
diff --git a/hw/vfio/trace-events b/hw/vfio/trace-events
index 41de81f12f..78d7d83b5e 100644
--- a/hw/vfio/trace-events
+++ b/hw/vfio/trace-events
@@ -150,3 +150,4 @@ vfio_display_edid_write_error(void) ""
 vfio_migration_probe(const char *name, uint32_t index) " (%s) Region %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 9a571f1fb5..2bd593ba38 100644
--- a/include/hw/vfio/vfio-common.h
+++ b/include/hw/vfio/vfio-common.h
@@ -59,10 +59,12 @@ typedef struct VFIORegion {
 } VFIORegion;
 
 typedef struct VFIOMigration {
+    struct VFIODevice *vbasedev;
     VMChangeStateEntry *vm_state;
     VFIORegion region;
     uint32_t device_state;
     int vm_running;
+    Notifier migration_state;
 } VFIOMigration;
 
 typedef struct VFIOAddressSpace {