Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio updates from Michael Tsirkin:
 "Several new features here:

   - virtio-net is finally supported in vduse

   - virtio (balloon and mem) interaction with suspend is improved

   - vhost-scsi now handles signals better/faster

  And fixes, cleanups all over the place"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (48 commits)
  virtio-pci: Check if is_avq is NULL
  virtio: delete vq in vp_find_vqs_msix() when request_irq() fails
  MAINTAINERS: add Eugenio Pérez as reviewer
  vhost-vdpa: Remove usage of the deprecated ida_simple_xx() API
  vp_vdpa: don't allocate unused msix vectors
  sound: virtio: drop owner assignment
  fuse: virtio: drop owner assignment
  scsi: virtio: drop owner assignment
  rpmsg: virtio: drop owner assignment
  nvdimm: virtio_pmem: drop owner assignment
  wifi: mac80211_hwsim: drop owner assignment
  vsock/virtio: drop owner assignment
  net: 9p: virtio: drop owner assignment
  net: virtio: drop owner assignment
  net: caif: virtio: drop owner assignment
  misc: nsm: drop owner assignment
  iommu: virtio: drop owner assignment
  drm/virtio: drop owner assignment
  gpio: virtio: drop owner assignment
  firmware: arm_scmi: virtio: drop owner assignment
  ...

1 files changed, 62 insertions, 7 deletions

diff --git a/drivers/virtio/virtio_mem.c b/drivers/virtio/virtio_mem.c
index e8355f55a8f7..a3857bacc844 100644
--- a/drivers/virtio/virtio_mem.c
+++ b/drivers/virtio/virtio_mem.c
@@ -22,6 +22,7 @@
 #include <linux/lockdep.h>
 #include <linux/log2.h>
 #include <linux/vmalloc.h>
+#include <linux/suspend.h>
 
 #include <acpi/acpi_numa.h>
 
@@ -253,6 +254,9 @@ struct virtio_mem {
 	/* Memory notifier (online/offline events). */
 	struct notifier_block memory_notifier;
 
+	/* Notifier to block hibernation image storing/reloading. */
+	struct notifier_block pm_notifier;
+
 #ifdef CONFIG_PROC_VMCORE
 	/* vmcore callback for /proc/vmcore handling in kdump mode */
 	struct vmcore_cb vmcore_cb;
@@ -1112,6 +1116,25 @@ static int virtio_mem_memory_notifier_cb(struct notifier_block *nb,
 	return rc;
 }
 
+static int virtio_mem_pm_notifier_cb(struct notifier_block *nb,
+				     unsigned long action, void *arg)
+{
+	struct virtio_mem *vm = container_of(nb, struct virtio_mem,
+					     pm_notifier);
+	switch (action) {
+	case PM_HIBERNATION_PREPARE:
+	case PM_RESTORE_PREPARE:
+		/*
+		 * When restarting the VM, all memory is unplugged. Don't
+		 * allow to hibernate and restore from an image.
+		 */
+		dev_err(&vm->vdev->dev, "hibernation is not supported.\n");
+		return NOTIFY_BAD;
+	default:
+		return NOTIFY_OK;
+	}
+}
+
 /*
  * Set a range of pages PG_offline. Remember pages that were never onlined
  * (via generic_online_page()) using PageDirty().
@@ -2616,11 +2639,19 @@ static int virtio_mem_init_hotplug(struct virtio_mem *vm)
 	rc = register_memory_notifier(&vm->memory_notifier);
 	if (rc)
 		goto out_unreg_group;
-	rc = register_virtio_mem_device(vm);
+	/* Block hibernation as early as possible. */
+	vm->pm_notifier.priority = INT_MAX;
+	vm->pm_notifier.notifier_call = virtio_mem_pm_notifier_cb;
+	rc = register_pm_notifier(&vm->pm_notifier);
 	if (rc)
 		goto out_unreg_mem;
+	rc = register_virtio_mem_device(vm);
+	if (rc)
+		goto out_unreg_pm;
 
 	return 0;
+out_unreg_pm:
+	unregister_pm_notifier(&vm->pm_notifier);
 out_unreg_mem:
 	unregister_memory_notifier(&vm->memory_notifier);
 out_unreg_group:
@@ -2898,6 +2929,7 @@ static void virtio_mem_deinit_hotplug(struct virtio_mem *vm)
 
 	/* unregister callbacks */
 	unregister_virtio_mem_device(vm);
+	unregister_pm_notifier(&vm->pm_notifier);
 	unregister_memory_notifier(&vm->memory_notifier);
 
 	/*
@@ -2961,17 +2993,40 @@ static void virtio_mem_config_changed(struct virtio_device *vdev)
 #ifdef CONFIG_PM_SLEEP
 static int virtio_mem_freeze(struct virtio_device *vdev)
 {
+	struct virtio_mem *vm = vdev->priv;
+
 	/*
-	 * When restarting the VM, all memory is usually unplugged. Don't
-	 * allow to suspend/hibernate.
+	 * We block hibernation using the PM notifier completely. The workqueue
+	 * is already frozen by the PM core at this point, so we simply
+	 * reset the device and cleanup the queues.
 	 */
-	dev_err(&vdev->dev, "save/restore not supported.\n");
-	return -EPERM;
+	if (pm_suspend_target_state != PM_SUSPEND_TO_IDLE &&
+	    vm->plugged_size &&
+	    !virtio_has_feature(vm->vdev, VIRTIO_MEM_F_PERSISTENT_SUSPEND)) {
+		dev_err(&vm->vdev->dev,
+			"suspending with plugged memory is not supported\n");
+		return -EPERM;
+	}
+
+	virtio_reset_device(vdev);
+	vdev->config->del_vqs(vdev);
+	vm->vq = NULL;
+	return 0;
 }
 
 static int virtio_mem_restore(struct virtio_device *vdev)
 {
-	return -EPERM;
+	struct virtio_mem *vm = vdev->priv;
+	int ret;
+
+	ret = virtio_mem_init_vq(vm);
+	if (ret)
+		return ret;
+	virtio_device_ready(vdev);
+
+	/* Let's check if anything changed. */
+	virtio_mem_config_changed(vdev);
+	return 0;
 }
 #endif
 
@@ -2980,6 +3035,7 @@ static unsigned int virtio_mem_features[] = {
 	VIRTIO_MEM_F_ACPI_PXM,
 #endif
 	VIRTIO_MEM_F_UNPLUGGED_INACCESSIBLE,
+	VIRTIO_MEM_F_PERSISTENT_SUSPEND,
 };
 
 static const struct virtio_device_id virtio_mem_id_table[] = {
@@ -2991,7 +3047,6 @@ static struct virtio_driver virtio_mem_driver = {
 	.feature_table = virtio_mem_features,
 	.feature_table_size = ARRAY_SIZE(virtio_mem_features),
 	.driver.name = KBUILD_MODNAME,
-	.driver.owner = THIS_MODULE,
 	.id_table = virtio_mem_id_table,
 	.probe = virtio_mem_probe,
 	.remove = virtio_mem_remove,