virtio-pci: move freeze/restore to virtio core

This is in preparation to extending config changed event handling
in core.
Wrapping these in an API also seems to make for a cleaner code.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

3 files changed, 62 insertions, 52 deletions

diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c
index 3980687401f6..8216b7311092 100644
--- a/drivers/virtio/virtio.c
+++ b/drivers/virtio/virtio.c
@@ -248,6 +248,60 @@ void virtio_config_changed(struct virtio_device *dev)
 }
 EXPORT_SYMBOL_GPL(virtio_config_changed);
 
+#ifdef CONFIG_PM_SLEEP
+int virtio_device_freeze(struct virtio_device *dev)
+{
+        struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);
+
+        dev->failed = dev->config->get_status(dev) & VIRTIO_CONFIG_S_FAILED;
+
+        if (drv && drv->freeze)
+                return drv->freeze(dev);
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_device_freeze);
+
+int virtio_device_restore(struct virtio_device *dev)
+{
+        struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);
+
+        /* We always start by resetting the device, in case a previous
+         * driver messed it up. */
+        dev->config->reset(dev);
+
+        /* Acknowledge that we've seen the device. */
+        add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE);
+
+        /* Maybe driver failed before freeze.
+         * Restore the failed status, for debugging. */
+        if (dev->failed)
+                add_status(dev, VIRTIO_CONFIG_S_FAILED);
+
+        if (!drv)
+                return 0;
+
+        /* We have a driver! */
+        add_status(dev, VIRTIO_CONFIG_S_DRIVER);
+
+        dev->config->finalize_features(dev);
+
+        if (drv->restore) {
+                int ret = drv->restore(dev);
+                if (ret) {
+                        add_status(dev, VIRTIO_CONFIG_S_FAILED);
+                        return ret;
+                }
+        }
+
+        /* Finally, tell the device we're all set */
+        add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK);
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_device_restore);
+#endif
+
 static int virtio_init(void)
 {
         if (bus_register(&virtio_bus) != 0)
diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c
index f39f4e772e6a..d34ebfa604f3 100644
--- a/drivers/virtio/virtio_pci.c
+++ b/drivers/virtio/virtio_pci.c
@@ -57,9 +57,6 @@ struct virtio_pci_device
         /* Vectors allocated, excluding per-vq vectors if any */
         unsigned msix_used_vectors;
 
-        /* Status saved during hibernate/restore */
-        u8 saved_status;
-
         /* Whether we have vector per vq */
         bool per_vq_vectors;
 };
@@ -764,16 +761,9 @@ static int virtio_pci_freeze(struct device *dev)
 {
         struct pci_dev *pci_dev = to_pci_dev(dev);
         struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
-        struct virtio_driver *drv;
         int ret;
 
-        drv = container_of(vp_dev->vdev.dev.driver,
-                           struct virtio_driver, driver);
-
-        ret = 0;
-        vp_dev->saved_status = vp_get_status(&vp_dev->vdev);
-        if (drv && drv->freeze)
-                ret = drv->freeze(&vp_dev->vdev);
+        ret = virtio_device_freeze(&vp_dev->vdev);
 
         if (!ret)
                 pci_disable_device(pci_dev);
@@ -784,54 +774,14 @@ static int virtio_pci_restore(struct device *dev)
 {
         struct pci_dev *pci_dev = to_pci_dev(dev);
         struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
-        struct virtio_driver *drv;
-        unsigned status = 0;
         int ret;
 
-        drv = container_of(vp_dev->vdev.dev.driver,
-                           struct virtio_driver, driver);
-
         ret = pci_enable_device(pci_dev);
         if (ret)
                 return ret;
 
         pci_set_master(pci_dev);
-        /* We always start by resetting the device, in case a previous
-         * driver messed it up. */
-        vp_reset(&vp_dev->vdev);
-
-        /* Acknowledge that we've seen the device. */
-        status |= VIRTIO_CONFIG_S_ACKNOWLEDGE;
-        vp_set_status(&vp_dev->vdev, status);
-
-        /* Maybe driver failed before freeze.
-         * Restore the failed status, for debugging. */
-        status |= vp_dev->saved_status & VIRTIO_CONFIG_S_FAILED;
-        vp_set_status(&vp_dev->vdev, status);
-
-        if (!drv)
-                return 0;
-
-        /* We have a driver! */
-        status |= VIRTIO_CONFIG_S_DRIVER;
-        vp_set_status(&vp_dev->vdev, status);
-
-        vp_finalize_features(&vp_dev->vdev);
-
-        if (drv->restore) {
-                ret = drv->restore(&vp_dev->vdev);
-                if (ret) {
-                        status |= VIRTIO_CONFIG_S_FAILED;
-                        vp_set_status(&vp_dev->vdev, status);
-                        return ret;
-                }
-        }
-
-        /* Finally, tell the device we're all set */
-        status |= VIRTIO_CONFIG_S_DRIVER_OK;
-        vp_set_status(&vp_dev->vdev, status);
-
-        return ret;
+        return virtio_device_restore(&vp_dev->vdev);
 }
 
 static const struct dev_pm_ops virtio_pci_pm_ops = {
diff --git a/include/linux/virtio.h b/include/linux/virtio.h
index 3c19bd3189cb..8df7ba81e5c7 100644
--- a/include/linux/virtio.h
+++ b/include/linux/virtio.h
@@ -78,6 +78,7 @@ bool virtqueue_is_broken(struct virtqueue *vq);
 /**
  * virtio_device - representation of a device using virtio
  * @index: unique position on the virtio bus
+ * @failed: saved value for CONFIG_S_FAILED bit (for restore)
  * @dev: underlying device.
  * @id: the device type identification (used to match it with a driver).
  * @config: the configuration ops for this device.
@@ -88,6 +89,7 @@ bool virtqueue_is_broken(struct virtqueue *vq);
  */
 struct virtio_device {
         int index;
+        bool failed;
         struct device dev;
         struct virtio_device_id id;
         const struct virtio_config_ops *config;
@@ -109,6 +111,10 @@ void unregister_virtio_device(struct virtio_device *dev);
 void virtio_break_device(struct virtio_device *dev);
 
 void virtio_config_changed(struct virtio_device *dev);
+#ifdef CONFIG_PM_SLEEP
+int virtio_device_freeze(struct virtio_device *dev);
+int virtio_device_restore(struct virtio_device *dev);
+#endif
 
 /**
  * virtio_driver - operations for a virtio I/O driver