[PATCH v4 03/25] virtio-pci: move freeze/restore to virtio core

Michael S. Tsirkin
2014-10-13T07:48:27Z

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>
---
include/linux/virtio.h | 6 +++++
drivers/virtio/virtio.c | 54 +++++++++++++++++++++++++++++++++++++++++++++
drivers/virtio/virtio_pci.c | 54 ++-------------------------------------------
3 files changed, 62 insertions(+), 52 deletions(-)

diff --git a/include/linux/virtio.h b/include/linux/virtio.h
index 3c19bd3..8df7ba8 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
diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c
index 3980687..8216b73 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 f39f4e7..d34ebfa 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 = {
--
MST