[PATCH v3 02/11] virtio: pci: add PM notification handlers for restore, freeze, thaw, poweroff

Amit Shah
2011-11-17T12:00:55Z

Handle restore and freeze notification from the PM core. Expose these
to individual virtio drivers that can quiesce and resume vq operations.

These functions also save device-specific data so that the device can be
put in pre-suspend state after resume, and disable and enable the PCI
device in the freeze and resume functions, respectively.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
---
drivers/virtio/virtio_pci.c | 50 +++++++++++++++++++++++++++++++++++++++++++
include/linux/virtio.h | 4 +++
2 files changed, 54 insertions(+), 0 deletions(-)

diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c
index 5d36bc0..0db6f98 100644
--- a/drivers/virtio/virtio_pci.c
+++ b/drivers/virtio/virtio_pci.c
@@ -55,6 +55,10 @@ struct virtio_pci_device
unsigned msix_vectors;
/* 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;
};
@@ -708,9 +712,55 @@ static int virtio_pci_resume(struct device *dev)
return 0;
}

+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);
+
+ if (!ret)
+ pci_disable_device(pci_dev);
+ return ret;
+}
+
+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;
+ 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);
+ vp_set_status(&vp_dev->vdev, vp_dev->saved_status);
+ vp_finalize_features(&vp_dev->vdev);
+ if (drv && drv->restore)
+ ret = drv->restore(&vp_dev->vdev);
+
+ return ret;
+}
+
static const struct dev_pm_ops virtio_pci_pm_ops = {
.suspend = virtio_pci_suspend,
.resume = virtio_pci_resume,
+ .freeze = virtio_pci_freeze,
+ .thaw = virtio_pci_restore,
+ .restore = virtio_pci_restore,
+ .poweroff = virtio_pci_suspend,
};
#endif

diff --git a/include/linux/virtio.h b/include/linux/virtio.h
index 4c069d8..1c26416 100644
--- a/include/linux/virtio.h
+++ b/include/linux/virtio.h
@@ -146,6 +146,10 @@ struct virtio_driver {
int (*probe)(struct virtio_device *dev);
void (*remove)(struct virtio_device *dev);
void (*config_changed)(struct virtio_device *dev);
+#ifdef CONFIG_PM
+ int (*freeze)(struct virtio_device *dev);
+ int (*restore)(struct virtio_device *dev);
+#endif
};

int register_virtio_driver(struct virtio_driver *drv);
--
1.7.7.1