Because we have potentially-infinite feature bits, it's hard for the device
to know when features are finalized.
This adds a new status bit, VIRTIO_CONFIG_S_FEATURES_DONE, which is only
set by the modern virtio_pci driver at the moment.
Signed-off-by: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
---
drivers/virtio/virtio_pci-common.c | 28 --------------
drivers/virtio/virtio_pci-common.h | 1 -
drivers/virtio/virtio_pci.c | 73 ++++++++++++++++++++++++++----------
drivers/virtio/virtio_pci_legacy.c | 27 +++++++++++++
include/uapi/linux/virtio_config.h | 2 +
5 files changed, 83 insertions(+), 48 deletions(-)
diff --git a/drivers/virtio/virtio_pci-common.c b/drivers/virtio/virtio_pci-common.c
index d4e33ad..d2c78c8 100644
--- a/drivers/virtio/virtio_pci-common.c
+++ b/drivers/virtio/virtio_pci-common.c
@@ -392,32 +392,4 @@ int virtio_pci_freeze(struct device *dev)
pci_disable_device(pci_dev);
return ret;
}
-
-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_dev->vdev.config->finalize_features(&vp_dev->vdev);
-
- if (drv && drv->restore)
- ret = drv->restore(&vp_dev->vdev);
-
- /* Finally, tell the device we're all set */
- if (!ret)
- vp_dev->vdev.config->set_status(&vp_dev->vdev,
- vp_dev->saved_status);
-
- return ret;
-}
#endif
diff --git a/drivers/virtio/virtio_pci-common.h b/drivers/virtio/virtio_pci-common.h
index 146c3be..dac434e 100644
--- a/drivers/virtio/virtio_pci-common.h
+++ b/drivers/virtio/virtio_pci-common.h
@@ -118,5 +118,4 @@ int virtio_pci_set_vq_affinity(struct virtqueue *vq, int cpu);
#ifdef CONFIG_PM
int virtio_pci_freeze(struct device *dev);
-int virtio_pci_restore(struct device *dev);
#endif
diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c
index 97d9b54..4614a15 100644
--- a/drivers/virtio/virtio_pci.c
+++ b/drivers/virtio/virtio_pci.c
@@ -50,6 +50,21 @@ static u64 ioread64(__le64 *addr)
return ioread32(addr) | ((u64)ioread32((__le32 *)addr + 1) << 32);
}
+/* config->{get,set}_status() implementations */
+static u8 vp_get_status(struct virtio_device *vdev)
+{
+ struct virtio_pci_device *vp_dev = to_vp_device(vdev);
+ return ioread8(&vp_dev->common->device_status);
+}
+
+static void vp_set_status(struct virtio_device *vdev, u8 status)
+{
+ struct virtio_pci_device *vp_dev = to_vp_device(vdev);
+ /* We should never be setting status to 0. */
+ BUG_ON(status == 0);
+ iowrite8(status, &vp_dev->common->device_status);
+}
+
static u64 vp_get_features(struct virtio_device *vdev)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
@@ -62,19 +77,27 @@ static u64 vp_get_features(struct virtio_device *vdev)
return features;
}
-static void vp_finalize_features(struct virtio_device *vdev)
+static void write_features(struct virtio_device *vdev)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
- /* Give virtio_ring a chance to accept features. */
- vring_transport_features(vdev);
-
iowrite32(0, &vp_dev->common->guest_feature_select);
iowrite32((u32)vdev->features, &vp_dev->common->guest_feature);
iowrite32(1, &vp_dev->common->guest_feature_select);
iowrite32(vdev->features >> 32, &vp_dev->common->guest_feature);
}
+static void vp_finalize_features(struct virtio_device *vdev)
+{
+ /* Give virtio_ring a chance to accept features. */
+ vring_transport_features(vdev);
+
+ write_features(vdev);
+
+ /* Update status to lock it in. */
+ vp_set_status(vdev, vp_get_status(vdev)|VIRTIO_CONFIG_S_FEATURES_DONE);
+}
+
/* virtio config is little-endian for virtio_pci (vs guest-endian for legacy) */
static u8 vp_get8(struct virtio_device *vdev, unsigned offset)
{
@@ -132,21 +155,6 @@ static void vp_set64(struct virtio_device *vdev, unsigned offset, u64 val)
iowrite64(val, vp_dev->device + offset);
}
-/* config->{get,set}_status() implementations */
-static u8 vp_get_status(struct virtio_device *vdev)
-{
- struct virtio_pci_device *vp_dev = to_vp_device(vdev);
- return ioread8(&vp_dev->common->device_status);
-}
-
-static void vp_set_status(struct virtio_device *vdev, u8 status)
-{
- struct virtio_pci_device *vp_dev = to_vp_device(vdev);
- /* We should never be setting status to 0. */
- BUG_ON(status == 0);
- iowrite8(status, &vp_dev->common->device_status);
-}
-
static void vp_reset(struct virtio_device *vdev)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
@@ -571,6 +579,33 @@ static void virtio_pci_remove(struct pci_dev *pci_dev)
}
#ifdef CONFIG_PM
+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);
+ write_features(&vp_dev->vdev);
+
+ if (drv && drv->restore)
+ ret = drv->restore(&vp_dev->vdev);
+
+ /* Finally, tell the device we're all set */
+ if (!ret)
+ vp_set_status(&vp_dev->vdev, vp_dev->saved_status);
+
+ return ret;
+}
+
static const struct dev_pm_ops virtio_pci_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(virtio_pci_freeze, virtio_pci_restore)
};
diff --git a/drivers/virtio/virtio_pci_legacy.c b/drivers/virtio/virtio_pci_legacy.c
index f78a858..cfff009 100644
--- a/drivers/virtio/virtio_pci_legacy.c
+++ b/drivers/virtio/virtio_pci_legacy.c
@@ -436,6 +436,33 @@ static void virtio_pci_remove(struct pci_dev *pci_dev)
}
#ifdef CONFIG_PM
+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_finalize_features(&vp_dev->vdev);
+
+ if (drv && drv->restore)
+ ret = drv->restore(&vp_dev->vdev);
+
+ /* Finally, tell the device we're all set */
+ if (!ret)
+ vp_set_status(&vp_dev->vdev, vp_dev->saved_status);
+
+ return ret;
+}
+
static const struct dev_pm_ops virtio_pci_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(virtio_pci_freeze, virtio_pci_restore)
};
diff --git a/include/uapi/linux/virtio_config.h b/include/uapi/linux/virtio_config.h
index b7cda39..83848b7 100644
--- a/include/uapi/linux/virtio_config.h
+++ b/include/uapi/linux/virtio_config.h
@@ -36,6 +36,8 @@
#define VIRTIO_CONFIG_S_ACKNOWLEDGE 1
/* We have found a driver for the device. */
#define VIRTIO_CONFIG_S_DRIVER 2
+/* Features are finalized (only for new virtio_pci) */
+#define VIRTIO_CONFIG_S_FEATURES_DONE 8
/* Driver has used its parts of the config, and is happy */
#define VIRTIO_CONFIG_S_DRIVER_OK 4
/* We've given up on this device. */
--
1.7.10.4
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