From: Dominik Behr <dbehr@xxxxxxxxxxxx>
Hitherto there was no support for propagating ACPI notifications to the
guest drivers. In order to provide such support, install a handler for
notifications on an ACPI device during vfio-pci device registration. The
handler role is to propagate such ACPI notifications to the user-space
via acpi netlink events, which allows VMM to receive and propagate them
further to the VMs.
Thanks to the above, the actual driver for the pass-through device,
which belongs to the guest, can receive and react to device specific
notifications.
Signed-off-by: Dominik Behr <dbehr@xxxxxxxxxxxx>
Co-developed-by: Grzegorz Jaszczyk <jaz@xxxxxxxxxxxx>
Signed-off-by: Grzegorz Jaszczyk <jaz@xxxxxxxxxxxx>
---
drivers/vfio/pci/vfio_pci_core.c | 33 ++++++++++++++++++++++++++++++++
1 file changed, 33 insertions(+)
diff --git a/drivers/vfio/pci/vfio_pci_core.c b/drivers/vfio/pci/vfio_pci_core.c
index a5ab416cf476..92b8ed8d087c 100644
--- a/drivers/vfio/pci/vfio_pci_core.c
+++ b/drivers/vfio/pci/vfio_pci_core.c
@@ -10,6 +10,7 @@
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+#include <linux/acpi.h>
#include <linux/aperture.h>
#include <linux/device.h>
#include <linux/eventfd.h>
@@ -2120,10 +2121,20 @@ void vfio_pci_core_release_dev(struct vfio_device *core_vdev)
}
EXPORT_SYMBOL_GPL(vfio_pci_core_release_dev);
+static void vfio_pci_core_acpi_notify(acpi_handle handle, u32 event, void *data)
+{
+ struct vfio_pci_core_device *vdev = (struct vfio_pci_core_device *)data;
+ struct device *dev = &vdev->pdev->dev;
+
+ acpi_bus_generate_netlink_event("vfio_pci", dev_name(dev), event, 0);
+}
+
int vfio_pci_core_register_device(struct vfio_pci_core_device *vdev)
{
+ acpi_status status;
struct pci_dev *pdev = vdev->pdev;
struct device *dev = &pdev->dev;
+ struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
int ret;
/* Drivers must set the vfio_pci_core_device to their drvdata */
@@ -2201,8 +2212,24 @@ int vfio_pci_core_register_device(struct vfio_pci_core_device *vdev)
ret = vfio_register_group_dev(&vdev->vdev);
if (ret)
goto out_power;
+
+ if (!adev) {
+ pci_info(pdev, "No ACPI companion");
+ return 0;
+ }
+
+ status = acpi_install_notify_handler(adev->handle, ACPI_DEVICE_NOTIFY,
+ vfio_pci_core_acpi_notify, (void *)vdev);
+
+ if (ACPI_FAILURE(status)) {
+ pci_err(pdev, "Failed to install notify handler");
+ goto out_group_register;
+ }
+
return 0;
+out_group_register:
+ vfio_unregister_group_dev(&vdev->vdev);
out_power:
if (!disable_idle_d3)
pm_runtime_get_noresume(dev);
@@ -2216,6 +2243,12 @@ EXPORT_SYMBOL_GPL(vfio_pci_core_register_device);
void vfio_pci_core_unregister_device(struct vfio_pci_core_device *vdev)
{
+ struct acpi_device *adev = ACPI_COMPANION(&vdev->pdev->dev);
+
+ if (adev)
+ acpi_remove_notify_handler(adev->handle, ACPI_DEVICE_NOTIFY,
+ vfio_pci_core_acpi_notify);
+
vfio_pci_core_sriov_configure(vdev, 0);
vfio_unregister_group_dev(&vdev->vdev);
--
2.40.0.rc0.216.gc4246ad0f0-goog
