vfio-pci: Add device request interface
Userspace can opt to receive a device request notification,
indicating that the device should be released. This is setup
the same way as the error IRQ and also supports eventfd signaling.
Future support may forcefully remove the device from the user if
the request is ignored.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
index 7cc0122..f8a1863 100644
--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -239,9 +239,12 @@
return (flags & PCI_MSIX_FLAGS_QSIZE) + 1;
}
- } else if (irq_type == VFIO_PCI_ERR_IRQ_INDEX)
+ } else if (irq_type == VFIO_PCI_ERR_IRQ_INDEX) {
if (pci_is_pcie(vdev->pdev))
return 1;
+ } else if (irq_type == VFIO_PCI_REQ_IRQ_INDEX) {
+ return 1;
+ }
return 0;
}
@@ -464,6 +467,7 @@
switch (info.index) {
case VFIO_PCI_INTX_IRQ_INDEX ... VFIO_PCI_MSIX_IRQ_INDEX:
+ case VFIO_PCI_REQ_IRQ_INDEX:
break;
case VFIO_PCI_ERR_IRQ_INDEX:
if (pci_is_pcie(vdev->pdev))
@@ -828,6 +832,20 @@
req_len, vma->vm_page_prot);
}
+static void vfio_pci_request(void *device_data, unsigned int count)
+{
+ struct vfio_pci_device *vdev = device_data;
+
+ mutex_lock(&vdev->igate);
+
+ if (vdev->req_trigger) {
+ dev_dbg(&vdev->pdev->dev, "Requesting device from user\n");
+ eventfd_signal(vdev->req_trigger, 1);
+ }
+
+ mutex_unlock(&vdev->igate);
+}
+
static const struct vfio_device_ops vfio_pci_ops = {
.name = "vfio-pci",
.open = vfio_pci_open,
@@ -836,6 +854,7 @@
.read = vfio_pci_read,
.write = vfio_pci_write,
.mmap = vfio_pci_mmap,
+ .request = vfio_pci_request,
};
static int vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)