[RFC PATCH v1 2/2] vfio: Add VFIO API vfio_msi_get_irq

[Feng Wu <feng.wu@intel.com>]

This API returns the host irq for the MSI/MSI-X interrrupts.

Signed-off-by: Feng Wu <feng.wu@intel.com>
---
 drivers/vfio/pci/vfio_pci.c |   10 ++++++++++
 include/linux/vfio.h        |    2 ++
 2 files changed, 12 insertions(+), 0 deletions(-)

diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
index 9558da3..4fb9828 100644
--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -1009,6 +1009,16 @@ put_devs:
 	kfree(devs.devices);
 }
 
+unsigned int vfio_msi_get_irq(struct vfio_device *device, int vector, bool msix)
+{
+	struct vfio_pci_device *vdev =
+			(struct vfio_pci_device *)vfio_device_data(device);
+	struct pci_dev *pdev = vdev->pdev;
+
+	return msix ? vdev->msix[vector].vector : pdev->irq + vector;
+}
+EXPORT_SYMBOL_GPL(vfio_msi_get_irq);
+
 static void __exit vfio_pci_cleanup(void)
 {
 	pci_unregister_driver(&vfio_pci_driver);
diff --git a/include/linux/vfio.h b/include/linux/vfio.h
index d320411..007ca55 100644
--- a/include/linux/vfio.h
+++ b/include/linux/vfio.h
@@ -92,6 +92,8 @@ extern void vfio_unregister_iommu_driver(
 /*
  * External user API
  */
+extern unsigned int vfio_msi_get_irq(struct vfio_device *device, int vector,
+				      bool msix);
 extern struct vfio_group *vfio_group_get_external_user(struct file *filep);
 extern void vfio_group_put_external_user(struct vfio_group *group);
 extern int vfio_external_user_iommu_id(struct vfio_group *group);
-- 
1.7.1