[libvirt] [PATCH v4 04/10] Wait for vfio-pci device cleanups before reassinging the device to host driver

[Shivaprasad G Bhat]

Before unbind from stub driver libvirt should be sure the guest is not using
the device anymore. The libvirt today waits for pci-stub driver alone in /proc/iommu.
The same wait is needed for vfio devices too.

Signed-off-by: Shivaprasad G Bhat <sbhat at linux.vnet.ibm.com>
---
 src/util/virhostdev.c |    7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/util/virhostdev.c b/src/util/virhostdev.c
index f24ccd8..9f15f34 100644
--- a/src/util/virhostdev.c
+++ b/src/util/virhostdev.c
@@ -756,6 +756,13 @@ virHostdevReattachPCIDevice(virPCIDevicePtr dev, virHostdevManagerPtr mgr)
             usleep(100*1000);
             retries--;
         }
+    } else if (STREQ(virPCIDeviceGetStubDriver(dev), "vfio-pci")) {
+        int retries = 100;
+        while (virPCIDeviceWaitForCleanup(dev, "vfio-pci")
+               && retries) {
+            usleep(100*1000);
+            retries--;
+        }
     }
 
     if (virPCIDeviceReattach(dev, mgr->activePCIHostdevs,