virtio: fix module/device unloading

The virtio code never hooked through the ->remove callback.  Although
noone supports device removal at the moment, this code is already
needed for module unloading.

This of course also revealed bugs in virtio_blk, virtio_net and lguest
unloading paths.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

1 files changed, 13 insertions, 0 deletions

diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c
index 15d7787dea87..69d7ea02cd48 100644
--- a/drivers/virtio/virtio.c
+++ b/drivers/virtio/virtio.c
@@ -96,10 +96,23 @@ static int virtio_dev_probe(struct device *_d)
         return err;
 }
 
+static int virtio_dev_remove(struct device *_d)
+{
+        struct virtio_device *dev = container_of(_d,struct virtio_device,dev);
+        struct virtio_driver *drv = container_of(dev->dev.driver,
+                                                 struct virtio_driver, driver);
+
+        dev->config->set_status(dev, dev->config->get_status(dev)
+                                & ~VIRTIO_CONFIG_S_DRIVER);
+        drv->remove(dev);
+        return 0;
+}
+
 int register_virtio_driver(struct virtio_driver *driver)
 {
         driver->driver.bus = &virtio_bus;
         driver->driver.probe = virtio_dev_probe;
+        driver->driver.remove = virtio_dev_remove;
         return driver_register(&driver->driver);
 }
 EXPORT_SYMBOL_GPL(register_virtio_driver);