vfio: Split virqfd into a separate module for vfio bus drivers

An unintended consequence of commit 42ac9bd18d4f ("vfio: initialize
the virqfd workqueue in VFIO generic code") is that the vfio module
is renamed to vfio_core so that it can include both vfio and virqfd.
That's a user visible change that may break module loading scritps
and it imposes eventfd support as a dependency on the core vfio code,
which it's really not.  virqfd is intended to be provided as a service
to vfio bus drivers, so instead of wrapping it into vfio.ko, we can
make it a stand-alone module toggled by vfio bus drivers.  This has
the additional benefit of removing initialization and exit from the
core vfio code.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

1 files changed, 15 insertions, 2 deletions

diff --git a/drivers/vfio/virqfd.c b/drivers/vfio/virqfd.c
index 3d19aaf0e6c9..27c89cd5d70b 100644
--- a/drivers/vfio/virqfd.c
+++ b/drivers/vfio/virqfd.c
@@ -13,12 +13,17 @@
 #include <linux/vfio.h>
 #include <linux/eventfd.h>
 #include <linux/file.h>
+#include <linux/module.h>
 #include <linux/slab.h>
 
+#define DRIVER_VERSION  "0.1"
+#define DRIVER_AUTHOR   "Alex Williamson <alex.williamson@redhat.com>"
+#define DRIVER_DESC     "IRQFD support for VFIO bus drivers"
+
 static struct workqueue_struct *vfio_irqfd_cleanup_wq;
 static DEFINE_SPINLOCK(virqfd_lock);
 
-int __init vfio_virqfd_init(void)
+static int __init vfio_virqfd_init(void)
 {
 	vfio_irqfd_cleanup_wq =
 		create_singlethread_workqueue("vfio-irqfd-cleanup");
@@ -28,7 +33,7 @@ int __init vfio_virqfd_init(void)
 	return 0;
 }
 
-void vfio_virqfd_exit(void)
+static void __exit vfio_virqfd_exit(void)
 {
 	destroy_workqueue(vfio_irqfd_cleanup_wq);
 }
@@ -211,3 +216,11 @@ void vfio_virqfd_disable(struct virqfd **pvirqfd)
 	flush_workqueue(vfio_irqfd_cleanup_wq);
 }
 EXPORT_SYMBOL_GPL(vfio_virqfd_disable);
+
+module_init(vfio_virqfd_init);
+module_exit(vfio_virqfd_exit);
+
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);