usb: add usb_bus_release function

add global variables releasing logic when the usb buses
were removed or hot-unpluged.

Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/hw/usb/bus.c b/hw/usb/bus.c
index 516fb52993..c7c4dadedd 100644
--- a/hw/usb/bus.c
+++ b/hw/usb/bus.c
@@ -87,6 +87,13 @@ void usb_bus_new(USBBus *bus, size_t bus_size,
     QTAILQ_INSERT_TAIL(&busses, bus, next);
 }
 
+void usb_bus_release(USBBus *bus)
+{
+    assert(next_usb_bus > 0);
+
+    QTAILQ_REMOVE(&busses, bus, next);
+}
+
 USBBus *usb_bus_find(int busnr)
 {
     USBBus *bus;