[bus] Track if the bus module has been initialized

Since bus__add_child() is a library function, we don't really
want a caller using it unless the WinVBlock driver is
actually running.  We now track module initialization status.

diff --git a/src/include/bus.h b/src/include/bus.h
index acdad4f..3a5f5fd 100644 (file)
--- a/src/include/bus.h
+++ b/src/include/bus.h
@@ -49,30 +49,10 @@ extern NTSTATUS STDCALL bus__get_dev_capabilities(
 
 extern NTSTATUS bus__module_init(void);
 extern void bus__module_shutdown(void);
-
-/**
- * Create a new bus.
- *
- * @ret bus_ptr         The address of a new bus, or NULL for failure.
- *
- * This function should not be confused with a PDO creation routine, which is
- * actually implemented for each device type.  This routine will allocate a
- * bus__type, track it in a global list, as well as populate the bus
- * with default values.
- */
 extern winvblock__lib_func struct bus__type * bus__create(void);
-
-/**
- * Add a child node to the bus.
- *
- * @v bus_ptr           Points to the bus receiving the child.
- * @v dev_ptr           Points to the child device to add.
- *
- * Returns TRUE for success, FALSE for failure.
- */
 extern winvblock__lib_func winvblock__bool STDCALL bus__add_child(
-    IN OUT struct bus__type * bus_ptr,
-    IN device__type_ptr dev_ptr
+    IN OUT struct bus__type *,
+    IN device__type_ptr
   );
 
 /**

diff --git a/src/winvblock/bus/bus.c b/src/winvblock/bus/bus.c
index 503b309..13f186e 100644 (file)
--- a/src/winvblock/bus/bus.c
+++ b/src/winvblock/bus/bus.c
@@ -42,6 +42,7 @@
 static PDEVICE_OBJECT bus__boot_fdo_ = NULL;
 static LIST_ENTRY bus__list_;
 static KSPIN_LOCK bus__list_lock_;
+winvblock__bool bus__module_up_ = FALSE;
 
 /* Forward declarations. */
 static device__free_func bus__free_;
@@ -60,7 +61,9 @@ void bus__module_shutdown(void) {
       );
     IoDeleteSymbolicLink(&DosDeviceName);
     bus__boot_fdo_ = NULL;
+    bus__module_up_ = FALSE;
     DBG("Exit\n");
+    return;
   }
 
 /**
@@ -74,14 +77,16 @@ winvblock__lib_func winvblock__bool STDCALL bus__add_child(
     IN OUT struct bus__type * bus_ptr,
     IN OUT device__type_ptr dev_ptr
   ) {
-    /**
-     * @v dev_obj_ptr         The new node's device object.
-     * @v walker              Walks the child nodes.
-     */
+    /* The new node's device object. */
     PDEVICE_OBJECT dev_obj_ptr;
+    /* Walks the child nodes. */
     device__type_ptr walker;
   
     DBG("Entry\n");
+    if (!bus__module_up_) {
+        DBG("Bus module not initialized.\n");
+        return FALSE;
+      }
     if ((bus_ptr == NULL) || (dev_ptr == NULL)) {
         DBG("No bus or no device!\n");
         return FALSE;
@@ -352,7 +357,10 @@ static NTSTATUS STDCALL bus_dispatch(
  *
  * @ret bus_ptr         The address of a new bus, or NULL for failure.
  *
- * See the header file for additional details.
+ * This function should not be confused with a PDO creation routine, which is
+ * actually implemented for each device type.  This routine will allocate a
+ * bus__type, track it in a global list, as well as populate the bus
+ * with default values.
  */
 winvblock__lib_func struct bus__type * bus__create(void) {
     device__type_ptr dev_ptr;
@@ -481,6 +489,7 @@ NTSTATUS bus__module_init(void) {
       }
     bus__boot_fdo_ = boot_bus_ptr->device->Self;
 
+    bus__module_up_ = TRUE;
     return STATUS_SUCCESS;
   }