Reworked power and plug and play

CMakeLists.txt

@@ -18,7 +18,7 @@ string(REPLACE "/RTC1" "" CMAKE_C_FLAGS_DEBUG "${CMAKE_C_FLAGS_DEBUG}")
 set(SOURCES
     chief/driver.cpp
     chief/major_functions.cpp
-    chief/spinlock.cpp
+    chief/pipe.cpp
     chief/usb.cpp
 )
 

chief/device_extension.hpp

@@ -8,11 +8,24 @@ extern "C" {
 
 #include "maybe.hpp"
 
+/**
+ * @brief Payload we are receiving/sending from the 
+ * application in a mj device control
+ * 
+ */
 struct usb_chief_vendor_request {
-    unsigned short Request;
+    // usb request fields. Is sometimes used as input 
+    // and as output
+    unsigned short request;
+
+    // usb specific fields
     unsigned short value;
     unsigned short index;
+
+    // length of the data buffer
     unsigned short length;
+
+    // pointer to the data buffer
     void *data;
 };
 
@@ -21,29 +34,61 @@ struct usb_chief_vendor_request {
  * 
  */
 struct chief_device_extension {
-  PDEVICE_OBJECT attachedDeviceObject;
-  PDEVICE_OBJECT physicalDeviceObject;
-  POWER_STATE current_power_state;
-  PUSB_CONFIGURATION_DESCRIPTOR usb_config_desc;
-  PUSBD_INTERFACE_INFORMATION usb_interface_info;
-  DEVICE_CAPABILITIES device_capabilities;
-  IRP *power_irp;
-  KEVENT pipe_count_empty;
-  KEVENT event1;
-  KEVENT event2;
-  KEVENT power_complete_event;
-  KSPIN_LOCK device_lock;
-  LONG InterlockedValue1;
-  LONG pipe_open_count;
-  bool *allocated_pipes;
-  volatile bool is_ejecting;
-  volatile bool is_removing;
-  volatile bool is_stopped;
-  volatile bool wait_wake_in_progress;
-  volatile bool power_request_busy;
-  POWER_STATE target_power_state;
-
-  // The BCD version of the connected USB device
-  maybe<unsigned short> bcdUSB;
+    // the device objects we are connected to
+    PDEVICE_OBJECT attachedDeviceObject;
+    PDEVICE_OBJECT physicalDeviceObject;
+
+    // the current power state of the device
+    POWER_STATE current_power_state;
+
+    // the current usb configuration descriptor
+    PUSB_CONFIGURATION_DESCRIPTOR usb_config_desc;
+
+    // the current usb interface information
+    PUSBD_INTERFACE_INFORMATION usb_interface_info;
+
+    // the device capabilities structure. This is used
+    // to know what power state we need to go to for each
+    // system power state
+    DEVICE_CAPABILITIES device_capabilities;
+
+    // event to signal when the pipe count is zero. This
+    // can only happen when all opened pipes are closed
+    // and IRP_MN_REMOVE_DEVICE is called
+    KEVENT pipe_count_empty;
+
+    // spinlock to protect the active_pipe_count
+    KSPIN_LOCK device_lock;
+
+    // count of opened pipes
+    LONG active_pipe_count;
+
+    // an array with flags for each pipe if it is opened 
+    // or not
+    bool *allocated_pipes;
+
+    // flag if the device has been removed. This means
+    // that we cannot accept new ioctls/reads/writes.
+    // When this flag is set we cannot talk to the device 
+    // anymore
+    volatile bool device_removed;
+
+    // flag if the device is remove pending. This means
+    // that we should not accept new ioctls/reads/writes
+    // and that the device should be considered as being 
+    // removed until it is deleted or canceled
+    volatile bool remove_pending;
+
+    // flag if new requests should be held. This is used during
+    // stop device to prevent new ioctls/reads/writes from
+    // being processed until the device is started again
+    volatile bool hold_new_requests;
+
+    // The BCD version of the connected USB device
+    maybe<unsigned short> bcdUSB;
+
+    // count of active power irps. Should only be modified 
+    // using Interlocked functions
+    LONG power_irp_count;
 };
 

chief/driver.cpp

@@ -3,7 +3,7 @@
 #include "driver.hpp"
 #include "major_functions.hpp"
 #include "device_extension.hpp"
-#include "spinlock.hpp"
+#include "pipe.hpp"
 
 /**
  * @brief Unload routine for the driver.
@@ -66,9 +66,6 @@ NTSTATUS add_chief_device(PDRIVER_OBJECT driver_object, PDEVICE_OBJECT& device_o
 
     // initalize the events
     KeInitializeEvent(&dev_ext->pipe_count_empty, NotificationEvent, FALSE);
-    KeInitializeEvent(&dev_ext->event1, NotificationEvent, FALSE);
-    KeInitializeEvent(&dev_ext->event2, NotificationEvent, FALSE);
-    KeInitializeEvent(&dev_ext->power_complete_event, NotificationEvent, FALSE);
 
     // initialize spinlocks
     KeInitializeSpinLock(&dev_ext->device_lock);
@@ -177,15 +174,14 @@ static NTSTATUS add_device(__in struct _DRIVER_OBJECT *DriverObject, __in struct
     dev_ext->device_capabilities.Version = 1;
     dev_ext->device_capabilities.Address = static_cast<ULONG>(-1);
     dev_ext->device_capabilities.UINumber = static_cast<ULONG>(-1);
+    dev_ext->device_capabilities.DeviceWake = PowerDeviceUnspecified;
 
     // start the device
     io_call_start_device(dev_ext->attachedDeviceObject, &dev_ext->device_capabilities);
 
-    // set the current power state to unspecified
-    dev_ext->target_power_state.DeviceState = PowerDeviceUnspecified;
-
-    // acquire the spinlock
-    spinlock_increment(device_object);
+    // increment the pipe count for the first time so we 
+    // never reach zero except when the device is removed
+    increment_active_pipe_count(device_object);
 
     // clear the flag we are inititializing
     device_object->Flags &= ~DO_DEVICE_INITIALIZING;