We need to guarantee that when cancel returns that the callback won't be called

anymore. It could happen that the transfer was already in the process of being
finished, so wasn't in the list of pending transfers anymore. Cancel would then
return even though the callback wasn't called yet. This could lead to a callback
being called after a driver was already unloaded (even after it cleaned up the
pipes it used).


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@33239 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/add-ons/kernel/busses/usb/ehci.cpp

@@ -119,6 +119,7 @@ EHCI::EHCI(pci_info *info, Stack *stack)
 		fCleanupThread(-1),
 		fStopThreads(false),
 		fFreeListHead(NULL),
+		fProcessingPipe(NULL),
 		fRootHub(NULL),
 		fRootHubAddress(0),
 		fPortCount(0),
@@ -941,6 +942,10 @@ EHCI::CancelQueuedTransfers(Pipe *pipe, bool force)
 		list = next;
 	}
 
+	// wait for any transfers that might have made it before canceling
+	while (fProcessingPipe == pipe)
+		snooze(1000);
+
 	// notify the finisher so it can clean up the canceled transfers
 	release_sem_etc(fFinishTransfersSem, 1, B_DO_NOT_RESCHEDULE);
 	return B_OK;
@@ -1075,6 +1080,11 @@ EHCI::FinishTransfers()
 				if (transfer == fLastTransfer)
 					fLastTransfer = lastTransfer;
 
+				// store the currently processing pipe here so we can wait
+				// in cancel if we are processing something on the target pipe
+				if (!transfer->canceled)
+					fProcessingPipe = transfer->transfer->TransferPipe();
+
 				transfer->link = NULL;
 				Unlock();
 			}
@@ -1135,6 +1145,7 @@ EHCI::FinishTransfers()
 				}
 
 				transfer->transfer->Finished(callbackStatus, actualLength);
+				fProcessingPipe = NULL;
 			}
 
 			// unlink hardware queue and delete the transfer

src/add-ons/kernel/busses/usb/ehci.h

@@ -157,6 +157,7 @@ static	pci_module_info *			sPCIModule;
 		thread_id					fCleanupThread;
 		bool						fStopThreads;
 		ehci_qh *					fFreeListHead;
+		Pipe *						fProcessingPipe;
 
 		// Root Hub
 		EHCIRootHub *				fRootHub;

src/add-ons/kernel/busses/usb/ohci.cpp

@@ -71,6 +71,7 @@ OHCI::OHCI(pci_info *info, Stack *stack)
 		fFinishTransfersSem(-1),
 		fFinishThread(-1),
 		fStopFinishThread(false),
+		fProcessingPipe(NULL),
 		fRootHub(NULL),
 		fRootHubAddress(0),
 		fPortCount(0)
@@ -472,6 +473,10 @@ OHCI::CancelQueuedTransfers(Pipe *pipe, bool force)
 		list = next;
 	}
 
+	// wait for any transfers that might have made it before canceling
+	while (fProcessingPipe == pipe)
+		snooze(1000);
+
 	// notify the finisher so it can clean up the canceled transfers
 	release_sem_etc(fFinishTransfersSem, 1, B_DO_NOT_RESCHEDULE);
 	return B_OK;
@@ -1021,6 +1026,11 @@ OHCI::_FinishTransfers()
 				if (transfer == fLastTransfer)
 					fLastTransfer = lastTransfer;
 
+				// store the currently processing pipe here so we can wait
+				// in cancel if we are processing something on the target pipe
+				if (!transfer->canceled)
+					fProcessingPipe = transfer->transfer->TransferPipe();
+
 				transfer->link = NULL;
 				Unlock();
 			}
@@ -1071,6 +1081,7 @@ OHCI::_FinishTransfers()
 				}
 
 				transfer->transfer->Finished(callbackStatus, actualLength);
+				fProcessingPipe = NULL;
 			}
 
 			if (callbackStatus != B_OK) {

src/add-ons/kernel/busses/usb/ohci.h

@@ -163,6 +163,7 @@ static	pci_module_info *			sPCIModule;
 		sem_id						fFinishTransfersSem;
 		thread_id					fFinishThread;
 		bool						fStopFinishThread;
+		Pipe *						fProcessingPipe;
 
 		// Root Hub
 		OHCIRootHub *				fRootHub;

src/add-ons/kernel/busses/usb/uhci.cpp

@@ -335,6 +335,7 @@ UHCI::UHCI(pci_info *info, Stack *stack)
 		fFinishTransfersSem(-1),
 		fFinishThread(-1),
 		fStopThreads(false),
+		fProcessingPipe(NULL),
 		fFreeList(NULL),
 		fCleanupThread(-1),
 		fCleanupSem(-1),
@@ -795,6 +796,10 @@ UHCI::CancelQueuedTransfers(Pipe *pipe, bool force)
 		list = next;
 	}
 
+	// wait for any transfers that might have made it before canceling
+	while (fProcessingPipe == pipe)
+		snooze(1000);
+
 	// notify the finisher so it can clean up the canceled transfers
 	release_sem_etc(fFinishTransfersSem, 1, B_DO_NOT_RESCHEDULE);
 	return B_OK;
@@ -1340,6 +1345,11 @@ UHCI::FinishTransfers()
 				if (transfer == fLastTransfer)
 					fLastTransfer = lastTransfer;
 
+				// store the currently processing pipe here so we can wait
+				// in cancel if we are processing something on the target pipe
+				if (!transfer->canceled)
+					fProcessingPipe = transfer->transfer->TransferPipe();
+
 				transfer->link = NULL;
 				Unlock();
 			}
@@ -1399,6 +1409,7 @@ UHCI::FinishTransfers()
 				}
 
 				transfer->transfer->Finished(callbackStatus, actualLength);
+				fProcessingPipe = NULL;
 			}
 
 			// remove and free the hardware queue and its descriptors

src/add-ons/kernel/busses/usb/uhci.h

@@ -233,6 +233,7 @@ static	pci_module_info *			sPCIModule;
 		sem_id						fFinishTransfersSem;
 		thread_id					fFinishThread;
 		bool						fStopThreads;
+		Pipe *						fProcessingPipe;
 
 		transfer_data *				fFreeList;
 		thread_id					fCleanupThread;