* Added B_DELETE_IO_REQUEST flag, which causes the IORequest to be

deleted automatically when it's finished.
* Added IORequest::Create() for creating a IORequest on the heap
  (respectively the VIP heap).


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@27054 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/system/kernel/device_manager/io_requests.cpp

@@ -586,6 +586,13 @@ IORequest::~IORequest()
 }
 
 
+/* static */ IORequest*
+IORequest::Create(bool vip)
+{
+	return vip ? new(vip_io_alloc) IORequest : new(std::nothrow) IORequest;
+}
+
+
 status_t
 IORequest::Init(off_t offset, void* buffer, size_t length, bool write,
 	uint32 flags)
@@ -663,13 +670,12 @@ IORequest::CreateSubRequest(off_t parentOffset, off_t offset, size_t length,
 	}
 
 	// create subrequest
-	IORequest* subRequest = (fFlags & B_VIP_IO_REQUEST) != 0
-		? new(vip_io_alloc) IORequest : new(std::nothrow) IORequest;
+	IORequest* subRequest = Create((fFlags & B_VIP_IO_REQUEST) != 0);
 	if (subRequest == NULL)
 		return B_NO_MEMORY;
 
 	status_t error = subRequest->Init(offset, vecOffset, vecs + startVec,
-		endVec - startVec + 1, length, fIsWrite, fFlags);
+		endVec - startVec + 1, length, fIsWrite, fFlags & ~B_DELETE_IO_REQUEST);
 	if (error != B_OK) {
 		delete subRequest;
 		return error;
@@ -781,6 +787,7 @@ IORequest::NotifyFinished()
 	status_t status = fStatus;
 	size_t lastTransferredOffset = fRelativeParentOffset + fTransferSize;
 	bool partialTransfer = status != B_OK || fPartialTransfer;
+	bool deleteRequest = (fFlags & B_DELETE_IO_REQUEST) != 0;
 
 	// unblock waiters
 	fFinishedCondition.NotifyAll();
@@ -798,6 +805,9 @@ IORequest::NotifyFinished()
 		parent->SubRequestFinished(this, status, partialTransfer,
 			lastTransferredOffset);
 	}
+
+	if (deleteRequest)
+		delete this;
 }
 
 

src/system/kernel/device_manager/io_requests.h

@@ -22,6 +22,7 @@
 #define B_PHYSICAL_IO_REQUEST	0x01	/* buffer points to physical memory */
 #define B_VIP_IO_REQUEST		0x02	/* used by the page writer -- make sure
 										   allocations won't fail */
+#define B_DELETE_IO_REQUEST		0x04	/* delete request when finished */
 
 struct DMABuffer;
 struct IOOperation;
@@ -193,6 +194,7 @@ typedef struct IORequest io_request;
 typedef status_t (*io_request_finished_callback)(void* data,
 			io_request* request, status_t status, bool partialTransfer,
 			size_t transferEndOffset);
+			// TODO: Return type: status_t -> void
 typedef status_t (*io_request_iterate_callback)(void* data,
 			io_request* request, bool* _partialTransfer);
 
@@ -201,6 +203,8 @@ struct IORequest : IORequestChunk, DoublyLinkedListLinkImpl<IORequest> {
 								IORequest();
 	virtual						~IORequest();
 
+	static	IORequest*			Create(bool vip);
+
 			status_t			Init(off_t offset, void* buffer, size_t length,
 									bool write, uint32 flags);
 			status_t			Init(off_t offset, const iovec* vecs,