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--- xnu/xnu-12377.101.15/iokit/Kernel/IODataQueue.cpp
+++ xnu/xnu-344.2/iokit/Kernel/IODataQueue.cpp
@@ -1,50 +1,29 @@
/*
* Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
*
- * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
- *
- * This file contains Original Code and/or Modifications of Original Code
- * as defined in and that are subject to the Apple Public Source License
- * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. The rights granted to you under the License
- * may not be used to create, or enable the creation or redistribution of,
- * unlawful or unlicensed copies of an Apple operating system, or to
- * circumvent, violate, or enable the circumvention or violation of, any
- * terms of an Apple operating system software license agreement.
- *
- * Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this file.
- *
- * The Original Code and all software distributed under the License are
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * @APPLE_LICENSE_HEADER_START@
+ *
+ * The contents of this file constitute Original Code as defined in and
+ * are subject to the Apple Public Source License Version 1.1 (the
+ * "License"). You may not use this file except in compliance with the
+ * License. Please obtain a copy of the License at
+ * http://www.apple.com/publicsource and read it before using this file.
+ *
+ * This Original Code and all software distributed under the License are
+ * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
- * limitations under the License.
- *
- * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
+ * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
+ * License for the specific language governing rights and limitations
+ * under the License.
+ *
+ * @APPLE_LICENSE_HEADER_END@
*/
-#define IOKIT_ENABLE_SHARED_PTR
-
-#define DISABLE_DATAQUEUE_WARNING
-
#include <IOKit/IODataQueue.h>
-
-#undef DISABLE_DATAQUEUE_WARNING
-#include <vm/vm_kern_xnu.h>
-
#include <IOKit/IODataQueueShared.h>
#include <IOKit/IOLib.h>
#include <IOKit/IOMemoryDescriptor.h>
-#include <libkern/OSAtomic.h>
-#include <libkern/c++/OSSharedPtr.h>
-
-struct IODataQueueInternal {
- mach_msg_header_t msg;
- UInt32 queueSize;
-};
#ifdef enqueue
#undef enqueue
@@ -58,249 +37,192 @@
OSDefineMetaClassAndStructors(IODataQueue, OSObject)
-OSSharedPtr<IODataQueue>
-IODataQueue::withCapacity(UInt32 size)
-{
- OSSharedPtr<IODataQueue> dataQueue = OSMakeShared<IODataQueue>();
-
- if (dataQueue) {
- if (!dataQueue->initWithCapacity(size)) {
- return nullptr;
- }
- }
-
- return dataQueue;
-}
-
-OSSharedPtr<IODataQueue>
-IODataQueue::withEntries(UInt32 numEntries, UInt32 entrySize)
-{
- OSSharedPtr<IODataQueue> dataQueue = OSMakeShared<IODataQueue>();
-
- if (dataQueue) {
- if (!dataQueue->initWithEntries(numEntries, entrySize)) {
- return nullptr;
- }
- }
-
- return dataQueue;
-}
-
-Boolean
-IODataQueue::initWithCapacity(UInt32 size)
-{
- vm_size_t allocSize = 0;
- kern_return_t kr;
-
- if (!super::init()) {
- return false;
- }
-
- if (size > UINT32_MAX - DATA_QUEUE_MEMORY_HEADER_SIZE) {
- return false;
- }
-
- allocSize = round_page(size + DATA_QUEUE_MEMORY_HEADER_SIZE);
-
- if (allocSize < size) {
- return false;
- }
-
- assert(!notifyMsg);
- notifyMsg = IOMallocType(IODataQueueInternal);
- ((IODataQueueInternal *)notifyMsg)->queueSize = size;
-
- kr = kmem_alloc(kernel_map, (vm_offset_t *)&dataQueue, allocSize,
- (kma_flags_t)(KMA_DATA_SHARED | KMA_ZERO), IOMemoryTag(kernel_map));
- if (kr != KERN_SUCCESS) {
- return false;
- }
-
- dataQueue->queueSize = size;
-// dataQueue->head = 0;
-// dataQueue->tail = 0;
-
- return true;
-}
-
-Boolean
-IODataQueue::initWithEntries(UInt32 numEntries, UInt32 entrySize)
-{
- // Checking overflow for (numEntries + 1)*(entrySize + DATA_QUEUE_ENTRY_HEADER_SIZE):
- // check (entrySize + DATA_QUEUE_ENTRY_HEADER_SIZE)
- if ((entrySize > UINT32_MAX - DATA_QUEUE_ENTRY_HEADER_SIZE) ||
- // check (numEntries + 1)
- (numEntries > UINT32_MAX - 1) ||
- // check (numEntries + 1)*(entrySize + DATA_QUEUE_ENTRY_HEADER_SIZE)
- (entrySize + DATA_QUEUE_ENTRY_HEADER_SIZE > UINT32_MAX / (numEntries + 1))) {
- return false;
- }
-
- return initWithCapacity((numEntries + 1) * (DATA_QUEUE_ENTRY_HEADER_SIZE + entrySize));
-}
-
-void
-IODataQueue::free()
-{
- if (notifyMsg) {
- if (dataQueue) {
- kmem_free(kernel_map, (vm_offset_t)dataQueue,
- round_page(((IODataQueueInternal *)notifyMsg)->queueSize +
- DATA_QUEUE_MEMORY_HEADER_SIZE));
- dataQueue = NULL;
- }
-
- IOFreeType(notifyMsg, IODataQueueInternal);
- notifyMsg = NULL;
- }
-
- super::free();
-
- return;
-}
-
-Boolean
-IODataQueue::enqueue(void * data, UInt32 dataSize)
-{
- UInt32 head;
- UInt32 tail;
- UInt32 newTail;
- const UInt32 entrySize = dataSize + DATA_QUEUE_ENTRY_HEADER_SIZE;
- UInt32 queueSize;
- IODataQueueEntry * entry;
-
- // Check for overflow of entrySize
- if (dataSize > UINT32_MAX - DATA_QUEUE_ENTRY_HEADER_SIZE) {
- return false;
- }
-
- // Force a single read of head and tail
- // See rdar://problem/40780584 for an explanation of relaxed/acquire barriers
- tail = __c11_atomic_load((_Atomic UInt32 *)&dataQueue->tail, __ATOMIC_RELAXED);
- head = __c11_atomic_load((_Atomic UInt32 *)&dataQueue->head, __ATOMIC_ACQUIRE);
-
- // Check for underflow of (dataQueue->queueSize - tail)
- queueSize = ((IODataQueueInternal *) notifyMsg)->queueSize;
- if ((queueSize < tail) || (queueSize < head)) {
- return false;
- }
-
- if (tail >= head) {
- // Is there enough room at the end for the entry?
- if ((entrySize <= UINT32_MAX - tail) &&
- ((tail + entrySize) <= queueSize)) {
- entry = (IODataQueueEntry *)((UInt8 *)dataQueue->queue + tail);
-
- entry->size = dataSize;
- __nochk_memcpy(&entry->data, data, dataSize);
-
- // The tail can be out of bound when the size of the new entry
- // exactly matches the available space at the end of the queue.
- // The tail can range from 0 to dataQueue->queueSize inclusive.
-
- newTail = tail + entrySize;
- } else if (head > entrySize) { // Is there enough room at the beginning?
- // Wrap around to the beginning, but do not allow the tail to catch
- // up to the head.
-
- dataQueue->queue->size = dataSize;
-
- // We need to make sure that there is enough room to set the size before
- // doing this. The user client checks for this and will look for the size
- // at the beginning if there isn't room for it at the end.
-
- if ((queueSize - tail) >= DATA_QUEUE_ENTRY_HEADER_SIZE) {
- ((IODataQueueEntry *)((UInt8 *)dataQueue->queue + tail))->size = dataSize;
- }
-
- __nochk_memcpy(&dataQueue->queue->data, data, dataSize);
- newTail = entrySize;
- } else {
- return false; // queue is full
- }
- } else {
- // Do not allow the tail to catch up to the head when the queue is full.
- // That's why the comparison uses a '>' rather than '>='.
-
- if ((head - tail) > entrySize) {
- entry = (IODataQueueEntry *)((UInt8 *)dataQueue->queue + tail);
-
- entry->size = dataSize;
- __nochk_memcpy(&entry->data, data, dataSize);
- newTail = tail + entrySize;
- } else {
- return false; // queue is full
- }
- }
-
- // Publish the data we just enqueued
- __c11_atomic_store((_Atomic UInt32 *)&dataQueue->tail, newTail, __ATOMIC_RELEASE);
-
- if (tail != head) {
- //
- // The memory barrier below paris with the one in ::dequeue
- // so that either our store to the tail cannot be missed by
- // the next dequeue attempt, or we will observe the dequeuer
- // making the queue empty.
- //
- // Of course, if we already think the queue is empty,
- // there's no point paying this extra cost.
- //
- __c11_atomic_thread_fence(__ATOMIC_SEQ_CST);
- head = __c11_atomic_load((_Atomic UInt32 *)&dataQueue->head, __ATOMIC_RELAXED);
- }
-
- if (tail == head) {
- // Send notification (via mach message) that data is now available.
- sendDataAvailableNotification();
- }
- return true;
-}
-
-void
-IODataQueue::setNotificationPort(mach_port_t port)
-{
- mach_msg_header_t * msgh;
-
- msgh = &((IODataQueueInternal *) notifyMsg)->msg;
- bzero(msgh, sizeof(mach_msg_header_t));
- msgh->msgh_bits = MACH_MSGH_BITS(MACH_MSG_TYPE_COPY_SEND, 0);
- msgh->msgh_size = sizeof(mach_msg_header_t);
- msgh->msgh_remote_port = port;
-}
-
-void
-IODataQueue::sendDataAvailableNotification()
-{
- kern_return_t kr;
- mach_msg_header_t * msgh;
-
- msgh = &((IODataQueueInternal *) notifyMsg)->msg;
- if (msgh->msgh_remote_port) {
- kr = mach_msg_send_from_kernel_with_options(msgh, msgh->msgh_size,
- MACH64_SEND_TIMEOUT, MACH_MSG_TIMEOUT_NONE);
- switch (kr) {
- case MACH_SEND_TIMED_OUT: // Notification already sent
- case MACH_MSG_SUCCESS:
- case MACH_SEND_NO_BUFFER:
- break;
- default:
- IOLog("%s: dataAvailableNotification failed - msg_send returned: %d\n", /*getName()*/ "IODataQueue", kr);
- break;
- }
- }
-}
-
-OSSharedPtr<IOMemoryDescriptor>
-IODataQueue::getMemoryDescriptor()
-{
- OSSharedPtr<IOMemoryDescriptor> descriptor;
- UInt32 queueSize;
-
- queueSize = ((IODataQueueInternal *) notifyMsg)->queueSize;
- if (dataQueue != NULL) {
- descriptor = IOMemoryDescriptor::withAddress(dataQueue, queueSize + DATA_QUEUE_MEMORY_HEADER_SIZE, kIODirectionOutIn);
- }
-
- return descriptor;
-}
+IODataQueue *IODataQueue::withCapacity(UInt32 size)
+{
+ IODataQueue *dataQueue = new IODataQueue;
+
+ if (dataQueue) {
+ if (!dataQueue->initWithCapacity(size)) {
+ dataQueue->release();
+ dataQueue = 0;
+ }
+ }
+
+ return dataQueue;
+}
+
+IODataQueue *IODataQueue::withEntries(UInt32 numEntries, UInt32 entrySize)
+{
+ IODataQueue *dataQueue = new IODataQueue;
+
+ if (dataQueue) {
+ if (!dataQueue->initWithEntries(numEntries, entrySize)) {
+ dataQueue->release();
+ dataQueue = 0;
+ }
+ }
+
+ return dataQueue;
+}
+
+Boolean IODataQueue::initWithCapacity(UInt32 size)
+{
+ if (!super::init()) {
+ return false;
+ }
+
+ dataQueue = (IODataQueueMemory *)IOMallocAligned(round_page(size + DATA_QUEUE_MEMORY_HEADER_SIZE), PAGE_SIZE);
+ if (dataQueue == 0) {
+ return false;
+ }
+
+ dataQueue->queueSize = size;
+ dataQueue->head = 0;
+ dataQueue->tail = 0;
+
+ return true;
+}
+
+Boolean IODataQueue::initWithEntries(UInt32 numEntries, UInt32 entrySize)
+{
+ return (initWithCapacity((numEntries + 1) * (DATA_QUEUE_ENTRY_HEADER_SIZE + entrySize)));
+}
+
+void IODataQueue::free()
+{
+ if (dataQueue) {
+ IOFreeAligned(dataQueue, round_page(dataQueue->queueSize + DATA_QUEUE_MEMORY_HEADER_SIZE));
+ }
+
+ super::free();
+
+ return;
+}
+
+Boolean IODataQueue::enqueue(void * data, UInt32 dataSize)
+{
+ const UInt32 head = dataQueue->head; // volatile
+ const UInt32 tail = dataQueue->tail;
+ const UInt32 entrySize = dataSize + DATA_QUEUE_ENTRY_HEADER_SIZE;
+ IODataQueueEntry * entry;
+
+ if ( tail >= head )
+ {
+ // Is there enough room at the end for the entry?
+ if ( (tail + entrySize) <= dataQueue->queueSize )
+ {
+ entry = (IODataQueueEntry *)((UInt8 *)dataQueue->queue + tail);
+
+ entry->size = dataSize;
+ memcpy(&entry->data, data, dataSize);
+
+ // The tail can be out of bound when the size of the new entry
+ // exactly matches the available space at the end of the queue.
+ // The tail can range from 0 to dataQueue->queueSize inclusive.
+
+ dataQueue->tail += entrySize;
+ }
+ else if ( head > entrySize ) // Is there enough room at the beginning?
+ {
+ // Wrap around to the beginning, but do not allow the tail to catch
+ // up to the head.
+
+ dataQueue->queue->size = dataSize;
+
+ // We need to make sure that there is enough room to set the size before
+ // doing this. The user client checks for this and will look for the size
+ // at the beginning if there isn't room for it at the end.
+
+ if ( ( dataQueue->queueSize - tail ) >= DATA_QUEUE_ENTRY_HEADER_SIZE )
+ {
+ ((IODataQueueEntry *)((UInt8 *)dataQueue->queue + tail))->size = dataSize;
+ }
+
+ memcpy(&dataQueue->queue->data, data, dataSize);
+ dataQueue->tail = entrySize;
+ }
+ else
+ {
+ return false; // queue is full
+ }
+ }
+ else
+ {
+ // Do not allow the tail to catch up to the head when the queue is full.
+ // That's why the comparison uses a '>' rather than '>='.
+
+ if ( (head - tail) > entrySize )
+ {
+ entry = (IODataQueueEntry *)((UInt8 *)dataQueue->queue + tail);
+
+ entry->size = dataSize;
+ memcpy(&entry->data, data, dataSize);
+ dataQueue->tail += entrySize;
+ }
+ else
+ {
+ return false; // queue is full
+ }
+ }
+
+ // Send notification (via mach message) that data is available.
+
+ if ( ( head == tail ) /* queue was empty prior to enqueue() */
+ || ( dataQueue->head == tail ) ) /* queue was emptied during enqueue() */
+ {
+ sendDataAvailableNotification();
+ }
+
+ return true;
+}
+
+void IODataQueue::setNotificationPort(mach_port_t port)
+{
+ static struct _notifyMsg init_msg = { {
+ MACH_MSGH_BITS(MACH_MSG_TYPE_COPY_SEND, 0),
+ sizeof (struct _notifyMsg),
+ MACH_PORT_NULL,
+ MACH_PORT_NULL,
+ 0,
+ 0
+ } };
+
+ if (notifyMsg == 0) {
+ notifyMsg = IOMalloc(sizeof(struct _notifyMsg));
+ }
+
+ *((struct _notifyMsg *)notifyMsg) = init_msg;
+
+ ((struct _notifyMsg *)notifyMsg)->h.msgh_remote_port = port;
+}
+
+void IODataQueue::sendDataAvailableNotification()
+{
+ kern_return_t kr;
+ mach_msg_header_t * msgh;
+
+ msgh = (mach_msg_header_t *)notifyMsg;
+ if (msgh) {
+ kr = mach_msg_send_from_kernel(msgh, msgh->msgh_size);
+ switch(kr) {
+ case MACH_SEND_TIMED_OUT: // Notification already sent
+ case MACH_MSG_SUCCESS:
+ break;
+ default:
+ IOLog("%s: dataAvailableNotification failed - msg_send returned: %d\n", /*getName()*/"IODataQueue", kr);
+ break;
+ }
+ }
+}
+
+IOMemoryDescriptor *IODataQueue::getMemoryDescriptor()
+{
+ IOMemoryDescriptor *descriptor = 0;
+
+ if (dataQueue != 0) {
+ descriptor = IOMemoryDescriptor::withAddress(dataQueue, dataQueue->queueSize + DATA_QUEUE_MEMORY_HEADER_SIZE, kIODirectionOutIn);
+ }
+
+ return descriptor;
+}
+