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--- xnu/xnu-4570.41.2/iokit/Kernel/IOSharedDataQueue.cpp
+++ xnu/xnu-1228/iokit/Kernel/IOSharedDataQueue.cpp
@@ -31,10 +31,6 @@
#include <IOKit/IOLib.h>
#include <IOKit/IOMemoryDescriptor.h>
-#ifdef enqueue
-#undef enqueue
-#endif
-
#ifdef dequeue
#undef dequeue
#endif
@@ -74,51 +70,23 @@
Boolean IOSharedDataQueue::initWithCapacity(UInt32 size)
{
IODataQueueAppendix * appendix;
- vm_size_t allocSize;
-
+
if (!super::init()) {
return false;
}
-
- _reserved = (ExpansionData *)IOMalloc(sizeof(struct ExpansionData));
- if (!_reserved) {
- return false;
- }
-
- if (size > UINT32_MAX - DATA_QUEUE_MEMORY_HEADER_SIZE - DATA_QUEUE_MEMORY_APPENDIX_SIZE) {
- return false;
- }
-
- allocSize = round_page(size + DATA_QUEUE_MEMORY_HEADER_SIZE + DATA_QUEUE_MEMORY_APPENDIX_SIZE);
-
- if (allocSize < size) {
- return false;
- }
-
- dataQueue = (IODataQueueMemory *)IOMallocAligned(allocSize, PAGE_SIZE);
+
+ dataQueue = (IODataQueueMemory *)IOMallocAligned(round_page_32(size + DATA_QUEUE_MEMORY_HEADER_SIZE + DATA_QUEUE_MEMORY_APPENDIX_SIZE), PAGE_SIZE);
if (dataQueue == 0) {
return false;
}
- bzero(dataQueue, allocSize);
dataQueue->queueSize = size;
-// dataQueue->head = 0;
-// dataQueue->tail = 0;
-
- if (!setQueueSize(size)) {
- return false;
- }
+ dataQueue->head = 0;
+ dataQueue->tail = 0;
appendix = (IODataQueueAppendix *)((UInt8 *)dataQueue + size + DATA_QUEUE_MEMORY_HEADER_SIZE);
appendix->version = 0;
-
- if (!notifyMsg) {
- notifyMsg = IOMalloc(sizeof(mach_msg_header_t));
- if (!notifyMsg)
- return false;
- }
- bzero(notifyMsg, sizeof(mach_msg_header_t));
-
+ notifyMsg = &(appendix->msgh);
setNotificationPort(MACH_PORT_NULL);
return true;
@@ -127,19 +95,10 @@
void IOSharedDataQueue::free()
{
if (dataQueue) {
- IOFreeAligned(dataQueue, round_page(getQueueSize() + DATA_QUEUE_MEMORY_HEADER_SIZE + DATA_QUEUE_MEMORY_APPENDIX_SIZE));
+ IOFreeAligned(dataQueue, round_page_32(dataQueue->queueSize + DATA_QUEUE_MEMORY_HEADER_SIZE + DATA_QUEUE_MEMORY_APPENDIX_SIZE));
dataQueue = NULL;
- if (notifyMsg) {
- IOFree(notifyMsg, sizeof(mach_msg_header_t));
- notifyMsg = NULL;
- }
- }
-
- if (_reserved) {
- IOFree (_reserved, sizeof(struct ExpansionData));
- _reserved = NULL;
- }
-
+ }
+
super::free();
}
@@ -148,7 +107,7 @@
IOMemoryDescriptor *descriptor = 0;
if (dataQueue != 0) {
- descriptor = IOMemoryDescriptor::withAddress(dataQueue, getQueueSize() + DATA_QUEUE_MEMORY_HEADER_SIZE + DATA_QUEUE_MEMORY_APPENDIX_SIZE, kIODirectionOutIn);
+ descriptor = IOMemoryDescriptor::withAddress(dataQueue, dataQueue->queueSize + DATA_QUEUE_MEMORY_HEADER_SIZE + DATA_QUEUE_MEMORY_APPENDIX_SIZE, kIODirectionOutIn);
}
return descriptor;
@@ -157,42 +116,25 @@
IODataQueueEntry * IOSharedDataQueue::peek()
{
- IODataQueueEntry *entry = 0;
- UInt32 headOffset;
- UInt32 tailOffset;
-
- if (!dataQueue) {
- return NULL;
- }
-
- // Read head and tail with acquire barrier
- headOffset = __c11_atomic_load((_Atomic UInt32 *)&dataQueue->head, __ATOMIC_RELAXED);
- tailOffset = __c11_atomic_load((_Atomic UInt32 *)&dataQueue->tail, __ATOMIC_ACQUIRE);
-
- if (headOffset != tailOffset) {
- IODataQueueEntry * head = 0;
+ IODataQueueEntry *entry = 0;
+
+ if (dataQueue && (dataQueue->head != dataQueue->tail)) {
+ IODataQueueEntry * head = 0;
UInt32 headSize = 0;
UInt32 headOffset = dataQueue->head;
- UInt32 queueSize = getQueueSize();
-
- if (headOffset >= queueSize) {
- return NULL;
- }
-
- head = (IODataQueueEntry *)((char *)dataQueue->queue + headOffset);
- headSize = head->size;
-
- // Check if there's enough room before the end of the queue for a header.
+ UInt32 queueSize = dataQueue->queueSize;
+
+ head = (IODataQueueEntry *)((char *)dataQueue->queue + headOffset);
+ headSize = head->size;
+
+ // Check if there's enough room before the end of the queue for a header.
// If there is room, check if there's enough room to hold the header and
// the data.
- if ((headOffset > UINT32_MAX - DATA_QUEUE_ENTRY_HEADER_SIZE) ||
- (headOffset + DATA_QUEUE_ENTRY_HEADER_SIZE > queueSize) ||
- (headOffset + DATA_QUEUE_ENTRY_HEADER_SIZE > UINT32_MAX - headSize) ||
- (headOffset + headSize + DATA_QUEUE_ENTRY_HEADER_SIZE > queueSize)) {
+ if ((headOffset + DATA_QUEUE_ENTRY_HEADER_SIZE > queueSize) ||
+ ((headOffset + headSize + DATA_QUEUE_ENTRY_HEADER_SIZE) > queueSize))
+ {
// No room for the header or the data, wrap to the beginning of the queue.
- // Note: wrapping even with the UINT32_MAX checks, as we have to support
- // queueSize of UINT32_MAX
entry = dataQueue->queue;
} else {
entry = head;
@@ -202,177 +144,60 @@
return entry;
}
-Boolean IOSharedDataQueue::enqueue(void * data, UInt32 dataSize)
-{
- UInt32 head;
- UInt32 tail;
- UInt32 newTail;
- const UInt32 entrySize = dataSize + DATA_QUEUE_ENTRY_HEADER_SIZE;
- IODataQueueEntry * entry;
-
- // Force a single read of head and tail
- head = __c11_atomic_load((_Atomic UInt32 *)&dataQueue->head, __ATOMIC_RELAXED);
- tail = __c11_atomic_load((_Atomic UInt32 *)&dataQueue->tail, __ATOMIC_RELAXED);
-
- // Check for overflow of entrySize
- if (dataSize > UINT32_MAX - DATA_QUEUE_ENTRY_HEADER_SIZE) {
- return false;
- }
- // Check for underflow of (getQueueSize() - tail)
- if (getQueueSize() < tail || getQueueSize() < head) {
- return false;
- }
-
- if ( tail >= head )
- {
- // Is there enough room at the end for the entry?
- if ((entrySize <= UINT32_MAX - tail) &&
- ((tail + entrySize) <= getQueueSize()) )
- {
- 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.
-
- 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 ( ( getQueueSize() - tail ) >= DATA_QUEUE_ENTRY_HEADER_SIZE )
- {
- ((IODataQueueEntry *)((UInt8 *)dataQueue->queue + tail))->size = dataSize;
- }
-
- 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;
- memcpy(&entry->data, data, dataSize);
- newTail = tail + entrySize;
- }
- else
- {
- return false; // queue is full
- }
- }
-
- // Update tail with release barrier
- __c11_atomic_store((_Atomic UInt32 *)&dataQueue->tail, newTail, __ATOMIC_RELEASE);
-
- // Send notification (via mach message) that data is available.
-
- if ( ( tail == head ) /* queue was empty prior to enqueue() */
- || ( tail == __c11_atomic_load((_Atomic UInt32 *)&dataQueue->head, __ATOMIC_RELAXED) ) ) /* queue was emptied during enqueue() */
- {
- sendDataAvailableNotification();
- }
-
- return true;
-}
-
Boolean IOSharedDataQueue::dequeue(void *data, UInt32 *dataSize)
{
Boolean retVal = TRUE;
IODataQueueEntry * entry = 0;
UInt32 entrySize = 0;
- UInt32 headOffset = 0;
- UInt32 tailOffset = 0;
UInt32 newHeadOffset = 0;
- if (!dataQueue) {
- return false;
- }
-
- // Read head and tail with acquire barrier
- tailOffset = __c11_atomic_load((_Atomic UInt32 *)&dataQueue->tail, __ATOMIC_RELAXED);
- headOffset = __c11_atomic_load((_Atomic UInt32 *)&dataQueue->head, __ATOMIC_ACQUIRE);
-
- if (headOffset != tailOffset) {
- IODataQueueEntry * head = 0;
- UInt32 headSize = 0;
- UInt32 queueSize = getQueueSize();
-
- if (headOffset > queueSize) {
- return false;
- }
-
- head = (IODataQueueEntry *)((char *)dataQueue->queue + headOffset);
- headSize = head->size;
-
- // we wrapped around to beginning, so read from there
- // either there was not even room for the header
- if ((headOffset > UINT32_MAX - DATA_QUEUE_ENTRY_HEADER_SIZE) ||
- (headOffset + DATA_QUEUE_ENTRY_HEADER_SIZE > queueSize) ||
- // or there was room for the header, but not for the data
- (headOffset + DATA_QUEUE_ENTRY_HEADER_SIZE > UINT32_MAX - headSize) ||
- (headOffset + headSize + DATA_QUEUE_ENTRY_HEADER_SIZE > queueSize)) {
- // Note: we have to wrap to the beginning even with the UINT32_MAX checks
- // because we have to support a queueSize of UINT32_MAX.
- entry = dataQueue->queue;
- entrySize = entry->size;
- if ((entrySize > UINT32_MAX - DATA_QUEUE_ENTRY_HEADER_SIZE) ||
- (entrySize + DATA_QUEUE_ENTRY_HEADER_SIZE > queueSize)) {
- return false;
+ if (dataQueue) {
+ if (dataQueue->head != dataQueue->tail) {
+ IODataQueueEntry * head = 0;
+ UInt32 headSize = 0;
+ UInt32 headOffset = dataQueue->head;
+ UInt32 queueSize = dataQueue->queueSize;
+
+ head = (IODataQueueEntry *)((char *)dataQueue->queue + headOffset);
+ headSize = head->size;
+
+ // we wraped around to beginning, so read from there
+ // either there was not even room for the header
+ if ((headOffset + DATA_QUEUE_ENTRY_HEADER_SIZE > queueSize) ||
+ // or there was room for the header, but not for the data
+ ((headOffset + headSize + DATA_QUEUE_ENTRY_HEADER_SIZE) > queueSize)) {
+ entry = dataQueue->queue;
+ entrySize = entry->size;
+ newHeadOffset = entrySize + DATA_QUEUE_ENTRY_HEADER_SIZE;
+ // else it is at the end
+ } else {
+ entry = head;
+ entrySize = entry->size;
+ newHeadOffset = headOffset + entrySize + DATA_QUEUE_ENTRY_HEADER_SIZE;
}
- newHeadOffset = entrySize + DATA_QUEUE_ENTRY_HEADER_SIZE;
- // else it is at the end
- } else {
- entry = head;
- entrySize = entry->size;
- if ((entrySize > UINT32_MAX - DATA_QUEUE_ENTRY_HEADER_SIZE) ||
- (entrySize + DATA_QUEUE_ENTRY_HEADER_SIZE > UINT32_MAX - headOffset) ||
- (entrySize + DATA_QUEUE_ENTRY_HEADER_SIZE + headOffset > queueSize)) {
- return false;
- }
- newHeadOffset = headOffset + entrySize + DATA_QUEUE_ENTRY_HEADER_SIZE;
- }
- }
-
- if (entry) {
- if (data) {
- if (dataSize) {
- if (entrySize <= *dataSize) {
- memcpy(data, &(entry->data), entrySize);
- __c11_atomic_store((_Atomic UInt32 *)&dataQueue->head, newHeadOffset, __ATOMIC_RELEASE);
+ }
+
+ if (entry) {
+ if (data) {
+ if (dataSize) {
+ if (entrySize <= *dataSize) {
+ memcpy(data, &(entry->data), entrySize);
+ dataQueue->head = newHeadOffset;
+ } else {
+ retVal = FALSE;
+ }
} else {
retVal = FALSE;
}
} else {
- retVal = FALSE;
+ dataQueue->head = newHeadOffset;
+ }
+
+ if (dataSize) {
+ *dataSize = entrySize;
}
} else {
- __c11_atomic_store((_Atomic UInt32 *)&dataQueue->head, newHeadOffset, __ATOMIC_RELEASE);
- }
-
- if (dataSize) {
- *dataSize = entrySize;
+ retVal = FALSE;
}
} else {
retVal = FALSE;
@@ -381,22 +206,6 @@
return retVal;
}
-UInt32 IOSharedDataQueue::getQueueSize()
-{
- if (!_reserved) {
- return 0;
- }
- return _reserved->queueSize;
-}
-
-Boolean IOSharedDataQueue::setQueueSize(UInt32 size)
-{
- if (!_reserved) {
- return false;
- }
- _reserved->queueSize = size;
- return true;
-}
OSMetaClassDefineReservedUnused(IOSharedDataQueue, 0);
OSMetaClassDefineReservedUnused(IOSharedDataQueue, 1);