#define IOKIT_ENABLE_SHARED_PTR
#define DISABLE_DATAQUEUE_WARNING
#include <IOKit/IODataQueue.h>
#undef DISABLE_DATAQUEUE_WARNING
#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
#endif
#ifdef dequeue
#undef dequeue
#endif
#define super OSObject
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;
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 = IONew(IODataQueueInternal, 1);
if (!notifyMsg) {
return false;
}
bzero(notifyMsg, sizeof(IODataQueueInternal));
((IODataQueueInternal *)notifyMsg)->queueSize = size;
dataQueue = (IODataQueueMemory *)IOMallocAligned(allocSize, PAGE_SIZE);
if (dataQueue == NULL) {
return false;
}
bzero(dataQueue, allocSize);
dataQueue->queueSize = size;
return true;
}
Boolean
IODataQueue::initWithEntries(UInt32 numEntries, UInt32 entrySize)
{
if ((entrySize > UINT32_MAX - DATA_QUEUE_ENTRY_HEADER_SIZE) ||
(numEntries > UINT32_MAX - 1) ||
(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) {
IOFreeAligned(dataQueue, round_page(((IODataQueueInternal *)notifyMsg)->queueSize + DATA_QUEUE_MEMORY_HEADER_SIZE));
dataQueue = NULL;
}
IODelete(notifyMsg, IODataQueueInternal, 1);
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;
if (dataSize > UINT32_MAX - DATA_QUEUE_ENTRY_HEADER_SIZE) {
return false;
}
tail = __c11_atomic_load((_Atomic UInt32 *)&dataQueue->tail, __ATOMIC_RELAXED);
head = __c11_atomic_load((_Atomic UInt32 *)&dataQueue->head, __ATOMIC_ACQUIRE);
queueSize = ((IODataQueueInternal *) notifyMsg)->queueSize;
if ((queueSize < tail) || (queueSize < head)) {
return false;
}
if (tail >= head) {
if ((entrySize <= UINT32_MAX - tail) &&
((tail + entrySize) <= queueSize)) {
entry = (IODataQueueEntry *)((UInt8 *)dataQueue->queue + tail);
entry->size = dataSize;
__nochk_memcpy(&entry->data, data, dataSize);
newTail = tail + entrySize;
} else if (head > entrySize) {
dataQueue->queue->size = dataSize;
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; }
} else {
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; }
}
__c11_atomic_store((_Atomic UInt32 *)&dataQueue->tail, newTail, __ATOMIC_RELEASE);
if (tail != head) {
__c11_atomic_thread_fence(__ATOMIC_SEQ_CST);
head = __c11_atomic_load((_Atomic UInt32 *)&dataQueue->head, __ATOMIC_RELAXED);
}
if (tail == head) {
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, MACH_SEND_TIMEOUT, MACH_MSG_TIMEOUT_NONE);
switch (kr) {
case MACH_SEND_TIMED_OUT: case MACH_MSG_SUCCESS:
case MACH_SEND_NO_BUFFER:
break;
default:
IOLog("%s: dataAvailableNotification failed - msg_send returned: %d\n", "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;
}