Alternate function for IOMemoryDescriptor::withAddress ?

Question

Created Apr ’21

Replies 4

Boosts 0

Participants 4

Hi ,
I am trying to write dext code for my existing Kext , i see "IOMemoryDescriptor::withAddress" being used , I dont find any alternatives in "DriverKit", Is there any others ways to achieve this,

Any input is appriciated ,

Thanks,
revan

Answered by in 669970022

Code Block C++uint8_t data = { 1, 2, 3, 4 };
uint64_t dataSize = 4;
IOBufferMemoryDescriptor* buffer = nullptr;
uint8_t pipeMaxPacketSize = 0;
uint64_t addressValue = 0;
uint64_t length = 0;
ivars->interface->CreateIOBuffer(kIOMemoryDirectionInOut, pipeMaxPacketSize, &buffer);
(buffer)->Map(0, 0, 0, 0, &addressValue, &length);
memcpy((uint8_t*)addressValue, data, dataSize);

Boost

Answer 1

OP

Apple

Apr ’21

Accepted Answer

Code Block C++uint8_t data = { 1, 2, 3, 4 };
uint64_t dataSize = 4;
IOBufferMemoryDescriptor* buffer = nullptr;
uint8_t pipeMaxPacketSize = 0;
uint64_t addressValue = 0;
uint64_t length = 0;
ivars->interface->CreateIOBuffer(kIOMemoryDirectionInOut, pipeMaxPacketSize, &buffer);
(buffer)->Map(0, 0, 0, 0, &addressValue, &length);
memcpy((uint8_t*)addressValue, data, dataSize);

0

Answer 2

KivancG OP

Nov ’23

I agree with the necessity of that function "IOMemoryDescriptor::withAddress" in DriverKit

0

Answer 3

fredericWu OP

Feb ’24

Hi,

BufferMemoryDescriptorAME_Module = NULL;

IOMemoryMap *MemMap;

BufferMemoryDescriptorAME_Module= IOBufferMemoryDescriptor::inTaskWithPhysicalMask(

                                 // task to hold the memory

                                 kernel_task,

                                 // options

                                 kIOMemoryPhysicallyContiguous,

                                 // size

                                 Total_memory_size)

        BufferMemoryDescriptorAME_Module->prepare(kIODirectionInOut);

        MemMap = BufferMemoryDescriptorAME_Module->map(kIOMapInhibitCache);

        logicalAddressAME_Module = (UInt8 *) MemMap->getVirtualAddress();

        physicalAddressAME_Module = MemMap->getPhysicalAddress();

I am trying to write Dext code for my existing Kext，How to convert this code to be compatible with Dext？

Thanks,

Frederic

0

Answer 4