Structure containing parameters of a memory allocation.

Description

The internal data of an allocated device memory object must include a reference to implementation-specific resources, referred to as the memory object’s payload. Applications can also import and export that internal data to and from device memory objects to share data between Vulkan instances and other compatible APIs. A VkMemoryAllocateInfo structure defines a memory import operation if its pNext chain includes one of the following structures:

• VkImportMemoryWin32HandleInfoKHR with a non-zero handleType value
• VkImportMemoryFdInfoKHR with a non-zero handleType value
• VkImportMemoryHostPointerInfoEXT with a non-zero handleType value
• VkImportAndroidHardwareBufferInfoANDROID with a non-NULL buffer value

If the parameters define an import operation and the external handle type is EXTERNAL_MEMORY_HANDLE_TYPE_D3D11_TEXTURE_BIT, EXTERNAL_MEMORY_HANDLE_TYPE_D3D11_TEXTURE_KMT_BIT, or EXTERNAL_MEMORY_HANDLE_TYPE_D3D12_RESOURCE_BIT, allocationSize is ignored. The implementation must query the size of these allocations from the OS.

Whether device memory objects constructed via a memory import operation hold a reference to their payload depends on the properties of the handle type used to perform the import, as defined below for each valid handle type. Importing memory must not modify the content of the memory. Implementations must ensure that importing memory does not enable the importing Vulkan instance to access any memory or resources in other Vulkan instances other than that corresponding to the memory object imported. Implementations must also ensure accessing imported memory which has not been initialized does not allow the importing Vulkan instance to obtain data from the exporting Vulkan instance or vice-versa.

Importing memory must not increase overall heap usage within a system. However, it must affect the following per-process values:

• VkPhysicalDeviceMaintenance3Properties::maxMemoryAllocationCount
• VkPhysicalDeviceMemoryBudgetPropertiesEXT::heapUsage

When performing a memory import operation, it is the responsibility of the application to ensure the external handles and their associated payloads meet all valid usage requirements. However, implementations must perform sufficient validation of external handles and payloads to ensure that the operation results in a valid memory object which will not cause program termination, device loss, queue stalls, or corruption of other resources when used as allowed according to its allocation parameters. If the external handle provided does not meet these requirements, the implementation must fail the memory import operation with the error code ERROR_INVALID_EXTERNAL_HANDLE. If the parameters define an export operation and the external handle type is EXTERNAL_MEMORY_HANDLE_TYPE_ANDROID_HARDWARE_BUFFER_BIT_ANDROID, implementations should not strictly follow memoryTypeIndex. Instead, they should modify the allocation internally to use the required memory type for the application’s given usage. This is because for an export operation, there is currently no way for the client to know the memory type index before allocating.

Valid Usage

• The parameters must not define more than one import operation
• If the parameters do not define an import or export operation, allocationSize must be greater than 0
• If the parameters define an export operation and the handle type is not EXTERNAL_MEMORY_HANDLE_TYPE_ANDROID_HARDWARE_BUFFER_BIT_ANDROID, allocationSize must be greater than 0
• If the pNext chain includes a VkExportMemoryAllocateInfo structure, and any of the handle types specified in VkExportMemoryAllocateInfo::handleTypes require a dedicated allocation, as reported by GetPhysicalDeviceImageFormatProperties2 in VkExternalImageFormatProperties::externalMemoryProperties.externalMemoryFeatures, or by GetPhysicalDeviceExternalBufferProperties in VkExternalBufferProperties::externalMemoryProperties.externalMemoryFeatures, the pNext chain must include a VkMemoryDedicatedAllocateInfo or VkDedicatedAllocationMemoryAllocateInfoNV structure with either its image or buffer member set to a value other than NULL_HANDLE
• If the pNext chain includes a VkExportMemoryAllocateInfo structure, it must not include a VkExportMemoryAllocateInfoNV or VkExportMemoryWin32HandleInfoNV structure
• If the pNext chain includes a VkImportMemoryWin32HandleInfoKHR structure, it must not include a VkImportMemoryWin32HandleInfoNV structure
• If the parameters define an import operation, the external handle specified was created by the Vulkan API, and the external handle type is EXTERNAL_MEMORY_HANDLE_TYPE_OPAQUE_FD_BIT, then the values of allocationSize and memoryTypeIndex must match those specified when the payload being imported was created
• If the parameters define an import operation and the external handle specified was created by the Vulkan API, the device mask specified by VkMemoryAllocateFlagsInfo must match the mask specified when the payload being imported was allocated
• If the parameters define an import operation and the external handle specified was created by the Vulkan API, the list of physical devices that comprise the logical device passed to AllocateMemory must match the list of physical devices that comprise the logical device on which the payload was originally allocated
• If the parameters define an import operation and the external handle is an NT handle or a global share handle created outside of the Vulkan API, the value of memoryTypeIndex must be one of those returned by GetMemoryWin32HandlePropertiesKHR
• If the parameters define an import operation, the external handle was created by the Vulkan API, and the external handle type is EXTERNAL_MEMORY_HANDLE_TYPE_OPAQUE_WIN32_BIT or EXTERNAL_MEMORY_HANDLE_TYPE_OPAQUE_WIN32_KMT_BIT, then the values of allocationSize and memoryTypeIndex must match those specified when the payload being imported was created
• If the parameters define an import operation and the external handle type is EXTERNAL_MEMORY_HANDLE_TYPE_D3D12_HEAP_BIT, allocationSize must match the size specified when creating the Direct3D 12 heap from which the payload was extracted
• If the parameters define an import operation and the external handle is a POSIX file descriptor created outside of the Vulkan API, the value of memoryTypeIndex must be one of those returned by GetMemoryFdPropertiesKHR
• If the protectedMemory feature is not enabled, the VkMemoryAllocateInfo::memoryTypeIndex must not indicate a memory type that reports MEMORY_PROPERTY_PROTECTED_BIT
• If the parameters define an import operation and the external handle is a host pointer, the value of memoryTypeIndex must be one of those returned by GetMemoryHostPointerPropertiesEXT
• If the parameters define an import operation and the external handle is a host pointer, allocationSize must be an integer multiple of VkPhysicalDeviceExternalMemoryHostPropertiesEXT::minImportedHostPointerAlignment
• If the parameters define an import operation and the external handle is a host pointer, the pNext chain must not include a VkDedicatedAllocationMemoryAllocateInfoNV structure with either its image or buffer field set to a value other than NULL_HANDLE
• If the parameters define an import operation and the external handle is a host pointer, the pNext chain must not include a VkMemoryDedicatedAllocateInfo structure with either its image or buffer field set to a value other than NULL_HANDLE
• If the parameters define an import operation and the external handle type is EXTERNAL_MEMORY_HANDLE_TYPE_ANDROID_HARDWARE_BUFFER_BIT_ANDROID, allocationSize must be the size returned by GetAndroidHardwareBufferPropertiesANDROID for the Android hardware buffer
• If the parameters define an import operation and the external handle type is EXTERNAL_MEMORY_HANDLE_TYPE_ANDROID_HARDWARE_BUFFER_BIT_ANDROID, and the pNext chain does not include a VkMemoryDedicatedAllocateInfo structure or VkMemoryDedicatedAllocateInfo::image is NULL_HANDLE, the Android hardware buffer must have a AHardwareBuffer_Desc::format of AHARDWAREBUFFER_FORMAT_BLOB and a AHardwareBuffer_Desc::usage that includes AHARDWAREBUFFER_USAGE_GPU_DATA_BUFFER
• If the parameters define an import operation and the external handle type is EXTERNAL_MEMORY_HANDLE_TYPE_ANDROID_HARDWARE_BUFFER_BIT_ANDROID, memoryTypeIndex must be one of those returned by GetAndroidHardwareBufferPropertiesANDROID for the Android hardware buffer
• If the parameters do not define an import operation, and the pNext chain includes a VkExportMemoryAllocateInfo structure with EXTERNAL_MEMORY_HANDLE_TYPE_ANDROID_HARDWARE_BUFFER_BIT_ANDROID included in its handleTypes member, and the pNext chain includes a VkMemoryDedicatedAllocateInfo structure with image not equal to NULL_HANDLE, then allocationSize must be 0
• If the parameters define an export operation, the handle type is EXTERNAL_MEMORY_HANDLE_TYPE_ANDROID_HARDWARE_BUFFER_BIT_ANDROID, and the pNext does not include a VkMemoryDedicatedAllocateInfo structure, allocationSize must be greater than 0
• If the parameters define an export operation, the handle type is EXTERNAL_MEMORY_HANDLE_TYPE_ANDROID_HARDWARE_BUFFER_BIT_ANDROID, and the pNext chain includes a VkMemoryDedicatedAllocateInfo structure with buffer set to a valid VkBuffer object, allocationSize must be greater than 0
• If the parameters define an import operation, the external handle is an Android hardware buffer, and the pNext chain includes a VkMemoryDedicatedAllocateInfo with image that is not NULL_HANDLE, the Android hardware buffer’s AHardwareBuffer::usage must include at least one of AHARDWAREBUFFER_USAGE_GPU_FRAMEBUFFER, AHARDWAREBUFFER_USAGE_GPU_SAMPLED_IMAGE or AHARDWAREBUFFER_USAGE_GPU_DATA_BUFFER
• If the parameters define an import operation, the external handle is an Android hardware buffer, and the pNext chain includes a VkMemoryDedicatedAllocateInfo with image that is not NULL_HANDLE, the format of image must be FORMAT_UNDEFINED or the format returned by GetAndroidHardwareBufferPropertiesANDROID in VkAndroidHardwareBufferFormatPropertiesANDROID::format for the Android hardware buffer
• If the parameters define an import operation, the external handle is an Android hardware buffer, and the pNext chain includes a VkMemoryDedicatedAllocateInfo structure with image that is not NULL_HANDLE, the width, height, and array layer dimensions of image and the Android hardware buffer’s AHardwareBuffer_Desc must be identical
• If the parameters define an import operation, the external handle is an Android hardware buffer, and the pNext chain includes a VkMemoryDedicatedAllocateInfo structure with image that is not NULL_HANDLE, and the Android hardware buffer’s AHardwareBuffer::usage includes AHARDWAREBUFFER_USAGE_GPU_MIPMAP_COMPLETE, the image must have a complete mipmap chain
• If the parameters define an import operation, the external handle is an Android hardware buffer, and the pNext chain includes a VkMemoryDedicatedAllocateInfo structure with image that is not NULL_HANDLE, and the Android hardware buffer’s AHardwareBuffer::usage does not include AHARDWAREBUFFER_USAGE_GPU_MIPMAP_COMPLETE, the image must have exactly one mipmap level
• If the parameters define an import operation, the external handle is an Android hardware buffer, and the pNext chain includes a VkMemoryDedicatedAllocateInfo structure with image that is not NULL_HANDLE, each bit set in the usage of image must be listed in AHardwareBuffer Usage Equivalence, and if there is a corresponding AHARDWAREBUFFER_USAGE bit listed that bit must be included in the Android hardware buffer’s AHardwareBuffer_Desc::usage
• If VkMemoryOpaqueCaptureAddressAllocateInfo::opaqueCaptureAddress is not zero, VkMemoryAllocateFlagsInfo::flags must include MEMORY_ALLOCATE_DEVICE_ADDRESS_CAPTURE_REPLAY_BIT
• If VkMemoryAllocateFlagsInfo::flags includes MEMORY_ALLOCATE_DEVICE_ADDRESS_CAPTURE_REPLAY_BIT, the bufferDeviceAddressCaptureReplay feature must be enabled
• If VkMemoryAllocateFlagsInfo::flags includes MEMORY_ALLOCATE_DEVICE_ADDRESS_BIT, the bufferDeviceAddress feature must be enabled
• If the pNext chain includes a VkImportMemoryHostPointerInfoEXT structure, VkMemoryOpaqueCaptureAddressAllocateInfo::opaqueCaptureAddress must be zero
• If the parameters define an import operation, VkMemoryOpaqueCaptureAddressAllocateInfo::opaqueCaptureAddress must be zero
• If the pNext chain includes a VkExportMetalObjectCreateInfoEXT structure, its exportObjectType member must be EXPORT_METAL_OBJECT_TYPE_METAL_BUFFER_BIT_EXT

Valid Usage (Implicit)

• sType must be STRUCTURE_TYPE_MEMORY_ALLOCATE_INFO
• Each pNext member of any structure (including this one) in the pNext chain must be either NULL or a pointer to a valid instance of VkDedicatedAllocationMemoryAllocateInfoNV, VkExportMemoryAllocateInfo, VkExportMemoryAllocateInfoNV, VkExportMemoryWin32HandleInfoKHR, VkExportMemoryWin32HandleInfoNV, VkExportMetalObjectCreateInfoEXT, VkImportAndroidHardwareBufferInfoANDROID, VkImportMemoryFdInfoKHR, VkImportMemoryHostPointerInfoEXT, VkImportMemoryWin32HandleInfoKHR, VkImportMemoryWin32HandleInfoNV, VkImportMetalBufferInfoEXT, VkMemoryAllocateFlagsInfo, VkMemoryDedicatedAllocateInfo, VkMemoryOpaqueCaptureAddressAllocateInfo, or VkMemoryPriorityAllocateInfoEXT
• The sType value of each struct in the pNext chain must be unique, with the exception of structures of type VkExportMetalObjectCreateInfoEXT

See Also

AllocateMemory

Layout

struct VkMemoryAllocateInfo {
    VkStructureType sType;
    void const * pNext;
    VkDeviceSize allocationSize;
    uint32_t memoryTypeIndex;
}