Package org.lwjgl.vulkan

Class NVExternalMemoryRdma

java.lang.Object

org.lwjgl.vulkan.NVExternalMemoryRdma

public class NVExternalMemoryRdma
extends java.lang.Object

This extension adds support for allocating memory which can be used for remote direct memory access (RDMA) from other devices.

Examples

 VkPhysicalDeviceMemoryBudgetPropertiesEXT memoryBudgetProperties = { VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_MEMORY_BUDGET_PROPERTIES_EXT };
 VkPhysicalDeviceMemoryProperties2 memoryProperties2 = { VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_MEMORY_PROPERTIES_2, &memoryBudgetProperties };
 vkGetPhysicalDeviceMemoryProperties2(physicalDevice, &memoryProperties2);
 uint32_t heapIndex = (uint32_t)-1;
 for (uint32_t memoryType = 0; memoryType < memoryProperties2.memoryProperties.memoryTypeCount; memoryType++) {
     if (memoryProperties2.memoryProperties.memoryTypes[memoryType].propertyFlags & VK_MEMORY_PROPERTY_RDMA_CAPABLE_BIT_NV) {
         heapIndex = memoryProperties2.memoryProperties.memoryTypes[memoryType].heapIndex;
         break;
     }
 }
 if ((heapIndex == (uint32_t)-1) ||
     (memoryBudgetProperties.heapBudget[heapIndex] < size)) {
     return;
 }
 
 VkPhysicalDeviceExternalBufferInfo externalBufferInfo = { VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_EXTERNAL_BUFFER_INFO };
 externalBufferInfo.usage = VK_BUFFER_USAGE_TRANSFER_SRC_BIT | VK_BUFFER_USAGE_TRANSFER_DST_BIT;
 externalBufferInfo.handleType = VK_EXTERNAL_MEMORY_HANDLE_TYPE_RDMA_ADDRESS_BIT_NV;
 
 VkExternalBufferProperties externalBufferProperties = { VK_STRUCTURE_TYPE_EXTERNAL_BUFFER_PROPERTIES };
 vkGetPhysicalDeviceExternalBufferProperties(physicalDevice, &externalBufferInfo, &externalBufferProperties);
 
 if (!(externalBufferProperties.externalMemoryProperties.externalMemoryFeatures & VK_EXTERNAL_MEMORY_FEATURE_EXPORTABLE_BIT)) {
     return;
 }
 
 VkExternalMemoryBufferCreateInfo externalMemoryBufferCreateInfo = { VK_STRUCTURE_TYPE_EXTERNAL_MEMORY_BUFFER_CREATE_INFO };
 externalMemoryBufferCreateInfo.handleTypes = VK_EXTERNAL_MEMORY_HANDLE_TYPE_RDMA_ADDRESS_BIT_NV;
 
 VkBufferCreateInfo bufferCreateInfo = { VK_STRUCTURE_TYPE_BUFFER_CREATE_INFO, &externalMemoryBufferCreateInfo };
 bufferCreateInfo.size = size;
 bufferCreateInfo.usage = VK_BUFFER_USAGE_TRANSFER_SRC_BIT | VK_BUFFER_USAGE_TRANSFER_DST_BIT;
 
 VkMemoryRequirements mem_reqs;
 vkCreateBuffer(device, &bufferCreateInfo, NULL, &buffer);
 vkGetBufferMemoryRequirements(device, buffer, &mem_reqs);
 
 VkExportMemoryAllocateInfo exportMemoryAllocateInfo = { VK_STRUCTURE_TYPE_EXPORT_MEMORY_ALLOCATE_INFO };
 exportMemoryAllocateInfo.handleTypes = VK_EXTERNAL_MEMORY_HANDLE_TYPE_RDMA_ADDRESS_BIT_NV;
 
 // Find memory type index
 uint32_t i = 0;
 for (; i < VK_MAX_MEMORY_TYPES; i++) {
     if ((mem_reqs.memoryTypeBits & (1 << i)) &&
         (memoryProperties.memoryTypes[i].propertyFlags & VK_MEMORY_PROPERTY_RDMA_CAPABLE_BIT_NV)) {
         break;
     }
 }
 
 VkMemoryAllocateInfo memAllocInfo = { VK_STRUCTURE_TYPE_MEMORY_ALLOCATE_INFO, &exportMemoryAllocateInfo };
 memAllocInfo.allocationSize = mem_reqs.size;
 memAllocInfo.memoryTypeIndex = i;
 
 vkAllocateMemory(device, &memAllocInfo, NULL, &mem);
 vkBindBufferMemory(device, buffer, mem, 0);
 
 VkMemoryGetRemoteAddressInfoNV getMemoryRemoteAddressInfo = { VK_STRUCTURE_TYPE_MEMORY_GET_REMOTE_ADDRESS_INFO_NV };
 getMemoryRemoteAddressInfo.memory = mem;
 getMemoryRemoteAddressInfo.handleType = VK_EXTERNAL_MEMORY_HANDLE_TYPE_RDMA_ADDRESS_BIT_NV;
 
 VkRemoteAddressNV rdmaAddress;
 vkGetMemoryRemoteAddressNV(device, &getMemoryRemoteAddressInfo, &rdmaAddress);
 // address returned in 'rdmaAddress' can be used by external devices to initiate RDMA transfers

VK_NV_external_memory_rdma

Name String

VK_NV_external_memory_rdma

Extension Type

Device extension

Registered Extension Number

372

Revision

1

Extension and Version Dependencies

• Requires Vulkan 1.0
• Requires VK_KHR_external_memory

Contact

• Carsten Rohde crohde

Other Extension Metadata

Last Modified Date

2021-04-19

IP Status

No known IP claims.

Contributors

• Carsten Rohde, NVIDIA

Field Summary

Fields

Modifier and Type	Field	Description
static int	VK_EXTERNAL_MEMORY_HANDLE_TYPE_RDMA_ADDRESS_BIT_NV	Extends VkExternalMemoryHandleTypeFlagBits.
static int	VK_MEMORY_PROPERTY_RDMA_CAPABLE_BIT_NV	Extends VkMemoryPropertyFlagBits.
static java.lang.String	VK_NV_EXTERNAL_MEMORY_RDMA_EXTENSION_NAME	The extension name.
static int	VK_NV_EXTERNAL_MEMORY_RDMA_SPEC_VERSION	The extension specification version.
static int	VK_STRUCTURE_TYPE_MEMORY_GET_REMOTE_ADDRESS_INFO_NV VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_EXTERNAL_MEMORY_RDMA_FEATURES_NV	Extends VkStructureType.

Method Summary

Modifier and Type	Method	Description
static int	nvkGetMemoryRemoteAddressNV(org.lwjgl.vulkan.VkDevice device, long pMemoryGetRemoteAddressInfo, long pAddress)	Unsafe version of: GetMemoryRemoteAddressNV
static int	vkGetMemoryRemoteAddressNV(org.lwjgl.vulkan.VkDevice device, VkMemoryGetRemoteAddressInfoNV pMemoryGetRemoteAddressInfo, org.lwjgl.PointerBuffer pAddress)	Get an address for a memory object accessible by remote devices.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

VK_NV_EXTERNAL_MEMORY_RDMA_SPEC_VERSION

The extension specification version.

VK_NV_EXTERNAL_MEMORY_RDMA_EXTENSION_NAME

The extension name.

VK_STRUCTURE_TYPE_MEMORY_GET_REMOTE_ADDRESS_INFO_NV, VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_EXTERNAL_MEMORY_RDMA_FEATURES_NV

Extends VkStructureType.

Enum values:

• STRUCTURE_TYPE_MEMORY_GET_REMOTE_ADDRESS_INFO_NV
• STRUCTURE_TYPE_PHYSICAL_DEVICE_EXTERNAL_MEMORY_RDMA_FEATURES_NV

VK_MEMORY_PROPERTY_RDMA_CAPABLE_BIT_NV

Extends VkMemoryPropertyFlagBits.

VK_EXTERNAL_MEMORY_HANDLE_TYPE_RDMA_ADDRESS_BIT_NV

Extends VkExternalMemoryHandleTypeFlagBits.

Method Detail

nvkGetMemoryRemoteAddressNV

public static int nvkGetMemoryRemoteAddressNV(org.lwjgl.vulkan.VkDevice device,
                                              long pMemoryGetRemoteAddressInfo,
                                              long pAddress)

Unsafe version of: GetMemoryRemoteAddressNV

vkGetMemoryRemoteAddressNV

public static int vkGetMemoryRemoteAddressNV(org.lwjgl.vulkan.VkDevice device,
                                             VkMemoryGetRemoteAddressInfoNV pMemoryGetRemoteAddressInfo,
                                             org.lwjgl.PointerBuffer pAddress)

Get an address for a memory object accessible by remote devices.

C Specification

To export an address representing the payload of a Vulkan device memory object accessible by remote devices, call:

 VkResult vkGetMemoryRemoteAddressNV(
     VkDevice                                    device,
     const VkMemoryGetRemoteAddressInfoNV*       pMemoryGetRemoteAddressInfo,
     VkRemoteAddressNV*                          pAddress);

Description

More communication may be required between the kernel-mode drivers of the devices involved. This information is out of scope of this documentation and should be requested from the vendors of the devices.

Valid Usage (Implicit)

• device must be a valid VkDevice handle
• pMemoryGetRemoteAddressInfo must be a valid pointer to a valid VkMemoryGetRemoteAddressInfoNV structure
• pAddress must be a valid pointer to a VkRemoteAddressNV value

Return Codes

On success, this command returns

• SUCCESS

On failure, this command returns

• ERROR_INVALID_EXTERNAL_HANDLE

See Also

VkMemoryGetRemoteAddressInfoNV

Parameters:

device - the logical device that created the device memory being exported.

pMemoryGetRemoteAddressInfo - a pointer to a VkMemoryGetRemoteAddressInfoNV structure containing parameters of the export operation.

pAddress - will return the address representing the payload of the device memory object.