VkMemoryUnmapFlagBits(3)

# VkMemoryUnmapFlagBits(3) Manual Page

## Name

VkMemoryUnmapFlagBits - Bitmask specifying additional parameters of a memory unmap

## C Specification

Bits which can be set in VkMemoryUnmapInfo::`flags`, specifying additional properties of a memory unmap, are:

    // Provided by VK_VERSION_1_4
    typedef enum VkMemoryUnmapFlagBits {
      // Provided by VK_EXT_map_memory_placed
        VK_MEMORY_UNMAP_RESERVE_BIT_EXT = 0x00000001,
    } VkMemoryUnmapFlagBits;

    // Provided by VK_KHR_map_memory2
    // Equivalent to VkMemoryUnmapFlagBits
    typedef VkMemoryUnmapFlagBits VkMemoryUnmapFlagBitsKHR;

## Description

- VK_MEMORY_UNMAP_RESERVE_BIT_EXT requests that virtual address range currently occupied by the memory map remain reserved after the vkUnmapMemory2 call completes. Future system memory map operations or calls to vkMapMemory or vkMapMemory2 will not return addresses in that range unless the range has since been unreserved by the client or the mapping is explicitly placed in that range by calling vkMapMemory2 with VK_MEMORY_MAP_PLACED_BIT_EXT, or doing the system memory map equivalent. When VK_MEMORY_UNMAP_RESERVE_BIT_EXT is set, the memory unmap operation may fail, in which case the memory object will remain host mapped and vkUnmapMemory2 will return VK_ERROR_MEMORY_MAP_FAILED.

## See Also

VK_KHR_map_memory2, VK_VERSION_1_4, VkMemoryUnmapFlags

## Document Notes

For more information, see the Vulkan Specification.

This page is extracted from the Vulkan Specification. Fixes and changes should be made to the Specification, not directly.

## Copyright

Copyright 2014-2026 The Khronos Group Inc.

SPDX-License-Identifier: CC-BY-4.0