This CL adds a Posix-based implementation for the VK_KHR_external_memory_fd Vulkan extension, using the SysV shm_open() / shm_unlink() API to create the shared memory region. The Linux backend still uses memfd-based regions which are easier to create, and because Android does not provide shm_open() intentionally [1]. [1] https://android.googlesource.com/platform/ndk/+/4e159d95ebf23b5f72bb707b0cb1518ef96b3d03/docs/system/libc/SYSV-IPC.TXT Bug: b/140419396 Tests: dEQP-VK.* Change-Id: Ibbb23c3af59e81f76e41a0e71281f6d1a8b07c01 Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/41408Reviewed-by: Nicolas Capens <nicolascapens@google.com> Tested-by: Yilong Li <liyl@google.com> Commit-Queue: Nicolas Capens <nicolascapens@google.com> Kokoro-Result: kokoro <noreply+kokoro@google.com>
