swh:1:snp:49cd9498d6cccc5e78252c27dcb645bcf7bf0c91
Tip revision: bbf5c979011a099af5dc76498918ed7df445635b authored by Linus Torvalds on 11 October 2020, 21:15:50 UTC
Linux 5.9
Linux 5.9
Tip revision: bbf5c97
Kconfig
# SPDX-License-Identifier: GPL-2.0-only
menu "DMABUF options"
config SYNC_FILE
bool "Explicit Synchronization Framework"
default n
select DMA_SHARED_BUFFER
help
The Sync File Framework adds explicit synchronization via
userspace. It enables send/receive 'struct dma_fence' objects to/from
userspace via Sync File fds for synchronization between drivers via
userspace components. It has been ported from Android.
The first and main user for this is graphics in which a fence is
associated with a buffer. When a job is submitted to the GPU a fence
is attached to the buffer and is transferred via userspace, using Sync
Files fds, to the DRM driver for example. More details at
Documentation/driver-api/sync_file.rst.
config SW_SYNC
bool "Sync File Validation Framework"
default n
depends on SYNC_FILE
depends on DEBUG_FS
help
A sync object driver that uses a 32bit counter to coordinate
synchronization. Useful when there is no hardware primitive backing
the synchronization.
WARNING: improper use of this can result in deadlocking kernel
drivers from userspace. Intended for test and debug only.
config UDMABUF
bool "userspace dmabuf misc driver"
default n
depends on DMA_SHARED_BUFFER
depends on MEMFD_CREATE || COMPILE_TEST
help
A driver to let userspace turn memfd regions into dma-bufs.
Qemu can use this to create host dmabufs for guest framebuffers.
config DMABUF_MOVE_NOTIFY
bool "Move notify between drivers (EXPERIMENTAL)"
default n
help
Don't pin buffers if the dynamic DMA-buf interface is available on
both the exporter as well as the importer. This fixes a security
problem where userspace is able to pin unrestricted amounts of memory
through DMA-buf.
This is marked experimental because we don't yet have a consistent
execution context and memory management between drivers.
config DMABUF_SELFTESTS
tristate "Selftests for the dma-buf interfaces"
default n
depends on DMA_SHARED_BUFFER
menuconfig DMABUF_HEAPS
bool "DMA-BUF Userland Memory Heaps"
select DMA_SHARED_BUFFER
help
Choose this option to enable the DMA-BUF userland memory heaps.
This options creates per heap chardevs in /dev/dma_heap/ which
allows userspace to allocate dma-bufs that can be shared
between drivers.
source "drivers/dma-buf/heaps/Kconfig"
endmenu