1# SPDX-License-Identifier: GPL-2.0-only
2menu "DMABUF options"
3
4config SYNC_FILE
5	bool "Explicit Synchronization Framework"
6	default n
7	select DMA_SHARED_BUFFER
8	help
9	  The Sync File Framework adds explicit synchronization via
10	  userspace. It enables send/receive 'struct dma_fence' objects to/from
11	  userspace via Sync File fds for synchronization between drivers via
12	  userspace components. It has been ported from Android.
13
14	  The first and main user for this is graphics in which a fence is
15	  associated with a buffer. When a job is submitted to the GPU a fence
16	  is attached to the buffer and is transferred via userspace, using Sync
17	  Files fds, to the DRM driver for example. More details at
18	  Documentation/driver-api/sync_file.rst.
19
20config SW_SYNC
21	bool "Sync File Validation Framework"
22	default n
23	depends on SYNC_FILE
24	depends on DEBUG_FS
25	help
26	  A sync object driver that uses a 32bit counter to coordinate
27	  synchronization.  Useful when there is no hardware primitive backing
28	  the synchronization.
29
30	  WARNING: improper use of this can result in deadlocking kernel
31	  drivers from userspace. Intended for test and debug only.
32
33config UDMABUF
34	bool "userspace dmabuf misc driver"
35	default n
36	depends on DMA_SHARED_BUFFER
37	depends on MEMFD_CREATE || COMPILE_TEST
38	help
39	  A driver to let userspace turn memfd regions into dma-bufs.
40	  Qemu can use this to create host dmabufs for guest framebuffers.
41
42config DMABUF_MOVE_NOTIFY
43	bool "Move notify between drivers (EXPERIMENTAL)"
44	default n
45	depends on DMA_SHARED_BUFFER
46	help
47	  Don't pin buffers if the dynamic DMA-buf interface is available on
48	  both the exporter as well as the importer. This fixes a security
49	  problem where userspace is able to pin unrestricted amounts of memory
50	  through DMA-buf.
51	  This is marked experimental because we don't yet have a consistent
52	  execution context and memory management between drivers.
53
54config DMABUF_DEBUG
55	bool "DMA-BUF debug checks"
56	depends on DMA_SHARED_BUFFER
57	default y if DMA_API_DEBUG
58	help
59	  This option enables additional checks for DMA-BUF importers and
60	  exporters. Specifically it validates that importers do not peek at the
61	  underlying struct page when they import a buffer.
62
63config DMABUF_SELFTESTS
64	tristate "Selftests for the dma-buf interfaces"
65	default n
66	depends on DMA_SHARED_BUFFER
67
68menuconfig DMABUF_HEAPS
69	bool "DMA-BUF Userland Memory Heaps"
70	select DMA_SHARED_BUFFER
71	help
72	  Choose this option to enable the DMA-BUF userland memory heaps.
73	  This options creates per heap chardevs in /dev/dma_heap/ which
74	  allows userspace to allocate dma-bufs that can be shared
75	  between drivers.
76
77menuconfig DMABUF_SYSFS_STATS
78	bool "DMA-BUF sysfs statistics (DEPRECATED)"
79	depends on DMA_SHARED_BUFFER
80	help
81	   Choose this option to enable DMA-BUF sysfs statistics
82	   in location /sys/kernel/dmabuf/buffers.
83
84	   /sys/kernel/dmabuf/buffers/<inode_number> will contain
85	   statistics for the DMA-BUF with the unique inode number
86	   <inode_number>.
87
88	   This option is deprecated and should sooner or later be removed.
89	   Android is the only user of this and it turned out that this resulted
90	   in quite some performance problems.
91
92source "drivers/dma-buf/heaps/Kconfig"
93
94endmenu
95