summaryrefslogtreecommitdiff
path: root/dvalin/kernel/Documentation/dma-buf-test-exporter.txt
blob: b01020c0675188e69cb1350d9c7fe4f83e5faef5 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
# SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note
#
# (C) COPYRIGHT 2012-2013, 2020-2021 ARM Limited. All rights reserved.
#
# This program is free software and is provided to you under the terms of the
# GNU General Public License version 2 as published by the Free Software
# Foundation, and any use by you of this program is subject to the terms
# of such GNU license.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, you can access it online at
# http://www.gnu.org/licenses/gpl-2.0.html.
#
#

=====================
dma-buf-test-exporter
=====================

Overview
--------

The dma-buf-test-exporter is a simple exporter of dma_buf objects.
It has a private API to allocate and manipulate the buffers which are represented as dma_buf fds.
The private API allows:
* simple allocation of physically non-contiguous buffers
* simple allocation of physically contiguous buffers
* query kernel side API usage stats (number of attachments, number of mappings, mmaps)
* failure mode configuration (fail attach, mapping, mmap)
* kernel side memset of buffers

The buffers support all of the dma_buf API, including mmap.

It supports being compiled as a module both in-tree and out-of-tree.

See include/linux/dma-buf-test-exporter.h for the ioctl interface.
See Documentation/dma-buf-sharing.txt for details on dma_buf.