| # 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. |