[PATCH v8 0/5] DMA-BUF Heaps (destaging ION)

John Stultz john.stultz at linaro.org
Fri Aug 23 23:47:42 UTC 2019

Here is yet another pass at the dma-buf heaps patchset Andrew
and I have been working on which tries to destage a fair chunk
of ION functionality.

The patchset implements per-heap devices which can be opened
directly and then an ioctl is used to allocate a dmabuf from the

The interface is similar, but much simpler then IONs, only
providing an ALLOC ioctl.

Also, I've provided relatively simple system and cma heaps.

I've booted and tested these patches with AOSP on the HiKey960
using the kernel tree here:

And the userspace changes here:

Compared to ION, this patchset is missing the system-contig,
carveout and chunk heaps, as I don't have a device that uses
those, so I'm unable to do much useful validation there.
Additionally we have no upstream users of chunk or carveout,
and the system-contig has been deprecated in the common/andoid-*
kernels, so this should be ok.

I've also removed the stats accounting, since any such accounting
should be implemented by dma-buf core or the heaps themselves.

Most of the changes in this revision are adddressing the more
concrete feedback from Christoph (many thanks!). Though I'm not
sure if some of the less specific feedback was completely resolved
in discussion last time around. Please let me know!

New in v8:
* Make struct dma_heap_ops consts (Suggested by Christoph)
* Add flush_kernel_vmap_range/invalidate_kernel_vmap_range calls
  (suggested by Christoph)
* Condense dma_heap_buffer and heap_helper_buffer (suggested by
* Get rid of needless struct system_heap (suggested by Christoph)
* Fix indentation by using shorter argument names (suggested by
* Remove unused private_flags value
* Add forgotten include file to fix build issue on x86
* Checkpatch whitespace fixups

Thoughts and feedback would be greatly appreciated!


Cc: Laura Abbott <labbott at redhat.com>
Cc: Benjamin Gaignard <benjamin.gaignard at linaro.org>
Cc: Sumit Semwal <sumit.semwal at linaro.org>
Cc: Liam Mark <lmark at codeaurora.org>
Cc: Pratik Patel <pratikp at codeaurora.org>
Cc: Brian Starkey <Brian.Starkey at arm.com>
Cc: Vincent Donnefort <Vincent.Donnefort at arm.com>
Cc: Sudipto Paul <Sudipto.Paul at arm.com>
Cc: Andrew F. Davis <afd at ti.com>
Cc: Christoph Hellwig <hch at infradead.org>
Cc: Chenbo Feng <fengc at google.com>
Cc: Alistair Strachan <astrachan at google.com>
Cc: Hridya Valsaraju <hridya at google.com>
Cc: dri-devel at lists.freedesktop.org

Andrew F. Davis (1):
  dma-buf: Add dma-buf heaps framework

John Stultz (4):
  dma-buf: heaps: Add heap helpers
  dma-buf: heaps: Add system heap to dmabuf heaps
  dma-buf: heaps: Add CMA heap to dmabuf heaps
  kselftests: Add dma-heap test

 MAINTAINERS                                   |  18 ++
 drivers/dma-buf/Kconfig                       |  11 +
 drivers/dma-buf/Makefile                      |   2 +
 drivers/dma-buf/dma-heap.c                    | 250 ++++++++++++++++
 drivers/dma-buf/heaps/Kconfig                 |  14 +
 drivers/dma-buf/heaps/Makefile                |   4 +
 drivers/dma-buf/heaps/cma_heap.c              | 164 +++++++++++
 drivers/dma-buf/heaps/heap-helpers.c          | 269 ++++++++++++++++++
 drivers/dma-buf/heaps/heap-helpers.h          |  55 ++++
 drivers/dma-buf/heaps/system_heap.c           | 122 ++++++++
 include/linux/dma-heap.h                      |  59 ++++
 include/uapi/linux/dma-heap.h                 |  55 ++++
 tools/testing/selftests/dmabuf-heaps/Makefile |   9 +
 .../selftests/dmabuf-heaps/dmabuf-heap.c      | 230 +++++++++++++++
 14 files changed, 1262 insertions(+)
 create mode 100644 drivers/dma-buf/dma-heap.c
 create mode 100644 drivers/dma-buf/heaps/Kconfig
 create mode 100644 drivers/dma-buf/heaps/Makefile
 create mode 100644 drivers/dma-buf/heaps/cma_heap.c
 create mode 100644 drivers/dma-buf/heaps/heap-helpers.c
 create mode 100644 drivers/dma-buf/heaps/heap-helpers.h
 create mode 100644 drivers/dma-buf/heaps/system_heap.c
 create mode 100644 include/linux/dma-heap.h
 create mode 100644 include/uapi/linux/dma-heap.h
 create mode 100644 tools/testing/selftests/dmabuf-heaps/Makefile
 create mode 100644 tools/testing/selftests/dmabuf-heaps/dmabuf-heap.c


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