[PATCH v13 0/5] DMA-BUF Heaps (destaging ION)

From: John Stultz
Date: Mon Oct 21 2019 - 15:03:16 EST

Lucky number 13! :)

Last week in v12 I had re-added some symbol exports to support
later patches I have pending to enable loading heaps from
modules. He reminded me that back around v3 (its been awhile!) I
had removed those exports due to concerns about the fact that we
don't support module removal.

So I'm respinning the patches, removing the exports again. I'll
submit a patch to re-add them in a later series enabling moduels
which can be reviewed indepently.

With that done, lets get on to the boilerplate!

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

New in v13:
* Re-remove symbol exports, per discussion with Brian. I'll
resubmit these separately in a later patch so they can be
independently reviewed


Cc: Laura Abbott <labbott@xxxxxxxxxx>
Cc: Benjamin Gaignard <benjamin.gaignard@xxxxxxxxxx>
Cc: Sumit Semwal <sumit.semwal@xxxxxxxxxx>
Cc: Liam Mark <lmark@xxxxxxxxxxxxxx>
Cc: Pratik Patel <pratikp@xxxxxxxxxxxxxx>
Cc: Brian Starkey <Brian.Starkey@xxxxxxx>
Cc: Vincent Donnefort <Vincent.Donnefort@xxxxxxx>
Cc: Sudipto Paul <Sudipto.Paul@xxxxxxx>
Cc: Andrew F. Davis <afd@xxxxxx>
Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx>
Cc: Chenbo Feng <fengc@xxxxxxxxxx>
Cc: Alistair Strachan <astrachan@xxxxxxxxxx>
Cc: Hridya Valsaraju <hridya@xxxxxxxxxx>
Cc: Hillf Danton <hdanton@xxxxxxxx>
Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx

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

drivers/dma-buf/Kconfig | 11 +
drivers/dma-buf/Makefile | 2 +
drivers/dma-buf/dma-heap.c | 269 ++++++++++++++++++
drivers/dma-buf/heaps/Kconfig | 14 +
drivers/dma-buf/heaps/Makefile | 4 +
drivers/dma-buf/heaps/cma_heap.c | 178 ++++++++++++
drivers/dma-buf/heaps/heap-helpers.c | 268 +++++++++++++++++
drivers/dma-buf/heaps/heap-helpers.h | 55 ++++
drivers/dma-buf/heaps/system_heap.c | 124 ++++++++
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 | 238 ++++++++++++++++
14 files changed, 1304 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