mbox series

[v6,0/5] DMA-BUF Heaps (destaging ION)

Message ID 20190624194908.121273-1-john.stultz@linaro.org (mailing list archive)
Headers show
Series DMA-BUF Heaps (destaging ION) | expand

Message

John Stultz June 24, 2019, 7:49 p.m. UTC
Here is 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
heap.

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:
  https://git.linaro.org/people/john.stultz/android-dev.git/log/?h=dev/dma-buf-heap

And the userspace changes here:
  https://android-review.googlesource.com/c/device/linaro/hikey/+/909436

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 for now, since any such
accounting should be implemented by dma-buf core or the heaps
themselves.


New in v6:
* Number of cleanups and error path fixes suggested by Brian Starkey,
  many thanks for his close review and suggestions!


Outstanding concerns:
* Need to better understand various secure heap implementations.
  Some concern that heap private flags will be needed, but its
  also possible that dma-buf heaps can't solve everyone's needs,
  in which case, a vendor's secure buffer driver can implement
  their own dma-buf exporter. So I'm not too worried here.

Thoughts and feedback would be greatly appreciated!

thanks
-john

Cc: Laura Abbott <labbott@redhat.com>
Cc: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Liam Mark <lmark@codeaurora.org>
Cc: Pratik Patel <pratikp@codeaurora.org>
Cc: Brian Starkey <Brian.Starkey@arm.com>
Cc: Vincent Donnefort <Vincent.Donnefort@arm.com>
Cc: Sudipto Paul <Sudipto.Paul@arm.com>
Cc: Andrew F. Davis <afd@ti.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Chenbo Feng <fengc@google.com>
Cc: Alistair Strachan <astrachan@google.com>
Cc: dri-devel@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                       |  10 +
 drivers/dma-buf/Makefile                      |   2 +
 drivers/dma-buf/dma-heap.c                    | 249 +++++++++++++++++
 drivers/dma-buf/heaps/Kconfig                 |  14 +
 drivers/dma-buf/heaps/Makefile                |   4 +
 drivers/dma-buf/heaps/cma_heap.c              | 169 +++++++++++
 drivers/dma-buf/heaps/heap-helpers.c          | 262 ++++++++++++++++++
 drivers/dma-buf/heaps/heap-helpers.h          |  54 ++++
 drivers/dma-buf/heaps/system_heap.c           | 121 ++++++++
 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      | 234 ++++++++++++++++
 14 files changed, 1260 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

Comments

Laura Abbott July 1, 2019, 9:45 p.m. UTC | #1
On 6/24/19 3:49 PM, John Stultz wrote:
> Here is 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.
> 

I've gotten bogged down with both work and personal tasks
so I haven't had a chance to look too closely but, once again,
I'm happy to see this continue to move forward.

> The patchset implements per-heap devices which can be opened
> directly and then an ioctl is used to allocate a dmabuf from the
> heap.
> 
> 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:
>    https://git.linaro.org/people/john.stultz/android-dev.git/log/?h=dev/dma-buf-heap
> 
> And the userspace changes here:
>    https://android-review.googlesource.com/c/device/linaro/hikey/+/909436
> 
> 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 for now, since any such
> accounting should be implemented by dma-buf core or the heaps
> themselves.
> 
> 
> New in v6:
> * Number of cleanups and error path fixes suggested by Brian Starkey,
>    many thanks for his close review and suggestions!
> 
> 
> Outstanding concerns:
> * Need to better understand various secure heap implementations.
>    Some concern that heap private flags will be needed, but its
>    also possible that dma-buf heaps can't solve everyone's needs,
>    in which case, a vendor's secure buffer driver can implement
>    their own dma-buf exporter. So I'm not too worried here.
> 

syzbot found a DoS with Ion which I ACKed a fix for.
https://lore.kernel.org/lkml/03763360-a7de-de87-eb90-ba7838143930@I-love.SAKURA.ne.jp/
This series doesn't have the page pooling so that particular bug may
not be applicable but given this is not the first time I've
seen Ion used as a DoS mechanism, it would be good to think about
putting in some basic checks.

Thanks,
Laura

> Thoughts and feedback would be greatly appreciated!
> 
> thanks
> -john
> 
> Cc: Laura Abbott <labbott@redhat.com>
> Cc: Benjamin Gaignard <benjamin.gaignard@linaro.org>
> Cc: Sumit Semwal <sumit.semwal@linaro.org>
> Cc: Liam Mark <lmark@codeaurora.org>
> Cc: Pratik Patel <pratikp@codeaurora.org>
> Cc: Brian Starkey <Brian.Starkey@arm.com>
> Cc: Vincent Donnefort <Vincent.Donnefort@arm.com>
> Cc: Sudipto Paul <Sudipto.Paul@arm.com>
> Cc: Andrew F. Davis <afd@ti.com>
> Cc: Christoph Hellwig <hch@infradead.org>
> Cc: Chenbo Feng <fengc@google.com>
> Cc: Alistair Strachan <astrachan@google.com>
> Cc: dri-devel@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                       |  10 +
>   drivers/dma-buf/Makefile                      |   2 +
>   drivers/dma-buf/dma-heap.c                    | 249 +++++++++++++++++
>   drivers/dma-buf/heaps/Kconfig                 |  14 +
>   drivers/dma-buf/heaps/Makefile                |   4 +
>   drivers/dma-buf/heaps/cma_heap.c              | 169 +++++++++++
>   drivers/dma-buf/heaps/heap-helpers.c          | 262 ++++++++++++++++++
>   drivers/dma-buf/heaps/heap-helpers.h          |  54 ++++
>   drivers/dma-buf/heaps/system_heap.c           | 121 ++++++++
>   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      | 234 ++++++++++++++++
>   14 files changed, 1260 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
>
John Stultz July 1, 2019, 9:55 p.m. UTC | #2
On Mon, Jul 1, 2019 at 2:45 PM Laura Abbott <labbott@redhat.com> wrote:
>
> On 6/24/19 3:49 PM, John Stultz wrote:
> > Here is 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.
> >
>
> I've gotten bogged down with both work and personal tasks
> so I haven't had a chance to look too closely but, once again,
> I'm happy to see this continue to move forward.
>
> > The patchset implements per-heap devices which can be opened
> > directly and then an ioctl is used to allocate a dmabuf from the
> > heap.
> >
> > 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:
> >    https://git.linaro.org/people/john.stultz/android-dev.git/log/?h=dev/dma-buf-heap
> >
> > And the userspace changes here:
> >    https://android-review.googlesource.com/c/device/linaro/hikey/+/909436
> >
> > 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 for now, since any such
> > accounting should be implemented by dma-buf core or the heaps
> > themselves.
> >
> >
> > New in v6:
> > * Number of cleanups and error path fixes suggested by Brian Starkey,
> >    many thanks for his close review and suggestions!
> >
> >
> > Outstanding concerns:
> > * Need to better understand various secure heap implementations.
> >    Some concern that heap private flags will be needed, but its
> >    also possible that dma-buf heaps can't solve everyone's needs,
> >    in which case, a vendor's secure buffer driver can implement
> >    their own dma-buf exporter. So I'm not too worried here.
> >
>
> syzbot found a DoS with Ion which I ACKed a fix for.
> https://lore.kernel.org/lkml/03763360-a7de-de87-eb90-ba7838143930@I-love.SAKURA.ne.jp/
> This series doesn't have the page pooling so that particular bug may
> not be applicable but given this is not the first time I've
> seen Ion used as a DoS mechanism, it would be good to think about
> putting in some basic checks.

Yea, there's no shrinker right now (and my WIP page pool
implementation steals the network core's pagepool, which is statically
sized).

But the check in the alloc code seems reasonable so I can add it to
what I have. Appreciate the suggestion!

thanks
-john