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

[Sumit Semwal]

Hi John,

On Tue, 22 Oct 2019 at 00:33, John Stultz <john.stultz@xxxxxxxxxx> wrote:
>
> 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.

This looks good to me, and hasn't seen any more comments, so I am
going to merge it via drm-misc-next today.
>
> 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
> 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, since any such
> accounting should be implemented by dma-buf core or the heaps
> themselves.
>
> 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
>
> thanks
> -john

<snip>

Best,
Sumit.