[Week 4] Import the Xen grant-table bus_dma(9) handlers from OpenBSD

[Akshay Jaggi]

Hi Pratyush,

On Mon, 11 Jun 2018 at 12:48, Pratyush Yadav <pratyush at freebsd.org> wrote:

> Hi,
>
> This week I finished up my implementation of the xen-specific
> bus_dma(9) handlers. I asked Roger Pau Monne for review. After his
> review, I realized I had been doing things a little wrong. I was
> building the Xen-specific handlers on top of the bus_dma(9) interface.
> Instead, I should have created an alternate busdma implementation,
> kind of like sys/x86/iommu/busdma_dmar.c
>
> So I had to study the inner details of the bus_dma(9) interface to
> learn how an alternate implementation can be written. This was a
> little confusing at the beginning.because there is no clear guide on
> the subsystem for beginners like me. But eventually, I got the hang of
> it, mostly by reading code already written.
>
>
This is really good work. :)


> After that came the task of rewriting my implementation. I wrote it,
> and then spent a couple of days refining it. Today, I submitted it to
> Roger again for review. We are discussing it as of now. No major
> concerns have been raised so I should be done with the xen-specific
> busdma hooks in a few days.
>
> You can check out the code at [0].
>

Since Roger is already reviewing the code, you are in good hands. I've
nitpicked on few small style and consistency issues.

Regards,
Akshay


>
> I maintain a blog on Blogger where I publish my progress every few
> days. Check it out if you want more details on what I'm doing [1].
>
>
> [0] https://github.com/prati0100/freebsd
>
> [1]
> http://pratyushgsoc.blogspot.in/2018/05/import-xen-grant-table-busdma9-handlers.html
>
> --
> Regards,
> Pratyush Yadav
>