Re: [PATCH v3 04/18] driver core: platform: Add driver dma ownership management

From: Jason Gunthorpe
Date: Mon Dec 06 2021 - 10:10:53 EST


On Mon, Dec 06, 2021 at 06:36:27AM -0800, Christoph Hellwig wrote:
> I really hate the amount of boilerplate code that having this in each
> bus type causes.

+1

I liked the first version of this series better with the code near
really_probe().

Can we go back to that with some device_configure_dma() wrapper
condtionally called by really_probe as we discussed?

> Between that and the suggestion from Joerg I wonder if we could do the
> following again:
>
> - add new no_kernel_dma flag to struct device_driver
> - set this flag for the various vfio drivers
> - skip claiming the kernel dma ownership for those (or rather release
> it if the suggestion from Joerg works out)

v1 did exactly this.

Jason