Re: [PATCH v9 00/13] Add dmabuf read/write via io_uring

[Jens Axboe]

On 10/6/26 7:42 PM, Pavel Begunkov wrote:
> The patch set allows to register a dmabuf to an io_uring instance for
> a specified file and use it with io_uring read / write requests. The
> infrastructure is not tied to io_uring and there could be more users
> in the future. A similar idea was attempted some years ago by Keith [1],
> from where I borrowed a number of changes. Later it was brough back up
> to life by Tushar and Vishal.
> 
> It's an opt-in feature for files, and they need to implement a new
> file operation to use it. Only NVMe block devices are supported in this
> series. The user API is built on top of io_uring's "registered buffers",
> where a dmabuf is registered in a special way, but after it can be used
> as any other "registered buffer" with IORING_OP_{READ,WRITE}_FIXED
> requests. It's created via a new file operation and the resulted map is
> then passed through the I/O stack in a new iterator type. There is some
> additional infrastructure to glue it together, count requests, manage
> lifetime and implement invalidation.

I've queued this series up for some testing, in a separate branch. JFYI.

-- 
Jens Axboe