On 7/7/25 22:55, Mina Almasry wrote:

On Mon, Jul 7, 2025 at 2:35 PM Dragos Tatulea [off-list ref] wrote:

...>> Right. My patches show that. But the issue raised by Parav is different:

quoted

different queues can belong to different DMA devices from different
PFs in the case of Multi PF netdev.

io_uring can do it because it maps individual buffers to individual
queues. So it would be trivial to get the DMA device of each queue through
a new queue op.

Right, devmem doesn't stop you from mapping individual buffers to
individual queues. It just also supports mapping the same buffer to
multiple queues. AFAIR, io_uring also supports mapping a single buffer
to multiple queues, but I could easily be very wrong about that. It's

It doesn't, but it could benefit from sharing depending on userspace,
so it might eventually come to the same problem.

-- 
Pavel Begunkov