On 2021-05-14 8:00 a.m., Christoph Hellwig wrote:

On Thu, May 13, 2021 at 04:31:41PM -0600, Logan Gunthorpe wrote:

quoted

 17 files changed, 570 insertions(+), 290 deletions(-)

I'm a little worried about all this extra code for no new functionality
at all.

Yes, this series is really just prep work for allowing new
functionality. And a bunch of cleanup has been tacked onto it. It should
make adding P2PDMA in userspace a lot easier and I expect other P2PDMA
use cases will be better enabled by it.

A lot of people don't like the pci_p2pdma_map_sg() special case and
can't use it in their use case because it only accepts homogenous SGLs.
This series gets rid of the special case and allows it to be used more
generally.

Logan