Re: [PATCH v3] fpga: dfl: afu: convert get_user_pages() --> pin_user_pages()

On Wed, May 27, 2020 at 12:10:21AM +, Wu, Hao wrote: > > -Original Message- > > From: John Hubbard > > Sent: Tuesday, May 26, 2020 6:18 AM > > To: LKML > > Cc: John Hubbard ; Xu, Yilun ; > > Wu, Hao ; Moritz Fischer ; linux- > > f...@vger.ke

RE: [PATCH v3] fpga: dfl: afu: convert get_user_pages() --> pin_user_pages()

> -Original Message- > From: John Hubbard > Sent: Tuesday, May 26, 2020 6:18 AM > To: LKML > Cc: John Hubbard ; Xu, Yilun ; > Wu, Hao ; Moritz Fischer ; linux- > f...@vger.kernel.org > Subject: [PATCH v3] fpga: dfl: afu: convert get_user_pages() --> > pin_u

[PATCH v3] fpga: dfl: afu: convert get_user_pages() --> pin_user_pages()

This code was using get_user_pages_fast(), in a "Case 2" scenario (DMA/RDMA), using the categorization from [1]. That means that it's time to convert the get_user_pages_fast() + put_page() calls to pin_user_pages_fast() + unpin_user_pages() calls. There is some helpful background in [2]: basically