On Fri, Mar 26, 2021 at 06:55:01AM +0100, Christoph Hellwig wrote:

Hi all,

i915 has some reason to want to avoid the track_pfn_remap overhead in remap_pfn_range. Add a function to the core VM to do just that rather than reinventing the functionality poorly in the driver.

Note that the remap_io_sg path does get exercises when using Xorg on my Thinkpad X1, so this should be considered lightly tested, I've not managed to hit the remap_io_mapping path at all.

Changes since v1:

• create a io_mapping_map_user wrapper instead of exporting remap_pfn_range_notrack
• switch to plain remap_pfn_range for remap_sg as it does not use a pre-verified pgprot from an iomap

I'm burried under patches and stuff so no in-depth review. But from a quick scan lgtm. On the series:

Acked-by: Daniel Vetter daniel.vetter@ffwll.ch

I've seen it's landed already in some tree, maybe if you can add the acks ftr?

Cheers, Daniel

Diffstat: drivers/gpu/drm/i915/Kconfig | 1 drivers/gpu/drm/i915/gem/i915_gem_mman.c | 9 +- drivers/gpu/drm/i915/i915_drv.h | 3 drivers/gpu/drm/i915/i915_mm.c | 117 ++++++------------------------- include/linux/io-mapping.h | 3 include/linux/mm.h | 2 mm/Kconfig | 3 mm/Makefile | 1 mm/io-mapping.c | 29 +++++++ mm/memory.c | 51 ++++++++----- 10 files changed, 97 insertions(+), 122 deletions(-)