[PATCH v4 0/3] drm/gpusvm, drm/pagemap, drm/xe: Restructure migration in preparation for multi-device

["Thomas Hellström" <thomas.hellstrom@linux.intel.com>]

This patchset modifies the migration part of drm_gpusvm to drm_pagemap and
adds a populate_mm() op to drm_pagemap.

The idea is that the device that receives a pagefault determines if it wants to
migrate content and to where. It then calls the populate_mm() method of relevant
drm_pagemap.

This functionality was mostly already in place, but hard-coded for xe only without
going through a pagemap op. Since we might be dealing with separate devices moving
forward, it also now becomes the responsibilit of the populate_mm() op to
grab any necessary local device runtime pm references and keep them held while
its pages are present in an mm (struct mm_struct).

On thing to decide here is whether the populate_mm() callback should sit on a
struct drm_pagemap for now while we sort multi-device usability out or whether
we should add it (or something equivalent) to struct dev_pagemap.

v2:
- Rebase.
v3:
- Documentation updates (CI, Matt Brost)
- Don't change TTM buffer object type for VRAM allocations (Matt Brost)
v4:
- Documentation Updates (Himal Ghimiray, Matt Brost)
- Add an assert (Matt Brost)

Matthew Brost (1):
  drm/gpusvm, drm/pagemap: Move migration functionality to drm_pagemap

Thomas Hellström (2):
  drm/pagemap: Add a populate_mm op
  drm/xe: Implement and use the drm_pagemap populate_mm op

 Documentation/gpu/rfc/gpusvm.rst     |  12 +-
 drivers/gpu/drm/Makefile             |   6 +-
 drivers/gpu/drm/drm_gpusvm.c         | 761 +-----------------------
 drivers/gpu/drm/drm_pagemap.c        | 838 +++++++++++++++++++++++++++
 drivers/gpu/drm/xe/Kconfig           |  10 +-
 drivers/gpu/drm/xe/xe_bo_types.h     |   2 +-
 drivers/gpu/drm/xe/xe_device_types.h |   2 +-
 drivers/gpu/drm/xe/xe_svm.c          | 125 ++--
 drivers/gpu/drm/xe/xe_svm.h          |  10 +-
 drivers/gpu/drm/xe/xe_tile.h         |  11 +
 drivers/gpu/drm/xe/xe_vm.c           |   2 +-
 include/drm/drm_gpusvm.h             |  96 ---
 include/drm/drm_pagemap.h            | 135 +++++
 13 files changed, 1098 insertions(+), 912 deletions(-)
 create mode 100644 drivers/gpu/drm/drm_pagemap.c

-- 
2.49.0