[PATCH v2 0/3] drm/gpusvm, drm/pagemap, drm/xe: Restructure migration in preparation for multi-device

[Christian König]

Hi Thomas,

please make sure to loop in Kuehling, Felix <Felix.Kuehling at amd.com> and Yang, Philip <Philip.Yang at amd.com> for that kind of stuff.

I'm absolutely not deep enough in the pagemap handling to judge any of that here.

Thanks,
Christian.

On 6/4/25 11:35, Thomas Hellström wrote:
> 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.
> 
> 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         | 760 +-----------------------
>  drivers/gpu/drm/drm_pagemap.c        | 846 +++++++++++++++++++++++++++
>  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          | 129 ++--
>  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, 1107 insertions(+), 914 deletions(-)
>  create mode 100644 drivers/gpu/drm/drm_pagemap.c
>