[RFC PATCH v2 0/8] Support DEVICE_GENERIC memory in migrate_vma_*

[Alex Sierra]

v1:
https://lore.kernel.org/linux-mm/20210529064022.GB15834@lst.de/T/

v2:
This patch series version has merged "[RFC PATCH v3 0/2]
mm: remove extra ZONE_DEVICE struct page refcount" patch series made by
Ralph Campbell. It also applies at the top of these series, our changes
to support device generic type in migration_vma helpers.
This has been tested in systems with device memory that has coherent
access by CPU.

Also addresses the following feedback made in v1:
- Isolate in one patch kernel/resource.c modification, based
on Christoph's feedback.
- Add helpers check for generic and private type to avoid
duplicated long lines.

I like to provide an overview of what each of the patches does in a series:

Patches 1-2: Rebased Ralph Campbell's ZONE_DEVICE page refcounting patches
Patch 3: Export lookup_resource
Patches 4-5: AMDGPU driver changes to register and use DEVICE_GENERIC memory
Patches 6-8: Handle DEVICE_GENERIC memory in migration helpers

Alex Sierra (6):
  kernel: resource: lookup_resource as exported symbol
  drm/amdkfd: add SPM support for SVM
  drm/amdkfd: generic type as sys mem on migration to ram
  include/linux/mm.h: helpers to check zone device generic type
  mm: add generic type support to migrate_vma helpers
  mm: call pgmap->ops->page_free for DEVICE_GENERIC pages

Ralph Campbell (2):
  ext4/xfs: add page refcount helper
  mm: remove extra ZONE_DEVICE struct page refcount

 arch/powerpc/kvm/book3s_hv_uvmem.c       |  2 +-
 drivers/gpu/drm/amd/amdkfd/kfd_migrate.c | 15 ++++--
 drivers/gpu/drm/nouveau/nouveau_dmem.c   |  2 +-
 fs/dax.c                                 |  8 +--
 fs/ext4/inode.c                          |  5 +-
 fs/xfs/xfs_file.c                        |  4 +-
 include/linux/dax.h                      | 10 ++++
 include/linux/memremap.h                 |  7 +--
 include/linux/mm.h                       | 52 +++---------------
 kernel/resource.c                        |  2 +-
 lib/test_hmm.c                           |  2 +-
 mm/internal.h                            |  8 +++
 mm/memremap.c                            | 69 +++++++-----------------
 mm/migrate.c                             | 13 ++---
 mm/page_alloc.c                          |  3 ++
 mm/swap.c                                | 45 ++--------------
 16 files changed, 83 insertions(+), 164 deletions(-)

-- 
2.17.1