Re: start sorting out the ZONE_DEVICE refcount mess

[Logan Gunthorpe <logang@deltatee.com>]

On 2022-02-06 11:32 p.m., Christoph Hellwig wrote:
> Hi all,
> 
> this series removes the offset by one refcount for ZONE_DEVICE pages
> that are freed back to the driver owning them, which is just device
> private ones for now, but also the planned device coherent pages
> and the ehanced p2p ones pending.
> 
> It does not address the fsdax pages yet, which will be attacked in a
> follow on series.
> 
> Diffstat:
>  arch/arm64/mm/mmu.c                      |    1 
>  arch/powerpc/kvm/book3s_hv_uvmem.c       |    1 
>  drivers/gpu/drm/amd/amdkfd/kfd_migrate.c |    2 
>  drivers/gpu/drm/amd/amdkfd/kfd_priv.h    |    1 
>  drivers/gpu/drm/drm_cache.c              |    2 
>  drivers/gpu/drm/nouveau/nouveau_dmem.c   |    3 -
>  drivers/gpu/drm/nouveau/nouveau_svm.c    |    1 
>  drivers/infiniband/core/rw.c             |    1 
>  drivers/nvdimm/pmem.h                    |    1 
>  drivers/nvme/host/pci.c                  |    1 
>  drivers/nvme/target/io-cmd-bdev.c        |    1 
>  fs/Kconfig                               |    2 
>  fs/fuse/virtio_fs.c                      |    1 
>  include/linux/hmm.h                      |    9 ----
>  include/linux/memremap.h                 |   22 +++++++++-
>  include/linux/mm.h                       |   59 ++++-------------------------
>  lib/test_hmm.c                           |    4 +
>  mm/Kconfig                               |    4 -
>  mm/internal.h                            |    2 
>  mm/memcontrol.c                          |   11 +----
>  mm/memremap.c                            |   63 ++++++++++++++++---------------
>  mm/migrate.c                             |    6 --
>  mm/swap.c                                |   49 ++----------------------
>  23 files changed, 90 insertions(+), 157 deletions(-)

Looks good to me. I was wondering about the location of some of this
code, so it's nice to see it cleaned up. Except for the one minor issue
I noted on patch 6, it all looks good to me. I've reviewed all the
patches and tested the series under my p2pdma series.

Reviewed-by: Logan Gunthorpe <logang@deltatee.com>

Logan