Re: [PATCH 05/12] mm: Remove remaining uses of PFN_DEV

[Jason Gunthorpe <jgg@ziepe.ca>]

On Thu, May 29, 2025 at 04:32:06PM +1000, Alistair Popple wrote:
> PFN_DEV was used by callers of dax_direct_access() to figure out if the
> returned PFN is associated with a page using pfn_t_has_page() or
> not. However all DAX PFNs now require an assoicated ZONE_DEVICE page so can
> assume a page exists.
> 
> Other users of PFN_DEV were setting it before calling
> vmf_insert_mixed(). This is unnecessary as it is no longer checked, instead
> relying on pfn_valid() to determine if there is an associated page or not.
> 
> Signed-off-by: Alistair Popple <apopple@nvidia.com>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> ---
>  drivers/gpu/drm/gma500/fbdev.c     |  2 +-
>  drivers/gpu/drm/omapdrm/omap_gem.c |  5 ++---
>  drivers/s390/block/dcssblk.c       |  3 +--
>  drivers/vfio/pci/vfio_pci_core.c   |  6 ++----
>  fs/cramfs/inode.c                  |  2 +-
>  include/linux/pfn_t.h              | 25 ++-----------------------
>  mm/memory.c                        |  4 ++--
>  7 files changed, 11 insertions(+), 36 deletions(-)

Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>

Jason