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

Jason Gunthorpe
2025-06-03T13:38:39Z

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