[RFC 0/4] mm: Remove pfn_t type

[RFC 0/4] mm: Remove pfn_t type

[Alistair Popple]

Once my series[1] and Dan's cleanup[2] is merged all users of DAX will
require a ZONE_DEVICE page which is properly refcounted.  This means there
is no longer any need for the PFN_DEV and PFN_MAP flags. Furthermore the
PFN_SG_CHAIN and PFN_SG_LAST flags never appear to have been used. It is
therefore possible to remove the pfn_t type and replace any usage with raw
pfns.

The remaining users of PFN_DEV have simply passed this to
vmf_insert_mixed(), however once my series is merged vmf_insert_mixed()
doesn't need these flags anyway so those users can be trivially converted
to using raw pfns.

Note that this RFC has only been lightly build tested. Also the third patch
probably needs further splitting up. I have pushed a tree with this, along
with the prerequisite series, to
https://github.com/apopple/linux/tree/pfn_t_cleanup

[1] - https://lore.kernel.org/linux-mm/cover.425da7c4e76c2749d0ad1734f972b06114e02d52.1736221254.git-series.apopple@nvidia.com/
[2] - https://lore.kernel.org/linux-mm/172721874675.497781.3277495908107141898.stgit@dwillia2-xfh.jf.intel.com/

---

Cc: gerald.schaefer@linux.ibm.com
Cc: dan.j.williams@intel.com
Cc: jgg@ziepe.ca
Cc: willy@infradead.org
Cc: david@redhat.com
Cc: linux-kernel@vger.kernel.org
Cc: nvdimm@lists.linux.dev
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: linux-ext4@vger.kernel.org
Cc: linux-xfs@vger.kernel.org
Cc: jhubbard@nvidia.com
Cc: hch@lst.de

Alistair Popple (4):
  mm: Remove PFN_MAP, PFN_SG_CHAIN and PFN_SG_LAST
  mm: Remove uses of PFN_DEV
  mm: Remove callers of pfn_t functionality
  mm: Remove include/linux/pfn_t.h

 arch/x86/mm/pat/memtype.c                |  6 +-
 drivers/dax/device.c                     | 23 ++----
 drivers/dax/hmem/hmem.c                  |  1 +-
 drivers/dax/kmem.c                       |  1 +-
 drivers/dax/pmem.c                       |  1 +-
 drivers/dax/super.c                      |  3 +-
 drivers/gpu/drm/exynos/exynos_drm_gem.c  |  1 +-
 drivers/gpu/drm/gma500/fbdev.c           |  3 +-
 drivers/gpu/drm/i915/gem/i915_gem_mman.c |  1 +-
 drivers/gpu/drm/msm/msm_gem.c            |  1 +-
 drivers/gpu/drm/omapdrm/omap_gem.c       |  7 +--
 drivers/gpu/drm/v3d/v3d_bo.c             |  1 +-
 drivers/md/dm-linear.c                   |  2 +-
 drivers/md/dm-log-writes.c               |  2 +-
 drivers/md/dm-stripe.c                   |  2 +-
 drivers/md/dm-target.c                   |  2 +-
 drivers/md/dm-writecache.c               |  9 +--
 drivers/md/dm.c                          |  2 +-
 drivers/nvdimm/pmem.c                    |  8 +--
 drivers/nvdimm/pmem.h                    |  4 +-
 drivers/s390/block/dcssblk.c             | 10 +--
 drivers/vfio/pci/vfio_pci_core.c         |  7 +--
 fs/cramfs/inode.c                        |  4 +-
 fs/dax.c                                 | 45 +++++-------
 fs/ext4/file.c                           |  2 +-
 fs/fuse/dax.c                            |  3 +-
 fs/fuse/virtio_fs.c                      |  5 +-
 fs/xfs/xfs_file.c                        |  2 +-
 include/linux/dax.h                      |  8 +-
 include/linux/device-mapper.h            |  2 +-
 include/linux/huge_mm.h                  |  4 +-
 include/linux/mm.h                       |  4 +-
 include/linux/pfn.h                      | 10 +---
 include/linux/pfn_t.h                    | 96 +-------------------------
 include/linux/pgtable.h                  |  4 +-
 include/trace/events/fs_dax.h            |  6 +--
 mm/debug_vm_pgtable.c                    |  1 +-
 mm/huge_memory.c                         | 23 +++---
 mm/memory.c                              | 32 +++-----
 mm/memremap.c                            |  1 +-
 mm/migrate.c                             |  1 +-
 tools/testing/nvdimm/pmem-dax.c          |  6 +-
 tools/testing/nvdimm/test/iomap.c        | 11 +---
 43 files changed, 108 insertions(+), 259 deletions(-)
 delete mode 100644 include/linux/pfn_t.h

base-commit: 47dc3422e9f51a38e4d5490937f798f080015756
-- 
git-series 0.9.1

[RFC 1/4] mm: Remove PFN_MAP, PFN_SG_CHAIN and PFN_SG_LAST

[Alistair Popple]

The PFN_MAP flag is no longer used for anything, so remove it. The
PFN_SG_CHAIN and PFN_SG_LAST flags never appear to have been used so
also remove them.

Signed-off-by: Alistair Popple <apopple@nvidia.com>
---
 include/linux/pfn_t.h             | 10 ++--------
 tools/testing/nvdimm/test/iomap.c |  4 ----
 2 files changed, 2 insertions(+), 12 deletions(-)

diff --git a/include/linux/pfn_t.h b/include/linux/pfn_t.h
index 76e519b..75bb77c 100644
--- a/include/linux/pfn_t.h
+++ b/include/linux/pfn_t.h
@@ -11,16 +11,10 @@
  * PFN_MAP - pfn has a dynamic page mapping established by a device driver
  */
 #define PFN_FLAGS_MASK (((u64) (~PAGE_MASK)) << (BITS_PER_LONG_LONG - PAGE_SHIFT))
-#define PFN_SG_CHAIN (1ULL << (BITS_PER_LONG_LONG - 1))
-#define PFN_SG_LAST (1ULL << (BITS_PER_LONG_LONG - 2))
 #define PFN_DEV (1ULL << (BITS_PER_LONG_LONG - 3))
-#define PFN_MAP (1ULL << (BITS_PER_LONG_LONG - 4))
 
 #define PFN_FLAGS_TRACE \
-	{ PFN_SG_CHAIN,	"SG_CHAIN" }, \
-	{ PFN_SG_LAST,	"SG_LAST" }, \
-	{ PFN_DEV,	"DEV" }, \
-	{ PFN_MAP,	"MAP" }
+	{ PFN_DEV,	"DEV" }
 
 static inline pfn_t __pfn_to_pfn_t(unsigned long pfn, u64 flags)
 {
@@ -42,7 +36,7 @@ static inline pfn_t phys_to_pfn_t(phys_addr_t addr, u64 flags)
 
 static inline bool pfn_t_has_page(pfn_t pfn)
 {
-	return (pfn.val & PFN_MAP) == PFN_MAP || (pfn.val & PFN_DEV) == 0;
+	return (pfn.val & PFN_DEV) == 0;
 }
 
 static inline unsigned long pfn_t_to_pfn(pfn_t pfn)
diff --git a/tools/testing/nvdimm/test/iomap.c b/tools/testing/nvdimm/test/iomap.c
index e431372..ddceb04 100644
--- a/tools/testing/nvdimm/test/iomap.c
+++ b/tools/testing/nvdimm/test/iomap.c
@@ -137,10 +137,6 @@ EXPORT_SYMBOL_GPL(__wrap_devm_memremap_pages);
 
 pfn_t __wrap_phys_to_pfn_t(phys_addr_t addr, unsigned long flags)
 {
-	struct nfit_test_resource *nfit_res = get_nfit_res(addr);
-
-	if (nfit_res)
-		flags &= ~PFN_MAP;
         return phys_to_pfn_t(addr, flags);
 }
 EXPORT_SYMBOL(__wrap_phys_to_pfn_t);
-- 
git-series 0.9.1

[RFC 2/4] mm: Remove uses of PFN_DEV

[Alistair Popple]

PFN_DEV is used by callers of dax_direct_access() to figure out if the
returned PFN is associated with a 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>
---
 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              | 4 +---
 mm/memory.c                        | 4 ++--
 7 files changed, 10 insertions(+), 16 deletions(-)

diff --git a/drivers/gpu/drm/gma500/fbdev.c b/drivers/gpu/drm/gma500/fbdev.c
index 8edefea..109efdc 100644
--- a/drivers/gpu/drm/gma500/fbdev.c
+++ b/drivers/gpu/drm/gma500/fbdev.c
@@ -33,7 +33,7 @@ static vm_fault_t psb_fbdev_vm_fault(struct vm_fault *vmf)
 	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 
 	for (i = 0; i < page_num; ++i) {
-		err = vmf_insert_mixed(vma, address, __pfn_to_pfn_t(pfn, PFN_DEV));
+		err = vmf_insert_mixed(vma, address, __pfn_to_pfn_t(pfn, 0));
 		if (unlikely(err & VM_FAULT_ERROR))
 			break;
 		address += PAGE_SIZE;
diff --git a/drivers/gpu/drm/omapdrm/omap_gem.c b/drivers/gpu/drm/omapdrm/omap_gem.c
index b9c67e4..9df05b2 100644
--- a/drivers/gpu/drm/omapdrm/omap_gem.c
+++ b/drivers/gpu/drm/omapdrm/omap_gem.c
@@ -371,8 +371,7 @@ static vm_fault_t omap_gem_fault_1d(struct drm_gem_object *obj,
 	VERB("Inserting %p pfn %lx, pa %lx", (void *)vmf->address,
 			pfn, pfn << PAGE_SHIFT);
 
-	return vmf_insert_mixed(vma, vmf->address,
-			__pfn_to_pfn_t(pfn, PFN_DEV));
+	return vmf_insert_mixed(vma, vmf->address, __pfn_to_pfn_t(pfn, 0));
 }
 
 /* Special handling for the case of faulting in 2d tiled buffers */
@@ -468,7 +467,7 @@ static vm_fault_t omap_gem_fault_2d(struct drm_gem_object *obj,
 
 	for (i = n; i > 0; i--) {
 		ret = vmf_insert_mixed(vma,
-			vaddr, __pfn_to_pfn_t(pfn, PFN_DEV));
+			vaddr, __pfn_to_pfn_t(pfn, 0));
 		if (ret & VM_FAULT_ERROR)
 			break;
 		pfn += priv->usergart[fmt].stride_pfn;
diff --git a/drivers/s390/block/dcssblk.c b/drivers/s390/block/dcssblk.c
index 1ffc86e..8a0d590 100644
--- a/drivers/s390/block/dcssblk.c
+++ b/drivers/s390/block/dcssblk.c
@@ -924,8 +924,7 @@ __dcssblk_direct_access(struct dcssblk_dev_info *dev_info, pgoff_t pgoff,
 	if (kaddr)
 		*kaddr = __va(dev_info->start + offset);
 	if (pfn)
-		*pfn = __pfn_to_pfn_t(PFN_DOWN(dev_info->start + offset),
-				      PFN_DEV);
+		*pfn = __pfn_to_pfn_t(PFN_DOWN(dev_info->start + offset), 0);
 
 	return (dev_sz - offset) / PAGE_SIZE;
 }
diff --git a/drivers/vfio/pci/vfio_pci_core.c b/drivers/vfio/pci/vfio_pci_core.c
index 90240c8..e6b6c01 100644
--- a/drivers/vfio/pci/vfio_pci_core.c
+++ b/drivers/vfio/pci/vfio_pci_core.c
@@ -1680,14 +1680,12 @@ static vm_fault_t vfio_pci_mmap_huge_fault(struct vm_fault *vmf,
 		break;
 #ifdef CONFIG_ARCH_SUPPORTS_PMD_PFNMAP
 	case PMD_ORDER:
-		ret = vmf_insert_pfn_pmd(vmf, __pfn_to_pfn_t(pfn + pgoff,
-							     PFN_DEV), false);
+		ret = vmf_insert_pfn_pmd(vmf, __pfn_to_pfn_t(pfn + pgoff, 0), false);
 		break;
 #endif
 #ifdef CONFIG_ARCH_SUPPORTS_PUD_PFNMAP
 	case PUD_ORDER:
-		ret = vmf_insert_pfn_pud(vmf, __pfn_to_pfn_t(pfn + pgoff,
-							     PFN_DEV), false);
+		ret = vmf_insert_pfn_pud(vmf, __pfn_to_pfn_t(pfn + pgoff, 0), false);
 		break;
 #endif
 	default:
diff --git a/fs/cramfs/inode.c b/fs/cramfs/inode.c
index b84d174..820a664 100644
--- a/fs/cramfs/inode.c
+++ b/fs/cramfs/inode.c
@@ -412,7 +412,7 @@ static int cramfs_physmem_mmap(struct file *file, struct vm_area_struct *vma)
 		for (i = 0; i < pages && !ret; i++) {
 			vm_fault_t vmf;
 			unsigned long off = i * PAGE_SIZE;
-			pfn_t pfn = phys_to_pfn_t(address + off, PFN_DEV);
+			pfn_t pfn = phys_to_pfn_t(address + off, 0);
 			vmf = vmf_insert_mixed(vma, vma->vm_start + off, pfn);
 			if (vmf & VM_FAULT_ERROR)
 				ret = vm_fault_to_errno(vmf, 0);
diff --git a/include/linux/pfn_t.h b/include/linux/pfn_t.h
index 75bb77c..034b5b0 100644
--- a/include/linux/pfn_t.h
+++ b/include/linux/pfn_t.h
@@ -11,10 +11,8 @@
  * PFN_MAP - pfn has a dynamic page mapping established by a device driver
  */
 #define PFN_FLAGS_MASK (((u64) (~PAGE_MASK)) << (BITS_PER_LONG_LONG - PAGE_SHIFT))
-#define PFN_DEV (1ULL << (BITS_PER_LONG_LONG - 3))
 
-#define PFN_FLAGS_TRACE \
-	{ PFN_DEV,	"DEV" }
+#define PFN_FLAGS_TRACE { }
 
 static inline pfn_t __pfn_to_pfn_t(unsigned long pfn, u64 flags)
 {
diff --git a/mm/memory.c b/mm/memory.c
index e1d647c..5f7a441 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2510,9 +2510,9 @@ vm_fault_t vmf_insert_pfn_prot(struct vm_area_struct *vma, unsigned long addr,
 	if (!pfn_modify_allowed(pfn, pgprot))
 		return VM_FAULT_SIGBUS;
 
-	track_pfn_insert(vma, &pgprot, __pfn_to_pfn_t(pfn, PFN_DEV));
+	track_pfn_insert(vma, &pgprot, __pfn_to_pfn_t(pfn, 0));
 
-	return insert_pfn(vma, addr, __pfn_to_pfn_t(pfn, PFN_DEV), pgprot,
+	return insert_pfn(vma, addr, __pfn_to_pfn_t(pfn, 0), pgprot,
 			false);
 }
 EXPORT_SYMBOL(vmf_insert_pfn_prot);
-- 
git-series 0.9.1

[RFC 3/4] mm: Remove callers of pfn_t functionality

[Alistair Popple]

All PFN_* pfn_t flags have been removed. Therefore there is no longer
a need for the pfn_t type and all uses can be replaced with normal
pfns.

Signed-off-by: Alistair Popple <apopple@nvidia.com>

---

I'm guessing people will want this split up into several patches for
merging/review. If so I will do that once the pre-requisite series
have landed in Linus tree and we've decided if this RFC is worthwhile.
---
 arch/x86/mm/pat/memtype.c                |  6 +--
 drivers/dax/device.c                     | 23 ++++++-------
 drivers/dax/hmem/hmem.c                  |  1 +-
 drivers/dax/kmem.c                       |  1 +-
 drivers/dax/pmem.c                       |  1 +-
 drivers/dax/super.c                      |  3 +--
 drivers/gpu/drm/exynos/exynos_drm_gem.c  |  1 +-
 drivers/gpu/drm/gma500/fbdev.c           |  3 +--
 drivers/gpu/drm/i915/gem/i915_gem_mman.c |  1 +-
 drivers/gpu/drm/msm/msm_gem.c            |  1 +-
 drivers/gpu/drm/omapdrm/omap_gem.c       |  6 +--
 drivers/gpu/drm/v3d/v3d_bo.c             |  1 +-
 drivers/md/dm-linear.c                   |  2 +-
 drivers/md/dm-log-writes.c               |  2 +-
 drivers/md/dm-stripe.c                   |  2 +-
 drivers/md/dm-target.c                   |  2 +-
 drivers/md/dm-writecache.c               |  9 ++---
 drivers/md/dm.c                          |  2 +-
 drivers/nvdimm/pmem.c                    |  8 +---
 drivers/nvdimm/pmem.h                    |  4 +--
 drivers/s390/block/dcssblk.c             |  9 ++---
 drivers/vfio/pci/vfio_pci_core.c         |  5 +--
 fs/cramfs/inode.c                        |  4 +--
 fs/dax.c                                 | 45 ++++++++++++-------------
 fs/ext4/file.c                           |  2 +-
 fs/fuse/dax.c                            |  3 +--
 fs/fuse/virtio_fs.c                      |  5 +--
 fs/xfs/xfs_file.c                        |  2 +-
 include/linux/dax.h                      |  8 ++--
 include/linux/device-mapper.h            |  2 +-
 include/linux/huge_mm.h                  |  4 +-
 include/linux/mm.h                       |  4 +-
 include/linux/pgtable.h                  |  4 +-
 include/trace/events/fs_dax.h            |  6 +--
 mm/debug_vm_pgtable.c                    |  1 +-
 mm/huge_memory.c                         | 23 ++++++-------
 mm/memory.c                              | 32 ++++++++----------
 mm/memremap.c                            |  1 +-
 mm/migrate.c                             |  1 +-
 tools/testing/nvdimm/pmem-dax.c          |  6 +--
 tools/testing/nvdimm/test/iomap.c        |  7 +----
 41 files changed, 108 insertions(+), 145 deletions(-)

diff --git a/arch/x86/mm/pat/memtype.c b/arch/x86/mm/pat/memtype.c
index feb8cc6..508f807 100644
--- a/arch/x86/mm/pat/memtype.c
+++ b/arch/x86/mm/pat/memtype.c
@@ -36,7 +36,6 @@
 #include <linux/debugfs.h>
 #include <linux/ioport.h>
 #include <linux/kernel.h>
-#include <linux/pfn_t.h>
 #include <linux/slab.h>
 #include <linux/mm.h>
 #include <linux/highmem.h>
@@ -1053,7 +1052,8 @@ int track_pfn_remap(struct vm_area_struct *vma, pgprot_t *prot,
 	return 0;
 }
 
-void track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot, pfn_t pfn)
+void track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot,
+		      unsigned long pfn)
 {
 	enum page_cache_mode pcm;
 
@@ -1061,7 +1061,7 @@ void track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot, pfn_t pfn)
 		return;
 
 	/* Set prot based on lookup */
-	pcm = lookup_memtype(pfn_t_to_phys(pfn));
+	pcm = lookup_memtype(PFN_PHYS(pfn));
 	*prot = __pgprot((pgprot_val(*prot) & (~_PAGE_CACHE_MASK)) |
 			 cachemode2protval(pcm));
 }
diff --git a/drivers/dax/device.c b/drivers/dax/device.c
index fd22dbf..37ffb2f 100644
--- a/drivers/dax/device.c
+++ b/drivers/dax/device.c
@@ -4,7 +4,6 @@
 #include <linux/pagemap.h>
 #include <linux/module.h>
 #include <linux/device.h>
-#include <linux/pfn_t.h>
 #include <linux/cdev.h>
 #include <linux/slab.h>
 #include <linux/dax.h>
@@ -73,7 +72,7 @@ __weak phys_addr_t dax_pgoff_to_phys(struct dev_dax *dev_dax, pgoff_t pgoff,
 	return -1;
 }
 
-static void dax_set_mapping(struct vm_fault *vmf, pfn_t pfn,
+static void dax_set_mapping(struct vm_fault *vmf, unsigned long pfn,
 			      unsigned long fault_size)
 {
 	unsigned long i, nr_pages = fault_size / PAGE_SIZE;
@@ -89,7 +88,7 @@ static void dax_set_mapping(struct vm_fault *vmf, pfn_t pfn,
 			ALIGN_DOWN(vmf->address, fault_size));
 
 	for (i = 0; i < nr_pages; i++) {
-		struct page *page = pfn_to_page(pfn_t_to_pfn(pfn) + i);
+		struct page *page = pfn_to_page(pfn + i);
 
 		page = compound_head(page);
 		if (page->mapping)
@@ -105,7 +104,7 @@ static vm_fault_t __dev_dax_pte_fault(struct dev_dax *dev_dax,
 {
 	struct device *dev = &dev_dax->dev;
 	phys_addr_t phys;
-	pfn_t pfn;
+	unsigned long pfn;
 	unsigned int fault_size = PAGE_SIZE;
 
 	if (check_vma(dev_dax, vmf->vma, __func__))
@@ -126,11 +125,11 @@ static vm_fault_t __dev_dax_pte_fault(struct dev_dax *dev_dax,
 		return VM_FAULT_SIGBUS;
 	}
 
-	pfn = phys_to_pfn_t(phys, 0);
+	pfn = PHYS_PFN(phys);
 
 	dax_set_mapping(vmf, pfn, fault_size);
 
-	return vmf_insert_page_mkwrite(vmf, pfn_t_to_page(pfn),
+	return vmf_insert_page_mkwrite(vmf, pfn_to_page(pfn),
 					vmf->flags & FAULT_FLAG_WRITE);
 }
 
@@ -141,7 +140,7 @@ static vm_fault_t __dev_dax_pmd_fault(struct dev_dax *dev_dax,
 	struct device *dev = &dev_dax->dev;
 	phys_addr_t phys;
 	pgoff_t pgoff;
-	pfn_t pfn;
+	unsigned long pfn;
 	unsigned int fault_size = PMD_SIZE;
 
 	if (check_vma(dev_dax, vmf->vma, __func__))
@@ -170,11 +169,11 @@ static vm_fault_t __dev_dax_pmd_fault(struct dev_dax *dev_dax,
 		return VM_FAULT_SIGBUS;
 	}
 
-	pfn = phys_to_pfn_t(phys, 0);
+	pfn = PHYS_PFN(phys);
 
 	dax_set_mapping(vmf, pfn, fault_size);
 
-	return vmf_insert_folio_pmd(vmf, page_folio(pfn_t_to_page(pfn)),
+	return vmf_insert_folio_pmd(vmf, page_folio(pfn_to_page(pfn)),
 				vmf->flags & FAULT_FLAG_WRITE);
 }
 
@@ -186,7 +185,7 @@ static vm_fault_t __dev_dax_pud_fault(struct dev_dax *dev_dax,
 	struct device *dev = &dev_dax->dev;
 	phys_addr_t phys;
 	pgoff_t pgoff;
-	pfn_t pfn;
+	unsigned long pfn;
 	unsigned int fault_size = PUD_SIZE;
 
 
@@ -216,11 +215,11 @@ static vm_fault_t __dev_dax_pud_fault(struct dev_dax *dev_dax,
 		return VM_FAULT_SIGBUS;
 	}
 
-	pfn = phys_to_pfn_t(phys, 0);
+	pfn = PHYS_PFN(phys);
 
 	dax_set_mapping(vmf, pfn, fault_size);
 
-	return vmf_insert_folio_pud(vmf, page_folio(pfn_t_to_page(pfn)),
+	return vmf_insert_folio_pud(vmf, page_folio(pfn_to_page(pfn)),
 				vmf->flags & FAULT_FLAG_WRITE);
 }
 #else
diff --git a/drivers/dax/hmem/hmem.c b/drivers/dax/hmem/hmem.c
index 5e7c53f..c18451a 100644
--- a/drivers/dax/hmem/hmem.c
+++ b/drivers/dax/hmem/hmem.c
@@ -2,7 +2,6 @@
 #include <linux/platform_device.h>
 #include <linux/memregion.h>
 #include <linux/module.h>
-#include <linux/pfn_t.h>
 #include <linux/dax.h>
 #include "../bus.h"
 
diff --git a/drivers/dax/kmem.c b/drivers/dax/kmem.c
index e97d47f..87b5321 100644
--- a/drivers/dax/kmem.c
+++ b/drivers/dax/kmem.c
@@ -5,7 +5,6 @@
 #include <linux/memory.h>
 #include <linux/module.h>
 #include <linux/device.h>
-#include <linux/pfn_t.h>
 #include <linux/slab.h>
 #include <linux/dax.h>
 #include <linux/fs.h>
diff --git a/drivers/dax/pmem.c b/drivers/dax/pmem.c
index c8ebf4e..bee9306 100644
--- a/drivers/dax/pmem.c
+++ b/drivers/dax/pmem.c
@@ -2,7 +2,6 @@
 /* Copyright(c) 2016 - 2018 Intel Corporation. All rights reserved. */
 #include <linux/memremap.h>
 #include <linux/module.h>
-#include <linux/pfn_t.h>
 #include "../nvdimm/pfn.h"
 #include "../nvdimm/nd.h"
 #include "bus.h"
diff --git a/drivers/dax/super.c b/drivers/dax/super.c
index e16d1d4..54c480e 100644
--- a/drivers/dax/super.c
+++ b/drivers/dax/super.c
@@ -7,7 +7,6 @@
 #include <linux/mount.h>
 #include <linux/pseudo_fs.h>
 #include <linux/magic.h>
-#include <linux/pfn_t.h>
 #include <linux/cdev.h>
 #include <linux/slab.h>
 #include <linux/uio.h>
@@ -148,7 +147,7 @@ enum dax_device_flags {
  * pages accessible at the device relative @pgoff.
  */
 long dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, long nr_pages,
-		enum dax_access_mode mode, void **kaddr, pfn_t *pfn)
+		enum dax_access_mode mode, void **kaddr, unsigned long *pfn)
 {
 	long avail;
 
diff --git a/drivers/gpu/drm/exynos/exynos_drm_gem.c b/drivers/gpu/drm/exynos/exynos_drm_gem.c
index 4787fee..84b2172 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_gem.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_gem.c
@@ -7,7 +7,6 @@
 
 
 #include <linux/dma-buf.h>
-#include <linux/pfn_t.h>
 #include <linux/shmem_fs.h>
 #include <linux/module.h>
 
diff --git a/drivers/gpu/drm/gma500/fbdev.c b/drivers/gpu/drm/gma500/fbdev.c
index 109efdc..68b825f 100644
--- a/drivers/gpu/drm/gma500/fbdev.c
+++ b/drivers/gpu/drm/gma500/fbdev.c
@@ -6,7 +6,6 @@
  **************************************************************************/
 
 #include <linux/fb.h>
-#include <linux/pfn_t.h>
 
 #include <drm/drm_crtc_helper.h>
 #include <drm/drm_drv.h>
@@ -33,7 +32,7 @@ static vm_fault_t psb_fbdev_vm_fault(struct vm_fault *vmf)
 	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 
 	for (i = 0; i < page_num; ++i) {
-		err = vmf_insert_mixed(vma, address, __pfn_to_pfn_t(pfn, 0));
+		err = vmf_insert_mixed(vma, address, pfn);
 		if (unlikely(err & VM_FAULT_ERROR))
 			break;
 		address += PAGE_SIZE;
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
index 21274aa..d6ac557 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
@@ -6,7 +6,6 @@
 
 #include <linux/anon_inodes.h>
 #include <linux/mman.h>
-#include <linux/pfn_t.h>
 #include <linux/sizes.h>
 
 #include <drm/drm_cache.h>
diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c
index ebc9ba6..1c27500 100644
--- a/drivers/gpu/drm/msm/msm_gem.c
+++ b/drivers/gpu/drm/msm/msm_gem.c
@@ -9,7 +9,6 @@
 #include <linux/spinlock.h>
 #include <linux/shmem_fs.h>
 #include <linux/dma-buf.h>
-#include <linux/pfn_t.h>
 
 #include <drm/drm_prime.h>
 #include <drm/drm_file.h>
diff --git a/drivers/gpu/drm/omapdrm/omap_gem.c b/drivers/gpu/drm/omapdrm/omap_gem.c
index 9df05b2..381552b 100644
--- a/drivers/gpu/drm/omapdrm/omap_gem.c
+++ b/drivers/gpu/drm/omapdrm/omap_gem.c
@@ -8,7 +8,6 @@
 #include <linux/seq_file.h>
 #include <linux/shmem_fs.h>
 #include <linux/spinlock.h>
-#include <linux/pfn_t.h>
 #include <linux/vmalloc.h>
 
 #include <drm/drm_prime.h>
@@ -371,7 +370,7 @@ static vm_fault_t omap_gem_fault_1d(struct drm_gem_object *obj,
 	VERB("Inserting %p pfn %lx, pa %lx", (void *)vmf->address,
 			pfn, pfn << PAGE_SHIFT);
 
-	return vmf_insert_mixed(vma, vmf->address, __pfn_to_pfn_t(pfn, 0));
+	return vmf_insert_mixed(vma, vmf->address, pfn);
 }
 
 /* Special handling for the case of faulting in 2d tiled buffers */
@@ -466,8 +465,7 @@ static vm_fault_t omap_gem_fault_2d(struct drm_gem_object *obj,
 			pfn, pfn << PAGE_SHIFT);
 
 	for (i = n; i > 0; i--) {
-		ret = vmf_insert_mixed(vma,
-			vaddr, __pfn_to_pfn_t(pfn, 0));
+		ret = vmf_insert_mixed(vma, vaddr, pfn);
 		if (ret & VM_FAULT_ERROR)
 			break;
 		pfn += priv->usergart[fmt].stride_pfn;
diff --git a/drivers/gpu/drm/v3d/v3d_bo.c b/drivers/gpu/drm/v3d/v3d_bo.c
index bb78155..c41476d 100644
--- a/drivers/gpu/drm/v3d/v3d_bo.c
+++ b/drivers/gpu/drm/v3d/v3d_bo.c
@@ -16,7 +16,6 @@
  */
 
 #include <linux/dma-buf.h>
-#include <linux/pfn_t.h>
 #include <linux/vmalloc.h>
 
 #include "v3d_drv.h"
diff --git a/drivers/md/dm-linear.c b/drivers/md/dm-linear.c
index 49fb0f6..ba676e3 100644
--- a/drivers/md/dm-linear.c
+++ b/drivers/md/dm-linear.c
@@ -168,7 +168,7 @@ static struct dax_device *linear_dax_pgoff(struct dm_target *ti, pgoff_t *pgoff)
 
 static long linear_dax_direct_access(struct dm_target *ti, pgoff_t pgoff,
 		long nr_pages, enum dax_access_mode mode, void **kaddr,
-		pfn_t *pfn)
+		unsigned long *pfn)
 {
 	struct dax_device *dax_dev = linear_dax_pgoff(ti, &pgoff);
 
diff --git a/drivers/md/dm-log-writes.c b/drivers/md/dm-log-writes.c
index 8d7df83..4c6aed7 100644
--- a/drivers/md/dm-log-writes.c
+++ b/drivers/md/dm-log-writes.c
@@ -891,7 +891,7 @@ static struct dax_device *log_writes_dax_pgoff(struct dm_target *ti,
 
 static long log_writes_dax_direct_access(struct dm_target *ti, pgoff_t pgoff,
 		long nr_pages, enum dax_access_mode mode, void **kaddr,
-		pfn_t *pfn)
+		unsigned long *pfn)
 {
 	struct dax_device *dax_dev = log_writes_dax_pgoff(ti, &pgoff);
 
diff --git a/drivers/md/dm-stripe.c b/drivers/md/dm-stripe.c
index 4112071..5804bf2 100644
--- a/drivers/md/dm-stripe.c
+++ b/drivers/md/dm-stripe.c
@@ -316,7 +316,7 @@ static struct dax_device *stripe_dax_pgoff(struct dm_target *ti, pgoff_t *pgoff)
 
 static long stripe_dax_direct_access(struct dm_target *ti, pgoff_t pgoff,
 		long nr_pages, enum dax_access_mode mode, void **kaddr,
-		pfn_t *pfn)
+		unsigned long *pfn)
 {
 	struct dax_device *dax_dev = stripe_dax_pgoff(ti, &pgoff);
 
diff --git a/drivers/md/dm-target.c b/drivers/md/dm-target.c
index 652627a..2af5a95 100644
--- a/drivers/md/dm-target.c
+++ b/drivers/md/dm-target.c
@@ -255,7 +255,7 @@ static void io_err_io_hints(struct dm_target *ti, struct queue_limits *limits)
 
 static long io_err_dax_direct_access(struct dm_target *ti, pgoff_t pgoff,
 		long nr_pages, enum dax_access_mode mode, void **kaddr,
-		pfn_t *pfn)
+		unsigned long *pfn)
 {
 	return -EIO;
 }
diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c
index 7ce8847..27d240d 100644
--- a/drivers/md/dm-writecache.c
+++ b/drivers/md/dm-writecache.c
@@ -13,7 +13,6 @@
 #include <linux/dm-io.h>
 #include <linux/dm-kcopyd.h>
 #include <linux/dax.h>
-#include <linux/pfn_t.h>
 #include <linux/libnvdimm.h>
 #include <linux/delay.h>
 #include "dm-io-tracker.h"
@@ -256,7 +255,7 @@ static int persistent_memory_claim(struct dm_writecache *wc)
 	int r;
 	loff_t s;
 	long p, da;
-	pfn_t pfn;
+	unsigned long pfn;
 	int id;
 	struct page **pages;
 	sector_t offset;
@@ -290,7 +289,7 @@ static int persistent_memory_claim(struct dm_writecache *wc)
 		r = da;
 		goto err2;
 	}
-	if (!pfn_t_has_page(pfn)) {
+	if (!pfn_valid(pfn)) {
 		wc->memory_map = NULL;
 		r = -EOPNOTSUPP;
 		goto err2;
@@ -314,12 +313,12 @@ static int persistent_memory_claim(struct dm_writecache *wc)
 				r = daa ? daa : -EINVAL;
 				goto err3;
 			}
-			if (!pfn_t_has_page(pfn)) {
+			if (!pfn_valid(pfn)) {
 				r = -EOPNOTSUPP;
 				goto err3;
 			}
 			while (daa-- && i < p) {
-				pages[i++] = pfn_t_to_page(pfn);
+				pages[i++] = pfn_to_page(pfn);
 				pfn.val++;
 				if (!(i & 15))
 					cond_resched();
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 12ecf07..eb68926 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1232,7 +1232,7 @@ static struct dm_target *dm_dax_get_live_target(struct mapped_device *md,
 
 static long dm_dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff,
 		long nr_pages, enum dax_access_mode mode, void **kaddr,
-		pfn_t *pfn)
+		unsigned long *pfn)
 {
 	struct mapped_device *md = dax_get_private(dax_dev);
 	sector_t sector = pgoff * PAGE_SECTORS;
diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index 785b2d2..ae4f5a4 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -20,7 +20,6 @@
 #include <linux/kstrtox.h>
 #include <linux/vmalloc.h>
 #include <linux/blk-mq.h>
-#include <linux/pfn_t.h>
 #include <linux/slab.h>
 #include <linux/uio.h>
 #include <linux/dax.h>
@@ -242,7 +241,7 @@ static void pmem_submit_bio(struct bio *bio)
 /* see "strong" declaration in tools/testing/nvdimm/pmem-dax.c */
 __weak long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff,
 		long nr_pages, enum dax_access_mode mode, void **kaddr,
-		pfn_t *pfn)
+		unsigned long *pfn)
 {
 	resource_size_t offset = PFN_PHYS(pgoff) + pmem->data_offset;
 	sector_t sector = PFN_PHYS(pgoff) >> SECTOR_SHIFT;
@@ -254,7 +253,7 @@ __weak long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff,
 	if (kaddr)
 		*kaddr = pmem->virt_addr + offset;
 	if (pfn)
-		*pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags);
+		*pfn = PHYS_PFN(pmem->phys_addr + offset);
 
 	if (bb->count &&
 	    badblocks_check(bb, sector, num, &first_bad, &num_bad)) {
@@ -303,7 +302,7 @@ static int pmem_dax_zero_page_range(struct dax_device *dax_dev, pgoff_t pgoff,
 
 static long pmem_dax_direct_access(struct dax_device *dax_dev,
 		pgoff_t pgoff, long nr_pages, enum dax_access_mode mode,
-		void **kaddr, pfn_t *pfn)
+		void **kaddr, unsigned long *pfn)
 {
 	struct pmem_device *pmem = dax_get_private(dax_dev);
 
@@ -513,7 +512,6 @@ static int pmem_attach_disk(struct device *dev,
 
 	pmem->disk = disk;
 	pmem->pgmap.owner = pmem;
-	pmem->pfn_flags = 0;
 	if (is_nd_pfn(dev)) {
 		pmem->pgmap.type = MEMORY_DEVICE_FS_DAX;
 		pmem->pgmap.ops = &fsdax_pagemap_ops;
diff --git a/drivers/nvdimm/pmem.h b/drivers/nvdimm/pmem.h
index 392b0b3..a48509f 100644
--- a/drivers/nvdimm/pmem.h
+++ b/drivers/nvdimm/pmem.h
@@ -5,7 +5,6 @@
 #include <linux/badblocks.h>
 #include <linux/memremap.h>
 #include <linux/types.h>
-#include <linux/pfn_t.h>
 #include <linux/fs.h>
 
 enum dax_access_mode;
@@ -16,7 +15,6 @@ struct pmem_device {
 	phys_addr_t		phys_addr;
 	/* when non-zero this device is hosting a 'pfn' instance */
 	phys_addr_t		data_offset;
-	u64			pfn_flags;
 	void			*virt_addr;
 	/* immutable base size of the namespace */
 	size_t			size;
@@ -31,7 +29,7 @@ struct pmem_device {
 
 long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff,
 		long nr_pages, enum dax_access_mode mode, void **kaddr,
-		pfn_t *pfn);
+		unsigned long *pfn);
 
 #ifdef CONFIG_MEMORY_FAILURE
 static inline bool test_and_clear_pmem_poison(struct page *page)
diff --git a/drivers/s390/block/dcssblk.c b/drivers/s390/block/dcssblk.c
index 8a0d590..3e01c10 100644
--- a/drivers/s390/block/dcssblk.c
+++ b/drivers/s390/block/dcssblk.c
@@ -17,7 +17,6 @@
 #include <linux/blkdev.h>
 #include <linux/completion.h>
 #include <linux/interrupt.h>
-#include <linux/pfn_t.h>
 #include <linux/uio.h>
 #include <linux/dax.h>
 #include <linux/io.h>
@@ -33,7 +32,7 @@ static void dcssblk_release(struct gendisk *disk);
 static void dcssblk_submit_bio(struct bio *bio);
 static long dcssblk_dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff,
 		long nr_pages, enum dax_access_mode mode, void **kaddr,
-		pfn_t *pfn);
+		unsigned long *pfn);
 
 static char dcssblk_segments[DCSSBLK_PARM_LEN] = "\0";
 
@@ -915,7 +914,7 @@ dcssblk_submit_bio(struct bio *bio)
 
 static long
 __dcssblk_direct_access(struct dcssblk_dev_info *dev_info, pgoff_t pgoff,
-		long nr_pages, void **kaddr, pfn_t *pfn)
+		long nr_pages, void **kaddr, unsigned long *pfn)
 {
 	resource_size_t offset = pgoff * PAGE_SIZE;
 	unsigned long dev_sz;
@@ -924,7 +923,7 @@ __dcssblk_direct_access(struct dcssblk_dev_info *dev_info, pgoff_t pgoff,
 	if (kaddr)
 		*kaddr = __va(dev_info->start + offset);
 	if (pfn)
-		*pfn = __pfn_to_pfn_t(PFN_DOWN(dev_info->start + offset), 0);
+		*pfn = PFN_DOWN(dev_info->start + offset);
 
 	return (dev_sz - offset) / PAGE_SIZE;
 }
@@ -932,7 +931,7 @@ __dcssblk_direct_access(struct dcssblk_dev_info *dev_info, pgoff_t pgoff,
 static long
 dcssblk_dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff,
 		long nr_pages, enum dax_access_mode mode, void **kaddr,
-		pfn_t *pfn)
+		unsigned long *pfn)
 {
 	struct dcssblk_dev_info *dev_info = dax_get_private(dax_dev);
 
diff --git a/drivers/vfio/pci/vfio_pci_core.c b/drivers/vfio/pci/vfio_pci_core.c
index e6b6c01..2dfc3fe 100644
--- a/drivers/vfio/pci/vfio_pci_core.c
+++ b/drivers/vfio/pci/vfio_pci_core.c
@@ -20,7 +20,6 @@
 #include <linux/mutex.h>
 #include <linux/notifier.h>
 #include <linux/pci.h>
-#include <linux/pfn_t.h>
 #include <linux/pm_runtime.h>
 #include <linux/slab.h>
 #include <linux/types.h>
@@ -1680,12 +1679,12 @@ static vm_fault_t vfio_pci_mmap_huge_fault(struct vm_fault *vmf,
 		break;
 #ifdef CONFIG_ARCH_SUPPORTS_PMD_PFNMAP
 	case PMD_ORDER:
-		ret = vmf_insert_pfn_pmd(vmf, __pfn_to_pfn_t(pfn + pgoff, 0), false);
+		ret = vmf_insert_pfn_pmd(vmf, pfn + pgoff, false);
 		break;
 #endif
 #ifdef CONFIG_ARCH_SUPPORTS_PUD_PFNMAP
 	case PUD_ORDER:
-		ret = vmf_insert_pfn_pud(vmf, __pfn_to_pfn_t(pfn + pgoff, 0), false);
+		ret = vmf_insert_pfn_pud(vmf, pfn + pgoff, false);
 		break;
 #endif
 	default:
diff --git a/fs/cramfs/inode.c b/fs/cramfs/inode.c
index 820a664..3358bc6 100644
--- a/fs/cramfs/inode.c
+++ b/fs/cramfs/inode.c
@@ -17,7 +17,6 @@
 #include <linux/fs.h>
 #include <linux/file.h>
 #include <linux/pagemap.h>
-#include <linux/pfn_t.h>
 #include <linux/ramfs.h>
 #include <linux/init.h>
 #include <linux/string.h>
@@ -412,8 +411,7 @@ static int cramfs_physmem_mmap(struct file *file, struct vm_area_struct *vma)
 		for (i = 0; i < pages && !ret; i++) {
 			vm_fault_t vmf;
 			unsigned long off = i * PAGE_SIZE;
-			pfn_t pfn = phys_to_pfn_t(address + off, 0);
-			vmf = vmf_insert_mixed(vma, vma->vm_start + off, pfn);
+			vmf = vmf_insert_mixed(vma, vma->vm_start + off, address + off);
 			if (vmf & VM_FAULT_ERROR)
 				ret = vm_fault_to_errno(vmf, 0);
 		}
diff --git a/fs/dax.c b/fs/dax.c
index 3cc5b73..d13aa95 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -20,7 +20,6 @@
 #include <linux/sched/signal.h>
 #include <linux/uio.h>
 #include <linux/vmstat.h>
-#include <linux/pfn_t.h>
 #include <linux/sizes.h>
 #include <linux/mmu_notifier.h>
 #include <linux/iomap.h>
@@ -76,9 +75,9 @@ static struct folio *dax_to_folio(void *entry)
 	return page_folio(pfn_to_page(dax_to_pfn(entry)));
 }
 
-static void *dax_make_entry(pfn_t pfn, unsigned long flags)
+static void *dax_make_entry(unsigned long pfn, unsigned long flags)
 {
-	return xa_mk_value(flags | (pfn_t_to_pfn(pfn) << DAX_SHIFT));
+	return xa_mk_value(flags | (pfn << DAX_SHIFT));
 }
 
 static bool dax_is_locked(void *entry)
@@ -708,7 +707,7 @@ static void *grab_mapping_entry(struct xa_state *xas,
 
 		if (order > 0)
 			flags |= DAX_PMD;
-		entry = dax_make_entry(pfn_to_pfn_t(0), flags);
+		entry = dax_make_entry(0, flags);
 		dax_lock_entry(xas, entry);
 		if (xas_error(xas))
 			goto out_unlock;
@@ -1031,7 +1030,7 @@ static bool dax_fault_is_synchronous(const struct iomap_iter *iter,
  * appropriate.
  */
 static void *dax_insert_entry(struct xa_state *xas, struct vm_fault *vmf,
-		const struct iomap_iter *iter, void *entry, pfn_t pfn,
+		const struct iomap_iter *iter, void *entry, unsigned long pfn,
 		unsigned long flags)
 {
 	struct address_space *mapping = vmf->vma->vm_file->f_mapping;
@@ -1230,7 +1229,7 @@ int dax_writeback_mapping_range(struct address_space *mapping,
 EXPORT_SYMBOL_GPL(dax_writeback_mapping_range);
 
 static int dax_iomap_direct_access(const struct iomap *iomap, loff_t pos,
-		size_t size, void **kaddr, pfn_t *pfnp)
+		size_t size, void **kaddr, unsigned long *pfnp)
 {
 	pgoff_t pgoff = dax_iomap_pgoff(iomap, pos);
 	int id, rc = 0;
@@ -1248,7 +1247,7 @@ static int dax_iomap_direct_access(const struct iomap *iomap, loff_t pos,
 	rc = -EINVAL;
 	if (PFN_PHYS(length) < size)
 		goto out;
-	if (pfn_t_to_pfn(*pfnp) & (PHYS_PFN(size)-1))
+	if (*pfnp & (PHYS_PFN(size)-1))
 		goto out;
 
 	rc = 0;
@@ -1352,12 +1351,12 @@ static vm_fault_t dax_load_hole(struct xa_state *xas, struct vm_fault *vmf,
 {
 	struct inode *inode = iter->inode;
 	unsigned long vaddr = vmf->address;
-	pfn_t pfn = pfn_to_pfn_t(my_zero_pfn(vaddr));
+	unsigned long pfn = my_zero_pfn(vaddr);
 	vm_fault_t ret;
 
 	*entry = dax_insert_entry(xas, vmf, iter, *entry, pfn, DAX_ZERO_PAGE);
 
-	ret = vmf_insert_page_mkwrite(vmf, pfn_t_to_page(pfn), false);
+	ret = vmf_insert_page_mkwrite(vmf, pfn_to_page(pfn), false);
 	trace_dax_load_hole(inode, vmf, ret);
 	return ret;
 }
@@ -1374,14 +1373,14 @@ static vm_fault_t dax_pmd_load_hole(struct xa_state *xas, struct vm_fault *vmf,
 	struct folio *zero_folio;
 	spinlock_t *ptl;
 	pmd_t pmd_entry;
-	pfn_t pfn;
+	unsigned long pfn;
 
 	zero_folio = mm_get_huge_zero_folio(vmf->vma->vm_mm);
 
 	if (unlikely(!zero_folio))
 		goto fallback;
 
-	pfn = page_to_pfn_t(&zero_folio->page);
+	pfn = page_to_pfn(&zero_folio->page);
 	*entry = dax_insert_entry(xas, vmf, iter, *entry, pfn,
 				  DAX_PMD | DAX_ZERO_PAGE);
 
@@ -1771,7 +1770,7 @@ static vm_fault_t dax_fault_return(int error)
  * insertion for now and return the pfn so that caller can insert it after the
  * fsync is done.
  */
-static vm_fault_t dax_fault_synchronous_pfnp(pfn_t *pfnp, pfn_t pfn)
+static vm_fault_t dax_fault_synchronous_pfnp(unsigned long *pfnp, unsigned long pfn)
 {
 	if (WARN_ON_ONCE(!pfnp))
 		return VM_FAULT_SIGBUS;
@@ -1819,7 +1818,7 @@ static vm_fault_t dax_fault_cow_page(struct vm_fault *vmf,
  * @pmd:	distinguish whether it is a pmd fault
  */
 static vm_fault_t dax_fault_iter(struct vm_fault *vmf,
-		const struct iomap_iter *iter, pfn_t *pfnp,
+		const struct iomap_iter *iter, unsigned long *pfnp,
 		struct xa_state *xas, void **entry, bool pmd)
 {
 	const struct iomap *iomap = &iter->iomap;
@@ -1830,7 +1829,7 @@ static vm_fault_t dax_fault_iter(struct vm_fault *vmf,
 	unsigned long entry_flags = pmd ? DAX_PMD : 0;
 	struct folio *folio;
 	int ret, err = 0;
-	pfn_t pfn;
+	unsigned long pfn;
 	void *kaddr;
 
 	if (!pmd && vmf->cow_page)
@@ -1867,15 +1866,15 @@ static vm_fault_t dax_fault_iter(struct vm_fault *vmf,
 
 	folio_ref_inc(folio);
 	if (pmd)
-		ret = vmf_insert_folio_pmd(vmf, pfn_folio(pfn_t_to_pfn(pfn)), write);
+		ret = vmf_insert_folio_pmd(vmf, pfn_folio(pfn), write);
 	else
-		ret = vmf_insert_page_mkwrite(vmf, pfn_t_to_page(pfn), write);
+		ret = vmf_insert_page_mkwrite(vmf, pfn_to_page(pfn), write);
 	folio_put(folio);
 
 	return ret;
 }
 
-static vm_fault_t dax_iomap_pte_fault(struct vm_fault *vmf, pfn_t *pfnp,
+static vm_fault_t dax_iomap_pte_fault(struct vm_fault *vmf, unsigned long *pfnp,
 			       int *iomap_errp, const struct iomap_ops *ops)
 {
 	struct address_space *mapping = vmf->vma->vm_file->f_mapping;
@@ -1985,7 +1984,7 @@ static bool dax_fault_check_fallback(struct vm_fault *vmf, struct xa_state *xas,
 	return false;
 }
 
-static vm_fault_t dax_iomap_pmd_fault(struct vm_fault *vmf, pfn_t *pfnp,
+static vm_fault_t dax_iomap_pmd_fault(struct vm_fault *vmf, unsigned long *pfnp,
 			       const struct iomap_ops *ops)
 {
 	struct address_space *mapping = vmf->vma->vm_file->f_mapping;
@@ -2064,7 +2063,7 @@ static vm_fault_t dax_iomap_pmd_fault(struct vm_fault *vmf, pfn_t *pfnp,
 	return ret;
 }
 #else
-static vm_fault_t dax_iomap_pmd_fault(struct vm_fault *vmf, pfn_t *pfnp,
+static vm_fault_t dax_iomap_pmd_fault(struct vm_fault *vmf, unsigned long *pfnp,
 			       const struct iomap_ops *ops)
 {
 	return VM_FAULT_FALLBACK;
@@ -2085,7 +2084,7 @@ static vm_fault_t dax_iomap_pmd_fault(struct vm_fault *vmf, pfn_t *pfnp,
  * successfully.
  */
 vm_fault_t dax_iomap_fault(struct vm_fault *vmf, unsigned int order,
-		    pfn_t *pfnp, int *iomap_errp, const struct iomap_ops *ops)
+		    unsigned long *pfnp, int *iomap_errp, const struct iomap_ops *ops)
 {
 	if (order == 0)
 		return dax_iomap_pte_fault(vmf, pfnp, iomap_errp, ops);
@@ -2106,7 +2105,7 @@ EXPORT_SYMBOL_GPL(dax_iomap_fault);
  * for an mmaped DAX file.  It also marks the page cache entry as dirty.
  */
 static vm_fault_t
-dax_insert_pfn_mkwrite(struct vm_fault *vmf, pfn_t pfn, unsigned int order)
+dax_insert_pfn_mkwrite(struct vm_fault *vmf, unsigned long pfn, unsigned int order)
 {
 	struct address_space *mapping = vmf->vma->vm_file->f_mapping;
 	XA_STATE_ORDER(xas, &mapping->i_pages, vmf->pgoff, order);
@@ -2128,7 +2127,7 @@ dax_insert_pfn_mkwrite(struct vm_fault *vmf, pfn_t pfn, unsigned int order)
 	xas_set_mark(&xas, PAGECACHE_TAG_DIRTY);
 	dax_lock_entry(&xas, entry);
 	xas_unlock_irq(&xas);
-	folio = pfn_folio(pfn_t_to_pfn(pfn));
+	folio = pfn_folio(pfn);
 	folio_ref_inc(folio);
 	if (order == 0)
 		ret = vmf_insert_page_mkwrite(vmf, &folio->page, true);
@@ -2155,7 +2154,7 @@ dax_insert_pfn_mkwrite(struct vm_fault *vmf, pfn_t pfn, unsigned int order)
  * table entry.
  */
 vm_fault_t dax_finish_sync_fault(struct vm_fault *vmf, unsigned int order,
-		pfn_t pfn)
+		unsigned long pfn)
 {
 	int err;
 	loff_t start = ((loff_t)vmf->pgoff) << PAGE_SHIFT;
diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index a520514..608dcbb 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -741,7 +741,7 @@ static vm_fault_t ext4_dax_huge_fault(struct vm_fault *vmf, unsigned int order)
 	bool write = (vmf->flags & FAULT_FLAG_WRITE) &&
 		(vmf->vma->vm_flags & VM_SHARED);
 	struct address_space *mapping = vmf->vma->vm_file->f_mapping;
-	pfn_t pfn;
+	unsigned long pfn;
 
 	if (write) {
 		sb_start_pagefault(sb);
diff --git a/fs/fuse/dax.c b/fs/fuse/dax.c
index 48d0652..8fb4843 100644
--- a/fs/fuse/dax.c
+++ b/fs/fuse/dax.c
@@ -10,7 +10,6 @@
 #include <linux/dax.h>
 #include <linux/uio.h>
 #include <linux/pagemap.h>
-#include <linux/pfn_t.h>
 #include <linux/iomap.h>
 #include <linux/interval_tree.h>
 
@@ -763,7 +762,7 @@ static vm_fault_t __fuse_dax_fault(struct vm_fault *vmf, unsigned int order,
 	vm_fault_t ret;
 	struct inode *inode = file_inode(vmf->vma->vm_file);
 	struct super_block *sb = inode->i_sb;
-	pfn_t pfn;
+	unsigned long pfn;
 	int error = 0;
 	struct fuse_conn *fc = get_fuse_conn(inode);
 	struct fuse_conn_dax *fcd = fc->dax;
diff --git a/fs/fuse/virtio_fs.c b/fs/fuse/virtio_fs.c
index 2c7b24c..d0b6612 100644
--- a/fs/fuse/virtio_fs.c
+++ b/fs/fuse/virtio_fs.c
@@ -9,7 +9,6 @@
 #include <linux/pci.h>
 #include <linux/interrupt.h>
 #include <linux/group_cpus.h>
-#include <linux/pfn_t.h>
 #include <linux/memremap.h>
 #include <linux/module.h>
 #include <linux/virtio.h>
@@ -1008,7 +1007,7 @@ static void virtio_fs_cleanup_vqs(struct virtio_device *vdev)
  */
 static long virtio_fs_direct_access(struct dax_device *dax_dev, pgoff_t pgoff,
 				    long nr_pages, enum dax_access_mode mode,
-				    void **kaddr, pfn_t *pfn)
+				    void **kaddr, unsigned long *pfn)
 {
 	struct virtio_fs *fs = dax_get_private(dax_dev);
 	phys_addr_t offset = PFN_PHYS(pgoff);
@@ -1017,7 +1016,7 @@ static long virtio_fs_direct_access(struct dax_device *dax_dev, pgoff_t pgoff,
 	if (kaddr)
 		*kaddr = fs->window_kaddr + offset;
 	if (pfn)
-		*pfn = phys_to_pfn_t(fs->window_phys_addr + offset, 0);
+		*pfn = fs->window_phys_addr + offset;
 	return nr_pages > max_nr_pages ? max_nr_pages : nr_pages;
 }
 
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index f7a7d89..e80b817 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -1426,7 +1426,7 @@ xfs_dax_fault_locked(
 	bool			write_fault)
 {
 	vm_fault_t		ret;
-	pfn_t			pfn;
+	unsigned long		pfn;
 
 	if (!IS_ENABLED(CONFIG_FS_DAX)) {
 		ASSERT(0);
diff --git a/include/linux/dax.h b/include/linux/dax.h
index dbefea1..95e53ed 100644
--- a/include/linux/dax.h
+++ b/include/linux/dax.h
@@ -26,7 +26,7 @@ struct dax_operations {
 	 * number of pages available for DAX at that pfn.
 	 */
 	long (*direct_access)(struct dax_device *, pgoff_t, long,
-			enum dax_access_mode, void **, pfn_t *);
+			enum dax_access_mode, void **, unsigned long *);
 	/* zero_page_range: required operation. Zero page range   */
 	int (*zero_page_range)(struct dax_device *, pgoff_t, size_t);
 	/*
@@ -249,7 +249,7 @@ static inline void dax_break_mapping_uninterruptible(struct inode *inode,
 bool dax_alive(struct dax_device *dax_dev);
 void *dax_get_private(struct dax_device *dax_dev);
 long dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, long nr_pages,
-		enum dax_access_mode mode, void **kaddr, pfn_t *pfn);
+		enum dax_access_mode mode, void **kaddr, unsigned long *pfn);
 size_t dax_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr,
 		size_t bytes, struct iov_iter *i);
 size_t dax_copy_to_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr,
@@ -263,9 +263,9 @@ void dax_flush(struct dax_device *dax_dev, void *addr, size_t size);
 ssize_t dax_iomap_rw(struct kiocb *iocb, struct iov_iter *iter,
 		const struct iomap_ops *ops);
 vm_fault_t dax_iomap_fault(struct vm_fault *vmf, unsigned int order,
-		    pfn_t *pfnp, int *errp, const struct iomap_ops *ops);
+		    unsigned long *pfnp, int *errp, const struct iomap_ops *ops);
 vm_fault_t dax_finish_sync_fault(struct vm_fault *vmf,
-		unsigned int order, pfn_t pfn);
+		unsigned int order, unsigned long pfn);
 int dax_delete_mapping_entry(struct address_space *mapping, pgoff_t index);
 void dax_delete_mapping_range(struct address_space *mapping,
 				loff_t start, loff_t end);
diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index 8321f65..d2ed4e9 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -149,7 +149,7 @@ typedef int (*dm_busy_fn) (struct dm_target *ti);
  */
 typedef long (*dm_dax_direct_access_fn) (struct dm_target *ti, pgoff_t pgoff,
 		long nr_pages, enum dax_access_mode node, void **kaddr,
-		pfn_t *pfn);
+		unsigned long *pfn);
 typedef int (*dm_dax_zero_page_range_fn)(struct dm_target *ti, pgoff_t pgoff,
 		size_t nr_pages);
 
diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
index 9cb5227..65a5f00 100644
--- a/include/linux/huge_mm.h
+++ b/include/linux/huge_mm.h
@@ -37,8 +37,8 @@ int change_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
 		    pmd_t *pmd, unsigned long addr, pgprot_t newprot,
 		    unsigned long cp_flags);
 
-vm_fault_t vmf_insert_pfn_pmd(struct vm_fault *vmf, pfn_t pfn, bool write);
-vm_fault_t vmf_insert_pfn_pud(struct vm_fault *vmf, pfn_t pfn, bool write);
+vm_fault_t vmf_insert_pfn_pmd(struct vm_fault *vmf, unsigned long pfn, bool write);
+vm_fault_t vmf_insert_pfn_pud(struct vm_fault *vmf, unsigned long pfn, bool write);
 vm_fault_t vmf_insert_folio_pmd(struct vm_fault *vmf, struct folio *folio, bool write);
 vm_fault_t vmf_insert_folio_pud(struct vm_fault *vmf, struct folio *folio, bool write);
 
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 23c4e9b..08c40da 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -3601,9 +3601,9 @@ vm_fault_t vmf_insert_pfn(struct vm_area_struct *vma, unsigned long addr,
 vm_fault_t vmf_insert_pfn_prot(struct vm_area_struct *vma, unsigned long addr,
 			unsigned long pfn, pgprot_t pgprot);
 vm_fault_t vmf_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
-			pfn_t pfn);
+			unsigned long pfn);
 vm_fault_t vmf_insert_mixed_mkwrite(struct vm_area_struct *vma,
-		unsigned long addr, pfn_t pfn);
+		unsigned long addr, unsigned long pfn);
 int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long len);
 
 static inline vm_fault_t vmf_insert_page(struct vm_area_struct *vma,
diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h
index 1c377de..e57bfb6 100644
--- a/include/linux/pgtable.h
+++ b/include/linux/pgtable.h
@@ -1503,7 +1503,7 @@ static inline int track_pfn_remap(struct vm_area_struct *vma, pgprot_t *prot,
  * by vmf_insert_pfn().
  */
 static inline void track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot,
-				    pfn_t pfn)
+				    unsigned long pfn)
 {
 }
 
@@ -1539,7 +1539,7 @@ extern int track_pfn_remap(struct vm_area_struct *vma, pgprot_t *prot,
 			   unsigned long pfn, unsigned long addr,
 			   unsigned long size);
 extern void track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot,
-			     pfn_t pfn);
+			     unsigned long pfn);
 extern int track_pfn_copy(struct vm_area_struct *vma);
 extern void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn,
 			unsigned long size, bool mm_wr_locked);
diff --git a/include/trace/events/fs_dax.h b/include/trace/events/fs_dax.h
index 86fe6ae..e188c71 100644
--- a/include/trace/events/fs_dax.h
+++ b/include/trace/events/fs_dax.h
@@ -127,7 +127,7 @@ DECLARE_EVENT_CLASS(dax_pmd_insert_mapping_class,
 		__entry->radix_entry = radix_entry;
 	),
 	TP_printk("dev %d:%d ino %#lx %s %s address %#lx length %#lx "
-			"pfn %#llx %s radix_entry %#lx",
+			"pfn %#llx radix_entry %#lx",
 		MAJOR(__entry->dev),
 		MINOR(__entry->dev),
 		__entry->ino,
@@ -135,9 +135,7 @@ DECLARE_EVENT_CLASS(dax_pmd_insert_mapping_class,
 		__entry->write ? "write" : "read",
 		__entry->address,
 		__entry->length,
-		__entry->pfn_val & ~PFN_FLAGS_MASK,
-		__print_flags_u64(__entry->pfn_val & PFN_FLAGS_MASK, "|",
-			PFN_FLAGS_TRACE),
+		__entry->pfn_val,
 		(unsigned long)__entry->radix_entry
 	)
 )
diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
index cf5ff92..a0e5d01 100644
--- a/mm/debug_vm_pgtable.c
+++ b/mm/debug_vm_pgtable.c
@@ -20,7 +20,6 @@
 #include <linux/mman.h>
 #include <linux/mm_types.h>
 #include <linux/module.h>
-#include <linux/pfn_t.h>
 #include <linux/printk.h>
 #include <linux/pgtable.h>
 #include <linux/random.h>
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 5e42a60..3626bf3 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -22,7 +22,6 @@
 #include <linux/mm_types.h>
 #include <linux/khugepaged.h>
 #include <linux/freezer.h>
-#include <linux/pfn_t.h>
 #include <linux/mman.h>
 #include <linux/memremap.h>
 #include <linux/pagemap.h>
@@ -1376,7 +1375,7 @@ vm_fault_t do_huge_pmd_anonymous_page(struct vm_fault *vmf)
 }
 
 static void insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr,
-		pmd_t *pmd, pfn_t pfn, pgprot_t prot, bool write,
+		pmd_t *pmd, unsigned long pfn, pgprot_t prot, bool write,
 		pgtable_t pgtable)
 {
 	struct mm_struct *mm = vma->vm_mm;
@@ -1384,7 +1383,7 @@ static void insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr,
 
 	if (!pmd_none(*pmd)) {
 		if (write) {
-			if (pmd_pfn(*pmd) != pfn_t_to_pfn(pfn)) {
+			if (pmd_pfn(*pmd) != pfn) {
 				WARN_ON_ONCE(!is_huge_zero_pmd(*pmd));
 				return;
 			}
@@ -1397,7 +1396,7 @@ static void insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr,
 		return;
 	}
 
-	entry = pmd_mkhuge(pfn_t_pmd(pfn, prot));
+	entry = pmd_mkhuge(pfn_pmd(pfn, prot));
 	entry = pmd_mkspecial(entry);
 	if (write) {
 		entry = pmd_mkyoung(pmd_mkdirty(entry));
@@ -1424,7 +1423,8 @@ static void insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr,
  *
  * Return: vm_fault_t value.
  */
-vm_fault_t vmf_insert_pfn_pmd(struct vm_fault *vmf, pfn_t pfn, bool write)
+vm_fault_t vmf_insert_pfn_pmd(struct vm_fault *vmf, unsigned long pfn,
+			      bool write)
 {
 	unsigned long addr = vmf->address & PMD_MASK;
 	struct vm_area_struct *vma = vmf->vma;
@@ -1487,7 +1487,7 @@ vm_fault_t vmf_insert_folio_pmd(struct vm_fault *vmf, struct folio *folio, bool 
 		folio_add_file_rmap_pmd(folio, &folio->page, vma);
 		add_mm_counter(mm, mm_counter_file(folio), HPAGE_PMD_NR);
 	}
-	insert_pfn_pmd(vma, addr, vmf->pmd, pfn_to_pfn_t(folio_pfn(folio)),
+	insert_pfn_pmd(vma, addr, vmf->pmd, folio_pfn(folio),
 		       vma->vm_page_prot, write, pgtable);
 	spin_unlock(ptl);
 	if (pgtable)
@@ -1506,7 +1506,7 @@ static pud_t maybe_pud_mkwrite(pud_t pud, struct vm_area_struct *vma)
 }
 
 static void insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr,
-		pud_t *pud, pfn_t pfn, bool write)
+		pud_t *pud, unsigned long pfn, bool write)
 {
 	struct mm_struct *mm = vma->vm_mm;
 	pgprot_t prot = vma->vm_page_prot;
@@ -1514,7 +1514,7 @@ static void insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr,
 
 	if (!pud_none(*pud)) {
 		if (write) {
-			if (WARN_ON_ONCE(pud_pfn(*pud) != pfn_t_to_pfn(pfn)))
+			if (WARN_ON_ONCE(pud_pfn(*pud) != pfn))
 				return;
 			entry = pud_mkyoung(*pud);
 			entry = maybe_pud_mkwrite(pud_mkdirty(entry), vma);
@@ -1524,7 +1524,7 @@ static void insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr,
 		return;
 	}
 
-	entry = pud_mkhuge(pfn_t_pud(pfn, prot));
+	entry = pud_mkhuge(pfn_pud(pfn, prot));
 	entry = pud_mkspecial(entry);
 	if (write) {
 		entry = pud_mkyoung(pud_mkdirty(entry));
@@ -1544,7 +1544,8 @@ static void insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr,
  *
  * Return: vm_fault_t value.
  */
-vm_fault_t vmf_insert_pfn_pud(struct vm_fault *vmf, pfn_t pfn, bool write)
+vm_fault_t vmf_insert_pfn_pud(struct vm_fault *vmf, unsigned long pfn,
+			      bool write)
 {
 	unsigned long addr = vmf->address & PUD_MASK;
 	struct vm_area_struct *vma = vmf->vma;
@@ -1601,7 +1602,7 @@ vm_fault_t vmf_insert_folio_pud(struct vm_fault *vmf, struct folio *folio, bool 
 		folio_add_file_rmap_pud(folio, &folio->page, vma);
 		add_mm_counter(mm, mm_counter_file(folio), HPAGE_PUD_NR);
 	}
-	insert_pfn_pud(vma, addr, vmf->pud, pfn_to_pfn_t(folio_pfn(folio)), write);
+	insert_pfn_pud(vma, addr, vmf->pud, folio_pfn(folio), write);
 	spin_unlock(ptl);
 
 	return VM_FAULT_NOPAGE;
diff --git a/mm/memory.c b/mm/memory.c
index 5f7a441..fef28de 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -57,7 +57,6 @@
 #include <linux/export.h>
 #include <linux/delayacct.h>
 #include <linux/init.h>
-#include <linux/pfn_t.h>
 #include <linux/writeback.h>
 #include <linux/memcontrol.h>
 #include <linux/mmu_notifier.h>
@@ -2406,7 +2405,7 @@ int vm_map_pages_zero(struct vm_area_struct *vma, struct page **pages,
 EXPORT_SYMBOL(vm_map_pages_zero);
 
 static vm_fault_t insert_pfn(struct vm_area_struct *vma, unsigned long addr,
-			pfn_t pfn, pgprot_t prot, bool mkwrite)
+			unsigned long pfn, pgprot_t prot, bool mkwrite)
 {
 	struct mm_struct *mm = vma->vm_mm;
 	pte_t *pte, entry;
@@ -2428,7 +2427,7 @@ static vm_fault_t insert_pfn(struct vm_area_struct *vma, unsigned long addr,
 			 * allocation and mapping invalidation so just skip the
 			 * update.
 			 */
-			if (pte_pfn(entry) != pfn_t_to_pfn(pfn)) {
+			if (pte_pfn(entry) != pfn) {
 				WARN_ON_ONCE(!is_zero_pfn(pte_pfn(entry)));
 				goto out_unlock;
 			}
@@ -2441,7 +2440,7 @@ static vm_fault_t insert_pfn(struct vm_area_struct *vma, unsigned long addr,
 	}
 
 	/* Ok, finally just insert the thing.. */
-	entry = pte_mkspecial(pfn_t_pte(pfn, prot));
+	entry = pte_mkspecial(pfn_pte(pfn, prot));
 
 	if (mkwrite) {
 		entry = pte_mkyoung(entry);
@@ -2510,10 +2509,9 @@ vm_fault_t vmf_insert_pfn_prot(struct vm_area_struct *vma, unsigned long addr,
 	if (!pfn_modify_allowed(pfn, pgprot))
 		return VM_FAULT_SIGBUS;
 
-	track_pfn_insert(vma, &pgprot, __pfn_to_pfn_t(pfn, 0));
+	track_pfn_insert(vma, &pgprot, pfn);
 
-	return insert_pfn(vma, addr, __pfn_to_pfn_t(pfn, 0), pgprot,
-			false);
+	return insert_pfn(vma, addr, pfn, pgprot, false);
 }
 EXPORT_SYMBOL(vmf_insert_pfn_prot);
 
@@ -2544,21 +2542,21 @@ vm_fault_t vmf_insert_pfn(struct vm_area_struct *vma, unsigned long addr,
 }
 EXPORT_SYMBOL(vmf_insert_pfn);
 
-static bool vm_mixed_ok(struct vm_area_struct *vma, pfn_t pfn, bool mkwrite)
+static bool vm_mixed_ok(struct vm_area_struct *vma, unsigned long pfn, bool mkwrite)
 {
-	if (unlikely(is_zero_pfn(pfn_t_to_pfn(pfn))) &&
+	if (unlikely(is_zero_pfn(pfn)) &&
 	    (mkwrite || !vm_mixed_zeropage_allowed(vma)))
 		return false;
 	/* these checks mirror the abort conditions in vm_normal_page */
 	if (vma->vm_flags & VM_MIXEDMAP)
 		return true;
-	if (is_zero_pfn(pfn_t_to_pfn(pfn)))
+	if (is_zero_pfn(pfn))
 		return true;
 	return false;
 }
 
 static vm_fault_t __vm_insert_mixed(struct vm_area_struct *vma,
-		unsigned long addr, pfn_t pfn, bool mkwrite)
+		unsigned long addr, unsigned long pfn, bool mkwrite)
 {
 	pgprot_t pgprot = vma->vm_page_prot;
 	int err;
@@ -2571,7 +2569,7 @@ static vm_fault_t __vm_insert_mixed(struct vm_area_struct *vma,
 
 	track_pfn_insert(vma, &pgprot, pfn);
 
-	if (!pfn_modify_allowed(pfn_t_to_pfn(pfn), pgprot))
+	if (!pfn_modify_allowed(pfn, pgprot))
 		return VM_FAULT_SIGBUS;
 
 	/*
@@ -2581,7 +2579,7 @@ static vm_fault_t __vm_insert_mixed(struct vm_area_struct *vma,
 	 * than insert_pfn).  If a zero_pfn were inserted into a VM_MIXEDMAP
 	 * without pte special, it would there be refcounted as a normal page.
 	 */
-	if (!IS_ENABLED(CONFIG_ARCH_HAS_PTE_SPECIAL) && pfn_t_valid(pfn)) {
+	if (!IS_ENABLED(CONFIG_ARCH_HAS_PTE_SPECIAL) && pfn_valid(pfn)) {
 		struct page *page;
 
 		/*
@@ -2589,7 +2587,7 @@ static vm_fault_t __vm_insert_mixed(struct vm_area_struct *vma,
 		 * regardless of whether the caller specified flags that
 		 * result in pfn_t_has_page() == false.
 		 */
-		page = pfn_to_page(pfn_t_to_pfn(pfn));
+		page = pfn_to_page(pfn);
 		err = insert_page(vma, addr, page, pgprot, mkwrite);
 	} else {
 		return insert_pfn(vma, addr, pfn, pgprot, mkwrite);
@@ -2615,7 +2613,7 @@ vm_fault_t vmf_insert_page_mkwrite(struct vm_fault *vmf, struct page *page,
 	if (addr < vma->vm_start || addr >= vma->vm_end)
 		return VM_FAULT_SIGBUS;
 
-	track_pfn_insert(vma, &pgprot, pfn_to_pfn_t(pfn));
+	track_pfn_insert(vma, &pgprot, pfn);
 
 	if (!pfn_modify_allowed(pfn, pgprot))
 		return VM_FAULT_SIGBUS;
@@ -2640,7 +2638,7 @@ vm_fault_t vmf_insert_page_mkwrite(struct vm_fault *vmf, struct page *page,
 EXPORT_SYMBOL_GPL(vmf_insert_page_mkwrite);
 
 vm_fault_t vmf_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
-		pfn_t pfn)
+		unsigned long pfn)
 {
 	return __vm_insert_mixed(vma, addr, pfn, false);
 }
@@ -2652,7 +2650,7 @@ EXPORT_SYMBOL(vmf_insert_mixed);
  *  the same entry was actually inserted.
  */
 vm_fault_t vmf_insert_mixed_mkwrite(struct vm_area_struct *vma,
-		unsigned long addr, pfn_t pfn)
+		unsigned long addr, unsigned long pfn)
 {
 	return __vm_insert_mixed(vma, addr, pfn, true);
 }
diff --git a/mm/memremap.c b/mm/memremap.c
index 6c13e72..0f007f4 100644
--- a/mm/memremap.c
+++ b/mm/memremap.c
@@ -5,7 +5,6 @@
 #include <linux/kasan.h>
 #include <linux/memory_hotplug.h>
 #include <linux/memremap.h>
-#include <linux/pfn_t.h>
 #include <linux/swap.h>
 #include <linux/mm.h>
 #include <linux/mmzone.h>
diff --git a/mm/migrate.c b/mm/migrate.c
index caadbe3..532591c 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -35,7 +35,6 @@
 #include <linux/compat.h>
 #include <linux/hugetlb.h>
 #include <linux/gfp.h>
-#include <linux/pfn_t.h>
 #include <linux/page_idle.h>
 #include <linux/page_owner.h>
 #include <linux/sched/mm.h>
diff --git a/tools/testing/nvdimm/pmem-dax.c b/tools/testing/nvdimm/pmem-dax.c
index c1ec099..05e763a 100644
--- a/tools/testing/nvdimm/pmem-dax.c
+++ b/tools/testing/nvdimm/pmem-dax.c
@@ -10,7 +10,7 @@
 
 long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff,
 		long nr_pages, enum dax_access_mode mode, void **kaddr,
-		pfn_t *pfn)
+		unsigned long *pfn)
 {
 	resource_size_t offset = PFN_PHYS(pgoff) + pmem->data_offset;
 
@@ -29,7 +29,7 @@ long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff,
 			*kaddr = pmem->virt_addr + offset;
 		page = vmalloc_to_page(pmem->virt_addr + offset);
 		if (pfn)
-			*pfn = page_to_pfn_t(page);
+			*pfn = page_to_pfn(page);
 		pr_debug_ratelimited("%s: pmem: %p pgoff: %#lx pfn: %#lx\n",
 				__func__, pmem, pgoff, page_to_pfn(page));
 
@@ -39,7 +39,7 @@ long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff,
 	if (kaddr)
 		*kaddr = pmem->virt_addr + offset;
 	if (pfn)
-		*pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags);
+		*pfn = PHYS_PFN(pmem->phys_addr + offset);
 
 	/*
 	 * If badblocks are present, limit known good range to the
diff --git a/tools/testing/nvdimm/test/iomap.c b/tools/testing/nvdimm/test/iomap.c
index ddceb04..f7e7bfe 100644
--- a/tools/testing/nvdimm/test/iomap.c
+++ b/tools/testing/nvdimm/test/iomap.c
@@ -8,7 +8,6 @@
 #include <linux/ioport.h>
 #include <linux/module.h>
 #include <linux/types.h>
-#include <linux/pfn_t.h>
 #include <linux/acpi.h>
 #include <linux/io.h>
 #include <linux/mm.h>
@@ -135,12 +134,6 @@ void *__wrap_devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
 }
 EXPORT_SYMBOL_GPL(__wrap_devm_memremap_pages);
 
-pfn_t __wrap_phys_to_pfn_t(phys_addr_t addr, unsigned long flags)
-{
-        return phys_to_pfn_t(addr, flags);
-}
-EXPORT_SYMBOL(__wrap_phys_to_pfn_t);
-
 void *__wrap_memremap(resource_size_t offset, size_t size,
 		unsigned long flags)
 {
-- 
git-series 0.9.1

[RFC 4/4] mm: Remove include/linux/pfn_t.h

[Alistair Popple]

None of the functionality in pfn_t.h is required so delete it.

Signed-off-by: Alistair Popple <apopple@nvidia.com>
---
 include/linux/pfn.h   | 10 +-----
 include/linux/pfn_t.h | 88 +--------------------------------------------
 2 files changed, 98 deletions(-)
 delete mode 100644 include/linux/pfn_t.h

diff --git a/include/linux/pfn.h b/include/linux/pfn.h
index 14bc053..f4a74d1 100644
--- a/include/linux/pfn.h
+++ b/include/linux/pfn.h
@@ -5,16 +5,6 @@
 #ifndef __ASSEMBLY__
 #include <linux/types.h>
 
-/*
- * pfn_t: encapsulates a page-frame number that is optionally backed
- * by memmap (struct page).  Whether a pfn_t has a 'struct page'
- * backing is indicated by flags in the high bits of the value.
- */
-typedef struct {
-	u64 val;
-} pfn_t;
-#endif
-
 #define PFN_ALIGN(x)	(((unsigned long)(x) + (PAGE_SIZE - 1)) & PAGE_MASK)
 #define PFN_UP(x)	(((x) + PAGE_SIZE-1) >> PAGE_SHIFT)
 #define PFN_DOWN(x)	((x) >> PAGE_SHIFT)
diff --git a/include/linux/pfn_t.h b/include/linux/pfn_t.h
deleted file mode 100644
index 034b5b0..0000000
--- a/include/linux/pfn_t.h
+++ /dev/null
@@ -1,88 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _LINUX_PFN_T_H_
-#define _LINUX_PFN_T_H_
-#include <linux/mm.h>
-
-/*
- * PFN_FLAGS_MASK - mask of all the possible valid pfn_t flags
- * PFN_SG_CHAIN - pfn is a pointer to the next scatterlist entry
- * PFN_SG_LAST - pfn references a page and is the last scatterlist entry
- * PFN_DEV - pfn is not covered by system memmap by default
- * PFN_MAP - pfn has a dynamic page mapping established by a device driver
- */
-#define PFN_FLAGS_MASK (((u64) (~PAGE_MASK)) << (BITS_PER_LONG_LONG - PAGE_SHIFT))
-
-#define PFN_FLAGS_TRACE { }
-
-static inline pfn_t __pfn_to_pfn_t(unsigned long pfn, u64 flags)
-{
-	pfn_t pfn_t = { .val = pfn | (flags & PFN_FLAGS_MASK), };
-
-	return pfn_t;
-}
-
-/* a default pfn to pfn_t conversion assumes that @pfn is pfn_valid() */
-static inline pfn_t pfn_to_pfn_t(unsigned long pfn)
-{
-	return __pfn_to_pfn_t(pfn, 0);
-}
-
-static inline pfn_t phys_to_pfn_t(phys_addr_t addr, u64 flags)
-{
-	return __pfn_to_pfn_t(addr >> PAGE_SHIFT, flags);
-}
-
-static inline bool pfn_t_has_page(pfn_t pfn)
-{
-	return (pfn.val & PFN_DEV) == 0;
-}
-
-static inline unsigned long pfn_t_to_pfn(pfn_t pfn)
-{
-	return pfn.val & ~PFN_FLAGS_MASK;
-}
-
-static inline struct page *pfn_t_to_page(pfn_t pfn)
-{
-	if (pfn_t_has_page(pfn))
-		return pfn_to_page(pfn_t_to_pfn(pfn));
-	return NULL;
-}
-
-static inline phys_addr_t pfn_t_to_phys(pfn_t pfn)
-{
-	return PFN_PHYS(pfn_t_to_pfn(pfn));
-}
-
-static inline pfn_t page_to_pfn_t(struct page *page)
-{
-	return pfn_to_pfn_t(page_to_pfn(page));
-}
-
-static inline int pfn_t_valid(pfn_t pfn)
-{
-	return pfn_valid(pfn_t_to_pfn(pfn));
-}
-
-#ifdef CONFIG_MMU
-static inline pte_t pfn_t_pte(pfn_t pfn, pgprot_t pgprot)
-{
-	return pfn_pte(pfn_t_to_pfn(pfn), pgprot);
-}
-#endif
-
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-static inline pmd_t pfn_t_pmd(pfn_t pfn, pgprot_t pgprot)
-{
-	return pfn_pmd(pfn_t_to_pfn(pfn), pgprot);
-}
-
-#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
-static inline pud_t pfn_t_pud(pfn_t pfn, pgprot_t pgprot)
-{
-	return pfn_pud(pfn_t_to_pfn(pfn), pgprot);
-}
-#endif
-#endif
-
-#endif /* _LINUX_PFN_T_H_ */
-- 
git-series 0.9.1

Re: [RFC 1/4] mm: Remove PFN_MAP, PFN_SG_CHAIN and PFN_SG_LAST

[Christoph Hellwig]

Looks good:

Reviewed-by: Christoph Hellwig <hch@lst.de>

Re: [RFC 2/4] mm: Remove uses of PFN_DEV

[Christoph Hellwig]

Looks good:

Reviewed-by: Christoph Hellwig <hch@lst.de>

Re: [RFC 3/4] mm: Remove callers of pfn_t functionality

[Christoph Hellwig]

On Wed, Jan 08, 2025 at 12:18:47PM +1100, Alistair Popple wrote:
> All PFN_* pfn_t flags have been removed. Therefore there is no longer
> a need for the pfn_t type and all uses can be replaced with normal
> pfns.

Looks good in general:

Reviewed-by: Christoph Hellwig <hch@lst.de>

Would be nice if you'd fix up the created overly long line everywhere
and not just in a few places, though.

Re: [RFC 4/4] mm: Remove include/linux/pfn_t.h

[Christoph Hellwig]

I'd just merge this into the previous patch, but otherwise this looks
good:

Reviewed-by: Christoph Hellwig <hch@lst.de>

Re: [RFC 0/4] mm: Remove pfn_t type

[Dan Williams]

Alistair Popple wrote:
> Once my series[1] and Dan's cleanup[2] is merged all users of DAX will
> require a ZONE_DEVICE page which is properly refcounted.  This means there
> is no longer any need for the PFN_DEV and PFN_MAP flags. Furthermore the
> PFN_SG_CHAIN and PFN_SG_LAST flags never appear to have been used. It is
> therefore possible to remove the pfn_t type and replace any usage with raw
> pfns.
> 
> The remaining users of PFN_DEV have simply passed this to
> vmf_insert_mixed(), however once my series is merged vmf_insert_mixed()
> doesn't need these flags anyway so those users can be trivially converted
> to using raw pfns.
> 
> Note that this RFC has only been lightly build tested. Also the third patch
> probably needs further splitting up. I have pushed a tree with this, along
> with the prerequisite series, to
> https://github.com/apopple/linux/tree/pfn_t_cleanup
> 
> [1] - https://lore.kernel.org/linux-mm/cover.425da7c4e76c2749d0ad1734f972b06114e02d52.1736221254.git-series.apopple@nvidia.com/
> [2] - https://lore.kernel.org/linux-mm/172721874675.497781.3277495908107141898.stgit@dwillia2-xfh.jf.intel.com/

For the series you can add:

Reviewed-by: Dan Williams <dan.j.williams@intel.com>


However, I expect that we need [2] at the top of your ZONE_DEVICE
series, because that conversion breaks FS_DAX_LIMITED. I see Andrew is
starting to pick this up so I'll go work that out with him.