Thread (140 messages) 140 messages, 10 authors, 12d ago
COOLING12d

[PATCH 16/30] mm/vma: use vma_start_pgoff(), linear_page_index() in mm code

From: Lorenzo Stoakes <ljs@kernel.org>
Date: 2026-06-29 12:24:43
Also in: damon, dri-devel, kvm, linux-arm-msm, linux-fsdevel, linux-iommu, linux-mm, linux-perf-users, linux-tegra, lkml, nvdimm
Subsystem: damon, exec & binfmt api, elf, hugetlb subsystem, memory management, memory management - core, memory management - memory policy and migration, memory management - misc, memory management - thp (transparent huge page), memory management - userfaultfd, memory mapping, memory mapping - madvise (memory advice), page cache, the rest, tmpfs (shmem filesystem) · Maintainers: SJ Park, Kees Cook, Muchun Song, Oscar Salvador, Andrew Morton, David Hildenbrand, Lorenzo Stoakes, Mike Rapoport, Liam R. Howlett, Matthew Wilcox, Jan Kara, Linus Torvalds, Hugh Dickins

There are many instances in which linear_page_index() (as well as
linear_page_delta()) is open-coded, which is confusing and inconsistent.

Additionally, vma->vm_pgoff doesn't necessarily make it clear that this is
the page offset of the start of the VMA range.

Doing so also aids greppability.

So use vma_start_pgoff() in favour of directly accessing vma->vm_pgoff, and
linear_page_index() where we can.

This also lays the ground for future changes which will add an anonymous
page offset in order to be able to index MAP_PRIVATE-file backed anon
folios in terms of their virtual page offset.

No functional change intended.

Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
---
 include/linux/huge_mm.h    |  1 +
 include/linux/hugetlb.h    |  3 +--
 include/linux/pagemap.h    |  2 +-
 mm/damon/vaddr.c           |  5 +++--
 mm/debug.c                 |  2 +-
 mm/filemap.c               |  7 ++++---
 mm/huge_memory.c           |  2 +-
 mm/hugetlb.c               | 11 ++++-------
 mm/internal.h              | 24 ++++++++++++++----------
 mm/khugepaged.c            |  3 ++-
 mm/madvise.c               |  6 +++---
 mm/mapping_dirty_helpers.c |  2 +-
 mm/memory.c                | 25 +++++++++++++------------
 mm/mempolicy.c             | 13 +++++++------
 mm/mremap.c                | 12 ++++--------
 mm/msync.c                 |  4 ++--
 mm/nommu.c                 |  7 ++++---
 mm/pagewalk.c              |  2 +-
 mm/shmem.c                 |  9 +++++----
 mm/userfaultfd.c           |  4 ++--
 mm/util.c                  |  4 ++--
 mm/vma.c                   | 15 +++++++--------
 mm/vma_exec.c              |  4 ++--
 mm/vma_init.c              |  2 +-
 24 files changed, 86 insertions(+), 83 deletions(-)
diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
index ad20f7f8c179..653b81d08fe7 100644
--- a/include/linux/huge_mm.h
+++ b/include/linux/huge_mm.h
@@ -230,6 +230,7 @@ static inline bool thp_vma_suitable_order(struct vm_area_struct *vma,
 
 	/* Don't have to check pgoff for anonymous vma */
 	if (!vma_is_anonymous(vma)) {
+		/* vma_start_pgoff() in mm.h so not available. */
 		if (!IS_ALIGNED((vma->vm_start >> PAGE_SHIFT) - vma->vm_pgoff,
 				hpage_size >> PAGE_SHIFT))
 			return false;
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 2abaf99321e9..8390f50604d6 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -792,8 +792,7 @@ static inline pgoff_t hugetlb_linear_page_index(struct vm_area_struct *vma,
 {
 	struct hstate *h = hstate_vma(vma);
 
-	return ((address - vma->vm_start) >> huge_page_shift(h)) +
-		(vma->vm_pgoff >> huge_page_order(h));
+	return linear_page_index(vma, address) >> huge_page_order(h);
 }
 
 static inline bool order_is_gigantic(unsigned int order)
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index 644c0f25ae73..68a88d34a468 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -1101,7 +1101,7 @@ static inline pgoff_t linear_page_index(const struct vm_area_struct *vma,
 	pgoff_t pgoff;
 
 	pgoff = linear_page_delta(vma, address);
-	pgoff += vma->vm_pgoff;
+	pgoff += vma_start_pgoff(vma);
 	return pgoff;
 }
 
diff --git a/mm/damon/vaddr.c b/mm/damon/vaddr.c
index d27147603564..faa44aa3219b 100644
--- a/mm/damon/vaddr.c
+++ b/mm/damon/vaddr.c
@@ -12,6 +12,7 @@
 #include <linux/mman.h>
 #include <linux/mmu_notifier.h>
 #include <linux/page_idle.h>
+#include <linux/pagemap.h>
 #include <linux/pagewalk.h>
 #include <linux/sched/mm.h>
 
@@ -627,8 +628,8 @@ static void damos_va_migrate_dests_add(struct folio *folio,
 	}
 
 	order = folio_order(folio);
-	ilx = vma->vm_pgoff >> order;
-	ilx += (addr - vma->vm_start) >> (PAGE_SHIFT + order);
+	ilx = vma_start_pgoff(vma) >> order;
+	ilx += linear_page_delta(vma, addr) >> order;
 
 	for (i = 0; i < dests->nr_dests; i++)
 		weight_total += dests->weight_arr[i];
diff --git a/mm/debug.c b/mm/debug.c
index 77fa8fe1d641..497654b36f1a 100644
--- a/mm/debug.c
+++ b/mm/debug.c
@@ -163,7 +163,7 @@ void dump_vma(const struct vm_area_struct *vma)
 		"flags: %#lx(%pGv)\n",
 		vma, (void *)vma->vm_start, (void *)vma->vm_end, vma->vm_mm,
 		(unsigned long)pgprot_val(vma->vm_page_prot),
-		vma->anon_vma, vma->vm_ops, vma->vm_pgoff,
+		vma->anon_vma, vma->vm_ops, vma_start_pgoff(vma),
 		vma->vm_file, vma->vm_private_data,
 #ifdef CONFIG_PER_VMA_LOCK
 		refcount_read(&vma->vm_refcnt),
diff --git a/mm/filemap.c b/mm/filemap.c
index 5af62e6abca5..bcb07b21a685 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -3402,8 +3402,8 @@ static struct file *do_sync_mmap_readahead(struct vm_fault *vmf)
 		 * of memory.
 		 */
 		struct vm_area_struct *vma = vmf->vma;
-		unsigned long start = vma->vm_pgoff;
-		unsigned long end = start + vma_pages(vma);
+		const unsigned long start = vma_start_pgoff(vma);
+		const unsigned long end = vma_end_pgoff(vma);
 		unsigned long ra_end;
 
 		ra->order = exec_folio_order();
@@ -3921,7 +3921,8 @@ vm_fault_t filemap_map_pages(struct vm_fault *vmf,
 		goto out;
 	}
 
-	addr = vma->vm_start + ((start_pgoff - vma->vm_pgoff) << PAGE_SHIFT);
+	addr = vma->vm_start +
+		((start_pgoff - vma_start_pgoff(vma)) << PAGE_SHIFT);
 	vmf->pte = pte_offset_map_lock(vma->vm_mm, vmf->pmd, addr, &vmf->ptl);
 	if (!vmf->pte) {
 		folio_unlock(folio);
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 2bccb0a53a0a..e94f56487225 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -180,7 +180,7 @@ unsigned long __thp_vma_allowable_orders(struct vm_area_struct *vma,
 	 */
 	if (!in_pf && shmem_file(vma->vm_file))
 		return orders & shmem_allowable_huge_orders(file_inode(vma->vm_file),
-						   vma, vma->vm_pgoff, 0,
+						   vma, vma_start_pgoff(vma), 0,
 						   forced_collapse);
 
 	if (!vma_is_anonymous(vma)) {
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index f45000149a78..d44a3ac5ee0a 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1011,8 +1011,7 @@ static long region_count(struct resv_map *resv, long f, long t)
 static pgoff_t vma_hugecache_offset(struct hstate *h,
 			struct vm_area_struct *vma, unsigned long address)
 {
-	return ((address - vma->vm_start) >> huge_page_shift(h)) +
-			(vma->vm_pgoff >> huge_page_order(h));
+	return linear_page_index(vma, address) >> huge_page_order(h);
 }
 
 /*
@@ -5372,8 +5371,7 @@ static void unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma,
 	 * from page cache lookup which is in HPAGE_SIZE units.
 	 */
 	address = address & huge_page_mask(h);
-	pgoff = ((address - vma->vm_start) >> PAGE_SHIFT) +
-			vma->vm_pgoff;
+	pgoff = linear_page_index(vma, address);
 	mapping = vma->vm_file->f_mapping;
 
 	/*
@@ -6771,7 +6769,7 @@ static unsigned long page_table_shareable(struct vm_area_struct *svma,
 				struct vm_area_struct *vma,
 				unsigned long addr, pgoff_t idx)
 {
-	unsigned long saddr = ((idx - svma->vm_pgoff) << PAGE_SHIFT) +
+	unsigned long saddr = ((idx - vma_start_pgoff(svma)) << PAGE_SHIFT) +
 				svma->vm_start;
 	unsigned long sbase = saddr & PUD_MASK;
 	unsigned long s_end = sbase + PUD_SIZE;
@@ -6856,8 +6854,7 @@ pte_t *huge_pmd_share(struct mm_struct *mm, struct vm_area_struct *vma,
 		      unsigned long addr, pud_t *pud)
 {
 	struct address_space *mapping = vma->vm_file->f_mapping;
-	pgoff_t idx = ((addr - vma->vm_start) >> PAGE_SHIFT) +
-			vma->vm_pgoff;
+	const pgoff_t idx = linear_page_index(vma, addr);
 	struct vm_area_struct *svma;
 	unsigned long saddr;
 	pte_t *spte = NULL;
diff --git a/mm/internal.h b/mm/internal.h
index 181e79f1d6a2..89e5b7efe256 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -1143,26 +1143,28 @@ static inline bool
 folio_within_range(struct folio *folio, struct vm_area_struct *vma,
 		unsigned long start, unsigned long end)
 {
-	pgoff_t pgoff, addr;
-	unsigned long vma_pglen = vma_pages(vma);
+	const unsigned long vma_pglen = vma_pages(vma);
+	pgoff_t pgoff_folio, pgoff_vma_start;
+	unsigned long addr;
 
 	VM_WARN_ON_FOLIO(folio_test_ksm(folio), folio);
 	if (start > end)
 		return false;
 
+	pgoff_folio = folio_pgoff(folio);
+	pgoff_vma_start = vma_start_pgoff(vma);
+
 	if (start < vma->vm_start)
 		start = vma->vm_start;
 
 	if (end > vma->vm_end)
 		end = vma->vm_end;
 
-	pgoff = folio_pgoff(folio);
-
 	/* if folio start address is not in vma range */
-	if (!in_range(pgoff, vma->vm_pgoff, vma_pglen))
+	if (!in_range(pgoff_folio, pgoff_vma_start, vma_pglen))
 		return false;
 
-	addr = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
+	addr = vma->vm_start + ((pgoff_folio - pgoff_vma_start) << PAGE_SHIFT);
 
 	return !(addr < start || end - addr < folio_size(folio));
 }
@@ -1234,15 +1236,16 @@ extern pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma);
 static inline unsigned long vma_address(const struct vm_area_struct *vma,
 		pgoff_t pgoff, unsigned long nr_pages)
 {
+	const pgoff_t pgoff_start = vma_start_pgoff(vma);
 	unsigned long address;
 
-	if (pgoff >= vma->vm_pgoff) {
+	if (pgoff >= pgoff_start) {
 		address = vma->vm_start +
-			((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
+			((pgoff - pgoff_start) << PAGE_SHIFT);
 		/* Check for address beyond vma (or wrapped through 0?) */
 		if (address < vma->vm_start || address >= vma->vm_end)
 			address = -EFAULT;
-	} else if (pgoff + nr_pages - 1 >= vma->vm_pgoff) {
+	} else if (pgoff + nr_pages - 1 >= pgoff_start) {
 		/* Test above avoids possibility of wrap to 0 on 32-bit */
 		address = vma->vm_start;
 	} else {
@@ -1266,7 +1269,8 @@ static inline unsigned long vma_address_end(struct page_vma_mapped_walk *pvmw)
 		return pvmw->address + PAGE_SIZE;
 
 	pgoff = pvmw->pgoff + pvmw->nr_pages;
-	address = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
+	address = vma->vm_start +
+		((pgoff - vma_start_pgoff(vma)) << PAGE_SHIFT);
 	/* Check for address beyond vma (or wrapped through 0?) */
 	if (address < vma->vm_start || address > vma->vm_end)
 		address = vma->vm_end;
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index bd5f86cf4bd8..ffef738d826c 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -2145,7 +2145,8 @@ static void retract_page_tables(struct address_space *mapping, pgoff_t pgoff)
 		spinlock_t *ptl;
 		bool success = false;
 
-		addr = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
+		addr = vma->vm_start +
+			((pgoff - vma_start_pgoff(vma)) << PAGE_SHIFT);
 		if (addr & ~HPAGE_PMD_MASK ||
 		    vma->vm_end < addr + HPAGE_PMD_SIZE)
 			continue;
diff --git a/mm/madvise.c b/mm/madvise.c
index cd9bb077072c..6730c4200a93 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -253,7 +253,7 @@ static void shmem_swapin_range(struct vm_area_struct *vma,
 			continue;
 
 		addr = vma->vm_start +
-			((xas.xa_index - vma->vm_pgoff) << PAGE_SHIFT);
+			((xas.xa_index - vma_start_pgoff(vma)) << PAGE_SHIFT);
 		xas_pause(&xas);
 		rcu_read_unlock();
 
@@ -318,7 +318,7 @@ static long madvise_willneed(struct madvise_behavior *madv_behavior)
 	mark_mmap_lock_dropped(madv_behavior);
 	get_file(file);
 	offset = (loff_t)(start - vma->vm_start)
-			+ ((loff_t)vma->vm_pgoff << PAGE_SHIFT);
+			+ ((loff_t)vma_start_pgoff(vma) << PAGE_SHIFT);
 	mmap_read_unlock(mm);
 	vfs_fadvise(file, offset, end - start, POSIX_FADV_WILLNEED);
 	fput(file);
@@ -1023,7 +1023,7 @@ static long madvise_remove(struct madvise_behavior *madv_behavior)
 		return -EACCES;
 
 	offset = (loff_t)(start - vma->vm_start)
-			+ ((loff_t)vma->vm_pgoff << PAGE_SHIFT);
+			+ ((loff_t)vma_start_pgoff(vma) << PAGE_SHIFT);
 
 	/*
 	 * Filesystem's fallocate may need to take i_rwsem.  We need to
diff --git a/mm/mapping_dirty_helpers.c b/mm/mapping_dirty_helpers.c
index 737c407f4081..e0efa36e0a07 100644
--- a/mm/mapping_dirty_helpers.c
+++ b/mm/mapping_dirty_helpers.c
@@ -95,7 +95,7 @@ static int clean_record_pte(pte_t *pte, unsigned long addr,
 
 	if (pte_dirty(ptent)) {
 		pgoff_t pgoff = ((addr - walk->vma->vm_start) >> PAGE_SHIFT) +
-			walk->vma->vm_pgoff - cwalk->bitmap_pgoff;
+			vma_start_pgoff(walk->vma) - cwalk->bitmap_pgoff;
 		pte_t old_pte = ptep_modify_prot_start(walk->vma, addr, pte);
 
 		ptent = pte_mkclean(old_pte);
diff --git a/mm/memory.c b/mm/memory.c
index 98c1a245f45a..f5eb06544ba4 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -725,10 +725,10 @@ static inline struct page *__vm_normal_page(struct vm_area_struct *vma,
 				if (!pfn_valid(pfn))
 					return NULL;
 			} else {
-				unsigned long off = (addr - vma->vm_start) >> PAGE_SHIFT;
+				const pgoff_t index = linear_page_index(vma, addr);
 
 				/* Only CoW'ed anon folios are "normal". */
-				if (pfn == vma->vm_pgoff + off)
+				if (pfn == index)
 					return NULL;
 				if (!is_cow_mapping(vma->vm_flags))
 					return NULL;
@@ -2643,7 +2643,7 @@ static int __vm_map_pages(struct vm_area_struct *vma, struct page **pages,
 int vm_map_pages(struct vm_area_struct *vma, struct page **pages,
 				unsigned long num)
 {
-	return __vm_map_pages(vma, pages, num, vma->vm_pgoff);
+	return __vm_map_pages(vma, pages, num, vma_start_pgoff(vma));
 }
 EXPORT_SYMBOL(vm_map_pages);
 
@@ -3298,7 +3298,8 @@ int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long
 	unsigned long pfn;
 	int err;
 
-	err = __simple_ioremap_prep(vm_len, vma->vm_pgoff, start, len, &pfn);
+	err = __simple_ioremap_prep(vm_len, vma_start_pgoff(vma), start, len,
+				    &pfn);
 	if (err)
 		return err;
 
@@ -4342,15 +4343,15 @@ static inline void unmap_mapping_range_tree(struct address_space *mapping,
 					    struct zap_details *details)
 {
 	struct vm_area_struct *vma;
-	unsigned long start, size;
 	struct mmu_gather tlb;
 
 	mapping_interval_tree_foreach(vma, mapping, first_index, last_index) {
-		const pgoff_t start_idx = max(first_index, vma->vm_pgoff);
+		const pgoff_t start_idx = max(first_index, vma_start_pgoff(vma));
 		const pgoff_t end_idx = min(last_index, vma_last_pgoff(vma)) + 1;
-
-		start = vma->vm_start + ((start_idx - vma->vm_pgoff) << PAGE_SHIFT);
-		size = (end_idx - start_idx) << PAGE_SHIFT;
+		const pgoff_t offset = start_idx - vma_start_pgoff(vma);
+		const unsigned long offset_bytes = offset << PAGE_SHIFT;
+		const unsigned long start = vma->vm_start + offset_bytes;
+		const unsigned long size = (end_idx - start_idx) << PAGE_SHIFT;
 
 		tlb_gather_mmu(&tlb, vma->vm_mm);
 		zap_vma_range_batched(&tlb, vma, start, size, details);
@@ -5684,7 +5685,7 @@ vm_fault_t finish_fault(struct vm_fault *vmf)
 	} else if (nr_pages > 1) {
 		pgoff_t idx = folio_page_idx(folio, page);
 		/* The page offset of vmf->address within the VMA. */
-		pgoff_t vma_off = vmf->pgoff - vmf->vma->vm_pgoff;
+		pgoff_t vma_off = vmf->pgoff - vma_start_pgoff(vmf->vma);
 		/* The index of the entry in the pagetable for fault page. */
 		pgoff_t pte_off = pte_index(vmf->address);
 
@@ -5796,7 +5797,7 @@ static vm_fault_t do_fault_around(struct vm_fault *vmf)
 	pgoff_t nr_pages = READ_ONCE(fault_around_pages);
 	pgoff_t pte_off = pte_index(vmf->address);
 	/* The page offset of vmf->address within the VMA. */
-	pgoff_t vma_off = vmf->pgoff - vmf->vma->vm_pgoff;
+	pgoff_t vma_off = vmf->pgoff - vma_start_pgoff(vmf->vma);
 	pgoff_t from_pte, to_pte;
 	vm_fault_t ret;
 
@@ -7274,7 +7275,7 @@ void print_vma_addr(char *prefix, unsigned long ip)
 	if (vma && vma->vm_file) {
 		struct file *f = vma->vm_file;
 		ip -= vma->vm_start;
-		ip += vma->vm_pgoff << PAGE_SHIFT;
+		ip += vma_start_pgoff(vma) << PAGE_SHIFT;
 		printk("%s%pD[%lx,%lx+%lx]", prefix, f, ip,
 				vma->vm_start,
 				vma->vm_end - vma->vm_start);
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 36699fabd3c2..650cdb23354a 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -2048,8 +2048,8 @@ struct mempolicy *get_vma_policy(struct vm_area_struct *vma,
 		pol = get_task_policy(current);
 	if (pol->mode == MPOL_INTERLEAVE ||
 	    pol->mode == MPOL_WEIGHTED_INTERLEAVE) {
-		*ilx += vma->vm_pgoff >> order;
-		*ilx += (addr - vma->vm_start) >> (PAGE_SHIFT + order);
+		*ilx += vma_start_pgoff(vma) >> order;
+		*ilx += linear_page_delta(vma, addr) >> order;
 	}
 	return pol;
 }
@@ -3250,16 +3250,17 @@ EXPORT_SYMBOL_FOR_MODULES(mpol_shared_policy_init, "kvm");
 int mpol_set_shared_policy(struct shared_policy *sp,
 			struct vm_area_struct *vma, struct mempolicy *pol)
 {
-	int err;
+	const pgoff_t pgoff = vma_start_pgoff(vma);
+	const pgoff_t pgoff_end = vma_end_pgoff(vma);
 	struct sp_node *new = NULL;
-	unsigned long sz = vma_pages(vma);
+	int err;
 
 	if (pol) {
-		new = sp_alloc(vma->vm_pgoff, vma->vm_pgoff + sz, pol);
+		new = sp_alloc(pgoff, pgoff_end, pol);
 		if (!new)
 			return -ENOMEM;
 	}
-	err = shared_policy_replace(sp, vma->vm_pgoff, vma->vm_pgoff + sz, new);
+	err = shared_policy_replace(sp, pgoff, pgoff_end, new);
 	if (err && new)
 		sp_free(new);
 	return err;
diff --git a/mm/mremap.c b/mm/mremap.c
index e9c8b1d05832..079a0ba0c4a7 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -948,8 +948,7 @@ static unsigned long vrm_set_new_addr(struct vma_remap_struct *vrm)
 	struct vm_area_struct *vma = vrm->vma;
 	unsigned long map_flags = 0;
 	/* Page Offset _into_ the VMA. */
-	pgoff_t internal_pgoff = (vrm->addr - vma->vm_start) >> PAGE_SHIFT;
-	pgoff_t pgoff = vma->vm_pgoff + internal_pgoff;
+	const pgoff_t pgoff = linear_page_index(vma, vrm->addr);
 	unsigned long new_addr = vrm_implies_new_addr(vrm) ? vrm->new_addr : 0;
 	unsigned long res;
 
@@ -1255,12 +1254,10 @@ static void unmap_source_vma(struct vma_remap_struct *vrm)
 static int copy_vma_and_data(struct vma_remap_struct *vrm,
 			     struct vm_area_struct **new_vma_ptr)
 {
-	unsigned long internal_offset = vrm->addr - vrm->vma->vm_start;
-	unsigned long internal_pgoff = internal_offset >> PAGE_SHIFT;
-	unsigned long new_pgoff = vrm->vma->vm_pgoff + internal_pgoff;
-	unsigned long moved_len;
+	const unsigned long new_pgoff = linear_page_index(vrm->vma, vrm->addr);
 	struct vm_area_struct *vma = vrm->vma;
 	struct vm_area_struct *new_vma;
+	unsigned long moved_len;
 	int err = 0;
 	PAGETABLE_MOVE(pmc, NULL, NULL, vrm->addr, vrm->new_addr, vrm->old_len);
 
@@ -1802,8 +1799,7 @@ static int check_prep_vma(struct vma_remap_struct *vrm)
 		vrm->populate_expand = true;
 
 	/* Need to be careful about a growing mapping */
-	pgoff = (addr - vma->vm_start) >> PAGE_SHIFT;
-	pgoff += vma->vm_pgoff;
+	pgoff = linear_page_index(vma, addr);
 	if (pgoff + (new_len >> PAGE_SHIFT) < pgoff)
 		return -EINVAL;
 
diff --git a/mm/msync.c b/mm/msync.c
index ac4c9bfea2e7..90b491a27a14 100644
--- a/mm/msync.c
+++ b/mm/msync.c
@@ -12,6 +12,7 @@
 #include <linux/mm.h>
 #include <linux/mman.h>
 #include <linux/file.h>
+#include <linux/pagemap.h>
 #include <linux/syscalls.h>
 #include <linux/sched.h>
 
@@ -85,8 +86,7 @@ SYSCALL_DEFINE3(msync, unsigned long, start, size_t, len, int, flags)
 			goto out_unlock;
 		}
 		file = vma->vm_file;
-		fstart = (start - vma->vm_start) +
-			 ((loff_t)vma->vm_pgoff << PAGE_SHIFT);
+		fstart = (loff_t)linear_page_index(vma, start) << PAGE_SHIFT;
 		fend = fstart + (min(end, vma->vm_end) - start) - 1;
 		start = vma->vm_end;
 		if ((flags & MS_SYNC) && file &&
diff --git a/mm/nommu.c b/mm/nommu.c
index 6d168f69763f..60560b2c457e 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -975,7 +975,7 @@ static int do_mmap_private(struct vm_area_struct *vma,
 		/* read the contents of a file into the copy */
 		loff_t fpos;
 
-		fpos = vma->vm_pgoff;
+		fpos = vma_start_pgoff(vma);
 		fpos <<= PAGE_SHIFT;
 
 		ret = kernel_read(vma->vm_file, base, len, &fpos);
@@ -1355,7 +1355,8 @@ static int split_vma(struct vma_iterator *vmi, struct vm_area_struct *vma,
 	delete_nommu_region(vma->vm_region);
 	if (new_below) {
 		vma->vm_region->vm_start = vma->vm_start = addr;
-		vma->vm_region->vm_pgoff = vma->vm_pgoff += npages;
+		vma->vm_pgoff += npages;
+		vma->vm_region->vm_pgoff = vma_start_pgoff(vma);
 	} else {
 		vma->vm_region->vm_end = vma->vm_end = addr;
 		vma->vm_region->vm_top = addr;
@@ -1603,7 +1604,7 @@ int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long
 	unsigned long pfn = start >> PAGE_SHIFT;
 	unsigned long vm_len = vma->vm_end - vma->vm_start;
 
-	pfn += vma->vm_pgoff;
+	pfn += vma_start_pgoff(vma);
 	return io_remap_pfn_range(vma, vma->vm_start, pfn, vm_len, vma->vm_page_prot);
 }
 EXPORT_SYMBOL(vm_iomap_memory);
diff --git a/mm/pagewalk.c b/mm/pagewalk.c
index 98d090ede077..0a3bbff57d46 100644
--- a/mm/pagewalk.c
+++ b/mm/pagewalk.c
@@ -813,7 +813,7 @@ int walk_page_mapping(struct address_space *mapping, pgoff_t first_index,
 	mapping_interval_tree_foreach(vma, mapping, first_index,
 				      first_index + nr - 1) {
 		/* Clip to the vma */
-		vba = vma->vm_pgoff;
+		vba = vma_start_pgoff(vma);
 		vea = vba + vma_pages(vma);
 		cba = first_index;
 		cba = max(cba, vba);
diff --git a/mm/shmem.c b/mm/shmem.c
index b51f83c970bb..4e7f6bc7a389 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1032,6 +1032,8 @@ unsigned long shmem_swap_usage(struct vm_area_struct *vma)
 	struct inode *inode = file_inode(vma->vm_file);
 	struct shmem_inode_info *info = SHMEM_I(inode);
 	struct address_space *mapping = inode->i_mapping;
+	const pgoff_t pgoff = vma_start_pgoff(vma);
+	const pgoff_t pgoff_end = vma_end_pgoff(vma);
 	unsigned long swapped;
 
 	/* Be careful as we don't hold info->lock */
@@ -1045,12 +1047,11 @@ unsigned long shmem_swap_usage(struct vm_area_struct *vma)
 	if (!swapped)
 		return 0;
 
-	if (!vma->vm_pgoff && vma->vm_end - vma->vm_start >= inode->i_size)
+	if (!pgoff && vma->vm_end - vma->vm_start >= inode->i_size)
 		return swapped << PAGE_SHIFT;
 
 	/* Here comes the more involved part */
-	return shmem_partial_swap_usage(mapping, vma->vm_pgoff,
-					vma->vm_pgoff + vma_pages(vma));
+	return shmem_partial_swap_usage(mapping, pgoff, pgoff_end);
 }
 
 /*
@@ -2839,7 +2840,7 @@ static struct mempolicy *shmem_get_policy(struct vm_area_struct *vma,
 	 * by page order, as in shmem_get_pgoff_policy() and get_vma_policy()).
 	 */
 	*ilx = inode->i_ino;
-	index = ((addr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
+	index = linear_page_index(vma, addr);
 	return mpol_shared_policy_lookup(&SHMEM_I(inode)->policy, index);
 }
 
diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c
index 246af12bf801..bf4518f4449d 100644
--- a/mm/userfaultfd.c
+++ b/mm/userfaultfd.c
@@ -481,7 +481,7 @@ static void mfill_retry_state_save(struct mfill_retry_state *s,
 {
 	s->flags = vma_flags_and_mask(&vma->flags, MFILL_RETRY_STATE_VMA_FLAGS);
 	s->ops = vma_uffd_ops(vma);
-	s->pgoff = vma->vm_pgoff;
+	s->pgoff = vma_start_pgoff(vma);
 
 	if (vma->vm_file)
 		s->file = get_file(vma->vm_file);
@@ -507,7 +507,7 @@ static bool mfill_retry_state_changed(struct mfill_retry_state *state,
 
 	/* VMA was file backed, but file, inode or offset has changed */
 	if (!vma->vm_file || vma->vm_file->f_inode != state->file->f_inode ||
-	    state->file != vma->vm_file || vma->vm_pgoff != state->pgoff)
+	    state->file != vma->vm_file || vma_start_pgoff(vma) != state->pgoff)
 		return true;
 
 	return false;
diff --git a/mm/util.c b/mm/util.c
index af2c2103f0d9..61e6d32b2c16 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -1188,7 +1188,7 @@ void compat_set_desc_from_vma(struct vm_area_desc *desc,
 	desc->start = vma->vm_start;
 	desc->end = vma->vm_end;
 
-	desc->pgoff = vma->vm_pgoff;
+	desc->pgoff = vma_start_pgoff(vma);
 	desc->vm_file = vma->vm_file;
 	desc->vma_flags = vma->flags;
 	desc->page_prot = vma->vm_page_prot;
@@ -1379,7 +1379,7 @@ static int call_vma_mapped(struct vm_area_struct *vma)
 	if (!vm_ops || !vm_ops->mapped)
 		return 0;
 
-	err = vm_ops->mapped(vma->vm_start, vma->vm_end, vma->vm_pgoff,
+	err = vm_ops->mapped(vma->vm_start, vma->vm_end, vma_start_pgoff(vma),
 			     vma->vm_file, &vm_private_data);
 	if (err)
 		return err;
diff --git a/mm/vma.c b/mm/vma.c
index dc4c2c1077f4..ee3a8ca13d07 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -967,10 +967,9 @@ static __must_check struct vm_area_struct *vma_merge_existing_range(
 		 *   prev   middle   next
 		 *  extend  delete  delete
 		 */
-
 		vmg->start = prev->vm_start;
 		vmg->end = next->vm_end;
-		vmg->pgoff = prev->vm_pgoff;
+		vmg->pgoff = vma_start_pgoff(prev);
 
 		/*
 		 * We already ensured anon_vma compatibility above, so now it's
@@ -987,9 +986,8 @@ static __must_check struct vm_area_struct *vma_merge_existing_range(
 		 *   prev     middle
 		 *  extend shrink/delete
 		 */
-
 		vmg->start = prev->vm_start;
-		vmg->pgoff = prev->vm_pgoff;
+		vmg->pgoff = vma_start_pgoff(prev);
 
 		if (!vmg->__remove_middle)
 			vmg->__adjust_middle_start = true;
@@ -1011,13 +1009,13 @@ static __must_check struct vm_area_struct *vma_merge_existing_range(
 
 		if (vmg->__remove_middle) {
 			vmg->end = next->vm_end;
-			vmg->pgoff = next->vm_pgoff - pglen;
+			vmg->pgoff = vma_start_pgoff(next) - pglen;
 		} else {
 			/* We shrink middle and expand next. */
 			vmg->__adjust_next_start = true;
 			vmg->start = middle->vm_start;
 			vmg->end = start;
-			vmg->pgoff = middle->vm_pgoff;
+			vmg->pgoff = vma_start_pgoff(middle);
 		}
 
 		err = dup_anon_vma(next, middle, &anon_dup);
@@ -1126,7 +1124,7 @@ struct vm_area_struct *vma_merge_new_range(struct vma_merge_struct *vmg)
 	if (can_merge_left) {
 		vmg->start = prev->vm_start;
 		vmg->target = prev;
-		vmg->pgoff = prev->vm_pgoff;
+		vmg->pgoff = vma_start_pgoff(prev);
 
 		/*
 		 * If this merge would result in removal of the next VMA but we
@@ -1957,7 +1955,8 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap,
 			VM_BUG_ON_VMA(faulted_in_anon_vma, new_vma);
 			*vmap = vma = new_vma;
 		}
-		*need_rmap_locks = (new_vma->vm_pgoff <= vma->vm_pgoff);
+		*need_rmap_locks =
+			(vma_start_pgoff(new_vma) <= vma_start_pgoff(vma));
 	} else {
 		new_vma = vm_area_dup(vma);
 		if (!new_vma)
diff --git a/mm/vma_exec.c b/mm/vma_exec.c
index 5cee8b7efa0f..e3644a3042e2 100644
--- a/mm/vma_exec.c
+++ b/mm/vma_exec.c
@@ -37,7 +37,7 @@ int relocate_vma_down(struct vm_area_struct *vma, unsigned long shift)
 	unsigned long new_end = old_end - shift;
 	VMA_ITERATOR(vmi, mm, new_start);
 	VMG_STATE(vmg, mm, &vmi, new_start, old_end, EMPTY_VMA_FLAGS,
-		  vma->vm_pgoff);
+		  vma_start_pgoff(vma));
 	struct vm_area_struct *next;
 	struct mmu_gather tlb;
 	PAGETABLE_MOVE(pmc, vma, vma, old_start, new_start, length);
@@ -89,7 +89,7 @@ int relocate_vma_down(struct vm_area_struct *vma, unsigned long shift)
 
 	vma_prev(&vmi);
 	/* Shrink the vma to just the new range */
-	return vma_shrink(&vmi, vma, new_start, new_end, vma->vm_pgoff);
+	return vma_shrink(&vmi, vma, new_start, new_end, vma_start_pgoff(vma));
 }
 
 /*
diff --git a/mm/vma_init.c b/mm/vma_init.c
index 3c0b65950510..a459669a1654 100644
--- a/mm/vma_init.c
+++ b/mm/vma_init.c
@@ -46,7 +46,7 @@ static void vm_area_init_from(const struct vm_area_struct *src,
 	dest->vm_start = src->vm_start;
 	dest->vm_end = src->vm_end;
 	dest->anon_vma = src->anon_vma;
-	dest->vm_pgoff = src->vm_pgoff;
+	dest->vm_pgoff = vma_start_pgoff(src);
 	dest->vm_file = src->vm_file;
 	dest->vm_private_data = src->vm_private_data;
 	vm_flags_init(dest, src->vm_flags);
-- 
2.54.0
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