+ mm-prefer-vma__pgoff-to-vma-vm_pgoff-in-kernel.patch added to mm-new branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: mm: prefer vma_[start,end]_pgoff() to vma->vm_pgoff in kernel/
has been added to the -mm mm-new branch.  Its filename is
     mm-prefer-vma__pgoff-to-vma-vm_pgoff-in-kernel.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-prefer-vma__pgoff-to-vma-vm_pgoff-in-kernel.patch

This patch will later appear in the mm-new branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Note, mm-new is a provisional staging ground for work-in-progress
patches, and acceptance into mm-new is a notification for others take
notice and to finish up reviews.  Please do not hesitate to respond to
review feedback and post updated versions to replace or incrementally
fixup patches in mm-new.

The mm-new branch of mm.git is not included in linux-next

If a few days of testing in mm-new is successful, the patch will me moved
into mm.git's mm-unstable branch, which is included in linux-next

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*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***

The -mm tree is included into linux-next via various
branches at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there most days

------------------------------------------------------
From: Lorenzo Stoakes <ljs@kernel.org>
Subject: mm: prefer vma_[start,end]_pgoff() to vma->vm_pgoff in kernel/
Date: Fri, 10 Jul 2026 21:17:00 +0100

Be consistent in using vma_start_pgoff() and vma_end_pgoff(), which clearly
indicates which part of the VMA the page offset refers to and aids
greppability.

This is part of a broader series laying the ground to provide a virtual
page offset for MAP_PRIVATE-file backed anon folios.

No functional change intended.

Link: https://lore.kernel.org/20260710-b4-pre-scalable-cow-v2-19-2a5aa403d977@kernel.org
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> # for kernel/dma
Reviewed-by: Gregory Price <gourry@gourry.net>
Acked-by: Pedro Falcato <pfalcato@suse.de>
Cc: Ackerley Tng <ackerleytng@google.com>
Cc: David Hildenbrand (Arm) <david@kernel.org>
Cc: Kai Huang <kai.huang@intel.com>
Cc: SJ Park <sj@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 kernel/dma/coherent.c      |    7 ++++---
 kernel/dma/direct.c        |    6 ++++--
 kernel/dma/mapping.c       |    8 +++++---
 kernel/dma/ops_helpers.c   |    4 ++--
 kernel/events/core.c       |   20 +++++++++++---------
 kernel/events/uprobes.c    |   11 +++++++----
 kernel/kcov.c              |    2 +-
 kernel/trace/ring_buffer.c |    3 ++-
 8 files changed, 36 insertions(+), 25 deletions(-)

--- a/kernel/dma/coherent.c~mm-prefer-vma__pgoff-to-vma-vm_pgoff-in-kernel
+++ a/kernel/dma/coherent.c
@@ -236,14 +236,15 @@ static int __dma_mmap_from_coherent(stru
 {
 	if (mem && vaddr >= mem->virt_base && vaddr + size <=
 		   (mem->virt_base + ((dma_addr_t)mem->size << PAGE_SHIFT))) {
-		unsigned long off = vma->vm_pgoff;
+		const pgoff_t pgoff_start = vma_start_pgoff(vma);
+		const pgoff_t pgoff_end = vma_end_pgoff(vma);
 		int start = (vaddr - mem->virt_base) >> PAGE_SHIFT;
 		unsigned long user_count = vma_pages(vma);
 		int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
 
 		*ret = -ENXIO;
-		if (off < count && user_count <= count - off) {
-			unsigned long pfn = mem->pfn_base + start + off;
+		if (pgoff_start < count && pgoff_end <= count) {
+			unsigned long pfn = mem->pfn_base + start + pgoff_start;
 			*ret = remap_pfn_range(vma, vma->vm_start, pfn,
 					       user_count << PAGE_SHIFT,
 					       vma->vm_page_prot);
--- a/kernel/dma/direct.c~mm-prefer-vma__pgoff-to-vma-vm_pgoff-in-kernel
+++ a/kernel/dma/direct.c
@@ -534,6 +534,8 @@ int dma_direct_mmap(struct device *dev,
 	unsigned long user_count = vma_pages(vma);
 	unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
 	unsigned long pfn = PHYS_PFN(dma_to_phys(dev, dma_addr));
+	const pgoff_t pgoff_start = vma_start_pgoff(vma);
+	const pgoff_t pgoff_end = vma_end_pgoff(vma);
 	int ret = -ENXIO;
 
 	vma->vm_page_prot = dma_pgprot(dev, vma->vm_page_prot, attrs);
@@ -545,9 +547,9 @@ int dma_direct_mmap(struct device *dev,
 	if (dma_mmap_from_global_coherent(vma, cpu_addr, size, &ret))
 		return ret;
 
-	if (vma->vm_pgoff >= count || user_count > count - vma->vm_pgoff)
+	if (pgoff_start >= count || pgoff_end > count)
 		return -ENXIO;
-	return remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff,
+	return remap_pfn_range(vma, vma->vm_start, pfn + pgoff_start,
 			user_count << PAGE_SHIFT, vma->vm_page_prot);
 }
 
--- a/kernel/dma/mapping.c~mm-prefer-vma__pgoff-to-vma-vm_pgoff-in-kernel
+++ a/kernel/dma/mapping.c
@@ -761,12 +761,14 @@ EXPORT_SYMBOL_GPL(dma_free_pages);
 int dma_mmap_pages(struct device *dev, struct vm_area_struct *vma,
 		size_t size, struct page *page)
 {
-	unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
+	const pgoff_t pgoff_start = vma_start_pgoff(vma);
+	const pgoff_t pgoff_end = vma_end_pgoff(vma);
+	const unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
 
-	if (vma->vm_pgoff >= count || vma_pages(vma) > count - vma->vm_pgoff)
+	if (pgoff_start >= count || pgoff_end > count)
 		return -ENXIO;
 	return remap_pfn_range(vma, vma->vm_start,
-			       page_to_pfn(page) + vma->vm_pgoff,
+			       page_to_pfn(page) + pgoff_start,
 			       vma_pages(vma) << PAGE_SHIFT, vma->vm_page_prot);
 }
 EXPORT_SYMBOL_GPL(dma_mmap_pages);
--- a/kernel/dma/ops_helpers.c~mm-prefer-vma__pgoff-to-vma-vm_pgoff-in-kernel
+++ a/kernel/dma/ops_helpers.c
@@ -39,7 +39,7 @@ int dma_common_mmap(struct device *dev,
 #ifdef CONFIG_MMU
 	unsigned long user_count = vma_pages(vma);
 	unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
-	unsigned long off = vma->vm_pgoff;
+	unsigned long off = vma_start_pgoff(vma);
 	struct page *page = dma_common_vaddr_to_page(cpu_addr);
 	int ret = -ENXIO;
 
@@ -52,7 +52,7 @@ int dma_common_mmap(struct device *dev,
 		return -ENXIO;
 
 	return remap_pfn_range(vma, vma->vm_start,
-			page_to_pfn(page) + vma->vm_pgoff,
+			page_to_pfn(page) + vma_start_pgoff(vma),
 			user_count << PAGE_SHIFT, vma->vm_page_prot);
 #else
 	return -ENXIO;
--- a/kernel/events/core.c~mm-prefer-vma__pgoff-to-vma-vm_pgoff-in-kernel
+++ a/kernel/events/core.c
@@ -6998,7 +6998,7 @@ static void perf_mmap_open(struct vm_are
 	refcount_inc(&event->mmap_count);
 	refcount_inc(&event->rb->mmap_count);
 
-	if (vma->vm_pgoff)
+	if (vma_start_pgoff(vma))
 		refcount_inc(&event->rb->aux_mmap_count);
 
 	if (mapped)
@@ -7032,7 +7032,7 @@ static void perf_mmap_close(struct vm_ar
 	 * The AUX buffer is strictly a sub-buffer, serialize using aux_mutex
 	 * to avoid complications.
 	 */
-	if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff &&
+	if (rb_has_aux(rb) && vma_start_pgoff(vma) == rb->aux_pgoff &&
 	    refcount_dec_and_mutex_lock(&rb->aux_mmap_count, &rb->aux_mutex)) {
 		/*
 		 * Stop all AUX events that are writing to this buffer,
@@ -7190,7 +7190,8 @@ static int map_range(struct perf_buffer
 	 */
 	for (pagenum = 0; pagenum < nr_pages; pagenum++) {
 		unsigned long va = vma->vm_start + PAGE_SIZE * pagenum;
-		struct page *page = perf_mmap_to_page(rb, vma->vm_pgoff + pagenum);
+		struct page *page = perf_mmap_to_page(rb,
+				vma_start_pgoff(vma) + pagenum);
 
 		if (page == NULL) {
 			err = -EINVAL;
@@ -7344,6 +7345,7 @@ static int perf_mmap_rb(struct vm_area_s
 static int perf_mmap_aux(struct vm_area_struct *vma, struct perf_event *event,
 			 unsigned long nr_pages)
 {
+	const pgoff_t pgoff_start = vma_start_pgoff(vma);
 	long extra = 0, user_extra = nr_pages;
 	u64 aux_offset, aux_size;
 	struct perf_buffer *rb;
@@ -7366,11 +7368,11 @@ static int perf_mmap_aux(struct vm_area_
 	if (aux_offset < perf_data_size(rb) + PAGE_SIZE)
 		return -EINVAL;
 
-	if (aux_offset != vma->vm_pgoff << PAGE_SHIFT)
+	if (aux_offset != pgoff_start << PAGE_SHIFT)
 		return -EINVAL;
 
 	/* already mapped with a different offset */
-	if (rb_has_aux(rb) && rb->aux_pgoff != vma->vm_pgoff)
+	if (rb_has_aux(rb) && rb->aux_pgoff != pgoff_start)
 		return -EINVAL;
 
 	if (aux_size != nr_pages * PAGE_SIZE)
@@ -7400,7 +7402,7 @@ static int perf_mmap_aux(struct vm_area_
 		if (vma->vm_flags & VM_WRITE)
 			rb_flags |= RING_BUFFER_WRITABLE;
 
-		ret = rb_alloc_aux(rb, event, vma->vm_pgoff, nr_pages,
+		ret = rb_alloc_aux(rb, event, pgoff_start, nr_pages,
 				   event->attr.aux_watermark, rb_flags);
 		if (ret) {
 			refcount_dec(&rb->mmap_count);
@@ -7457,7 +7459,7 @@ static int perf_mmap(struct file *file,
 		if (event->state <= PERF_EVENT_STATE_REVOKED)
 			return -ENODEV;
 
-		if (vma->vm_pgoff == 0)
+		if (!vma_start_pgoff(vma))
 			ret = perf_mmap_rb(vma, event, nr_pages);
 		else
 			ret = perf_mmap_aux(vma, event, nr_pages);
@@ -9884,7 +9886,7 @@ static bool perf_addr_filter_vma_adjust(
 					struct perf_addr_filter_range *fr)
 {
 	unsigned long vma_size = vma->vm_end - vma->vm_start;
-	unsigned long off = vma->vm_pgoff << PAGE_SHIFT;
+	unsigned long off = vma_start_pgoff(vma) << PAGE_SHIFT;
 	struct file *file = vma->vm_file;
 
 	if (!perf_addr_filter_match(filter, file, off, vma_size))
@@ -9974,7 +9976,7 @@ void perf_event_mmap(struct vm_area_stru
 			/* .tid */
 			.start  = vma->vm_start,
 			.len    = vma->vm_end - vma->vm_start,
-			.pgoff  = (u64)vma->vm_pgoff << PAGE_SHIFT,
+			.pgoff  = (u64)vma_start_pgoff(vma) << PAGE_SHIFT,
 		},
 		/* .maj (attr_mmap2 only) */
 		/* .min (attr_mmap2 only) */
--- a/kernel/events/uprobes.c~mm-prefer-vma__pgoff-to-vma-vm_pgoff-in-kernel
+++ a/kernel/events/uprobes.c
@@ -144,12 +144,14 @@ static bool valid_vma(struct vm_area_str
 
 static unsigned long offset_to_vaddr(struct vm_area_struct *vma, loff_t offset)
 {
-	return vma->vm_start + offset - ((loff_t)vma->vm_pgoff << PAGE_SHIFT);
+	return vma->vm_start + offset -
+		((loff_t)vma_start_pgoff(vma) << PAGE_SHIFT);
 }
 
 static loff_t vaddr_to_offset(struct vm_area_struct *vma, unsigned long vaddr)
 {
-	return ((loff_t)vma->vm_pgoff << PAGE_SHIFT) + (vaddr - vma->vm_start);
+	return ((loff_t)vma_start_pgoff(vma) << PAGE_SHIFT) +
+		(vaddr - vma->vm_start);
 }
 
 /**
@@ -1482,7 +1484,7 @@ static int unapply_uprobe(struct uprobe
 		    file_inode(vma->vm_file) != uprobe->inode)
 			continue;
 
-		offset = (loff_t)vma->vm_pgoff << PAGE_SHIFT;
+		offset = (loff_t)vma_start_pgoff(vma) << PAGE_SHIFT;
 		if (uprobe->offset <  offset ||
 		    uprobe->offset >= offset + vma->vm_end - vma->vm_start)
 			continue;
@@ -2453,7 +2455,8 @@ static struct uprobe *find_active_uprobe
 	if (!vm_file)
 		return NULL;
 
-	offset = (loff_t)(vma->vm_pgoff << PAGE_SHIFT) + (bp_vaddr - vma->vm_start);
+	offset = (loff_t)(vma_start_pgoff(vma) << PAGE_SHIFT) +
+		(bp_vaddr - vma->vm_start);
 	uprobe = find_uprobe_rcu(vm_file->f_inode, offset);
 	if (!uprobe)
 		return NULL;
--- a/kernel/kcov.c~mm-prefer-vma__pgoff-to-vma-vm_pgoff-in-kernel
+++ a/kernel/kcov.c
@@ -512,7 +512,7 @@ static int kcov_mmap(struct file *filep,
 
 	spin_lock_irqsave(&kcov->lock, flags);
 	size = kcov->size * sizeof(unsigned long);
-	if (kcov->area == NULL || vma->vm_pgoff != 0 ||
+	if (kcov->area == NULL || vma_start_pgoff(vma) ||
 	    vma->vm_end - vma->vm_start != size) {
 		res = -EINVAL;
 		goto exit;
--- a/kernel/trace/ring_buffer.c~mm-prefer-vma__pgoff-to-vma-vm_pgoff-in-kernel
+++ a/kernel/trace/ring_buffer.c
@@ -7613,7 +7613,8 @@ static int __rb_inc_dec_mapped(struct ri
 static int __rb_map_vma(struct ring_buffer_per_cpu *cpu_buffer,
 			struct vm_area_struct *vma)
 {
-	unsigned long nr_subbufs, nr_pages, nr_vma_pages, pgoff = vma->vm_pgoff;
+	unsigned long nr_subbufs, nr_pages, nr_vma_pages;
+	pgoff_t pgoff = vma_start_pgoff(vma);
 	unsigned int subbuf_pages, subbuf_order;
 	struct page **pages __free(kfree) = NULL;
 	int p = 0, s = 0;
_

Patches currently in -mm which might be from ljs@kernel.org are

mm-move-alloc-tag-to-mm.patch
mm-ptdump-always-stabilise-against-page-table-freeing-using-init_mm.patch
mm-vmalloc-acquire-init_mm-read-lock-on-huge-vmap-promotion.patch
revert-arm64-enable-vmalloc-huge-with-ptdump.patch
mm-move-vma_start_pgoff-into-mmh-and-clean-up.patch
mm-add-kdoc-comments-for-vma_start-last_pgoff.patch
tools-testing-vma-use-vma_start_pgoff-in-merge-tests.patch
mm-introduce-and-use-vma_end_pgoff.patch
mm-rmap-update-mm-interval_treec-comments.patch
mm-rmap-parameterise-vma_interval_tree_-by-address_space.patch
mm-rmap-elide-unnecessary-static-inlines-in-interval_treec.patch
mm-rmap-rename-vma_interval_tree_-to-mapping_rmap_tree_.patch
mm-rmap-parameterise-anon_vma_interval_tree_-by-anon_vma.patch
mm-rmap-rename-anon_vma_interval_tree_-params-and-use-pgoff_t.patch
mm-rmap-rename-anon_vma_interval_tree_-to-anon_rmap_tree_.patch
maintainers-move-mm-interval_treec-to-rmap-section.patch
mm-vma-introduce-and-use-vmg_pages-vmg__pgoff.patch
mm-vma-clean-up-anon_vma_compatible.patch
mm-vma-refactor-vmg_adjust_set_range-for-clarity.patch
mm-vma-minor-cleanup-of-expand_.patch
mm-introduce-and-use-linear_page_delta.patch
mm-vma-use-vma_start_pgoff-linear_page_index-in-mm-code.patch
mm-prefer-vma__pgoff-to-vma-vm_pgoff-in-kernel.patch
mm-vma-remove-duplicative-vma_pgoff_offset-helper.patch
mm-use-linear_page_-consistently.patch
mm-vma-introduce-vma_assert_can_modify.patch
mm-vma-add-and-use-vma__pgoff.patch
mm-vma-move-__install_special_mapping-to-vmac.patch
mm-vma-make-vma_set_range-static-drop-insert_vm_struct-decl.patch
mm-vma-update-vma_shrink-to-not-pass-start-pgoff-parameters.patch
mm-vma-update-vmg_adjust_set_range-to-offset-pgoff-instead.patch
mm-vma-slightly-rework-the-anonymous-check-in-__mmap_new_vma.patch
mm-vma-introduce-and-use-vma_set_pgoff.patch
mm-vma-correct-incorrect-vmah-inclusion.patch
mm-vma-use-guard-clauses-in-can_vma_merge_.patch
tools-testing-vma-default-vma-mm-flag-bits-to-64-bit.patch
tools-testing-vma-output-compared-expression-on-assert_.patch