[merged mm-stable] mm-vma-add-and-use-vma__pgoff.patch removed from -mm tree

The quilt patch titled
     Subject: mm/vma: add and use vma_[add/sub]_pgoff()
has been removed from the -mm tree.  Its filename was
     mm-vma-add-and-use-vma__pgoff.patch

This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

------------------------------------------------------
From: Lorenzo Stoakes <[email protected]>
Subject: mm/vma: add and use vma_[add/sub]_pgoff()
Date: Fri, 10 Jul 2026 21:17:04 +0100

Add helpers for adding or subtracting to a VMA's page offset, exposed
internally for VMA users within mm in mm/vma.h.

This is to lay the foundations for tracking anonymous page offset for
MAP_PRIVATE file-backed mappings, where adding and subtracting from this
value must be reflected in both the file and anonymous offsets.

These are used on VMA split and downward stack expansion.

No functional change intended.

[[email protected]: use linear_page_delta() in __split_vma(), per Vlastimal & Lorenzo]
Link: https://lore.kernel.org/[email protected]
Signed-off-by: Lorenzo Stoakes <[email protected]>
Reviewed-by: Pedro Falcato <[email protected]>
Reviewed-by: Gregory Price <[email protected]>
Reviewed-by: Vlastimil Babka (SUSE) <[email protected]>
Cc: Ackerley Tng <[email protected]>
Cc: David Hildenbrand (Arm) <[email protected]>
Cc: Kai Huang <[email protected]>
Cc: Marek Szyprowski <[email protected]>
Cc: SJ Park <[email protected]>
Cc: Thomas Zimmermann <[email protected]>
Cc: Liam R. Howlett (Oracle) <[email protected]>
Cc: Zi Yan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
---

 mm/nommu.c |    6 ++++--
 mm/vma.c   |    6 +++---
 mm/vma.h   |   12 ++++++++++++
 3 files changed, 19 insertions(+), 5 deletions(-)

--- a/mm/nommu.c~mm-vma-add-and-use-vma__pgoff
+++ a/mm/nommu.c
@@ -41,6 +41,7 @@
 #include <asm/tlbflush.h>
 #include <asm/mmu_context.h>
 #include "internal.h"
+#include "vma.h"
 
 unsigned long highest_memmap_pfn;
 int heap_stack_gap = 0;
@@ -1361,7 +1362,8 @@ static int split_vma(struct vma_iterator
 		region->vm_top = region->vm_end = new->vm_end = addr;
 	} else {
 		region->vm_start = new->vm_start = addr;
-		region->vm_pgoff = new->vm_pgoff += npages;
+		vma_add_pgoff(new, npages);
+		region->vm_pgoff = vma_start_pgoff(new);
 	}
 
 	vma_iter_config(vmi, new->vm_start, new->vm_end);
@@ -1378,7 +1380,7 @@ static int split_vma(struct vma_iterator
 	delete_nommu_region(vma->vm_region);
 	if (new_below) {
 		vma->vm_region->vm_start = vma->vm_start = addr;
-		vma->vm_pgoff += npages;
+		vma_add_pgoff(vma, npages);
 		vma->vm_region->vm_pgoff = vma_start_pgoff(vma);
 	} else {
 		vma->vm_region->vm_end = vma->vm_end = addr;
--- a/mm/vma.c~mm-vma-add-and-use-vma__pgoff
+++ a/mm/vma.c
@@ -517,7 +517,7 @@ __split_vma(struct vma_iterator *vmi, st
 		new->vm_end = addr;
 	} else {
 		new->vm_start = addr;
-		new->vm_pgoff += linear_page_delta(vma, addr);
+		vma_add_pgoff(new, linear_page_delta(vma, addr));
 	}
 
 	err = -ENOMEM;
@@ -556,7 +556,7 @@ __split_vma(struct vma_iterator *vmi, st
 
 	if (new_below) {
 		vma->vm_start = addr;
-		vma->vm_pgoff += (addr - new->vm_start) >> PAGE_SHIFT;
+		vma_add_pgoff(vma, linear_page_delta(new, addr));
 	} else {
 		vma->vm_end = addr;
 	}
@@ -3305,7 +3305,7 @@ int expand_downwards(struct vm_area_stru
 				vm_stat_account(mm, vma->vm_flags, grow);
 				anon_rmap_tree_pre_update_vma(vma);
 				vma->vm_start = address;
-				vma->vm_pgoff -= grow;
+				vma_sub_pgoff(vma, grow);
 				/* Overwrite old entry in mtree. */
 				vma_iter_store_overwrite(&vmi, vma);
 				anon_rmap_tree_post_update_vma(vma);
--- a/mm/vma.h~mm-vma-add-and-use-vma__pgoff
+++ a/mm/vma.h
@@ -247,6 +247,18 @@ static inline pgoff_t vmg_end_pgoff(cons
 	return vmg_start_pgoff(vmg) + vmg_pages(vmg);
 }
 
+static inline void vma_add_pgoff(struct vm_area_struct *vma, pgoff_t delta)
+{
+	vma_assert_can_modify(vma);
+	vma->vm_pgoff += delta;
+}
+
+static inline void vma_sub_pgoff(struct vm_area_struct *vma, pgoff_t delta)
+{
+	vma_assert_can_modify(vma);
+	vma->vm_pgoff -= delta;
+}
+
 #define VMG_STATE(name, mm_, vmi_, start_, end_, vma_flags_, pgoff_)	\
 	struct vma_merge_struct name = {				\
 		.mm = mm_,						\
_

Patches currently in -mm which might be from [email protected] are

mm-vmalloc-acquire-init_mm-lock-on-huge-vmap-to-avoid-ptdump-uaf.patch
mm-ptdump-always-stabilise-against-page-table-freeing-using-init_mm.patch
arm64-remove-redundant-concurrent-ptdump-uaf-mitigation.patch
mm-huge_memory-fix-huge_zero_pfn-race.patch
mm-huge_memory-separate-out-config_persistent_huge_zero_folio-logic.patch
x86-mm-pat-acquire-init_mm-write-lock-on-collapse-to-avoid-uaf.patch
x86-mm-pat-acquire-init_mm-read-lock-on-attribute-change-to-avoid-uaf.patch
x86-mm-pat-allocate-split-page-tables-as-kernel-page-tables.patch
mm-introduce-vma_flags_can_grow-and-vma_can_grow.patch
mm-vma-update-do_mmap-to-use-vma_flags_t.patch
mm-convert-__get_unmapped_area-to-use-vma_flags_t.patch
mm-update-generic_get_unmapped_area-to-use-vma_flags_t.patch
mm-prefer-mm-def_vma_flags-in-mm-logic.patch
mm-vma-convert-vm_pgprot_modify-to-use-vma_flags_t-and-rename.patch
mm-vma-rename-vma_get_page_prot-to-vma_flags_to_page_prot.patch
mm-introduce-vma_get_page_prot-and-use-it.patch
mm-vma-update-create_init_stack_vma-to-use-vma_flags_t.patch
mm-vma-convert-miscellaneous-uses-of-vma-flags-in-core-mm.patch
mm-mlock-convert-mlock-code-to-use-vma_flags_t.patch
mm-mprotect-convert-mprotect-code-to-use-vma_flags_t.patch
mm-mremap-convert-mremap-code-to-use-vma_flags_t.patch
mm-mseal-remove-superfluous-comments-fix-confusion-around-mm.patch
mm-mseal-limit-scope-of-mseal-address-zero-to-address-zero.patch
mm-mseal-remove-further-superfluous-comments-do_mseal.patch
mm-vma-introduce-vma-virtual-page-offset-field-and-add-helpers.patch
mm-introduce-linear_virt_page_index.patch
mm-abstract-vma_address-and-introduce-vma_anon_address.patch
mm-update-print_bad_page_map-to-show-virtual-page-index.patch
mm-introduce-and-use-vma_filebacked_address.patch
mm-propagate-vma-virtual-page-offset-on-map-remap-split-merge.patch
mm-rmap-track-whether-the-page-vma-mapped-walk-is-anonymous.patch
mm-introduce-and-use-linear_folio_page_index.patch
mm-rmap-use-virt-pgoff-for-map_private-file-backed-anon-folios.patch
tools-testing-vma-expand-vma-merge-tests-to-assert-virt-pgoff.patch
tools-testing-selftests-mm-test-virtual-page-offset-merge-behaviour.patch
mm-vma-only-permit-map_private-dev-zero-to-be-mapped-anonymous.patch
mm-vma-make-map_private-mapped-dev-zero-mappings-truly-anonymous.patch
tools-testing-vma-add-test-to-assert-map_private-dev-zero-is-anon.patch
tools-testing-selftests-mm-add-map_private-dev-zero-merge-tests.patch
mm-add-some-missing-includes-to-mm-local-headers.patch