[merged mm-stable] mm-vma-introduce-and-use-vmg_pages-vmg__pgoff.patch removed from -mm tree

[merged mm-stable] mm-vma-introduce-and-use-vmg_pages-vmg__pgoff.patch removed from -mm tree

[Andrew Morton]

The quilt patch titled
     Subject: mm/vma: introduce and use vmg_pages(), vmg_[start, end]_pgoff()
has been removed from the -mm tree.  Its filename was
     mm-vma-introduce-and-use-vmg_pages-vmg__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 <ljs@kernel.org>
Subject: mm/vma: introduce and use vmg_pages(), vmg_[start, end]_pgoff()
Date: Fri, 10 Jul 2026 21:16:54 +0100

In the VMA logic we often need to determine the number of pages in the
specified merge range, as well as the start and end page offsets of that
range.

Introduce and use helpers for these purposes.

No functional change intended.

Link: https://lore.kernel.org/20260710-b4-pre-scalable-cow-v2-13-2a5aa403d977@kernel.org
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Reviewed-by: Gregory Price <gourry@gourry.net>
Reviewed-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Ackerley Tng <ackerleytng@google.com>
Cc: David Hildenbrand (Arm) <david@kernel.org>
Cc: Kai Huang <kai.huang@intel.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: SJ Park <sj@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Liam R. Howlett (Oracle) <liam@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/vma.c |   11 ++++-------
 mm/vma.h |   17 +++++++++++++++++
 2 files changed, 21 insertions(+), 7 deletions(-)

--- a/mm/vma.c~mm-vma-introduce-and-use-vmg_pages-vmg__pgoff
+++ a/mm/vma.c
@@ -197,11 +197,9 @@ static void init_multi_vma_prep(struct v
  */
 static bool can_vma_merge_before(struct vma_merge_struct *vmg)
 {
-	pgoff_t pglen = PHYS_PFN(vmg->end - vmg->start);
-
 	if (is_mergeable_vma(vmg, /* merge_next = */ true) &&
 	    is_mergeable_anon_vma(vmg, /* merge_next = */ true)) {
-		if (vmg->next->vm_pgoff == vmg->pgoff + pglen)
+		if (vmg_end_pgoff(vmg) == vma_start_pgoff(vmg->next))
 			return true;
 	}
 
@@ -221,7 +219,7 @@ static bool can_vma_merge_after(struct v
 {
 	if (is_mergeable_vma(vmg, /* merge_next = */ false) &&
 	    is_mergeable_anon_vma(vmg, /* merge_next = */ false)) {
-		if (vmg->prev->vm_pgoff + vma_pages(vmg->prev) == vmg->pgoff)
+		if (vma_end_pgoff(vmg->prev) == vmg_start_pgoff(vmg))
 			return true;
 	}
 	return false;
@@ -759,7 +757,7 @@ static int commit_merge(struct vma_merge
 	 */
 	vma_adjust_trans_huge(vma, vmg->start, vmg->end,
 			      vmg->__adjust_middle_start ? vmg->middle : NULL);
-	vma_set_range(vma, vmg->start, vmg->end, vmg->pgoff);
+	vma_set_range(vma, vmg->start, vmg->end, vmg_start_pgoff(vmg));
 	vmg_adjust_set_range(vmg);
 	vma_iter_store_overwrite(vmg->vmi, vmg->target);
 
@@ -962,8 +960,7 @@ static __must_check struct vm_area_struc
 		 *    middle     next
 		 * shrink/delete extend
 		 */
-
-		pgoff_t pglen = PHYS_PFN(vmg->end - vmg->start);
+		const pgoff_t pglen = vmg_pages(vmg);
 
 		VM_WARN_ON_VMG(!merge_right, vmg);
 		/* If we are offset into a VMA, then prev must be middle. */
--- a/mm/vma.h~mm-vma-introduce-and-use-vmg_pages-vmg__pgoff
+++ a/mm/vma.h
@@ -230,6 +230,23 @@ static inline bool vmg_nomem(struct vma_
 	return vmg->state == VMA_MERGE_ERROR_NOMEM;
 }
 
+static inline pgoff_t vmg_start_pgoff(const struct vma_merge_struct *vmg)
+{
+	return vmg->pgoff;
+}
+
+static inline pgoff_t vmg_pages(const struct vma_merge_struct *vmg)
+{
+	const unsigned long size = vmg->end - vmg->start;
+
+	return size >> PAGE_SHIFT;
+}
+
+static inline pgoff_t vmg_end_pgoff(const struct vma_merge_struct *vmg)
+{
+	return vmg_start_pgoff(vmg) + vmg_pages(vmg);
+}
+
 /* Assumes addr >= vma->vm_start. */
 static inline pgoff_t vma_pgoff_offset(struct vm_area_struct *vma,
 				       unsigned long addr)
_

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