+ mm-sparse-vmemmap-drop-unused-section_nr_vmemmap_pages-arguments.patch added to mm-unstable branch

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

The patch titled
     Subject: mm/sparse-vmemmap: drop unused section_nr_vmemmap_pages() arguments
has been added to the -mm mm-unstable branch.  Its filename is
     mm-sparse-vmemmap-drop-unused-section_nr_vmemmap_pages-arguments.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-sparse-vmemmap-drop-unused-section_nr_vmemmap_pages-arguments.patch

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

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------------------------------------------------------
From: Muchun Song <muchun.song@linux.dev>
Subject: mm/sparse-vmemmap: drop unused section_nr_vmemmap_pages() arguments
Date: Sun, 27 Sep 2026 10:54:40 +0800

section_nr_vmemmap_pages() no longer uses the altmap or pgmap
arguments, so drop them from the helper and its callers.

Link: https://lore.kernel.org/20260927025441.741633-12-songmuchun@bytedance.com
Signed-off-by: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Qi Zheng <qi.zheng@linux.dev>
Cc: David Hildenbrand <david@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Christophe Leroy <chleroy@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Lance Yang <lance.yang@linux.dev>
---

 mm/sparse-vmemmap.c |   10 ++++------
 mm/sparse.c         |    3 +--
 mm/sparse.h         |    6 ++----
 3 files changed, 7 insertions(+), 12 deletions(-)

--- a/mm/sparse.c~mm-sparse-vmemmap-drop-unused-section_nr_vmemmap_pages-arguments
+++ a/mm/sparse.c
@@ -250,8 +250,7 @@ static void __init sparse_init_nid(int n
 						nid, NULL, NULL);
 		if (!map)
 			panic("Failed to allocate memmap for section %lu\n", pnum);
-		memmap_boot_pages_add(section_nr_vmemmap_pages(pfn, PAGES_PER_SECTION,
-							       NULL, NULL));
+		memmap_boot_pages_add(section_nr_vmemmap_pages(pfn, PAGES_PER_SECTION));
 		sparse_init_one_section(__nr_to_section(pnum), pnum, map, usage,
 					SECTION_IS_EARLY);
 		usage = (void *)usage + mem_section_usage_size();
--- a/mm/sparse.h~mm-sparse-vmemmap-drop-unused-section_nr_vmemmap_pages-arguments
+++ a/mm/sparse.h
@@ -70,12 +70,10 @@ static inline void sparse_sections_init(
  */
 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 void sparse_init_subsection_map(void);
-int section_nr_vmemmap_pages(unsigned long pfn, unsigned long nr_pages,
-		struct vmem_altmap *altmap, struct dev_pagemap *pgmap);
+int section_nr_vmemmap_pages(unsigned long pfn, unsigned long nr_pages);
 #else
 static inline void sparse_init_subsection_map(void) {}
-static inline int section_nr_vmemmap_pages(unsigned long pfn, unsigned long nr_pages,
-		struct vmem_altmap *altmap, struct dev_pagemap *pgmap)
+static inline int section_nr_vmemmap_pages(unsigned long pfn, unsigned long nr_pages)
 {
 	return DIV_ROUND_UP(nr_pages * sizeof(struct page), PAGE_SIZE);
 }
--- a/mm/sparse-vmemmap.c~mm-sparse-vmemmap-drop-unused-section_nr_vmemmap_pages-arguments
+++ a/mm/sparse-vmemmap.c
@@ -131,8 +131,7 @@ void __meminit vmemmap_verify(pte_t *pte
 			start, end - 1);
 }
 
-int __meminit section_nr_vmemmap_pages(unsigned long pfn, unsigned long nr_pages,
-		struct vmem_altmap *altmap, struct dev_pagemap *pgmap)
+int __meminit section_nr_vmemmap_pages(unsigned long pfn, unsigned long nr_pages)
 {
 	const struct mem_section *ms = __pfn_to_section(pfn);
 	const int order = section_compound_order(ms);
@@ -666,7 +665,7 @@ static struct page * __meminit populate_
 	struct page *page = __populate_section_memmap(pfn, nr_pages, nid, altmap,
 						      pgmap);
 
-	memmap_pages_add(section_nr_vmemmap_pages(pfn, nr_pages, altmap, pgmap));
+	memmap_pages_add(section_nr_vmemmap_pages(pfn, nr_pages));
 
 	return page;
 }
@@ -677,7 +676,7 @@ static void depopulate_section_memmap(un
 	unsigned long start = (unsigned long) pfn_to_page(pfn);
 	unsigned long end = start + nr_pages * sizeof(struct page);
 
-	memmap_pages_add(-section_nr_vmemmap_pages(pfn, nr_pages, altmap, pgmap));
+	memmap_pages_add(-section_nr_vmemmap_pages(pfn, nr_pages));
 	vmemmap_free(start, end, altmap);
 }
 
@@ -687,8 +686,7 @@ static void free_map_bootmem(struct page
 	unsigned long end = (unsigned long)(memmap + PAGES_PER_SECTION);
 	unsigned long pfn = page_to_pfn(memmap);
 
-	memmap_boot_pages_add(-section_nr_vmemmap_pages(pfn, PAGES_PER_SECTION,
-							NULL, NULL));
+	memmap_boot_pages_add(-section_nr_vmemmap_pages(pfn, PAGES_PER_SECTION));
 	vmemmap_free(start, end, NULL);
 }
 
_

Patches currently in -mm which might be from muchun.song@linux.dev are

mm-sparse-vmemmap-factor-out-shared-vmemmap-tail-page-allocation.patch
mm-sparse-vmemmap-allocate-shared-tail-page-array-dynamically.patch
mm-sparse-vmemmap-introduce-config_vmemmap_optimization.patch
mm-sparse-vmemmap-open-code-init_compound_tail.patch
mm-sparse-vmemmap-prepare-dax-vmemmap-population-for-compound-page-orders.patch
mm-sparse-vmemmap-set-compound-page-order-for-device-dax.patch
mm-sparse-vmemmap-switch-device-dax-to-shared-tail-vmemmap-pages.patch
mm-sparse-vmemmap-move-vmemmap-optimization-helpers-to-a-public-header.patch
powerpc-mm-switch-device-dax-to-shared-tail-vmemmap-pages.patch
mm-sparse-vmemmap-drop-the-extra-tail-page-from-device-dax-reservation.patch
mm-sparse-vmemmap-drop-unused-section_nr_vmemmap_pages-arguments.patch
documentation-mm-update-dax-vmemmap-deduplication-docs.patch