+ mmhugetlb-rename-anon_rmap-to-new_anon_folio-and-make-it-boolean.patch added to mm-new branch

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

The patch titled
     Subject: mm,hugetlb: rename anon_rmap to new_anon_folio and make it boolean
has been added to the -mm mm-new branch.  Its filename is
     mmhugetlb-rename-anon_rmap-to-new_anon_folio-and-make-it-boolean.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mmhugetlb-rename-anon_rmap-to-new_anon_folio-and-make-it-boolean.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
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------------------------------------------------------
From: Oscar Salvador <osalvador@suse.de>
Subject: mm,hugetlb: rename anon_rmap to new_anon_folio and make it boolean
Date: Mon, 30 Jun 2025 16:42:10 +0200

anon_rmap is used to determine whether the new allocated folio is
anonymous.  Rename it to something more meaningul like new_anon_folio and
make it boolean, as we use it like that.

While we are at it, drop 'new_pagecache_folio' as 'new_anon_folio' is
enough to check whether we need to restore the consumed reservation.

Link: https://lkml.kernel.org/r/20250627102904.107202-4-osalvador@suse.de
Link: https://lkml.kernel.org/r/20250630144212.156938-4-osalvador@suse.de
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Cc: David Hildenbrand <david@redhat.com>
Cc: Gavin Guo <gavinguo@igalia.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/hugetlb.c |   19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

--- a/mm/hugetlb.c~mmhugetlb-rename-anon_rmap-to-new_anon_folio-and-make-it-boolean
+++ a/mm/hugetlb.c
@@ -6425,17 +6425,16 @@ static bool hugetlb_pte_stable(struct hs
 static vm_fault_t hugetlb_no_page(struct address_space *mapping,
 			struct vm_fault *vmf)
 {
+	u32 hash = hugetlb_fault_mutex_hash(mapping, vmf->pgoff);
+	bool new_folio, new_anon_folio = false;
 	struct vm_area_struct *vma = vmf->vma;
 	struct mm_struct *mm = vma->vm_mm;
 	struct hstate *h = hstate_vma(vma);
 	vm_fault_t ret = VM_FAULT_SIGBUS;
-	int anon_rmap = 0;
-	unsigned long size;
+	bool folio_locked = true;
 	struct folio *folio;
+	unsigned long size;
 	pte_t new_pte;
-	bool new_folio, new_pagecache_folio = false;
-	u32 hash = hugetlb_fault_mutex_hash(mapping, vmf->pgoff);
-	bool folio_locked = true;
 
 	/*
 	 * Currently, we are forced to kill the process in the event the
@@ -6534,10 +6533,9 @@ static vm_fault_t hugetlb_no_page(struct
 				ret = VM_FAULT_SIGBUS;
 				goto out;
 			}
-			new_pagecache_folio = true;
 		} else {
+			new_anon_folio = true;
 			folio_lock(folio);
-			anon_rmap = 1;
 		}
 	} else {
 		/*
@@ -6586,7 +6584,7 @@ static vm_fault_t hugetlb_no_page(struct
 	if (!pte_same(huge_ptep_get(mm, vmf->address, vmf->pte), vmf->orig_pte))
 		goto backout;
 
-	if (anon_rmap)
+	if (new_anon_folio)
 		hugetlb_add_new_anon_rmap(folio, vma, vmf->address);
 	else
 		hugetlb_add_file_rmap(folio);
@@ -6605,7 +6603,7 @@ static vm_fault_t hugetlb_no_page(struct
 		 * No need to keep file folios locked. See comment in
 		 * hugetlb_fault().
 		 */
-		if (!anon_rmap) {
+		if (!new_anon_folio) {
 			folio_locked = false;
 			folio_unlock(folio);
 		}
@@ -6641,7 +6639,8 @@ out:
 backout:
 	spin_unlock(vmf->ptl);
 backout_unlocked:
-	if (new_folio && !new_pagecache_folio)
+	/* We only need to restore reservations for private mappings */
+	if (new_anon_folio)
 		restore_reserve_on_error(h, vma, vmf->address, folio);
 
 	folio_unlock(folio);
_

Patches currently in -mm which might be from osalvador@suse.de are

mmslub-do-not-special-case-n_normal-nodes-for-slab_nodes.patch
mmmemory_hotplug-remove-status_change_nid_normal-and-update-documentation.patch
mmmemory_hotplug-implement-numa-node-notifier.patch
mmslub-use-node-notifier-instead-of-memory-notifier.patch
mmmemory-tiers-use-node-notifier-instead-of-memory-notifier.patch
driverscxl-use-node-notifier-instead-of-memory-notifier.patch
drivershmat-use-node-notifier-instead-of-memory-notifier.patch
kernelcpuset-use-node-notifier-instead-of-memory-notifier.patch
mmmempolicy-use-node-notifier-instead-of-memory-notifier.patch
mmpage_ext-derive-the-node-from-the-pfn.patch
mmmemory_hotplug-drop-status_change_nid-parameter-from-memory_notify.patch
mmhugetlb-change-mechanism-to-detect-a-cow-on-private-mapping.patch
mmhugetlb-sort-out-folio-locking-in-the-faulting-path.patch
mmhugetlb-rename-anon_rmap-to-new_anon_folio-and-make-it-boolean.patch
mmhugetlb-drop-obsolete-comment-about-non-present-pte-and-second-faults.patch
mmhugetlb-drop-unlikelys-from-hugetlb_fault.patch