[PATCH v2 3/5] mm,hugetlb: Rename anon_rmap to new_anon_folio and make it boolean

Oscar Salvador
2025-06-20T12:30:33Z

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.

Signed-off-by: Oscar Salvador <osalvador@suse.de>
---
mm/hugetlb.c | 19 +++++++++----------
1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 1a5f713c1e4c..57bb8b2dce21 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -6427,17 +6427,16 @@ static bool hugetlb_pte_stable(struct hstate *h, struct mm_struct *mm, unsigned
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
@@ -6518,6 +6517,7 @@ static vm_fault_t hugetlb_no_page(struct address_space *mapping,
folio_zero_user(folio, vmf->real_address);
__folio_mark_uptodate(folio);
new_folio = true;
+ new_anon_folio = !(vma->vm_flags & VM_MAYSHARE);

if (vma->vm_flags & VM_MAYSHARE) {
int err = hugetlb_add_to_page_cache(folio, mapping,
@@ -6536,10 +6536,8 @@ static vm_fault_t hugetlb_no_page(struct address_space *mapping,
ret = VM_FAULT_SIGBUS;
goto out;
}
- new_pagecache_folio = true;
} else {
folio_lock(folio);
- anon_rmap = 1;
}
} else {
/*
@@ -6588,7 +6586,7 @@ static vm_fault_t hugetlb_no_page(struct address_space *mapping,
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);
@@ -6604,7 +6602,7 @@ static vm_fault_t hugetlb_no_page(struct address_space *mapping,
hugetlb_count_add(pages_per_huge_page(h), mm);
if ((vmf->flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) {
/* No need to lock file folios. See comment in hugetlb_fault() */
- if (!anon_rmap) {
+ if (!new_anon_folio) {
folio_locked = false;
folio_unlock(folio);
}
@@ -6640,7 +6638,8 @@ static vm_fault_t hugetlb_no_page(struct address_space *mapping,
backout:
spin_unlock(vmf->ptl);
backout_unlocked:
- if (new_folio && !new_pagecache_folio)
+ /* We only need to restore reservations for private mappings */
+ if (new_folio && new_anon_folio)
restore_reserve_on_error(h, vma, vmf->address, folio);

if (folio_locked)
--
2.50.0