Commit 05275594 authored by Fan Ni's avatar Fan Ni Committed by Andrew Morton
Browse files

mm/hugetlb: convert use of struct page to folio in __unmap_hugepage_range() 

In __unmap_hugepage_range(), the "page" pointer always points to the first
page of a huge page, which guarantees there is a folio associating with
it.  Convert the "page" pointer to use folio.

Link: https://lkml.kernel.org/r/20250505182345.506888-6-nifan.cxl@gmail.com


Signed-off-by: default avatarFan Ni <fan.ni@samsung.com>
Reviewed-by: default avatarOscar Salvador <osalvador@suse.de>
Acked-by: default avatarDavid Hildenbrand <david@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Cc: "Vishal Moola (Oracle)" <vishal.moola@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 7f4b6065

mm/hugetlb.c

+13 −11
Original line number Diff line number Diff line
@@ -5843,11 +5843,11 @@ void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma, 
			    struct folio *folio, zap_flags_t zap_flags)

{

	struct mm_struct *mm = vma->vm_mm;

	const bool folio_provided = !!folio;

	unsigned long address;

	pte_t *ptep;

	pte_t pte;

	spinlock_t *ptl;

	struct page *page;

	struct hstate *h = hstate_vma(vma);

	unsigned long sz = huge_page_size(h);

	bool adjust_reservation = false;
@@ -5911,14 +5911,13 @@ void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma, 
			continue;

		}



		page = pte_page(pte);

		/*

		 * If a folio is supplied, it is because a specific

		 * folio is being unmapped, not a range. Ensure the folio we

		 * are about to unmap is the actual folio of interest.

		 */

		if (folio) {

			if (page_folio(page) != folio) {

		if (folio_provided) {

			if (folio != page_folio(pte_page(pte))) {

				spin_unlock(ptl);

				continue;

			}
@@ -5928,12 +5927,14 @@ void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma, 
			 * looking like data was lost

			 */

			set_vma_resv_flags(vma, HPAGE_RESV_UNMAPPED);

		} else {

			folio = page_folio(pte_page(pte));

		}



		pte = huge_ptep_get_and_clear(mm, address, ptep, sz);

		tlb_remove_huge_tlb_entry(h, tlb, ptep, address);

		if (huge_pte_dirty(pte))

			set_page_dirty(page);

			folio_mark_dirty(folio);

		/* Leave a uffd-wp pte marker if needed */

		if (huge_pte_uffd_wp(pte) &&

		    !(zap_flags & ZAP_FLAG_DROP_MARKER))
@@ -5941,7 +5942,7 @@ void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma, 
					make_pte_marker(PTE_MARKER_UFFD_WP),

					sz);

		hugetlb_count_sub(pages_per_huge_page(h), mm);

		hugetlb_remove_rmap(page_folio(page));

		hugetlb_remove_rmap(folio);



		/*

		 * Restore the reservation for anonymous page, otherwise the
@@ -5950,8 +5951,8 @@ void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma, 
		 * reservation bit.

		 */

		if (!h->surplus_huge_pages && __vma_private_lock(vma) &&

		    folio_test_anon(page_folio(page))) {

			folio_set_hugetlb_restore_reserve(page_folio(page));

		    folio_test_anon(folio)) {

			folio_set_hugetlb_restore_reserve(folio);

			/* Reservation to be adjusted after the spin lock */

			adjust_reservation = true;

		}
@@ -5975,16 +5976,17 @@ void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma, 
				 * count will not be incremented by free_huge_folio.

				 * Act as if we consumed the reservation.

				 */

				folio_clear_hugetlb_restore_reserve(page_folio(page));

				folio_clear_hugetlb_restore_reserve(folio);

			else if (rc)

				vma_add_reservation(h, vma, address);

		}



		tlb_remove_page_size(tlb, page, huge_page_size(h));

		tlb_remove_page_size(tlb, folio_page(folio, 0),

				     folio_size(folio));

		/*

		 * If we were instructed to unmap a specific folio, we're done.

		 */

		if (folio)

		if (folio_provided)

			break;

	}

	tlb_end_vma(tlb, vma);