Commit 405c4ef7 authored by David Hildenbrand's avatar David Hildenbrand Committed by Andrew Morton
Browse files

mm/rmap: pass dst_vma to folio_dup_file_rmap_pte() and friends 

We'll need access to the destination MM when modifying the large mapcount
of a non-hugetlb large folios next.  So pass in the destination VMA.

Link: https://lkml.kernel.org/r/20250303163014.1128035-8-david@redhat.com


Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
Cc: Andy Lutomirks^H^Hski <luto@kernel.org>
Cc: Borislav Betkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Lance Yang <ioworker0@gmail.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Matthew Wilcow (Oracle) <willy@infradead.org>
Cc: Michal Koutn <mkoutny@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: tejun heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zefan Li <lizefan.x@bytedance.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 845d2be6

include/linux/rmap.h

+25 −17
Original line number Diff line number Diff line
@@ -335,7 +335,8 @@ static inline void hugetlb_remove_rmap(struct folio *folio) 
}



static __always_inline void __folio_dup_file_rmap(struct folio *folio,

		struct page *page, int nr_pages, enum rmap_level level)

		struct page *page, int nr_pages, struct vm_area_struct *dst_vma,

		enum rmap_level level)

{

	const int orig_nr_pages = nr_pages;
@@ -366,45 +367,47 @@ static __always_inline void __folio_dup_file_rmap(struct folio *folio, 
 * @folio:	The folio to duplicate the mappings of

 * @page:	The first page to duplicate the mappings of

 * @nr_pages:	The number of pages of which the mapping will be duplicated

 * @dst_vma:	The destination vm area

 *

 * The page range of the folio is defined by [page, page + nr_pages)

 *

 * The caller needs to hold the page table lock.

 */

static inline void folio_dup_file_rmap_ptes(struct folio *folio,

		struct page *page, int nr_pages)

		struct page *page, int nr_pages, struct vm_area_struct *dst_vma)

{

	__folio_dup_file_rmap(folio, page, nr_pages, RMAP_LEVEL_PTE);

	__folio_dup_file_rmap(folio, page, nr_pages, dst_vma, RMAP_LEVEL_PTE);

}



static __always_inline void folio_dup_file_rmap_pte(struct folio *folio,

		struct page *page)

		struct page *page, struct vm_area_struct *dst_vma)

{

	__folio_dup_file_rmap(folio, page, 1, RMAP_LEVEL_PTE);

	__folio_dup_file_rmap(folio, page, 1, dst_vma, RMAP_LEVEL_PTE);

}



/**

 * folio_dup_file_rmap_pmd - duplicate a PMD mapping of a page range of a folio

 * @folio:	The folio to duplicate the mapping of

 * @page:	The first page to duplicate the mapping of

 * @dst_vma:	The destination vm area

 *

 * The page range of the folio is defined by [page, page + HPAGE_PMD_NR)

 *

 * The caller needs to hold the page table lock.

 */

static inline void folio_dup_file_rmap_pmd(struct folio *folio,

		struct page *page)

		struct page *page, struct vm_area_struct *dst_vma)

{

#ifdef CONFIG_TRANSPARENT_HUGEPAGE

	__folio_dup_file_rmap(folio, page, HPAGE_PMD_NR, RMAP_LEVEL_PTE);

	__folio_dup_file_rmap(folio, page, HPAGE_PMD_NR, dst_vma, RMAP_LEVEL_PTE);

#else

	WARN_ON_ONCE(true);

#endif

}



static __always_inline int __folio_try_dup_anon_rmap(struct folio *folio,

		struct page *page, int nr_pages, struct vm_area_struct *src_vma,

		enum rmap_level level)

		struct page *page, int nr_pages, struct vm_area_struct *dst_vma,

		struct vm_area_struct *src_vma, enum rmap_level level)

{

	const int orig_nr_pages = nr_pages;

	bool maybe_pinned;
@@ -470,6 +473,7 @@ static __always_inline int __folio_try_dup_anon_rmap(struct folio *folio, 
 * @folio:	The folio to duplicate the mappings of

 * @page:	The first page to duplicate the mappings of

 * @nr_pages:	The number of pages of which the mapping will be duplicated

 * @dst_vma:	The destination vm area

 * @src_vma:	The vm area from which the mappings are duplicated

 *

 * The page range of the folio is defined by [page, page + nr_pages)
@@ -488,16 +492,18 @@ static __always_inline int __folio_try_dup_anon_rmap(struct folio *folio, 
 * Returns 0 if duplicating the mappings succeeded. Returns -EBUSY otherwise.

 */

static inline int folio_try_dup_anon_rmap_ptes(struct folio *folio,

		struct page *page, int nr_pages, struct vm_area_struct *src_vma)

		struct page *page, int nr_pages, struct vm_area_struct *dst_vma,

		struct vm_area_struct *src_vma)

{

	return __folio_try_dup_anon_rmap(folio, page, nr_pages, src_vma,

					 RMAP_LEVEL_PTE);

	return __folio_try_dup_anon_rmap(folio, page, nr_pages, dst_vma,

					 src_vma, RMAP_LEVEL_PTE);

}



static __always_inline int folio_try_dup_anon_rmap_pte(struct folio *folio,

		struct page *page, struct vm_area_struct *src_vma)

		struct page *page, struct vm_area_struct *dst_vma,

		struct vm_area_struct *src_vma)

{

	return __folio_try_dup_anon_rmap(folio, page, 1, src_vma,

	return __folio_try_dup_anon_rmap(folio, page, 1, dst_vma, src_vma,

					 RMAP_LEVEL_PTE);

}
@@ -506,6 +512,7 @@ static __always_inline int folio_try_dup_anon_rmap_pte(struct folio *folio, 
 *				 of a folio

 * @folio:	The folio to duplicate the mapping of

 * @page:	The first page to duplicate the mapping of

 * @dst_vma:	The destination vm area

 * @src_vma:	The vm area from which the mapping is duplicated

 *

 * The page range of the folio is defined by [page, page + HPAGE_PMD_NR)
@@ -524,11 +531,12 @@ static __always_inline int folio_try_dup_anon_rmap_pte(struct folio *folio, 
 * Returns 0 if duplicating the mapping succeeded. Returns -EBUSY otherwise.

 */

static inline int folio_try_dup_anon_rmap_pmd(struct folio *folio,

		struct page *page, struct vm_area_struct *src_vma)

		struct page *page, struct vm_area_struct *dst_vma,

		struct vm_area_struct *src_vma)

{

#ifdef CONFIG_TRANSPARENT_HUGEPAGE

	return __folio_try_dup_anon_rmap(folio, page, HPAGE_PMD_NR, src_vma,

					 RMAP_LEVEL_PMD);

	return __folio_try_dup_anon_rmap(folio, page, HPAGE_PMD_NR, dst_vma,

					 src_vma, RMAP_LEVEL_PMD);

#else

	WARN_ON_ONCE(true);

	return -EBUSY;

mm/huge_memory.c

+1 −1
Original line number Diff line number Diff line
@@ -1782,7 +1782,7 @@ int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm, 
	src_folio = page_folio(src_page);



	folio_get(src_folio);

	if (unlikely(folio_try_dup_anon_rmap_pmd(src_folio, src_page, src_vma))) {

	if (unlikely(folio_try_dup_anon_rmap_pmd(src_folio, src_page, dst_vma, src_vma))) {

		/* Page maybe pinned: split and retry the fault on PTEs. */

		folio_put(src_folio);

		pte_free(dst_mm, pgtable);

mm/memory.c

+5 −5
Original line number Diff line number Diff line
@@ -864,7 +864,7 @@ copy_nonpresent_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm, 
		folio_get(folio);

		rss[mm_counter(folio)]++;

		/* Cannot fail as these pages cannot get pinned. */

		folio_try_dup_anon_rmap_pte(folio, page, src_vma);

		folio_try_dup_anon_rmap_pte(folio, page, dst_vma, src_vma);



		/*

		 * We do not preserve soft-dirty information, because so
@@ -1018,14 +1018,14 @@ copy_present_ptes(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma 
		folio_ref_add(folio, nr);

		if (folio_test_anon(folio)) {

			if (unlikely(folio_try_dup_anon_rmap_ptes(folio, page,

								  nr, src_vma))) {

								  nr, dst_vma, src_vma))) {

				folio_ref_sub(folio, nr);

				return -EAGAIN;

			}

			rss[MM_ANONPAGES] += nr;

			VM_WARN_ON_FOLIO(PageAnonExclusive(page), folio);

		} else {

			folio_dup_file_rmap_ptes(folio, page, nr);

			folio_dup_file_rmap_ptes(folio, page, nr, dst_vma);

			rss[mm_counter_file(folio)] += nr;

		}

		if (any_writable)
@@ -1043,7 +1043,7 @@ copy_present_ptes(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma 
		 * guarantee the pinned page won't be randomly replaced in the

		 * future.

		 */

		if (unlikely(folio_try_dup_anon_rmap_pte(folio, page, src_vma))) {

		if (unlikely(folio_try_dup_anon_rmap_pte(folio, page, dst_vma, src_vma))) {

			/* Page may be pinned, we have to copy. */

			folio_put(folio);

			err = copy_present_page(dst_vma, src_vma, dst_pte, src_pte,
@@ -1053,7 +1053,7 @@ copy_present_ptes(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma 
		rss[MM_ANONPAGES]++;

		VM_WARN_ON_FOLIO(PageAnonExclusive(page), folio);

	} else {

		folio_dup_file_rmap_pte(folio, page);

		folio_dup_file_rmap_pte(folio, page, dst_vma);

		rss[mm_counter_file(folio)]++;

	}