Commit b890ec2a authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle)
Browse files

hugetlb: Convert to migrate_folio 



This involves converting migrate_huge_page_move_mapping().  We also need a
folio variant of hugetlb_set_page_subpool(), but that's for a later patch.

Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: default avatarMuchun Song <songmuchun@bytedance.com>
Reviewed-by: default avatarMike Kravetz <mike.kravetz@oracle.com>
parent 3648951c

fs/hugetlbfs/inode.c

+14 −9
Original line number Diff line number Diff line
@@ -954,28 +954,33 @@ static int hugetlbfs_symlink(struct user_namespace *mnt_userns, 
	return error;

}



static int hugetlbfs_migrate_page(struct address_space *mapping,

				struct page *newpage, struct page *page,

#ifdef CONFIG_MIGRATION

static int hugetlbfs_migrate_folio(struct address_space *mapping,

				struct folio *dst, struct folio *src,

				enum migrate_mode mode)

{

	int rc;



	rc = migrate_huge_page_move_mapping(mapping, newpage, page);

	rc = migrate_huge_page_move_mapping(mapping, dst, src);

	if (rc != MIGRATEPAGE_SUCCESS)

		return rc;



	if (hugetlb_page_subpool(page)) {

		hugetlb_set_page_subpool(newpage, hugetlb_page_subpool(page));

		hugetlb_set_page_subpool(page, NULL);

	if (hugetlb_page_subpool(&src->page)) {

		hugetlb_set_page_subpool(&dst->page,

					hugetlb_page_subpool(&src->page));

		hugetlb_set_page_subpool(&src->page, NULL);

	}



	if (mode != MIGRATE_SYNC_NO_COPY)

		migrate_page_copy(newpage, page);

		folio_migrate_copy(dst, src);

	else

		migrate_page_states(newpage, page);

		folio_migrate_flags(dst, src);



	return MIGRATEPAGE_SUCCESS;

}

#else

#define hugetlbfs_migrate_folio NULL

#endif



static int hugetlbfs_error_remove_page(struct address_space *mapping,

				struct page *page)
@@ -1142,7 +1147,7 @@ static const struct address_space_operations hugetlbfs_aops = { 
	.write_begin	= hugetlbfs_write_begin,

	.write_end	= hugetlbfs_write_end,

	.dirty_folio	= noop_dirty_folio,

	.migratepage    = hugetlbfs_migrate_page,

	.migrate_folio  = hugetlbfs_migrate_folio,

	.error_remove_page	= hugetlbfs_error_remove_page,

};

include/linux/migrate.h

+3 −3
Original line number Diff line number Diff line
@@ -72,8 +72,8 @@ extern int isolate_movable_page(struct page *page, isolate_mode_t mode); 


extern void migrate_page_states(struct page *newpage, struct page *page);

extern void migrate_page_copy(struct page *newpage, struct page *page);

extern int migrate_huge_page_move_mapping(struct address_space *mapping,

				  struct page *newpage, struct page *page);

int migrate_huge_page_move_mapping(struct address_space *mapping,

		struct folio *dst, struct folio *src);

extern int migrate_page_move_mapping(struct address_space *mapping,

		struct page *newpage, struct page *page, int extra_count);

void migration_entry_wait_on_locked(swp_entry_t entry, pte_t *ptep,
@@ -104,7 +104,7 @@ static inline void migrate_page_copy(struct page *newpage, 
				     struct page *page) {}



static inline int migrate_huge_page_move_mapping(struct address_space *mapping,

				  struct page *newpage, struct page *page)

				  struct folio *dst, struct folio *src)

{

	return -ENOSYS;

}

mm/migrate.c

+9 −9
Original line number Diff line number Diff line
@@ -474,26 +474,26 @@ EXPORT_SYMBOL(folio_migrate_mapping); 
 * of folio_migrate_mapping().

 */

int migrate_huge_page_move_mapping(struct address_space *mapping,

				   struct page *newpage, struct page *page)

				   struct folio *dst, struct folio *src)

{

	XA_STATE(xas, &mapping->i_pages, page_index(page));

	XA_STATE(xas, &mapping->i_pages, folio_index(src));

	int expected_count;



	xas_lock_irq(&xas);

	expected_count = 2 + page_has_private(page);

	if (!page_ref_freeze(page, expected_count)) {

	expected_count = 2 + folio_has_private(src);

	if (!folio_ref_freeze(src, expected_count)) {

		xas_unlock_irq(&xas);

		return -EAGAIN;

	}



	newpage->index = page->index;

	newpage->mapping = page->mapping;

	dst->index = src->index;

	dst->mapping = src->mapping;



	get_page(newpage);

	folio_get(dst);



	xas_store(&xas, newpage);

	xas_store(&xas, dst);



	page_ref_unfreeze(page, expected_count - 1);

	folio_ref_unfreeze(src, expected_count - 1);



	xas_unlock_irq(&xas);