From 715cbfd6c5c595bc8b7a6f9ad1fe9fec0122bb20 Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Fri, 7 May 2021 15:05:06 -0400 Subject: mm/migrate: Add folio_migrate_copy() This is the folio equivalent of migrate_page_copy(), which is retained as a wrapper for filesystems which are not yet converted to folios. Also convert copy_huge_page() to folio_copy(). Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Zi Yan Acked-by: Vlastimil Babka --- include/linux/migrate.h | 1 + include/linux/mm.h | 2 +- mm/folio-compat.c | 6 ++++++ mm/hugetlb.c | 2 +- mm/migrate.c | 14 +++++--------- mm/util.c | 21 +++++++++++++++++---- 6 files changed, 31 insertions(+), 15 deletions(-) diff --git a/include/linux/migrate.h b/include/linux/migrate.h index aa875b83f7ba..0d2aeb9b0f66 100644 --- a/include/linux/migrate.h +++ b/include/linux/migrate.h @@ -58,6 +58,7 @@ extern int migrate_huge_page_move_mapping(struct address_space *mapping, extern int migrate_page_move_mapping(struct address_space *mapping, struct page *newpage, struct page *page, int extra_count); void folio_migrate_flags(struct folio *newfolio, struct folio *folio); +void folio_migrate_copy(struct folio *newfolio, struct folio *folio); int folio_migrate_mapping(struct address_space *mapping, struct folio *newfolio, struct folio *folio, int extra_count); #else diff --git a/include/linux/mm.h b/include/linux/mm.h index c28cace6fe6b..93d5fbe2e4e3 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -912,7 +912,7 @@ void __put_page(struct page *page); void put_pages_list(struct list_head *pages); void split_page(struct page *page, unsigned int order); -void copy_huge_page(struct page *dst, struct page *src); +void folio_copy(struct folio *dst, struct folio *src); /* * Compound pages have a destructor function. Provide a diff --git a/mm/folio-compat.c b/mm/folio-compat.c index 3f00ad92d1ff..2ccd8f213fc4 100644 --- a/mm/folio-compat.c +++ b/mm/folio-compat.c @@ -64,4 +64,10 @@ void migrate_page_states(struct page *newpage, struct page *page) folio_migrate_flags(page_folio(newpage), page_folio(page)); } EXPORT_SYMBOL(migrate_page_states); + +void migrate_page_copy(struct page *newpage, struct page *page) +{ + folio_migrate_copy(page_folio(newpage), page_folio(page)); +} +EXPORT_SYMBOL(migrate_page_copy); #endif diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 95dc7b83381f..6378c1066459 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -5302,7 +5302,7 @@ int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm, *pagep = NULL; goto out; } - copy_huge_page(page, *pagep); + folio_copy(page_folio(page), page_folio(*pagep)); put_page(*pagep); *pagep = NULL; } diff --git a/mm/migrate.c b/mm/migrate.c index f6e0017ef0bf..433c453b47f9 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -614,16 +614,12 @@ void folio_migrate_flags(struct folio *newfolio, struct folio *folio) } EXPORT_SYMBOL(folio_migrate_flags); -void migrate_page_copy(struct page *newpage, struct page *page) +void folio_migrate_copy(struct folio *newfolio, struct folio *folio) { - if (PageHuge(page) || PageTransHuge(page)) - copy_huge_page(newpage, page); - else - copy_highpage(newpage, page); - - migrate_page_states(newpage, page); + folio_copy(newfolio, folio); + folio_migrate_flags(newfolio, folio); } -EXPORT_SYMBOL(migrate_page_copy); +EXPORT_SYMBOL(folio_migrate_copy); /************************************************************ * Migration functions @@ -651,7 +647,7 @@ int migrate_page(struct address_space *mapping, return rc; if (mode != MIGRATE_SYNC_NO_COPY) - migrate_page_copy(newpage, page); + folio_migrate_copy(newfolio, folio); else folio_migrate_flags(newfolio, folio); return MIGRATEPAGE_SUCCESS; diff --git a/mm/util.c b/mm/util.c index bf860838282c..e58151a61255 100644 --- a/mm/util.c +++ b/mm/util.c @@ -747,13 +747,26 @@ int __page_mapcount(struct page *page) } EXPORT_SYMBOL_GPL(__page_mapcount); -void copy_huge_page(struct page *dst, struct page *src) +/** + * folio_copy - Copy the contents of one folio to another. + * @dst: Folio to copy to. + * @src: Folio to copy from. + * + * The bytes in the folio represented by @src are copied to @dst. + * Assumes the caller has validated that @dst is at least as large as @src. + * Can be called in atomic context for order-0 folios, but if the folio is + * larger, it may sleep. + */ +void folio_copy(struct folio *dst, struct folio *src) { - unsigned i, nr = compound_nr(src); + long i = 0; + long nr = folio_nr_pages(src); - for (i = 0; i < nr; i++) { + for (;;) { + copy_highpage(folio_page(dst, i), folio_page(src, i)); + if (++i == nr) + break; cond_resched(); - copy_highpage(nth_page(dst, i), nth_page(src, i)); } } -- cgit