1 files changed, 29 insertions, 19 deletions

diff --git a/mm/page_io.c b/mm/page_io.c
index 9e362567d454..433df1263349 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -40,7 +40,7 @@ static struct bio *get_swap_bio(gfp_t gfp_flags,
 		bio->bi_iter.bi_sector <<= PAGE_SHIFT - 9;
 		bio->bi_end_io = end_io;
 
-		bio_add_page(bio, page, PAGE_SIZE * hpage_nr_pages(page), 0);
+		bio_add_page(bio, page, thp_size(page), 0);
 	}
 	return bio;
 }
@@ -85,7 +85,7 @@ static void swap_slot_free_notify(struct page *page)
 		return;
 
 	sis = page_swap_info(page);
-	if (!(sis->flags & SWP_BLKDEV))
+	if (data_race(!(sis->flags & SWP_BLKDEV)))
 		return;
 
 	/*
@@ -252,6 +252,16 @@ int swap_writepage(struct page *page, struct writeback_control *wbc)
 		unlock_page(page);
 		goto out;
 	}
+	/*
+	 * Arch code may have to preserve more data than just the page
+	 * contents, e.g. memory tags.
+	 */
+	ret = arch_prepare_to_swap(page);
+	if (ret) {
+		set_page_dirty(page);
+		unlock_page(page);
+		goto out;
+	}
 	if (frontswap_store(page) == 0) {
 		set_page_writeback(page);
 		unlock_page(page);
@@ -274,7 +284,7 @@ static inline void count_swpout_vm_event(struct page *page)
 	if (unlikely(PageTransHuge(page)))
 		count_vm_event(THP_SWPOUT);
 #endif
-	count_vm_events(PSWPOUT, hpage_nr_pages(page));
+	count_vm_events(PSWPOUT, thp_nr_pages(page));
 }
 
 #if defined(CONFIG_MEMCG) && defined(CONFIG_BLK_CGROUP)
@@ -302,7 +312,7 @@ int __swap_writepage(struct page *page, struct writeback_control *wbc,
 	struct swap_info_struct *sis = page_swap_info(page);
 
 	VM_BUG_ON_PAGE(!PageSwapCache(page), page);
-	if (sis->flags & SWP_FS) {
+	if (data_race(sis->flags & SWP_FS_OPS)) {
 		struct kiocb kiocb;
 		struct file *swap_file = sis->swap_file;
 		struct address_space *mapping = swap_file->f_mapping;
@@ -349,13 +359,11 @@ int __swap_writepage(struct page *page, struct writeback_control *wbc,
 		return 0;
 	}
 
-	ret = 0;
 	bio = get_swap_bio(GFP_NOIO, page, end_write_func);
 	if (bio == NULL) {
 		set_page_dirty(page);
 		unlock_page(page);
-		ret = -ENOMEM;
-		goto out;
+		return -ENOMEM;
 	}
 	bio->bi_opf = REQ_OP_WRITE | REQ_SWAP | wbc_to_write_flags(wbc);
 	bio_associate_blkg_from_page(bio, page);
@@ -363,8 +371,8 @@ int __swap_writepage(struct page *page, struct writeback_control *wbc,
 	set_page_writeback(page);
 	unlock_page(page);
 	submit_bio(bio);
-out:
-	return ret;
+
+	return 0;
 }
 
 int swap_readpage(struct page *page, bool synchronous)
@@ -393,7 +401,7 @@ int swap_readpage(struct page *page, bool synchronous)
 		goto out;
 	}
 
-	if (sis->flags & SWP_FS) {
+	if (data_race(sis->flags & SWP_FS_OPS)) {
 		struct file *swap_file = sis->swap_file;
 		struct address_space *mapping = swap_file->f_mapping;
 
@@ -403,15 +411,17 @@ int swap_readpage(struct page *page, bool synchronous)
 		goto out;
 	}
 
-	ret = bdev_read_page(sis->bdev, swap_page_sector(page), page);
-	if (!ret) {
-		if (trylock_page(page)) {
-			swap_slot_free_notify(page);
-			unlock_page(page);
-		}
+	if (sis->flags & SWP_SYNCHRONOUS_IO) {
+		ret = bdev_read_page(sis->bdev, swap_page_sector(page), page);
+		if (!ret) {
+			if (trylock_page(page)) {
+				swap_slot_free_notify(page);
+				unlock_page(page);
+			}
 
-		count_vm_event(PSWPIN);
-		goto out;
+			count_vm_event(PSWPIN);
+			goto out;
+		}
 	}
 
 	ret = 0;
@@ -455,7 +465,7 @@ int swap_set_page_dirty(struct page *page)
 {
 	struct swap_info_struct *sis = page_swap_info(page);
 
-	if (sis->flags & SWP_FS) {
+	if (data_race(sis->flags & SWP_FS_OPS)) {
 		struct address_space *mapping = sis->swap_file->f_mapping;
 
 		VM_BUG_ON_PAGE(!PageSwapCache(page), page);