[PATCH 1/2] mm, frontswap: Fix frontswap_map issue with THP

[Hui Zhu]

Shrink will try to use frontswap interface store the THP as a normal
page in __frontswap_store:
	if (ret == 0) {
		__frontswap_set(sis, offset);
		inc_frontswap_succ_stores();
	} else {
It should set all bits with THP.

This commit set all bits with THP.

Signed-off-by: Hui Zhu <teawaterz@xxxxxxxxxxxxxxxxx>
---
 mm/frontswap.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/mm/frontswap.c b/mm/frontswap.c
index 60bb20e..f07ea63 100644
--- a/mm/frontswap.c
+++ b/mm/frontswap.c
@@ -274,8 +274,12 @@ int __frontswap_store(struct page *page)
 			break;
 	}
 	if (ret == 0) {
-		__frontswap_set(sis, offset);
-		inc_frontswap_succ_stores();
+		int i, nr = hpage_nr_pages(page);
+
+		for (i = 0; i < nr; i++) {
+			__frontswap_set(sis, offset + i);
+			inc_frontswap_succ_stores();
+		}
 	} else {
 		inc_frontswap_failed_stores();
 	}
-- 
2.7.4