[PATCH 27/27] mm: page_io.c: use bio_get_base_vec()

[Ming Lei]

Signed-off-by: Ming Lei <tom.leiming@xxxxxxxxx>
---
 mm/page_io.c | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/mm/page_io.c b/mm/page_io.c
index 18aac78..b5a6baf 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -43,7 +43,14 @@ static struct bio *get_swap_bio(gfp_t gfp_flags,
 
 void end_swap_bio_write(struct bio *bio)
 {
-	struct page *page = bio->bi_io_vec[0].bv_page;
+	/*
+	 * Single bvec bio.
+	 *
+	 * For accessing page pointed to by the 1st bvec, it
+	 * works too after multipage bvecs.
+	 */
+	struct bio_vec *bvec = bio_get_base_vec(bio);
+	struct page *page = bvec->bv_page;
 
 	if (bio->bi_error) {
 		SetPageError(page);
@@ -116,7 +123,14 @@ static void swap_slot_free_notify(struct page *page)
 
 static void end_swap_bio_read(struct bio *bio)
 {
-	struct page *page = bio->bi_io_vec[0].bv_page;
+	/*
+	 * Single bvec bio.
+	 *
+	 * For accessing page pointed to by the 1st bvec, it
+	 * works too after multipage bvecs.
+	 */
+	struct bio_vec *bvec = bio_get_base_vec(bio);
+	struct page *page = bvec->bv_page;
 
 	if (bio->bi_error) {
 		SetPageError(page);
-- 
1.9.1