[PATCH V4 24/45] btrfs: use segment_last_page to get bio's last page

[Ming Lei]

Preparing for supporting multipage bvec.

Cc: Chris Mason <c...@fb.com>
Cc: Josef Bacik <jba...@fb.com>
Cc: David Sterba <dste...@suse.com>
Cc: linux-bt...@vger.kernel.org
Signed-off-by: Ming Lei <ming....@redhat.com>
---
 fs/btrfs/compression.c | 5 ++++-
 fs/btrfs/extent_io.c   | 5 +++--
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index 15430c9fc6d7..1a62725a5f08 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -412,8 +412,11 @@ blk_status_t btrfs_submit_compressed_write(struct inode 
*inode, u64 start,
 static u64 bio_end_offset(struct bio *bio)
 {
        struct bio_vec *last = bio_last_bvec_all(bio);
+       struct bio_vec bv;
 
-       return page_offset(last->bv_page) + last->bv_len + last->bv_offset;
+       segment_last_page(last, &bv);
+
+       return page_offset(bv.bv_page) + bv.bv_len + bv.bv_offset;
 }
 
 static noinline int add_ra_bio_pages(struct inode *inode,
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 6984e0d5b00d..f466289b66a3 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2726,11 +2726,12 @@ static int __must_check submit_one_bio(struct bio *bio, 
int mirror_num,
 {
        blk_status_t ret = 0;
        struct bio_vec *bvec = bio_last_bvec_all(bio);
-       struct page *page = bvec->bv_page;
+       struct bio_vec bv;
        struct extent_io_tree *tree = bio->bi_private;
        u64 start;
 
-       start = page_offset(page) + bvec->bv_offset;
+       segment_last_page(bvec, &bv);
+       start = page_offset(bv.bv_page) + bv.bv_offset;
 
        bio->bi_private = NULL;
        bio_get(bio);
-- 
2.9.5