[PATCH V7 16/24] btrfs: use bvec_last_segment to get bio's last page

From: Ming Lei
Date: Wed Jun 27 2018 - 08:49:20 EST


Preparing for supporting multipage bvec.

Cc: Chris Mason <clm@xxxxxx>
Cc: Josef Bacik <jbacik@xxxxxx>
Cc: David Sterba <dsterba@xxxxxxxx>
Cc: linux-btrfs@xxxxxxxxxxxxxxx
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
---
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 d3e447b45bf7..22b9e0e56c7e 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -407,8 +407,11 @@ 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;
+ bvec_last_segment(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 cce6087d6880..0b5e07723f5f 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2728,11 +2728,12 @@ 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;
+ bvec_last_segment(bvec, &bv);
+ start = page_offset(bv.bv_page) + bv.bv_offset;

bio->bi_private = NULL;

--
2.9.5