[PATCH 2/6] bcache: use bio_reuse instead of bio_reinit where applicable

[Christoph Hellwig]

Use the bio_reuse helper instead of rebuilding the bio_vecs and
size for bios that get reused for the same data.

Signed-off-by: Christoph Hellwig <h...@lst.de>
---
 drivers/md/bcache/request.c | 5 +----
 drivers/md/bcache/super.c   | 6 ++----
 2 files changed, 3 insertions(+), 8 deletions(-)

diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index ae67f5fa8047..3e699be2e79b 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -810,12 +810,9 @@ static void cached_dev_read_done(struct closure *cl)
         */
 
        if (s->iop.bio) {
-               bio_reset(s->iop.bio);
+               bio_reuse(s->iop.bio, s->insert_bio_sectors << 9);
                s->iop.bio->bi_iter.bi_sector = 
s->cache_miss->bi_iter.bi_sector;
                bio_copy_dev(s->iop.bio, s->cache_miss);
-               s->iop.bio->bi_iter.bi_size = s->insert_bio_sectors << 9;
-               bch_bio_map(s->iop.bio, NULL);
-
                bio_copy_data(s->cache_miss, s->iop.bio);
 
                bio_put(s->cache_miss);
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index a31e55bcc4e5..56692a451aeb 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -205,9 +205,7 @@ static void __write_super(struct cache_sb *sb, struct bio 
*bio)
        unsigned i;
 
        bio->bi_iter.bi_sector  = SB_SECTOR;
-       bio->bi_iter.bi_size    = SB_SIZE;
        bio_set_op_attrs(bio, REQ_OP_WRITE, REQ_SYNC|REQ_META);
-       bch_bio_map(bio, NULL);
 
        out->offset             = cpu_to_le64(sb->offset);
        out->version            = cpu_to_le64(sb->version);
@@ -249,7 +247,7 @@ void bch_write_bdev_super(struct cached_dev *dc, struct 
closure *parent)
        down(&dc->sb_write_mutex);
        closure_init(cl, parent);
 
-       bio_reset(bio);
+       bio_reuse(bio, SB_SIZE);
        bio_set_dev(bio, dc->bdev);
        bio->bi_end_io  = write_bdev_super_endio;
        bio->bi_private = dc;
@@ -298,7 +296,7 @@ void bcache_write_super(struct cache_set *c)
 
                SET_CACHE_SYNC(&ca->sb, CACHE_SYNC(&c->sb));
 
-               bio_reset(bio);
+               bio_reuse(bio, SB_SIZE);
                bio_set_dev(bio, ca->bdev);
                bio->bi_end_io  = write_super_endio;
                bio->bi_private = ca;
-- 
2.17.1