bcache: FUA fixes

Journal writes need to be marked FUA, not just REQ_FLUSH. And btree node
writes have... weird ordering requirements.

Signed-off-by: Kent Overstreet <koverstreet@google.com>

1 files changed, 12 insertions, 1 deletions

diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index 17bd59704eba..bcdf1f782c3e 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -1035,8 +1035,19 @@ static void request_write(struct cached_dev *dc, struct search *s)
 
                 closure_bio_submit(bio, cl, s->d);
         } else {
-                s->op.cache_bio = bio;
                 bch_writeback_add(dc);
+
+                if (s->op.flush_journal) {
+                        /* Also need to send a flush to the backing device */
+                        s->op.cache_bio = bio_clone_bioset(bio, GFP_NOIO,
+                                                           dc->disk.bio_split);
+
+                        bio->bi_size = 0;
+                        bio->bi_vcnt = 0;
+                        closure_bio_submit(bio, cl, s->d);
+                } else {
+                        s->op.cache_bio = bio;
+                }
         }
 out:
         closure_call(&s->op.cl, bch_insert_data, NULL, cl);