bcache: Advertise that flushes are supported

Whoops - bcache's flush/FUA was mostly correct, but flushes get filtered
out unless we say we support them...

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10

2 files changed, 9 insertions, 1 deletions

diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index b6e74d3c8faf..786a1a4f74d8 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -488,6 +488,12 @@ static void bch_insert_data_loop(struct closure *cl)
                 bch_queue_gc(op->c);
         }
 
+        /*
+         * Journal writes are marked REQ_FLUSH; if the original write was a
+         * flush, it'll wait on the journal write.
+         */
+        bio->bi_rw &= ~(REQ_FLUSH|REQ_FUA);
+
         do {
                 unsigned i;
                 struct bkey *k;
@@ -710,7 +716,7 @@ static struct search *search_alloc(struct bio *bio, struct bcache_device *d)
         s->task                 = current;
         s->orig_bio             = bio;
         s->write                = (bio->bi_rw & REQ_WRITE) != 0;
-        s->op.flush_journal     = (bio->bi_rw & REQ_FLUSH) != 0;
+        s->op.flush_journal     = (bio->bi_rw & (REQ_FLUSH|REQ_FUA)) != 0;
         s->op.skip              = (bio->bi_rw & REQ_DISCARD) != 0;
         s->recoverable          = 1;
         s->start_time           = jiffies;
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index cff2d182dfb0..728fdc673f31 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -806,6 +806,8 @@ static int bcache_device_init(struct bcache_device *d, unsigned block_size,
         set_bit(QUEUE_FLAG_NONROT,      &d->disk->queue->queue_flags);
         set_bit(QUEUE_FLAG_DISCARD,     &d->disk->queue->queue_flags);
 
+        blk_queue_flush(q, REQ_FLUSH|REQ_FUA);
+
         return 0;
 }