block: make rq_init() do a full memset()

This requires moving rq_init() from get_request() to blk_alloc_request().
The upside is that we can now require an rq_init() from any path that
wishes to hand the request to the block layer.

rq_init() will be exported for the code that uses struct request
without blk_get_request.

This is a preparation for large command support, which needs to
initialize struct request in a proper way (that is, just doing a
memset() will not work).

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

1 files changed, 1 insertions, 6 deletions

diff --git a/block/blk-barrier.c b/block/blk-barrier.c
index 55c5f1fc4f1f..722140ac175a 100644
--- a/block/blk-barrier.c
+++ b/block/blk-barrier.c
@@ -143,10 +143,8 @@ static void queue_flush(struct request_queue *q, unsigned which)
                 end_io = post_flush_end_io;
         }
 
-        rq->cmd_flags = REQ_HARDBARRIER;
         rq_init(q, rq);
-        rq->elevator_private = NULL;
-        rq->elevator_private2 = NULL;
+        rq->cmd_flags = REQ_HARDBARRIER;
         rq->rq_disk = q->bar_rq.rq_disk;
         rq->end_io = end_io;
         q->prepare_flush_fn(q, rq);
@@ -167,14 +165,11 @@ static inline struct request *start_ordered(struct request_queue *q,
         blkdev_dequeue_request(rq);
         q->orig_bar_rq = rq;
         rq = &q->bar_rq;
-        rq->cmd_flags = 0;
         rq_init(q, rq);
         if (bio_data_dir(q->orig_bar_rq->bio) == WRITE)
                 rq->cmd_flags |= REQ_RW;
         if (q->ordered & QUEUE_ORDERED_FUA)
                 rq->cmd_flags |= REQ_FUA;
-        rq->elevator_private = NULL;
-        rq->elevator_private2 = NULL;
         init_request_from_bio(rq, q->orig_bar_rq->bio);
         rq->end_io = bar_end_io;