Merge branch 'for-4.9/block-irq' of git://git.kernel.dk/linux-block

[cascardo/linux.git] / drivers / block / loop.c

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 075377e..cbdb3b1 100644 (file)
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -510,14 +510,10 @@ static int lo_rw_aio(struct loop_device *lo, struct loop_cmd *cmd,
        return 0;
 }
 
-
-static inline int lo_rw_simple(struct loop_device *lo,
-               struct request *rq, loff_t pos, bool rw)
+static int do_req_filebacked(struct loop_device *lo, struct request *rq)
 {
        struct loop_cmd *cmd = blk_mq_rq_to_pdu(rq);
-
-       if (cmd->use_aio)
-               return lo_rw_aio(lo, cmd, pos, rw);
+       loff_t pos = ((loff_t) blk_rq_pos(rq) << 9) + lo->lo_offset;
 
        /*
         * lo_write_simple and lo_read_simple should have been covered
@@ -528,37 +524,30 @@ static inline int lo_rw_simple(struct loop_device *lo,
         * of the req at one time. And direct read IO doesn't need to
         * run flush_dcache_page().
         */
-       if (rw == WRITE)
-               return lo_write_simple(lo, rq, pos);
-       else
-               return lo_read_simple(lo, rq, pos);
-}
-
-static int do_req_filebacked(struct loop_device *lo, struct request *rq)
-{
-       loff_t pos;
-       int ret;
-
-       pos = ((loff_t) blk_rq_pos(rq) << 9) + lo->lo_offset;
-
-       if (op_is_write(req_op(rq))) {
-               if (req_op(rq) == REQ_OP_FLUSH)
-                       ret = lo_req_flush(lo, rq);
-               else if (req_op(rq) == REQ_OP_DISCARD)
-                       ret = lo_discard(lo, rq, pos);
-               else if (lo->transfer)
-                       ret = lo_write_transfer(lo, rq, pos);
+       switch (req_op(rq)) {
+       case REQ_OP_FLUSH:
+               return lo_req_flush(lo, rq);
+       case REQ_OP_DISCARD:
+               return lo_discard(lo, rq, pos);
+       case REQ_OP_WRITE:
+               if (lo->transfer)
+                       return lo_write_transfer(lo, rq, pos);
+               else if (cmd->use_aio)
+                       return lo_rw_aio(lo, cmd, pos, WRITE);
                else
-                       ret = lo_rw_simple(lo, rq, pos, WRITE);
-
-       } else {
+                       return lo_write_simple(lo, rq, pos);
+       case REQ_OP_READ:
                if (lo->transfer)
-                       ret = lo_read_transfer(lo, rq, pos);
+                       return lo_read_transfer(lo, rq, pos);
+               else if (cmd->use_aio)
+                       return lo_rw_aio(lo, cmd, pos, READ);
                else
-                       ret = lo_rw_simple(lo, rq, pos, READ);
+                       return lo_read_simple(lo, rq, pos);
+       default:
+               WARN_ON_ONCE(1);
+               return -EIO;
+               break;
        }
-
-       return ret;
 }
 
 struct switch_request {
@@ -1659,11 +1648,15 @@ static int loop_queue_rq(struct blk_mq_hw_ctx *hctx,
        if (lo->lo_state != Lo_bound)
                return -EIO;
 
-       if (lo->use_dio && (req_op(cmd->rq) != REQ_OP_FLUSH ||
-           req_op(cmd->rq) == REQ_OP_DISCARD))
-               cmd->use_aio = true;
-       else
+       switch (req_op(cmd->rq)) {
+       case REQ_OP_FLUSH:
+       case REQ_OP_DISCARD:
                cmd->use_aio = false;
+               break;
+       default:
+               cmd->use_aio = lo->use_dio;
+               break;
+       }
 
        queue_kthread_work(&lo->worker, &cmd->work);
 
@@ -1710,7 +1703,6 @@ static int loop_init_request(void *data, struct request *rq,
 
 static struct blk_mq_ops loop_mq_ops = {
        .queue_rq       = loop_queue_rq,
-       .map_queue      = blk_mq_map_queue,
        .init_request   = loop_init_request,
 };