mtd_blkdevs: dequeue in-flight request

mtd_blkdevs processes requests one-by-one synchronously from a kthread
and can be easily converted to dequeueing model.  Convert it.

[ Impact: dequeue in-flight request ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

1 files changed, 13 insertions, 4 deletions

diff --git a/drivers/mtd/mtd_blkdevs.c b/drivers/mtd/mtd_blkdevs.c
index 50c76a2ca76e..3e10442615d1 100644
--- a/drivers/mtd/mtd_blkdevs.c
+++ b/drivers/mtd/mtd_blkdevs.c
@@ -89,18 +89,22 @@ static int mtd_blktrans_thread(void *arg)
 {
         struct mtd_blktrans_ops *tr = arg;
         struct request_queue *rq = tr->blkcore_priv->rq;
+        struct request *req = NULL;
 
         /* we might get involved when memory gets low, so use PF_MEMALLOC */
         current->flags |= PF_MEMALLOC;
 
         spin_lock_irq(rq->queue_lock);
+
         while (!kthread_should_stop()) {
-                struct request *req;
                 struct mtd_blktrans_dev *dev;
                 int res;
 
-                req = elv_next_request(rq);
-
+                if (!req) {
+                        req = elv_next_request(rq);
+                        if (req)
+                                blkdev_dequeue_request(req);
+                }
                 if (!req) {
                         set_current_state(TASK_INTERRUPTIBLE);
                         spin_unlock_irq(rq->queue_lock);
@@ -120,8 +124,13 @@ static int mtd_blktrans_thread(void *arg)
 
                 spin_lock_irq(rq->queue_lock);
 
-                __blk_end_request_cur(req, res);
+                if (!__blk_end_request_cur(req, res))
+                        req = NULL;
         }
+
+        if (req)
+                __blk_end_request_all(req, -EIO);
+
         spin_unlock_irq(rq->queue_lock);
 
         return 0;