1 files changed, 36 insertions, 21 deletions

diff --git a/block/blk-core.c b/block/blk-core.c
index 034cbb2024f0..7e1523521c70 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -349,11 +349,13 @@ EXPORT_SYMBOL(blk_put_queue);
 /**
  * blk_drain_queue - drain requests from request_queue
  * @q: queue to drain
+ * @drain_all: whether to drain all requests or only the ones w/ ELVPRIV
  *
- * Drain ELV_PRIV requests from @q.  The caller is responsible for ensuring
- * that no new requests which need to be drained are queued.
+ * Drain requests from @q.  If @drain_all is set, all requests are drained.
+ * If not, only ELVPRIV requests are drained.  The caller is responsible
+ * for ensuring that no new requests which need to be drained are queued.
  */
-void blk_drain_queue(struct request_queue *q)
+void blk_drain_queue(struct request_queue *q, bool drain_all)
 {
         while (true) {
                 int nr_rqs;
@@ -361,9 +363,15 @@ void blk_drain_queue(struct request_queue *q)
                 spin_lock_irq(q->queue_lock);
 
                 elv_drain_elevator(q);
+                if (drain_all)
+                        blk_throtl_drain(q);
 
                 __blk_run_queue(q);
-                nr_rqs = q->rq.elvpriv;
+
+                if (drain_all)
+                        nr_rqs = q->rq.count[0] + q->rq.count[1];
+                else
+                        nr_rqs = q->rq.elvpriv;
 
                 spin_unlock_irq(q->queue_lock);
 
@@ -373,30 +381,40 @@ void blk_drain_queue(struct request_queue *q)
         }
 }
 
-/*
- * Note: If a driver supplied the queue lock, it is disconnected
- * by this function. The actual state of the lock doesn't matter
- * here as the request_queue isn't accessible after this point
- * (QUEUE_FLAG_DEAD is set) and no other requests will be queued.
+/**
+ * blk_cleanup_queue - shutdown a request queue
+ * @q: request queue to shutdown
+ *
+ * Mark @q DEAD, drain all pending requests, destroy and put it.  All
+ * future requests will be failed immediately with -ENODEV.
  */
 void blk_cleanup_queue(struct request_queue *q)
 {
-        /*
-         * We know we have process context here, so we can be a little
-         * cautious and ensure that pending block actions on this device
-         * are done before moving on. Going into this function, we should
-         * not have processes doing IO to this device.
-         */
-        blk_sync_queue(q);
+        spinlock_t *lock = q->queue_lock;
 
-        del_timer_sync(&q->backing_dev_info.laptop_mode_wb_timer);
+        /* mark @q DEAD, no new request or merges will be allowed afterwards */
         mutex_lock(&q->sysfs_lock);
         queue_flag_set_unlocked(QUEUE_FLAG_DEAD, q);
-        mutex_unlock(&q->sysfs_lock);
+
+        spin_lock_irq(lock);
+        queue_flag_set(QUEUE_FLAG_NOMERGES, q);
+        queue_flag_set(QUEUE_FLAG_NOXMERGES, q);
+        queue_flag_set(QUEUE_FLAG_DEAD, q);
 
         if (q->queue_lock != &q->__queue_lock)
                 q->queue_lock = &q->__queue_lock;
 
+        spin_unlock_irq(lock);
+        mutex_unlock(&q->sysfs_lock);
+
+        /* drain all requests queued before DEAD marking */
+        blk_drain_queue(q, true);
+
+        /* @q won't process any more request, flush async actions */
+        del_timer_sync(&q->backing_dev_info.laptop_mode_wb_timer);
+        blk_sync_queue(q);
+
+        /* @q is and will stay empty, shutdown and put */
         blk_put_queue(q);
 }
 EXPORT_SYMBOL(blk_cleanup_queue);
@@ -1509,9 +1527,6 @@ generic_make_request_checks(struct bio *bio)
                 goto end_io;
         }
 
-        if (unlikely(test_bit(QUEUE_FLAG_DEAD, &q->queue_flags)))
-                goto end_io;
-
         part = bio->bi_bdev->bd_part;
         if (should_fail_request(part, bio->bi_size) ||
             should_fail_request(&part_to_disk(part)->part0,