Merge branches 'acpi_pad', 'acpica', 'apei-bugzilla-43282', 'battery', 'cpuidle-coupl...

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / block / blk-core.c

diff --git a/block/blk-core.c b/block/blk-core.c
index 3c923a7aeb56f1658142b091868c3c29ebffd3c5..93eb3e4f88ce78affc79c5ca6d8b7c7b0759be5a 100644 (file)
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -361,9 +361,10 @@ EXPORT_SYMBOL(blk_put_queue);
  */
 void blk_drain_queue(struct request_queue *q, bool drain_all)
 {
+       int i;
+
        while (true) {
                bool drain = false;
-               int i;
 
                spin_lock_irq(q->queue_lock);
 
@@ -408,6 +409,18 @@ void blk_drain_queue(struct request_queue *q, bool drain_all)
                        break;
                msleep(10);
        }
+
+       /*
+        * With queue marked dead, any woken up waiter will fail the
+        * allocation path, so the wakeup chaining is lost and we're
+        * left with hung waiters. We need to wake up those waiters.
+        */
+       if (q->request_fn) {
+               spin_lock_irq(q->queue_lock);
+               for (i = 0; i < ARRAY_SIZE(q->rq.wait); i++)
+                       wake_up_all(&q->rq.wait[i]);
+               spin_unlock_irq(q->queue_lock);
+       }
 }
 
 /**
@@ -467,7 +480,6 @@ void blk_cleanup_queue(struct request_queue *q)
        /* 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);
-
        spin_lock_irq(lock);
 
        /*
@@ -485,10 +497,6 @@ void blk_cleanup_queue(struct request_queue *q)
        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);
 
@@ -499,6 +507,11 @@ void blk_cleanup_queue(struct request_queue *q)
        del_timer_sync(&q->backing_dev_info.laptop_mode_wb_timer);
        blk_sync_queue(q);
 
+       spin_lock_irq(lock);
+       if (q->queue_lock != &q->__queue_lock)
+               q->queue_lock = &q->__queue_lock;
+       spin_unlock_irq(lock);
+
        /* @q is and will stay empty, shutdown and put */
        blk_put_queue(q);
 }