blk-mq: Make it safe to quiesce and unquiesce from an interrupt handler

[karo-tx-linux.git] / block / blk-mq.c

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 1c4f1f4978c6f0934a04c6a4e493e17a2b9c60f9..2caac30e128a2a989d717a6e668dc3402ec25de4 100644 (file)
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -153,6 +153,20 @@ void blk_mq_unfreeze_queue(struct request_queue *q)
 }
 EXPORT_SYMBOL_GPL(blk_mq_unfreeze_queue);
 
+/*
+ * FIXME: replace the scsi_internal_device_*block_nowait() calls in the
+ * mpt3sas driver such that this function can be removed.
+ */
+void blk_mq_quiesce_queue_nowait(struct request_queue *q)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave(q->queue_lock, flags);
+       queue_flag_set(QUEUE_FLAG_QUIESCED, q);
+       spin_unlock_irqrestore(q->queue_lock, flags);
+}
+EXPORT_SYMBOL_GPL(blk_mq_quiesce_queue_nowait);
+
 /**
  * blk_mq_quiesce_queue() - wait until all ongoing dispatches have finished
  * @q: request queue.
@@ -190,9 +204,11 @@ EXPORT_SYMBOL_GPL(blk_mq_quiesce_queue);
  */
 void blk_mq_unquiesce_queue(struct request_queue *q)
 {
-       spin_lock_irq(q->queue_lock);
+       unsigned long flags;
+
+       spin_lock_irqsave(q->queue_lock, flags);
        queue_flag_clear(QUEUE_FLAG_QUIESCED, q);
-       spin_unlock_irq(q->queue_lock);
+       spin_unlock_irqrestore(q->queue_lock, flags);
 
        /* dispatch requests which are inserted during quiescing */
        blk_mq_run_hw_queues(q, true);