block: Add interface to abort queued requests

Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

block/blk-timeout.c

@@ -153,3 +153,25 @@ void blk_add_timer(struct request *req)
 	    time_before(expiry, q->timeout.expires))
 		mod_timer(&q->timeout, expiry);
 }
+
+/**
+ * blk_abort_queue -- Abort all request on given queue
+ * @queue:	pointer to queue
+ *
+ */
+void blk_abort_queue(struct request_queue *q)
+{
+	unsigned long flags;
+	struct request *rq, *tmp;
+
+	spin_lock_irqsave(q->queue_lock, flags);
+
+	elv_abort_queue(q);
+
+	list_for_each_entry_safe(rq, tmp, &q->timeout_list, timeout_list)
+		blk_abort_request(rq);
+
+	spin_unlock_irqrestore(q->queue_lock, flags);
+
+}
+EXPORT_SYMBOL_GPL(blk_abort_queue);

block/elevator.c

@@ -914,6 +914,19 @@ int elv_may_queue(struct request_queue *q, int rw)
 	return ELV_MQUEUE_MAY;
 }
 
+void elv_abort_queue(struct request_queue *q)
+{
+	struct request *rq;
+
+	while (!list_empty(&q->queue_head)) {
+		rq = list_entry_rq(q->queue_head.next);
+		rq->cmd_flags |= REQ_QUIET;
+		blk_add_trace_rq(q, rq, BLK_TA_ABORT);
+		end_queued_request(rq, 0);
+	}
+}
+EXPORT_SYMBOL(elv_abort_queue);
+
 void elv_completed_request(struct request_queue *q, struct request *rq)
 {
 	elevator_t *e = q->elevator;

include/linux/blkdev.h

@@ -788,6 +788,7 @@ extern int blk_end_request_callback(struct request *rq, int error,
 extern void blk_complete_request(struct request *);
 extern void __blk_complete_request(struct request *);
 extern void blk_abort_request(struct request *);
+extern void blk_abort_queue(struct request_queue *);
 
 /*
  * blk_end_request() takes bytes instead of sectors as a complete size.

include/linux/blktrace_api.h

@@ -48,6 +48,7 @@ enum blktrace_act {
 	__BLK_TA_SPLIT,			/* bio was split */
 	__BLK_TA_BOUNCE,		/* bio was bounced */
 	__BLK_TA_REMAP,			/* bio was remapped */
+	__BLK_TA_ABORT,			/* request aborted */
 };
 
 /*
@@ -78,6 +79,7 @@ enum blktrace_notify {
 #define BLK_TA_SPLIT		(__BLK_TA_SPLIT)
 #define BLK_TA_BOUNCE		(__BLK_TA_BOUNCE)
 #define BLK_TA_REMAP		(__BLK_TA_REMAP | BLK_TC_ACT(BLK_TC_QUEUE))
+#define BLK_TA_ABORT		(__BLK_TA_ABORT | BLK_TC_ACT(BLK_TC_QUEUE))
 
 #define BLK_TN_PROCESS		(__BLK_TN_PROCESS | BLK_TC_ACT(BLK_TC_NOTIFY))
 #define BLK_TN_TIMESTAMP	(__BLK_TN_TIMESTAMP | BLK_TC_ACT(BLK_TC_NOTIFY))

include/linux/elevator.h

@@ -112,6 +112,7 @@ extern struct request *elv_latter_request(struct request_queue *, struct request
 extern int elv_register_queue(struct request_queue *q);
 extern void elv_unregister_queue(struct request_queue *q);
 extern int elv_may_queue(struct request_queue *, int);
+extern void elv_abort_queue(struct request_queue *);
 extern void elv_completed_request(struct request_queue *, struct request *);
 extern int elv_set_request(struct request_queue *, struct request *, gfp_t);
 extern void elv_put_request(struct request_queue *, struct request *);