Merge tag 'for-linus-20190323' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
 "A set of fixes/changes that should go into this series. This contains:

   - Kernel doc / comment updates (Bart, Shenghui)

   - Un-export of core-only used function (Bart)

   - Fix race on loop file access (Dongli)

   - pf/pcd queue cleanup fixes (me)

   - Use appropriate helper for RESTART bit set (Yufen)

   - Use named identifier for classic poll (Yufen)"

* tag 'for-linus-20190323' of git://git.kernel.dk/linux-block:
  sbitmap: trivial - update comment for sbitmap_deferred_clear_bit
  blkcg: Fix kernel-doc warnings
  blk-iolatency: #include "blk.h"
  block: Unexport blk_mq_add_to_requeue_list()
  block: add BLK_MQ_POLL_CLASSIC for hybrid poll and return EINVAL for unexpected value
  blk-mq: remove unused 'nr_expired' from blk_mq_hw_ctx
  loop: access lo_backing_file only when the loop device is Lo_bound
  blk-mq: use blk_mq_sched_mark_restart_hctx to set RESTART
  paride/pcd: cleanup queues when detection fails
  paride/pf: cleanup queues when detection fails

5 files changed, 18 insertions, 14 deletions

diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 77f37ef8ef06..617a2b3f7582 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -1736,8 +1736,8 @@ out:
 
 /**
  * blkcg_schedule_throttle - this task needs to check for throttling
- * @q - the request queue IO was submitted on
- * @use_memdelay - do we charge this to memory delay for PSI
+ * @q: the request queue IO was submitted on
+ * @use_memdelay: do we charge this to memory delay for PSI
  *
  * This is called by the IO controller when we know there's delay accumulated
  * for the blkg for this task.  We do not pass the blkg because there are places
@@ -1769,8 +1769,9 @@ void blkcg_schedule_throttle(struct request_queue *q, bool use_memdelay)
 
 /**
  * blkcg_add_delay - add delay to this blkg
- * @now - the current time in nanoseconds
- * @delta - how many nanoseconds of delay to add
+ * @blkg: blkg of interest
+ * @now: the current time in nanoseconds
+ * @delta: how many nanoseconds of delay to add
  *
  * Charge @delta to the blkg's current delay accumulation.  This is used to
  * throttle tasks if an IO controller thinks we need more throttling.
diff --git a/block/blk-iolatency.c b/block/blk-iolatency.c
index 2620baa1f699..507212d75ee2 100644
--- a/block/blk-iolatency.c
+++ b/block/blk-iolatency.c
@@ -75,6 +75,7 @@
 #include <linux/blk-mq.h>
 #include "blk-rq-qos.h"
 #include "blk-stat.h"
+#include "blk.h"
 
 #define DEFAULT_SCALE_COOKIE 1000000U
 
diff --git a/block/blk-mq.c b/block/blk-mq.c
index a9c181603cbd..70b210a308c4 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -782,7 +782,6 @@ void blk_mq_add_to_requeue_list(struct request *rq, bool at_head,
 	if (kick_requeue_list)
 		blk_mq_kick_requeue_list(q);
 }
-EXPORT_SYMBOL(blk_mq_add_to_requeue_list);
 
 void blk_mq_kick_requeue_list(struct request_queue *q)
 {
@@ -1093,8 +1092,7 @@ static bool blk_mq_mark_tag_wait(struct blk_mq_hw_ctx *hctx,
 	bool ret;
 
 	if (!(hctx->flags & BLK_MQ_F_TAG_SHARED)) {
-		if (!test_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state))
-			set_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state);
+		blk_mq_sched_mark_restart_hctx(hctx);
 
 		/*
 		 * It's possible that a tag was freed in the window between the
@@ -2857,7 +2855,7 @@ struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
 	/*
 	 * Default to classic polling
 	 */
-	q->poll_nsec = -1;
+	q->poll_nsec = BLK_MQ_POLL_CLASSIC;
 
 	blk_mq_init_cpu_queues(q, set->nr_hw_queues);
 	blk_mq_add_queue_tag_set(set, q);
@@ -3392,7 +3390,7 @@ static bool blk_mq_poll_hybrid(struct request_queue *q,
 {
 	struct request *rq;
 
-	if (q->poll_nsec == -1)
+	if (q->poll_nsec == BLK_MQ_POLL_CLASSIC)
 		return false;
 
 	if (!blk_qc_t_is_internal(cookie))
diff --git a/block/blk-mq.h b/block/blk-mq.h
index c11353a3749d..0ed8e5a8729f 100644
--- a/block/blk-mq.h
+++ b/block/blk-mq.h
@@ -41,6 +41,8 @@ void blk_mq_free_queue(struct request_queue *q);
 int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr);
 void blk_mq_wake_waiters(struct request_queue *q);
 bool blk_mq_dispatch_rq_list(struct request_queue *, struct list_head *, bool);
+void blk_mq_add_to_requeue_list(struct request *rq, bool at_head,
+				bool kick_requeue_list);
 void blk_mq_flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list);
 bool blk_mq_get_driver_tag(struct request *rq);
 struct request *blk_mq_dequeue_from_ctx(struct blk_mq_hw_ctx *hctx,
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index 59685918167e..422327089e0f 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -360,8 +360,8 @@ static ssize_t queue_poll_delay_show(struct request_queue *q, char *page)
 {
 	int val;
 
-	if (q->poll_nsec == -1)
-		val = -1;
+	if (q->poll_nsec == BLK_MQ_POLL_CLASSIC)
+		val = BLK_MQ_POLL_CLASSIC;
 	else
 		val = q->poll_nsec / 1000;
 
@@ -380,10 +380,12 @@ static ssize_t queue_poll_delay_store(struct request_queue *q, const char *page,
 	if (err < 0)
 		return err;
 
-	if (val == -1)
-		q->poll_nsec = -1;
-	else
+	if (val == BLK_MQ_POLL_CLASSIC)
+		q->poll_nsec = BLK_MQ_POLL_CLASSIC;
+	else if (val >= 0)
 		q->poll_nsec = val * 1000;
+	else
+		return -EINVAL;
 
 	return count;
 }