Merge tag 'block-6.1-2022-10-20' of git://git.kernel.dk/linux

Pull block fixes from Jens Axboe:

 - NVMe pull request via Christoph:
      - fix nvme-hwmon for DMA non-cohehrent architectures (Serge Semin)
      - add a nvme-hwmong maintainer (Christoph Hellwig)
      - fix error pointer dereference in error handling (Dan Carpenter)
      - fix invalid memory reference in nvmet_subsys_attr_qid_max_show
        (Daniel Wagner)
      - don't limit the DMA segment size in nvme-apple (Russell King)
      - fix workqueue MEM_RECLAIM flushing dependency (Sagi Grimberg)
      - disable write zeroes on various Kingston SSDs (Xander Li)

 - fix a memory leak with block device tracing (Ye)

 - flexible-array fix for ublk (Yushan)

 - document the ublk recovery feature from this merge window
   (ZiyangZhang)

 - remove dead bfq variable in struct (Yuwei)

 - error handling rq clearing fix (Yu)

 - add an IRQ safety check for the cached bio freeing (Pavel)

 - drbd bio cloning fix (Christoph)

* tag 'block-6.1-2022-10-20' of git://git.kernel.dk/linux:
  blktrace: remove unnessary stop block trace in 'blk_trace_shutdown'
  blktrace: fix possible memleak in '__blk_trace_remove'
  blktrace: introduce 'blk_trace_{start,stop}' helper
  bio: safeguard REQ_ALLOC_CACHE bio put
  block, bfq: remove unused variable for bfq_queue
  drbd: only clone bio if we have a backing device
  ublk_drv: use flexible-array member instead of zero-length array
  nvmet: fix invalid memory reference in nvmet_subsys_attr_qid_max_show
  nvmet: fix workqueue MEM_RECLAIM flushing dependency
  nvme-hwmon: kmalloc the NVME SMART log buffer
  nvme-hwmon: consistently ignore errors from nvme_hwmon_init
  nvme: add Guenther as nvme-hwmon maintainer
  nvme-apple: don't limit DMA segement size
  nvme-pci: disable write zeroes on various Kingston SSD
  nvme: fix error pointer dereference in error handling
  Documentation: document ublk user recovery feature
  blk-mq: fix null pointer dereference in blk_mq_clear_rq_mapping()

1 files changed, 39 insertions, 43 deletions

diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index 7f5eb295fe19..a995ea1ef849 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -346,8 +346,40 @@ static void put_probe_ref(void)
 	mutex_unlock(&blk_probe_mutex);
 }
 
+static int blk_trace_start(struct blk_trace *bt)
+{
+	if (bt->trace_state != Blktrace_setup &&
+	    bt->trace_state != Blktrace_stopped)
+		return -EINVAL;
+
+	blktrace_seq++;
+	smp_mb();
+	bt->trace_state = Blktrace_running;
+	raw_spin_lock_irq(&running_trace_lock);
+	list_add(&bt->running_list, &running_trace_list);
+	raw_spin_unlock_irq(&running_trace_lock);
+	trace_note_time(bt);
+
+	return 0;
+}
+
+static int blk_trace_stop(struct blk_trace *bt)
+{
+	if (bt->trace_state != Blktrace_running)
+		return -EINVAL;
+
+	bt->trace_state = Blktrace_stopped;
+	raw_spin_lock_irq(&running_trace_lock);
+	list_del_init(&bt->running_list);
+	raw_spin_unlock_irq(&running_trace_lock);
+	relay_flush(bt->rchan);
+
+	return 0;
+}
+
 static void blk_trace_cleanup(struct request_queue *q, struct blk_trace *bt)
 {
+	blk_trace_stop(bt);
 	synchronize_rcu();
 	blk_trace_free(q, bt);
 	put_probe_ref();
@@ -362,8 +394,7 @@ static int __blk_trace_remove(struct request_queue *q)
 	if (!bt)
 		return -EINVAL;
 
-	if (bt->trace_state != Blktrace_running)
-		blk_trace_cleanup(q, bt);
+	blk_trace_cleanup(q, bt);
 
 	return 0;
 }
@@ -658,7 +689,6 @@ static int compat_blk_trace_setup(struct request_queue *q, char *name,
 
 static int __blk_trace_startstop(struct request_queue *q, int start)
 {
-	int ret;
 	struct blk_trace *bt;
 
 	bt = rcu_dereference_protected(q->blk_trace,
@@ -666,36 +696,10 @@ static int __blk_trace_startstop(struct request_queue *q, int start)
 	if (bt == NULL)
 		return -EINVAL;
 
-	/*
-	 * For starting a trace, we can transition from a setup or stopped
-	 * trace. For stopping a trace, the state must be running
-	 */
-	ret = -EINVAL;
-	if (start) {
-		if (bt->trace_state == Blktrace_setup ||
-		    bt->trace_state == Blktrace_stopped) {
-			blktrace_seq++;
-			smp_mb();
-			bt->trace_state = Blktrace_running;
-			raw_spin_lock_irq(&running_trace_lock);
-			list_add(&bt->running_list, &running_trace_list);
-			raw_spin_unlock_irq(&running_trace_lock);
-
-			trace_note_time(bt);
-			ret = 0;
-		}
-	} else {
-		if (bt->trace_state == Blktrace_running) {
-			bt->trace_state = Blktrace_stopped;
-			raw_spin_lock_irq(&running_trace_lock);
-			list_del_init(&bt->running_list);
-			raw_spin_unlock_irq(&running_trace_lock);
-			relay_flush(bt->rchan);
-			ret = 0;
-		}
-	}
-
-	return ret;
+	if (start)
+		return blk_trace_start(bt);
+	else
+		return blk_trace_stop(bt);
 }
 
 int blk_trace_startstop(struct request_queue *q, int start)
@@ -772,10 +776,8 @@ int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg)
 void blk_trace_shutdown(struct request_queue *q)
 {
 	if (rcu_dereference_protected(q->blk_trace,
-				      lockdep_is_held(&q->debugfs_mutex))) {
-		__blk_trace_startstop(q, 0);
+				      lockdep_is_held(&q->debugfs_mutex)))
 		__blk_trace_remove(q);
-	}
 }
 
 #ifdef CONFIG_BLK_CGROUP
@@ -1614,13 +1616,7 @@ static int blk_trace_remove_queue(struct request_queue *q)
 	if (bt == NULL)
 		return -EINVAL;
 
-	if (bt->trace_state == Blktrace_running) {
-		bt->trace_state = Blktrace_stopped;
-		raw_spin_lock_irq(&running_trace_lock);
-		list_del_init(&bt->running_list);
-		raw_spin_unlock_irq(&running_trace_lock);
-		relay_flush(bt->rchan);
-	}
+	blk_trace_stop(bt);
 
 	put_probe_ref();
 	synchronize_rcu();