Merge tag 'block-5.15-2021-10-17' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
 "Bigger than usual for this point in time, the majority is fixing some
  issues around BDI lifetimes with the move from the request_queue to
  the disk in this release. In detail:

   - Series on draining fs IO for del_gendisk() (Christoph)

   - NVMe pull request via Christoph:
        - fix the abort command id (Keith Busch)
        - nvme: fix per-namespace chardev deletion (Adam Manzanares)

   - brd locking scope fix (Tetsuo)

   - BFQ fix (Paolo)"

* tag 'block-5.15-2021-10-17' of git://git.kernel.dk/linux-block:
  block, bfq: reset last_bfqq_created on group change
  block: warn when putting the final reference on a registered disk
  brd: reduce the brd_devices_mutex scope
  kyber: avoid q->disk dereferences in trace points
  block: keep q_usage_counter in atomic mode after del_gendisk
  block: drain file system I/O on del_gendisk
  block: split bio_queue_enter from blk_queue_enter
  block: factor out a blk_try_enter_queue helper
  block: call submit_bio_checks under q_usage_counter
  nvme: fix per-namespace chardev deletion
  block/rnbd-clt-sysfs: fix a couple uninitialized variable bugs
  nvme-pci: Fix abort command id

2 files changed, 25 insertions, 23 deletions

diff --git a/drivers/block/brd.c b/drivers/block/brd.c
index 58ec167aa018..530b31240203 100644
--- a/drivers/block/brd.c
+++ b/drivers/block/brd.c
@@ -373,10 +373,22 @@ static int brd_alloc(int i)
 	struct gendisk *disk;
 	char buf[DISK_NAME_LEN];
 
+	mutex_lock(&brd_devices_mutex);
+	list_for_each_entry(brd, &brd_devices, brd_list) {
+		if (brd->brd_number == i) {
+			mutex_unlock(&brd_devices_mutex);
+			return -EEXIST;
+		}
+	}
 	brd = kzalloc(sizeof(*brd), GFP_KERNEL);
-	if (!brd)
+	if (!brd) {
+		mutex_unlock(&brd_devices_mutex);
 		return -ENOMEM;
+	}
 	brd->brd_number		= i;
+	list_add_tail(&brd->brd_list, &brd_devices);
+	mutex_unlock(&brd_devices_mutex);
+
 	spin_lock_init(&brd->brd_lock);
 	INIT_RADIX_TREE(&brd->brd_pages, GFP_ATOMIC);
 
@@ -411,37 +423,30 @@ static int brd_alloc(int i)
 	blk_queue_flag_set(QUEUE_FLAG_NONROT, disk->queue);
 	blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, disk->queue);
 	add_disk(disk);
-	list_add_tail(&brd->brd_list, &brd_devices);
 
 	return 0;
 
 out_free_dev:
+	mutex_lock(&brd_devices_mutex);
+	list_del(&brd->brd_list);
+	mutex_unlock(&brd_devices_mutex);
 	kfree(brd);
 	return -ENOMEM;
 }
 
 static void brd_probe(dev_t dev)
 {
-	int i = MINOR(dev) / max_part;
-	struct brd_device *brd;
-
-	mutex_lock(&brd_devices_mutex);
-	list_for_each_entry(brd, &brd_devices, brd_list) {
-		if (brd->brd_number == i)
-			goto out_unlock;
-	}
-
-	brd_alloc(i);
-out_unlock:
-	mutex_unlock(&brd_devices_mutex);
+	brd_alloc(MINOR(dev) / max_part);
 }
 
 static void brd_del_one(struct brd_device *brd)
 {
-	list_del(&brd->brd_list);
 	del_gendisk(brd->brd_disk);
 	blk_cleanup_disk(brd->brd_disk);
 	brd_free_pages(brd);
+	mutex_lock(&brd_devices_mutex);
+	list_del(&brd->brd_list);
+	mutex_unlock(&brd_devices_mutex);
 	kfree(brd);
 }
 
@@ -491,25 +496,21 @@ static int __init brd_init(void)
 
 	brd_debugfs_dir = debugfs_create_dir("ramdisk_pages", NULL);
 
-	mutex_lock(&brd_devices_mutex);
 	for (i = 0; i < rd_nr; i++) {
 		err = brd_alloc(i);
 		if (err)
 			goto out_free;
 	}
 
-	mutex_unlock(&brd_devices_mutex);
-
 	pr_info("brd: module loaded\n");
 	return 0;
 
 out_free:
+	unregister_blkdev(RAMDISK_MAJOR, "ramdisk");
 	debugfs_remove_recursive(brd_debugfs_dir);
 
 	list_for_each_entry_safe(brd, next, &brd_devices, brd_list)
 		brd_del_one(brd);
-	mutex_unlock(&brd_devices_mutex);
-	unregister_blkdev(RAMDISK_MAJOR, "ramdisk");
 
 	pr_info("brd: module NOT loaded !!!\n");
 	return err;
@@ -519,13 +520,12 @@ static void __exit brd_exit(void)
 {
 	struct brd_device *brd, *next;
 
+	unregister_blkdev(RAMDISK_MAJOR, "ramdisk");
 	debugfs_remove_recursive(brd_debugfs_dir);
 
 	list_for_each_entry_safe(brd, next, &brd_devices, brd_list)
 		brd_del_one(brd);
 
-	unregister_blkdev(RAMDISK_MAJOR, "ramdisk");
-
 	pr_info("brd: module unloaded\n");
 }
 
diff --git a/drivers/block/rnbd/rnbd-clt-sysfs.c b/drivers/block/rnbd/rnbd-clt-sysfs.c
index 4b93fd83bf79..44e45af00e83 100644
--- a/drivers/block/rnbd/rnbd-clt-sysfs.c
+++ b/drivers/block/rnbd/rnbd-clt-sysfs.c
@@ -71,8 +71,10 @@ static int rnbd_clt_parse_map_options(const char *buf, size_t max_path_cnt,
 	int opt_mask = 0;
 	int token;
 	int ret = -EINVAL;
-	int i, dest_port, nr_poll_queues;
+	int nr_poll_queues = 0;
+	int dest_port = 0;
 	int p_cnt = 0;
+	int i;
 
 	options = kstrdup(buf, GFP_KERNEL);
 	if (!options)