Merge tag 'for-6.8/block-2024-01-18' of git://git.kernel.dk/linux

Pull block fixes from Jens Axboe:

 - NVMe pull request via Keith:
      - tcp, fc, and rdma target fixes (Maurizio, Daniel, Hannes,
        Christoph)
      - discard fixes and improvements (Christoph)
      - timeout debug improvements (Keith, Max)
      - various cleanups (Daniel, Max, Giuxen)
      - trace event string fixes (Arnd)
      - shadow doorbell setup on reset fix (William)
      - a write zeroes quirk for SK Hynix (Jim)

 - MD pull request via Song:
      - Sparse warning since v6.0 (Bart)
      - /proc/mdstat regression since v6.7 (Yu Kuai)

 - Use symbolic error value (Christian)

 - IO Priority documentation update (Christian)

 - Fix for accessing queue limits without having entered the queue
   (Christoph, me)

 - Fix for loop dio support (Christoph)

 - Move null_blk off deprecated ida interface (Christophe)

 - Ensure nbd initializes full msghdr (Eric)

 - Fix for a regression with the folio conversion, which is now easier
   to hit because of an unrelated change (Matthew)

 - Remove redundant check in virtio-blk (Li)

 - Fix for a potential hang in sbitmap (Ming)

 - Fix for partial zone appending (Damien)

 - Misc changes and fixes (Bart, me, Kemeng, Dmitry)

* tag 'for-6.8/block-2024-01-18' of git://git.kernel.dk/linux: (45 commits)
  Documentation: block: ioprio: Update schedulers
  loop: fix the the direct I/O support check when used on top of block devices
  blk-mq: Remove the hctx 'run' debugfs attribute
  nbd: always initialize struct msghdr completely
  block: Fix iterating over an empty bio with bio_for_each_folio_all
  block: bio-integrity: fix kcalloc() arguments order
  virtio_blk: remove duplicate check if queue is broken in virtblk_done
  sbitmap: remove stale comment in sbq_calc_wake_batch
  block: Correct a documentation comment in blk-cgroup.c
  null_blk: Remove usage of the deprecated ida_simple_xx() API
  block: ensure we hold a queue reference when using queue limits
  blk-mq: rename blk_mq_can_use_cached_rq
  block: print symbolic error name instead of error code
  blk-mq: fix IO hang from sbitmap wakeup race
  nvmet-rdma: avoid circular locking dependency on install_queue()
  nvmet-tcp: avoid circular locking dependency on install_queue()
  nvme-pci: set doorbell config before unquiescing
  block: fix partial zone append completion handling in req_bio_endio()
  block/iocost: silence warning on 'last_period' potentially being unused
  md/raid1: Use blk_opf_t for read and write operations
  ...

1 files changed, 27 insertions, 13 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 0a2bd72a6d76..2266358d8074 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -8132,6 +8132,19 @@ static void status_unused(struct seq_file *seq)
 	seq_printf(seq, "\n");
 }
 
+static void status_personalities(struct seq_file *seq)
+{
+	struct md_personality *pers;
+
+	seq_puts(seq, "Personalities : ");
+	spin_lock(&pers_lock);
+	list_for_each_entry(pers, &pers_list, list)
+		seq_printf(seq, "[%s] ", pers->name);
+
+	spin_unlock(&pers_lock);
+	seq_puts(seq, "\n");
+}
+
 static int status_resync(struct seq_file *seq, struct mddev *mddev)
 {
 	sector_t max_sectors, resync, res;
@@ -8273,20 +8286,10 @@ static int status_resync(struct seq_file *seq, struct mddev *mddev)
 static void *md_seq_start(struct seq_file *seq, loff_t *pos)
 	__acquires(&all_mddevs_lock)
 {
-	struct md_personality *pers;
-
-	seq_puts(seq, "Personalities : ");
-	spin_lock(&pers_lock);
-	list_for_each_entry(pers, &pers_list, list)
-		seq_printf(seq, "[%s] ", pers->name);
-
-	spin_unlock(&pers_lock);
-	seq_puts(seq, "\n");
 	seq->poll_event = atomic_read(&md_event_count);
-
 	spin_lock(&all_mddevs_lock);
 
-	return seq_list_start(&all_mddevs, *pos);
+	return seq_list_start_head(&all_mddevs, *pos);
 }
 
 static void *md_seq_next(struct seq_file *seq, void *v, loff_t *pos)
@@ -8297,16 +8300,23 @@ static void *md_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 static void md_seq_stop(struct seq_file *seq, void *v)
 	__releases(&all_mddevs_lock)
 {
-	status_unused(seq);
 	spin_unlock(&all_mddevs_lock);
 }
 
 static int md_seq_show(struct seq_file *seq, void *v)
 {
-	struct mddev *mddev = list_entry(v, struct mddev, all_mddevs);
+	struct mddev *mddev;
 	sector_t sectors;
 	struct md_rdev *rdev;
 
+	if (v == &all_mddevs) {
+		status_personalities(seq);
+		if (list_empty(&all_mddevs))
+			status_unused(seq);
+		return 0;
+	}
+
+	mddev = list_entry(v, struct mddev, all_mddevs);
 	if (!mddev_get(mddev))
 		return 0;
 
@@ -8382,6 +8392,10 @@ static int md_seq_show(struct seq_file *seq, void *v)
 	}
 	spin_unlock(&mddev->lock);
 	spin_lock(&all_mddevs_lock);
+
+	if (mddev == list_last_entry(&all_mddevs, struct mddev, all_mddevs))
+		status_unused(seq);
+
 	if (atomic_dec_and_test(&mddev->active))
 		__mddev_put(mddev);