Merge tag 'md-6.8-20240109' of https://git.kernel.org/pub/scm/linux/kernel/git/song/md into for-6.8/block

Pull MD fixes from Song:

"1. Sparse warning since v6.0, by Bart;
 2. /proc/mdstat regression since v6.7, by Yu Kuai."

* tag 'md-6.8-20240109' of https://git.kernel.org/pub/scm/linux/kernel/git/song/md:
  md/raid1: Use blk_opf_t for read and write operations
  md: Fix md_seq_ops() regressions

Author: axboe

drivers/md/md.c

@@ -8135,6 +8135,19 @@ 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;
@@ -8276,20 +8289,10 @@ 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)
@@ -8300,16 +8303,23 @@ 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;
 
@@ -8385,6 +8395,10 @@ 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);
 

drivers/md/raid1.c

@@ -1968,12 +1968,12 @@ static void end_sync_write(struct bio *bio)
 }
 
 static int r1_sync_page_io(struct md_rdev *rdev, sector_t sector,
-			   int sectors, struct page *page, int rw)
+			   int sectors, struct page *page, blk_opf_t rw)
 {
 	if (sync_page_io(rdev, sector, sectors << 9, page, rw, false))
 		/* success */
 		return 1;
-	if (rw == WRITE) {
+	if (rw == REQ_OP_WRITE) {
 		set_bit(WriteErrorSeen, &rdev->flags);
 		if (!test_and_set_bit(WantReplacement,
 				      &rdev->flags))
@@ -2090,7 +2090,7 @@ static int fix_sync_read_error(struct r1bio *r1_bio)
 			rdev = conf->mirrors[d].rdev;
 			if (r1_sync_page_io(rdev, sect, s,
 					    pages[idx],
-					    WRITE) == 0) {
+					    REQ_OP_WRITE) == 0) {
 				r1_bio->bios[d]->bi_end_io = NULL;
 				rdev_dec_pending(rdev, mddev);
 			}
@@ -2105,7 +2105,7 @@ static int fix_sync_read_error(struct r1bio *r1_bio)
 			rdev = conf->mirrors[d].rdev;
 			if (r1_sync_page_io(rdev, sect, s,
 					    pages[idx],
-					    READ) != 0)
+					    REQ_OP_READ) != 0)
 				atomic_add(s, &rdev->corrected_errors);
 		}
 		sectors -= s;
@@ -2321,7 +2321,7 @@ static void fix_read_error(struct r1conf *conf, struct r1bio *r1_bio)
 			    !test_bit(Faulty, &rdev->flags)) {
 				atomic_inc(&rdev->nr_pending);
 				r1_sync_page_io(rdev, sect, s,
-						conf->tmppage, WRITE);
+						conf->tmppage, REQ_OP_WRITE);
 				rdev_dec_pending(rdev, mddev);
 			}
 		}
@@ -2335,7 +2335,7 @@ static void fix_read_error(struct r1conf *conf, struct r1bio *r1_bio)
 			    !test_bit(Faulty, &rdev->flags)) {
 				atomic_inc(&rdev->nr_pending);
 				if (r1_sync_page_io(rdev, sect, s,
-						    conf->tmppage, READ)) {
+						conf->tmppage, REQ_OP_READ)) {
 					atomic_add(s, &rdev->corrected_errors);
 					pr_info("md/raid1:%s: read error corrected (%d sectors at %llu on %pg)\n",
 						mdname(mddev), s,