diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index c7c5b2693fc96ac2033524c067648c470bede1e9..0f1b78b386491e3cbddd7bd5cbd3ff8a841dbf02 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -301,27 +301,18 @@ static void reschedule_retry(struct r10bio *r10_bio)
 static void raid_end_bio_io(struct r10bio *r10_bio)
 {
 	struct bio *bio = r10_bio->master_bio;
-	int done;
 	struct r10conf *conf = r10_bio->mddev->private;
 
-	if (bio->bi_phys_segments) {
-		unsigned long flags;
-		spin_lock_irqsave(&conf->device_lock, flags);
-		bio->bi_phys_segments--;
-		done = (bio->bi_phys_segments == 0);
-		spin_unlock_irqrestore(&conf->device_lock, flags);
-	} else
-		done = 1;
 	if (!test_bit(R10BIO_Uptodate, &r10_bio->state))
 		bio->bi_error = -EIO;
-	if (done) {
-		bio_endio(bio);
-		/*
-		 * Wake up any possible resync thread that waits for the device
-		 * to go idle.
-		 */
-		allow_barrier(conf);
-	}
+
+	bio_endio(bio);
+	/*
+	 * Wake up any possible resync thread that waits for the device
+	 * to go idle.
+	 */
+	allow_barrier(conf);
+
 	free_r10bio(r10_bio);
 }
 
@@ -985,6 +976,15 @@ static void wait_barrier(struct r10conf *conf)
 	spin_unlock_irq(&conf->resync_lock);
 }
 
+static void inc_pending(struct r10conf *conf)
+{
+	/* The current request requires multiple r10_bio, so
+	 * we need to increment the pending count.
+	 */
+	WARN_ON(!atomic_read(&conf->nr_pending));
+	atomic_inc(&conf->nr_pending);
+}
+
 static void allow_barrier(struct r10conf *conf)
 {
 	if ((atomic_dec_and_test(&conf->nr_pending)) ||
@@ -1162,12 +1162,8 @@ static void raid10_read_request(struct mddev *mddev, struct bio *bio,
 		sectors_handled = (r10_bio->sector + max_sectors
 				   - bio->bi_iter.bi_sector);
 		r10_bio->sectors = max_sectors;
-		spin_lock_irq(&conf->device_lock);
-		if (bio->bi_phys_segments == 0)
-			bio->bi_phys_segments = 2;
-		else
-			bio->bi_phys_segments++;
-		spin_unlock_irq(&conf->device_lock);
+		inc_pending(conf);
+		bio_inc_remaining(bio);
 		/*
 		 * Cannot call generic_make_request directly as that will be
 		 * queued in __generic_make_request and subsequent
@@ -1262,9 +1258,7 @@ static void raid10_write_request(struct mddev *mddev, struct bio *bio,
 	 * on which we have seen a write error, we want to avoid
 	 * writing to those blocks.  This potentially requires several
 	 * writes to write around the bad blocks.  Each set of writes
-	 * gets its own r10_bio with a set of bios attached.  The number
-	 * of r10_bios is recored in bio->bi_phys_segments just as with
-	 * the read case.
+	 * gets its own r10_bio with a set of bios attached.
 	 */
 
 	r10_bio->read_slot = -1; /* make sure repl_bio gets freed */
@@ -1495,15 +1489,9 @@ static void raid10_write_request(struct mddev *mddev, struct bio *bio,
 	 */
 
 	if (sectors_handled < bio_sectors(bio)) {
-		/* We need another r10_bio and it needs to be counted
-		 * in bio->bi_phys_segments.
-		 */
-		spin_lock_irq(&conf->device_lock);
-		if (bio->bi_phys_segments == 0)
-			bio->bi_phys_segments = 2;
-		else
-			bio->bi_phys_segments++;
-		spin_unlock_irq(&conf->device_lock);
+		/* We need another r10_bio and it needs to be counted */
+		inc_pending(conf);
+		bio_inc_remaining(bio);
 		one_write_done(r10_bio);
 		r10_bio = mempool_alloc(conf->r10bio_pool, GFP_NOIO);
 
@@ -1532,16 +1520,6 @@ static void __make_request(struct mddev *mddev, struct bio *bio)
 	r10_bio->sector = bio->bi_iter.bi_sector;
 	r10_bio->state = 0;
 
-	/*
-	 * We might need to issue multiple reads to different devices if there
-	 * are bad blocks around, so we keep track of the number of reads in
-	 * bio->bi_phys_segments.  If this is 0, there is only one r10_bio and
-	 * no locking will be needed when the request completes.  If it is
-	 * non-zero, then it is the number of not-completed requests.
-	 */
-	bio->bi_phys_segments = 0;
-	bio_clear_flag(bio, BIO_SEG_VALID);
-
 	if (bio_data_dir(bio) == READ)
 		raid10_read_request(mddev, bio, r10_bio);
 	else
@@ -2693,12 +2671,8 @@ static void handle_read_error(struct mddev *mddev, struct r10bio *r10_bio)
 			r10_bio->sector + max_sectors
 			- mbio->bi_iter.bi_sector;
 		r10_bio->sectors = max_sectors;
-		spin_lock_irq(&conf->device_lock);
-		if (mbio->bi_phys_segments == 0)
-			mbio->bi_phys_segments = 2;
-		else
-			mbio->bi_phys_segments++;
-		spin_unlock_irq(&conf->device_lock);
+		bio_inc_remaining(mbio);
+		inc_pending(conf);
 		generic_make_request(bio);
 
 		r10_bio = mempool_alloc(conf->r10bio_pool,