Merge tag 'md/4.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md

Pull MD fixes from Shaohua Li:

 - Several bug fixes for raid5-cache from Song Liu, mainly handle
   journal disk error

 - Fix bad block handling in choosing raid1 disk from Tomasz Majchrzak

 - Simplify external metadata array sysfs handling from Artur
   Paszkiewicz

 - Optimize raid0 discard handling from me, now raid0 will dispatch
   large discard IO directly to underlayer disks.

* tag 'md/4.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md:
  raid1: prefer disk without bad blocks
  md/r5cache: handle sync with data in write back cache
  md/r5cache: gracefully handle journal device errors for writeback mode
  md/raid1/10: avoid unnecessary locking
  md/raid5-cache: in r5l_do_submit_io(), submit io->split_bio first
  md/md0: optimize raid0 discard handling
  md: don't return -EAGAIN in md_allow_write for external metadata arrays
  md/raid5: make use of spin_lock_irq over local_irq_disable + spin_lock

1 files changed, 10 insertions, 11 deletions

diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 7ed59351fe97..af5056d56878 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -666,8 +666,11 @@ static int read_balance(struct r1conf *conf, struct r1bio *r1_bio, int *max_sect
 					break;
 			}
 			continue;
-		} else
+		} else {
+			if ((sectors > best_good_sectors) && (best_disk >= 0))
+				best_disk = -1;
 			best_good_sectors = sectors;
+		}
 
 		if (best_disk >= 0)
 			/* At least two disks to choose from so failfast is OK */
@@ -1529,17 +1532,16 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio,
 			plug = container_of(cb, struct raid1_plug_cb, cb);
 		else
 			plug = NULL;
-		spin_lock_irqsave(&conf->device_lock, flags);
 		if (plug) {
 			bio_list_add(&plug->pending, mbio);
 			plug->pending_cnt++;
 		} else {
+			spin_lock_irqsave(&conf->device_lock, flags);
 			bio_list_add(&conf->pending_bio_list, mbio);
 			conf->pending_count++;
-		}
-		spin_unlock_irqrestore(&conf->device_lock, flags);
-		if (!plug)
+			spin_unlock_irqrestore(&conf->device_lock, flags);
 			md_wakeup_thread(mddev->thread);
+		}
 	}
 
 	r1_bio_write_done(r1_bio);
@@ -3197,7 +3199,7 @@ static int raid1_reshape(struct mddev *mddev)
 	struct r1conf *conf = mddev->private;
 	int cnt, raid_disks;
 	unsigned long flags;
-	int d, d2, err;
+	int d, d2;
 
 	/* Cannot change chunk_size, layout, or level */
 	if (mddev->chunk_sectors != mddev->new_chunk_sectors ||
@@ -3209,11 +3211,8 @@ static int raid1_reshape(struct mddev *mddev)
 		return -EINVAL;
 	}
 
-	if (!mddev_is_clustered(mddev)) {
-		err = md_allow_write(mddev);
-		if (err)
-			return err;
-	}
+	if (!mddev_is_clustered(mddev))
+		md_allow_write(mddev);
 
 	raid_disks = mddev->raid_disks + mddev->delta_disks;