md: suspend i/o during runtime blk_integrity_unregister

Synchronize pending i/o against a change in the integrity profile to
avoid the possibility of spurious integrity errors.  Given linear_add()
is suspending the mddev before manipulating the mddev, do the same for
the other personalities.

Acked-by: NeilBrown <neilb@suse.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

4 files changed, 7 insertions, 0 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 7d07caceb349..714aa92db174 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -1994,6 +1994,7 @@ void md_integrity_add_rdev(struct md_rdev *rdev, struct mddev *mddev)
         if (bi_rdev && blk_integrity_compare(mddev->gendisk,
                                              rdev->bdev->bd_disk) >= 0)
                 return;
+        WARN_ON_ONCE(!mddev->suspended);
         printk(KERN_NOTICE "disabling data integrity on %s\n", mdname(mddev));
         blk_integrity_unregister(mddev->gendisk);
 }
diff --git a/drivers/md/multipath.c b/drivers/md/multipath.c
index d132f06afdd1..7331a80d89f1 100644
--- a/drivers/md/multipath.c
+++ b/drivers/md/multipath.c
@@ -264,7 +264,9 @@ static int multipath_add_disk(struct mddev *mddev, struct md_rdev *rdev)
                         spin_unlock_irq(&conf->device_lock);
                         rcu_assign_pointer(p->rdev, rdev);
                         err = 0;
+                        mddev_suspend(mddev);
                         md_integrity_add_rdev(rdev, mddev);
+                        mddev_resume(mddev);
                         break;
                 }
 
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 049df6c4a8cc..a881b111fa35 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -1621,7 +1621,9 @@ static int raid1_add_disk(struct mddev *mddev, struct md_rdev *rdev)
                         break;
                 }
         }
+        mddev_suspend(mddev);
         md_integrity_add_rdev(rdev, mddev);
+        mddev_resume(mddev);
         if (mddev->queue && blk_queue_discard(bdev_get_queue(rdev->bdev)))
                 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, mddev->queue);
         print_conf(conf);
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 7c99a4037715..6f0ec107996a 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -1736,7 +1736,9 @@ static int raid10_add_disk(struct mddev *mddev, struct md_rdev *rdev)
                 rcu_assign_pointer(p->rdev, rdev);
                 break;
         }
+        mddev_suspend(mddev);
         md_integrity_add_rdev(rdev, mddev);
+        mddev_resume(mddev);
         if (mddev->queue && blk_queue_discard(bdev_get_queue(rdev->bdev)))
                 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, mddev->queue);