2 files changed, 23 insertions, 1 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 330addfe9b77..818313e277e7 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -4627,6 +4627,7 @@ static int do_md_run(mddev_t *mddev)
         }
         set_capacity(mddev->gendisk, mddev->array_sectors);
         revalidate_disk(mddev->gendisk);
+        mddev->changed = 1;
         kobject_uevent(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE);
 out:
         return err;
@@ -4715,6 +4716,7 @@ static void md_clean(mddev_t *mddev)
         mddev->sync_speed_min = mddev->sync_speed_max = 0;
         mddev->recovery = 0;
         mddev->in_sync = 0;
+        mddev->changed = 0;
         mddev->degraded = 0;
         mddev->safemode = 0;
         mddev->bitmap_info.offset = 0;
@@ -4830,6 +4832,7 @@ static int do_md_stop(mddev_t * mddev, int mode, int is_open)
 
                 set_capacity(disk, 0);
                 mutex_unlock(&mddev->open_mutex);
+                mddev->changed = 1;
                 revalidate_disk(disk);
 
                 if (mddev->ro)
@@ -6014,7 +6017,7 @@ static int md_open(struct block_device *bdev, fmode_t mode)
         atomic_inc(&mddev->openers);
         mutex_unlock(&mddev->open_mutex);
 
-        check_disk_size_change(mddev->gendisk, bdev);
+        check_disk_change(bdev);
  out:
         return err;
 }
@@ -6029,6 +6032,21 @@ static int md_release(struct gendisk *disk, fmode_t mode)
 
         return 0;
 }
+
+static int md_media_changed(struct gendisk *disk)
+{
+        mddev_t *mddev = disk->private_data;
+
+        return mddev->changed;
+}
+
+static int md_revalidate(struct gendisk *disk)
+{
+        mddev_t *mddev = disk->private_data;
+
+        mddev->changed = 0;
+        return 0;
+}
 static const struct block_device_operations md_fops =
 {
         .owner          = THIS_MODULE,
@@ -6039,6 +6057,8 @@ static const struct block_device_operations md_fops =
         .compat_ioctl   = md_compat_ioctl,
 #endif
         .getgeo         = md_getgeo,
+        .media_changed  = md_media_changed,
+        .revalidate_disk= md_revalidate,
 };
 
 static int md_thread(void * arg)
diff --git a/drivers/md/md.h b/drivers/md/md.h
index 7e90b8593b2a..12215d437fcc 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -274,6 +274,8 @@ struct mddev_s
         atomic_t                        active;         /* general refcount */
         atomic_t                        openers;        /* number of active opens */
 
+        int                             changed;        /* True if we might need to
+                                                         * reread partition info */
         int                             degraded;       /* whether md should consider
                                                          * adding a spare
                                                          */