md: factor do_md_run to separate accesses to ->gendisk

As part of relaxing the binding between an mddev and gendisk,
we separate do_md_run into two functions.
  md_run does all the work internal to md
  do_md_run calls md_run and makes and changes to gendisk
     that are required.

Signed-off-by: NeilBrown <neilb@suse.de>

1 files changed, 16 insertions, 8 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index f2b30019b1cb..e752332268d2 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -4297,11 +4297,10 @@ static void md_safemode_timeout(unsigned long data)
 
 static int start_dirty_degraded;
 
-static int do_md_run(mddev_t * mddev)
+static int md_run(mddev_t *mddev)
 {
         int err;
         mdk_rdev_t *rdev;
-        struct gendisk *disk;
         struct mdk_personality *pers;
 
         if (list_empty(&mddev->disks))
@@ -4366,8 +4365,6 @@ static int do_md_run(mddev_t * mddev)
                 sysfs_notify_dirent(rdev->sysfs_state);
         }
 
-        disk = mddev->gendisk;
-
         spin_lock(&pers_lock);
         pers = find_pers(mddev->level, mddev->clevel);
         if (!pers || !try_module_get(pers->owner)) {
@@ -4495,21 +4492,32 @@ static int do_md_run(mddev_t * mddev)
         if (mddev->flags)
                 md_update_sb(mddev, 0);
 
-        set_capacity(disk, mddev->array_sectors);
-
         md_wakeup_thread(mddev->thread);
         md_wakeup_thread(mddev->sync_thread); /* possibly kick off a reshape */
 
-        revalidate_disk(mddev->gendisk);
         md_new_event(mddev);
         sysfs_notify_dirent(mddev->sysfs_state);
         if (mddev->sysfs_action)
                 sysfs_notify_dirent(mddev->sysfs_action);
         sysfs_notify(&mddev->kobj, NULL, "degraded");
-        kobject_uevent(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE);
         return 0;
 }
 
+static int do_md_run(mddev_t *mddev)
+{
+        int err;
+
+        err = md_run(mddev);
+        if (err)
+                goto out;
+
+        set_capacity(mddev->gendisk, mddev->array_sectors);
+        revalidate_disk(mddev->gendisk);
+        kobject_uevent(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE);
+out:
+        return err;
+}
+
 static int restart_array(mddev_t *mddev)
 {
         struct gendisk *disk = mddev->gendisk;