1 files changed, 32 insertions, 11 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index edf777f6fe56..e8d238885cd2 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -509,9 +509,9 @@ static inline int mddev_trylock(mddev_t * mddev)
 
 static struct attribute_group md_redundancy_group;
 
-static inline void mddev_unlock(mddev_t * mddev)
+static void mddev_unlock(mddev_t * mddev)
 {
-        if (mddev->pers == NULL && mddev->private) {
+        if (mddev->to_remove) {
                 /* These cannot be removed under reconfig_mutex as
                  * an access to the files will try to take reconfig_mutex
                  * while holding the file unremovable, which leads to
@@ -520,16 +520,20 @@ static inline void mddev_unlock(mddev_t * mddev)
                  * it while holding reconfig_mutex, and md_run can
                  * use it to wait for the remove to complete.
                  */
+                struct attribute_group *to_remove = mddev->to_remove;
+                mddev->to_remove = NULL;
                 mutex_lock(&mddev->open_mutex);
                 mutex_unlock(&mddev->reconfig_mutex);
 
-                sysfs_remove_group(&mddev->kobj, &md_redundancy_group);
-                if (mddev->private != (void*)1)
-                        sysfs_remove_group(&mddev->kobj, mddev->private);
-                if (mddev->sysfs_action)
-                        sysfs_put(mddev->sysfs_action);
-                mddev->sysfs_action = NULL;
-                mddev->private = NULL;
+                if (to_remove != &md_redundancy_group)
+                        sysfs_remove_group(&mddev->kobj, to_remove);
+                if (mddev->pers == NULL ||
+                    mddev->pers->sync_request == NULL) {
+                        sysfs_remove_group(&mddev->kobj, &md_redundancy_group);
+                        if (mddev->sysfs_action)
+                                sysfs_put(mddev->sysfs_action);
+                        mddev->sysfs_action = NULL;
+                }
                 mutex_unlock(&mddev->open_mutex);
         } else
                 mutex_unlock(&mddev->reconfig_mutex);
@@ -2996,6 +3000,23 @@ level_store(mddev_t *mddev, const char *buf, size_t len)
         /* Looks like we have a winner */
         mddev_suspend(mddev);
         mddev->pers->stop(mddev);
+        
+        if (mddev->pers->sync_request == NULL &&
+            pers->sync_request != NULL) {
+                /* need to add the md_redundancy_group */
+                if (sysfs_create_group(&mddev->kobj, &md_redundancy_group))
+                        printk(KERN_WARNING
+                               "md: cannot register extra attributes for %s\n",
+                               mdname(mddev));
+                mddev->sysfs_action = sysfs_get_dirent(mddev->kobj.sd, "sync_action");
+        }               
+        if (mddev->pers->sync_request != NULL &&
+            pers->sync_request == NULL) {
+                /* need to remove the md_redundancy_group */
+                if (mddev->to_remove == NULL)
+                        mddev->to_remove = &md_redundancy_group;
+        }
+
         module_put(mddev->pers->owner);
         /* Invalidate devices that are now superfluous */
         list_for_each_entry(rdev, &mddev->disks, same_set)
@@ -4550,8 +4571,8 @@ static int do_md_stop(mddev_t * mddev, int mode, int is_open)
                         mddev->queue->unplug_fn = NULL;
                         mddev->queue->backing_dev_info.congested_fn = NULL;
                         module_put(mddev->pers->owner);
-                        if (mddev->pers->sync_request && mddev->private == NULL)
-                                mddev->private = (void*)1;
+                        if (mddev->pers->sync_request && mddev->to_remove == NULL)
+                                mddev->to_remove = &md_redundancy_group;
                         mddev->pers = NULL;
                         /* tell userspace to handle 'inactive' */
                         sysfs_notify_dirent(mddev->sysfs_state);