- /*
- * OK, now we've set up the new group. Time to make it active.
- *
- * Current kernels don't lock all allocations via lock_super(),
- * so we have to be safe wrt. concurrent accesses the group
- * data. So we need to be careful to set all of the relevant
- * group descriptor data etc. *before* we enable the group.
- *
- * The key field here is sbi->s_groups_count: as long as
- * that retains its old value, nobody is going to access the new
- * group.
- *
- * So first we update all the descriptor metadata for the new
- * group; then we update the total disk blocks count; then we
- * update the groups count to enable the group; then finally we
- * update the free space counts so that the system can start
- * using the new disk blocks.
- */
-
+ /*
+ * OK, now we've set up the new group. Time to make it active.
+ *
+ * Current kernels don't lock all allocations via lock_super(),
+ * so we have to be safe wrt. concurrent accesses the group
+ * data. So we need to be careful to set all of the relevant
+ * group descriptor data etc. *before* we enable the group.
+ *
+ * The key field here is sbi->s_groups_count: as long as
+ * that retains its old value, nobody is going to access the new
+ * group.
+ *
+ * So first we update all the descriptor metadata for the new
+ * group; then we update the total disk blocks count; then we
+ * update the groups count to enable the group; then finally we
+ * update the free space counts so that the system can start
+ * using the new disk blocks.
+ */
+
+ num_grp_locked = ext4_mb_get_buddy_cache_lock(sb, input->group);