10592 misc. metaslab and vdev related ZoL bug fixes
Portions contributed by: Jerry Jelinek <jerry.jelinek@joyent.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed by: Giuseppe Di Natale <guss80@gmail.com>
Reviewed by: George Melikov <mail@gmelikov.ru>
Reviewed by: Paul Dagnelie <pcd@delphix.com>
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed by: Tony Hutter <hutter2@llnl.gov>
Reviewed by: Kody Kantor <kody.kantor@joyent.com>
Approved by: Dan McDonald <danmcd@joyent.com>

*** 50,59 ****
--- 50,61 ----
  void metaslab_fini(metaslab_t *);
  
  int metaslab_load(metaslab_t *);
  void metaslab_unload(metaslab_t *);
  
+ uint64_t metaslab_allocated_space(metaslab_t *);
+ 
  void metaslab_sync(metaslab_t *, uint64_t);
  void metaslab_sync_done(metaslab_t *, uint64_t);
  void metaslab_sync_reassess(metaslab_group_t *);
  uint64_t metaslab_block_maxsize(metaslab_t *);
  
*** 113,122 ****
--- 115,125 ----
  uint64_t metaslab_group_fragmentation(metaslab_group_t *);
  void metaslab_group_histogram_remove(metaslab_group_t *, metaslab_t *);
  void metaslab_group_alloc_decrement(spa_t *, uint64_t, void *, int, int,
      boolean_t);
  void metaslab_group_alloc_verify(spa_t *, const blkptr_t *, void *, int);
+ void metaslab_recalculate_weight_and_sort(metaslab_t *);
  
  #ifdef  __cplusplus
  }
  #endif