mdmon.h

   1 /*
   2  * mdmon - monitor external metadata arrays
   3  *
   4  * Copyright (C) 2007-2009 Neil Brown <neilb@suse.de>
   5  * Copyright (C) 2007-2009 Intel Corporation
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms and conditions of the GNU General Public License,
   9  * version 2, as published by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  14  * more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along with
  17  * this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  19  */
  20
  21 extern const char Name[];
  22
  23 enum array_state { clear, inactive, suspended, readonly, read_auto,
  24                    clean, active, write_pending, active_idle, bad_word};
  25
  26 enum sync_action { idle, reshape, resync, recover, check, repair, bad_action };
  27
  28 struct active_array {
  29         struct mdinfo info;
  30         struct supertype *container;
  31         struct active_array *next, *replaces;
  32         int to_remove;
  33
  34         int action_fd;
  35         int resync_start_fd;
  36         int metadata_fd; /* for monitoring rw/ro status */
  37         int sync_completed_fd; /* for checkpoint notification events */
  38         unsigned long long last_checkpoint; /* sync_completed fires for many
  39                                              * reasons this field makes sure the
  40                                              * kernel has made progress before
  41                                              * moving the checkpoint.  It is
  42                                              * cleared by the metadata handler
  43                                              * when it determines recovery is
  44                                              * terminated.
  45                                              */
  46
  47         enum array_state prev_state, curr_state, next_state;
  48         enum sync_action prev_action, curr_action, next_action;
  49
  50         int check_degraded; /* flag set by mon, read by manage */
  51         int check_reshape; /* flag set by mon, read by manage */
  52 };
  53
  54 /*
  55  * Metadata updates are handled by the monitor thread,
  56  * as it has exclusive access to the metadata.
  57  * When the manager want to updates metadata, either
  58  * for it's own reason (e.g. committing a spare) or
  59  * on behalf of mdadm, it creates a metadata_update
  60  * structure and queues it to the monitor.
  61  * Updates are created and processed by code under the
  62  * superswitch.  All common code sees them as opaque
  63  * blobs.
  64  */
  65 extern struct metadata_update *update_queue, *update_queue_handled;
  66
  67 #define MD_MAJOR 9
  68
  69 extern struct active_array *container;
  70 extern struct active_array *discard_this;
  71 extern struct active_array *pending_discard;
  72 extern struct md_generic_cmd *active_cmd;
  73
  74 void remove_pidfile(char *devname);
  75 void do_monitor(struct supertype *container);
  76 void do_manager(struct supertype *container);
  77 extern int sigterm;
  78
  79 int read_dev_state(int fd);
  80 int is_container_member(struct mdstat_ent *mdstat, char *container);
  81
  82 struct mdstat_ent *mdstat_read(int hold, int start);
  83
  84 extern int exit_now, manager_ready;
  85 extern int mon_tid, mgr_tid;
  86 extern int monitor_loop_cnt;
  87
  88 /* helper routine to determine resync completion since MaxSector is a
  89  * moving target
  90  */
  91 static inline int is_resync_complete(struct mdinfo *array)
  92 {
  93         unsigned long long sync_size = 0;
  94         int ncopies, l;
  95         switch(array->array.level) {
  96         case 1:
  97         case 4:
  98         case 5:
  99         case 6:
 100                 sync_size = array->component_size;
 101                 break;
 102         case 10:
 103                 l = array->array.layout;
 104                 ncopies = (l & 0xff) * ((l >> 8) && 0xff);
 105                 sync_size = array->component_size * array->array.raid_disks;
 106                 sync_size /= ncopies;
 107                 break;
 108         }
 109         return array->resync_start >= sync_size;
 110 }