monitor.c

   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 #include "mdadm.h"
  22 #include "mdmon.h"
  23 #include <sys/syscall.h>
  24 #include <sys/select.h>
  25 #include <signal.h>
  26
  27 static char *array_states[] = {
  28         "clear", "inactive", "suspended", "readonly", "read-auto",
  29         "clean", "active", "write-pending", "active-idle", NULL };
  30 static char *sync_actions[] = {
  31         "idle", "reshape", "resync", "recover", "check", "repair", NULL
  32 };
  33
  34 static int write_attr(char *attr, int fd)
  35 {
  36         return write(fd, attr, strlen(attr));
  37 }
  38
  39 static void add_fd(fd_set *fds, int *maxfd, int fd)
  40 {
  41         struct stat st;
  42         if (fd < 0)
  43                 return;
  44         if (fstat(fd, &st) == -1) {
  45                 dprintf("%s: Invalid fd %d\n", __func__, fd);
  46                 return;
  47         }
  48         if (st.st_nlink == 0) {
  49                 dprintf("%s: fd %d was deleted\n", __func__, fd);
  50                 return;
  51         }
  52         if (fd > *maxfd)
  53                 *maxfd = fd;
  54         FD_SET(fd, fds);
  55 }
  56
  57 static int read_attr(char *buf, int len, int fd)
  58 {
  59         int n;
  60
  61         if (fd < 0) {
  62                 buf[0] = 0;
  63                 return 0;
  64         }
  65         lseek(fd, 0, 0);
  66         n = read(fd, buf, len - 1);
  67
  68         if (n <= 0) {
  69                 buf[0] = 0;
  70                 return 0;
  71         }
  72         buf[n] = 0;
  73         if (buf[n-1] == '\n')
  74                 buf[n-1] = 0;
  75         return n;
  76 }
  77
  78 static unsigned long long read_resync_start(int fd)
  79 {
  80         char buf[30];
  81         int n;
  82
  83         n = read_attr(buf, 30, fd);
  84         if (n <= 0)
  85                 return 0;
  86         if (strncmp(buf, "none", 4) == 0)
  87                 return MaxSector;
  88         else
  89                 return strtoull(buf, NULL, 10);
  90 }
  91
  92 static unsigned long long read_sync_completed(int fd)
  93 {
  94         unsigned long long val;
  95         char buf[50];
  96         int n;
  97         char *ep;
  98
  99         n = read_attr(buf, 50, fd);
 100
 101         if (n <= 0)
 102                 return 0;
 103         buf[n] = 0;
 104         val = strtoull(buf, &ep, 0);
 105         if (ep == buf || (*ep != 0 && *ep != '\n' && *ep != ' '))
 106                 return 0;
 107         return val;
 108 }
 109
 110 static enum array_state read_state(int fd)
 111 {
 112         char buf[20];
 113         int n = read_attr(buf, 20, fd);
 114
 115         if (n <= 0)
 116                 return bad_word;
 117         return (enum array_state) sysfs_match_word(buf, array_states);
 118 }
 119
 120 static enum sync_action read_action( int fd)
 121 {
 122         char buf[20];
 123         int n = read_attr(buf, 20, fd);
 124
 125         if (n <= 0)
 126                 return bad_action;
 127         return (enum sync_action) sysfs_match_word(buf, sync_actions);
 128 }
 129
 130 int read_dev_state(int fd)
 131 {
 132         char buf[60];
 133         int n = read_attr(buf, 60, fd);
 134         char *cp;
 135         int rv = 0;
 136
 137         if (n <= 0)
 138                 return 0;
 139
 140         cp = buf;
 141         while (cp) {
 142                 if (sysfs_attr_match(cp, "faulty"))
 143                         rv |= DS_FAULTY;
 144                 if (sysfs_attr_match(cp, "in_sync"))
 145                         rv |= DS_INSYNC;
 146                 if (sysfs_attr_match(cp, "write_mostly"))
 147                         rv |= DS_WRITE_MOSTLY;
 148                 if (sysfs_attr_match(cp, "spare"))
 149                         rv |= DS_SPARE;
 150                 if (sysfs_attr_match(cp, "blocked"))
 151                         rv |= DS_BLOCKED;
 152                 cp = strchr(cp, ',');
 153                 if (cp)
 154                         cp++;
 155         }
 156         return rv;
 157 }
 158
 159 static void signal_manager(void)
 160 {
 161         /* tgkill(getpid(), mon_tid, SIGUSR1); */
 162         int pid = getpid();
 163         syscall(SYS_tgkill, pid, mgr_tid, SIGUSR1);
 164 }
 165
 166 /* Monitor a set of active md arrays - all of which share the
 167  * same metadata - and respond to events that require
 168  * metadata update.
 169  *
 170  * New arrays are detected by another thread which allocates
 171  * required memory and attaches the data structure to our list.
 172  *
 173  * Events:
 174  *  Array stops.
 175  *    This is detected by array_state going to 'clear' or 'inactive'.
 176  *    while we thought it was active.
 177  *    Response is to mark metadata as clean and 'clear' the array(??)
 178  *  write-pending
 179  *    array_state if 'write-pending'
 180  *    We mark metadata as 'dirty' then set array to 'active'.
 181  *  active_idle
 182  *    Either ignore, or mark clean, then mark metadata as clean.
 183  *
 184  *  device fails
 185  *    detected by rd-N/state reporting "faulty"
 186  *    mark device as 'failed' in metadata, let the kernel release the
 187  *    device by writing '-blocked' to rd/state, and finally write 'remove' to
 188  *    rd/state.  Before a disk can be replaced it must be failed and removed
 189  *    from all container members, this will be preemptive for the other
 190  *    arrays... safe?
 191  *
 192  *  sync completes
 193  *    sync_action was 'resync' and becomes 'idle' and resync_start becomes
 194  *    MaxSector
 195  *    Notify metadata that sync is complete.
 196  *
 197  *  recovery completes
 198  *    sync_action changes from 'recover' to 'idle'
 199  *    Check each device state and mark metadata if 'faulty' or 'in_sync'.
 200  *
 201  *  deal with resync
 202  *    This only happens on finding a new array... mdadm will have set
 203  *    'resync_start' to the correct value.  If 'resync_start' indicates that an
 204  *    resync needs to occur set the array to the 'active' state rather than the
 205  *    initial read-auto state.
 206  *
 207  *
 208  *
 209  * We wait for a change (poll/select) on array_state, sync_action, and
 210  * each rd-X/state file.
 211  * When we get any change, we check everything.  So read each state file,
 212  * then decide what to do.
 213  *
 214  * The core action is to write new metadata to all devices in the array.
 215  * This is done at most once on any wakeup.
 216  * After that we might:
 217  *   - update the array_state
 218  *   - set the role of some devices.
 219  *   - request a sync_action
 220  *
 221  */
 222
 223 #define ARRAY_DIRTY 1
 224 #define ARRAY_BUSY 2
 225 static int read_and_act(struct active_array *a)
 226 {
 227         unsigned long long sync_completed;
 228         int check_degraded = 0;
 229         int check_reshape = 0;
 230         int deactivate = 0;
 231         struct mdinfo *mdi;
 232         int ret = 0;
 233         int count = 0;
 234
 235         a->next_state = bad_word;
 236         a->next_action = bad_action;
 237
 238         a->curr_state = read_state(a->info.state_fd);
 239         a->curr_action = read_action(a->action_fd);
 240         a->info.resync_start = read_resync_start(a->resync_start_fd);
 241         sync_completed = read_sync_completed(a->sync_completed_fd);
 242         for (mdi = a->info.devs; mdi ; mdi = mdi->next) {
 243                 mdi->next_state = 0;
 244                 mdi->curr_state = 0;
 245                 if (mdi->state_fd >= 0) {
 246                         mdi->recovery_start = read_resync_start(mdi->recovery_fd);
 247                         mdi->curr_state = read_dev_state(mdi->state_fd);
 248                 }
 249         }
 250
 251         if (a->curr_state > inactive &&
 252             a->prev_state == inactive) {
 253                 /* array has been started
 254                  * possible that container operation has to be completed
 255                  */
 256                 a->container->ss->set_array_state(a, 0);
 257         }
 258         if (a->curr_state <= inactive &&
 259             a->prev_state > inactive) {
 260                 /* array has been stopped */
 261                 a->container->ss->set_array_state(a, 1);
 262                 a->next_state = clear;
 263                 deactivate = 1;
 264         }
 265         if (a->curr_state == write_pending) {
 266                 a->container->ss->set_array_state(a, 0);
 267                 a->next_state = active;
 268                 ret |= ARRAY_DIRTY;
 269         }
 270         if (a->curr_state == active_idle) {
 271                 /* Set array to 'clean' FIRST, then mark clean
 272                  * in the metadata
 273                  */
 274                 a->next_state = clean;
 275                 ret |= ARRAY_DIRTY;
 276         }
 277         if (a->curr_state == clean) {
 278                 a->container->ss->set_array_state(a, 1);
 279         }
 280         if (a->curr_state == active ||
 281             a->curr_state == suspended ||
 282             a->curr_state == bad_word)
 283                 ret |= ARRAY_DIRTY;
 284         if (a->curr_state == readonly) {
 285                 /* Well, I'm ready to handle things.  If readonly
 286                  * wasn't requested, transition to read-auto.
 287                  */
 288                 char buf[64];
 289                 read_attr(buf, sizeof(buf), a->metadata_fd);
 290                 if (strncmp(buf, "external:-", 10) == 0) {
 291                         /* explicit request for readonly array.  Leave it alone */
 292                         ;
 293                 } else {
 294                         if (a->container->ss->set_array_state(a, 2))
 295                                 a->next_state = read_auto; /* array is clean */
 296                         else {
 297                                 a->next_state = active; /* Now active for recovery etc */
 298                                 ret |= ARRAY_DIRTY;
 299                         }
 300                 }
 301         }
 302
 303         if (!deactivate &&
 304             a->curr_action == idle &&
 305             a->prev_action == resync) {
 306                 /* A resync has finished.  The endpoint is recorded in
 307                  * 'sync_start'.  We don't update the metadata
 308                  * until the array goes inactive or readonly though.
 309                  * Just check if we need to fiddle spares.
 310                  */
 311                 a->container->ss->set_array_state(a, a->curr_state <= clean);
 312                 check_degraded = 1;
 313         }
 314
 315         if (!deactivate &&
 316             a->curr_action == idle &&
 317             a->prev_action == recover) {
 318                 /* A recovery has finished.  Some disks may be in sync now,
 319                  * and the array may no longer be degraded
 320                  */
 321                 for (mdi = a->info.devs ; mdi ; mdi = mdi->next) {
 322                         a->container->ss->set_disk(a, mdi->disk.raid_disk,
 323                                                    mdi->curr_state);
 324                         if (! (mdi->curr_state & DS_INSYNC))
 325                                 check_degraded = 1;
 326                         count++;
 327                 }
 328                 if (count != a->info.array.raid_disks)
 329                         check_degraded = 1;
 330         }
 331
 332         if (!deactivate &&
 333             a->curr_action == reshape &&
 334             a->prev_action != reshape)
 335                 /* reshape was requested by mdadm.  Need to see if
 336                  * new devices have been added.  Manager does that
 337                  * when it sees check_reshape
 338                  */
 339                 check_reshape = 1;
 340
 341         /* Check for failures and if found:
 342          * 1/ Record the failure in the metadata and unblock the device.
 343          *    FIXME update the kernel to stop notifying on failed drives when
 344          *    the array is readonly and we have cleared 'blocked'
 345          * 2/ Try to remove the device if the array is writable, or can be
 346          *    made writable.
 347          */
 348         for (mdi = a->info.devs ; mdi ; mdi = mdi->next) {
 349                 if (mdi->curr_state & DS_FAULTY) {
 350                         a->container->ss->set_disk(a, mdi->disk.raid_disk,
 351                                                    mdi->curr_state);
 352                         check_degraded = 1;
 353                         if (mdi->curr_state & DS_BLOCKED)
 354                                 mdi->next_state |= DS_UNBLOCK;
 355                         if (a->curr_state == read_auto) {
 356                                 a->container->ss->set_array_state(a, 0);
 357                                 a->next_state = active;
 358                         }
 359                         if (a->curr_state > readonly)
 360                                 mdi->next_state |= DS_REMOVE;
 361                 }
 362         }
 363
 364         /* Check for recovery checkpoint notifications.  We need to be a
 365          * minimum distance away from the last checkpoint to prevent
 366          * over checkpointing.  Note reshape checkpointing is handled
 367          * in the second branch.
 368          */
 369         if (sync_completed > a->last_checkpoint &&
 370             sync_completed - a->last_checkpoint > a->info.component_size >> 4 &&
 371             a->curr_action > reshape) {
 372                 /* A (non-reshape) sync_action has reached a checkpoint.
 373                  * Record the updated position in the metadata
 374                  */
 375                 a->last_checkpoint = sync_completed;
 376                 a->container->ss->set_array_state(a, a->curr_state <= clean);
 377         } else if ((a->curr_action == idle && a->prev_action == reshape) ||
 378                    (a->curr_action == reshape
 379                     && sync_completed > a->last_checkpoint) ) {
 380                 /* Reshape has progressed or completed so we need to
 381                  * update the array state - and possibly the array size
 382                  */
 383                 if (sync_completed != 0)
 384                         a->last_checkpoint = sync_completed;
 385                 /* We might need to update last_checkpoint depending on
 386                  * the reason that reshape finished.
 387                  * if array reshape is really finished:
 388                  *        set check point to the end, this allows
 389                  *        set_array_state() to finalize reshape in metadata
 390                  * if reshape if broken: do not set checkpoint to the end
 391                  *        this allows for reshape restart from checkpoint
 392                  */
 393                 if ((a->curr_action != reshape) &&
 394                     (a->prev_action == reshape)) {
 395                         char buf[40];
 396                         if ((sysfs_get_str(&a->info, NULL,
 397                                           "reshape_position",
 398                                           buf,
 399                                           sizeof(buf)) >= 0) &&
 400                              strncmp(buf, "none", 4) == 0)
 401                                 a->last_checkpoint = a->info.component_size;
 402                 }
 403                 a->container->ss->set_array_state(a, a->curr_state <= clean);
 404                 a->last_checkpoint = sync_completed;
 405         }
 406
 407         if (sync_completed > a->last_checkpoint)
 408                 a->last_checkpoint = sync_completed;
 409
 410         a->container->ss->sync_metadata(a->container);
 411         dprintf("%s(%d): state:%s action:%s next(", __func__, a->info.container_member,
 412                 array_states[a->curr_state], sync_actions[a->curr_action]);
 413
 414         /* Effect state changes in the array */
 415         if (a->next_state != bad_word) {
 416                 dprintf(" state:%s", array_states[a->next_state]);
 417                 write_attr(array_states[a->next_state], a->info.state_fd);
 418         }
 419         if (a->next_action != bad_action) {
 420                 write_attr(sync_actions[a->next_action], a->action_fd);
 421                 dprintf(" action:%s", sync_actions[a->next_action]);
 422         }
 423         for (mdi = a->info.devs; mdi ; mdi = mdi->next) {
 424                 if (mdi->next_state & DS_UNBLOCK) {
 425                         dprintf(" %d:-blocked", mdi->disk.raid_disk);
 426                         write_attr("-blocked", mdi->state_fd);
 427                 }
 428
 429                 if ((mdi->next_state & DS_REMOVE) && mdi->state_fd >= 0) {
 430                         int remove_result;
 431
 432                         /* The kernel may not be able to immediately remove the
 433                          * disk.  In that case we wait a little while and
 434                          * try again.
 435                          */
 436                         remove_result = write_attr("remove", mdi->state_fd);
 437                         if (remove_result > 0) {
 438                                 dprintf(" %d:removed", mdi->disk.raid_disk);
 439                                 close(mdi->state_fd);
 440                                 close(mdi->recovery_fd);
 441                                 mdi->state_fd = -1;
 442                         } else
 443                                 ret |= ARRAY_BUSY;
 444                 }
 445                 if (mdi->next_state & DS_INSYNC) {
 446                         write_attr("+in_sync", mdi->state_fd);
 447                         dprintf(" %d:+in_sync", mdi->disk.raid_disk);
 448                 }
 449         }
 450         dprintf(" )\n");
 451
 452         /* move curr_ to prev_ */
 453         a->prev_state = a->curr_state;
 454
 455         a->prev_action = a->curr_action;
 456
 457         for (mdi = a->info.devs; mdi ; mdi = mdi->next) {
 458                 mdi->prev_state = mdi->curr_state;
 459                 mdi->next_state = 0;
 460         }
 461
 462         if (check_degraded || check_reshape) {
 463                 /* manager will do the actual check */
 464                 if (check_degraded)
 465                         a->check_degraded = 1;
 466                 if (check_reshape)
 467                         a->check_reshape = 1;
 468                 signal_manager();
 469         }
 470
 471         if (deactivate)
 472                 a->container = NULL;
 473
 474         return ret;
 475 }
 476
 477 static struct mdinfo *
 478 find_device(struct active_array *a, int major, int minor)
 479 {
 480         struct mdinfo *mdi;
 481
 482         for (mdi = a->info.devs ; mdi ; mdi = mdi->next)
 483                 if (mdi->disk.major == major && mdi->disk.minor == minor)
 484                         return mdi;
 485
 486         return NULL;
 487 }
 488
 489 static void reconcile_failed(struct active_array *aa, struct mdinfo *failed)
 490 {
 491         struct active_array *a;
 492         struct mdinfo *victim;
 493
 494         for (a = aa; a; a = a->next) {
 495                 if (!a->container || a->to_remove)
 496                         continue;
 497                 victim = find_device(a, failed->disk.major, failed->disk.minor);
 498                 if (!victim)
 499                         continue;
 500
 501                 if (!(victim->curr_state & DS_FAULTY))
 502                         write_attr("faulty", victim->state_fd);
 503         }
 504 }
 505
 506 #ifdef DEBUG
 507 static void dprint_wake_reasons(fd_set *fds)
 508 {
 509         int i;
 510         char proc_path[256];
 511         char link[256];
 512         char *basename;
 513         int rv;
 514
 515         fprintf(stderr, "monitor: wake ( ");
 516         for (i = 0; i < FD_SETSIZE; i++) {
 517                 if (FD_ISSET(i, fds)) {
 518                         sprintf(proc_path, "/proc/%d/fd/%d",
 519                                 (int) getpid(), i);
 520
 521                         rv = readlink(proc_path, link, sizeof(link) - 1);
 522                         if (rv < 0) {
 523                                 fprintf(stderr, "%d:unknown ", i);
 524                                 continue;
 525                         }
 526                         link[rv] = '\0';
 527                         basename = strrchr(link, '/');
 528                         fprintf(stderr, "%d:%s ",
 529                                 i, basename ? ++basename : link);
 530                 }
 531         }
 532         fprintf(stderr, ")\n");
 533 }
 534 #endif
 535
 536 int monitor_loop_cnt;
 537
 538 static int wait_and_act(struct supertype *container, int nowait)
 539 {
 540         fd_set rfds;
 541         int maxfd = 0;
 542         struct active_array **aap = &container->arrays;
 543         struct active_array *a, **ap;
 544         int rv;
 545         struct mdinfo *mdi;
 546         static unsigned int dirty_arrays = ~0; /* start at some non-zero value */
 547
 548         FD_ZERO(&rfds);
 549
 550         for (ap = aap ; *ap ;) {
 551                 a = *ap;
 552                 /* once an array has been deactivated we want to
 553                  * ask the manager to discard it.
 554                  */
 555                 if (!a->container || a->to_remove) {
 556                         if (discard_this) {
 557                                 ap = &(*ap)->next;
 558                                 continue;
 559                         }
 560                         *ap = a->next;
 561                         a->next = NULL;
 562                         discard_this = a;
 563                         signal_manager();
 564                         continue;
 565                 }
 566
 567                 add_fd(&rfds, &maxfd, a->info.state_fd);
 568                 add_fd(&rfds, &maxfd, a->action_fd);
 569                 add_fd(&rfds, &maxfd, a->sync_completed_fd);
 570                 for (mdi = a->info.devs ; mdi ; mdi = mdi->next)
 571                         add_fd(&rfds, &maxfd, mdi->state_fd);
 572
 573                 ap = &(*ap)->next;
 574         }
 575
 576         if (manager_ready && (*aap == NULL || (sigterm && !dirty_arrays))) {
 577                 /* No interesting arrays, or we have been told to
 578                  * terminate and everything is clean.  Lets see about
 579                  * exiting.  Note that blocking at this point is not a
 580                  * problem as there are no active arrays, there is
 581                  * nothing that we need to be ready to do.
 582                  */
 583                 int fd;
 584                 if (sigterm)
 585                         fd = open_dev_excl(container->devnm);
 586                 else
 587                         fd = open_dev_flags(container->devnm, O_RDONLY|O_EXCL);
 588                 if (fd >= 0 || errno != EBUSY) {
 589                         /* OK, we are safe to leave */
 590                         if (sigterm && !dirty_arrays)
 591                                 dprintf("caught sigterm, all clean... exiting\n");
 592                         else
 593                                 dprintf("no arrays to monitor... exiting\n");
 594                         if (!sigterm)
 595                                 /* On SIGTERM, someone (the take-over mdmon) will
 596                                  * clean up
 597                                  */
 598                                 remove_pidfile(container->devnm);
 599                         exit_now = 1;
 600                         signal_manager();
 601                         close(fd);
 602                         exit(0);
 603                 }
 604         }
 605
 606         if (!nowait) {
 607                 sigset_t set;
 608                 struct timespec ts;
 609                 ts.tv_sec = 24*3600;
 610                 ts.tv_nsec = 0;
 611                 if (*aap == NULL || container->retry_soon) {
 612                         /* just waiting to get O_EXCL access */
 613                         ts.tv_sec = 0;
 614                         ts.tv_nsec = 20000000ULL;
 615                 }
 616                 sigprocmask(SIG_UNBLOCK, NULL, &set);
 617                 sigdelset(&set, SIGUSR1);
 618                 monitor_loop_cnt |= 1;
 619                 rv = pselect(maxfd+1, NULL, NULL, &rfds, &ts, &set);
 620                 monitor_loop_cnt += 1;
 621                 if (rv == -1 && errno == EINTR)
 622                         rv = 0;
 623                 #ifdef DEBUG
 624                 dprint_wake_reasons(&rfds);
 625                 #endif
 626                 container->retry_soon = 0;
 627         }
 628
 629         if (update_queue) {
 630                 struct metadata_update *this;
 631
 632                 for (this = update_queue; this ; this = this->next)
 633                         container->ss->process_update(container, this);
 634
 635                 update_queue_handled = update_queue;
 636                 update_queue = NULL;
 637                 signal_manager();
 638                 container->ss->sync_metadata(container);
 639         }
 640
 641         rv = 0;
 642         dirty_arrays = 0;
 643         for (a = *aap; a ; a = a->next) {
 644
 645                 if (a->replaces && !discard_this) {
 646                         struct active_array **ap;
 647                         for (ap = &a->next; *ap && *ap != a->replaces;
 648                              ap = & (*ap)->next)
 649                                 ;
 650                         if (*ap)
 651                                 *ap = (*ap)->next;
 652                         discard_this = a->replaces;
 653                         a->replaces = NULL;
 654                         /* FIXME check if device->state_fd need to be cleared?*/
 655                         signal_manager();
 656                 }
 657                 if (a->container && !a->to_remove) {
 658                         int ret = read_and_act(a);
 659                         rv |= 1;
 660                         dirty_arrays += !!(ret & ARRAY_DIRTY);
 661                         /* when terminating stop manipulating the array after it
 662                          * is clean, but make sure read_and_act() is given a
 663                          * chance to handle 'active_idle'
 664                          */
 665                         if (sigterm && !(ret & ARRAY_DIRTY))
 666                                 a->container = NULL; /* stop touching this array */
 667                         if (ret & ARRAY_BUSY)
 668                                 container->retry_soon = 1;
 669                 }
 670         }
 671
 672         /* propagate failures across container members */
 673         for (a = *aap; a ; a = a->next) {
 674                 if (!a->container || a->to_remove)
 675                         continue;
 676                 for (mdi = a->info.devs ; mdi ; mdi = mdi->next)
 677                         if (mdi->curr_state & DS_FAULTY)
 678                                 reconcile_failed(*aap, mdi);
 679         }
 680
 681         return rv;
 682 }
 683
 684 void do_monitor(struct supertype *container)
 685 {
 686         int rv;
 687         int first = 1;
 688         do {
 689                 rv = wait_and_act(container, first);
 690                 first = 0;
 691         } while (rv >= 0);
 692 }