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("Invalid fd %d\n", fd);
  46                 return;
  47         }
  48         if (st.st_nlink == 0) {
  49                 dprintf("fd %d was deleted\n", 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 void read_resync_start(int fd, unsigned long long *v)
  79 {
  80         char buf[30];
  81         int n;
  82
  83         n = read_attr(buf, 30, fd);
  84         if (n <= 0) {
  85                 dprintf("Failed to read resync_start (%d)\n", fd);
  86                 return;
  87         }
  88         if (strncmp(buf, "none", 4) == 0)
  89                 *v = MaxSector;
  90         else
  91                 *v = strtoull(buf, NULL, 10);
  92 }
  93
  94 static unsigned long long read_sync_completed(int fd)
  95 {
  96         unsigned long long val;
  97         char buf[50];
  98         int n;
  99         char *ep;
 100
 101         n = read_attr(buf, 50, fd);
 102
 103         if (n <= 0)
 104                 return 0;
 105         buf[n] = 0;
 106         val = strtoull(buf, &ep, 0);
 107         if (ep == buf || (*ep != 0 && *ep != '\n' && *ep != ' '))
 108                 return 0;
 109         return val;
 110 }
 111
 112 static enum array_state read_state(int fd)
 113 {
 114         char buf[20];
 115         int n = read_attr(buf, 20, fd);
 116
 117         if (n <= 0)
 118                 return bad_word;
 119         return (enum array_state) sysfs_match_word(buf, array_states);
 120 }
 121
 122 static enum sync_action read_action( int fd)
 123 {
 124         char buf[20];
 125         int n = read_attr(buf, 20, fd);
 126
 127         if (n <= 0)
 128                 return bad_action;
 129         return (enum sync_action) sysfs_match_word(buf, sync_actions);
 130 }
 131
 132 int read_dev_state(int fd)
 133 {
 134         char buf[100];
 135         int n = read_attr(buf, sizeof(buf), fd);
 136         char *cp;
 137         int rv = 0;
 138
 139         if (n <= 0)
 140                 return 0;
 141
 142         cp = buf;
 143         while (cp) {
 144                 if (sysfs_attr_match(cp, "faulty"))
 145                         rv |= DS_FAULTY;
 146                 if (sysfs_attr_match(cp, "in_sync"))
 147                         rv |= DS_INSYNC;
 148                 if (sysfs_attr_match(cp, "write_mostly"))
 149                         rv |= DS_WRITE_MOSTLY;
 150                 if (sysfs_attr_match(cp, "spare"))
 151                         rv |= DS_SPARE;
 152                 if (sysfs_attr_match(cp, "blocked"))
 153                         rv |= DS_BLOCKED;
 154                 cp = strchr(cp, ',');
 155                 if (cp)
 156                         cp++;
 157         }
 158         return rv;
 159 }
 160
 161 static void signal_manager(void)
 162 {
 163         /* tgkill(getpid(), mon_tid, SIGUSR1); */
 164         int pid = getpid();
 165         syscall(SYS_tgkill, pid, mgr_tid, SIGUSR1);
 166 }
 167
 168 /* Monitor a set of active md arrays - all of which share the
 169  * same metadata - and respond to events that require
 170  * metadata update.
 171  *
 172  * New arrays are detected by another thread which allocates
 173  * required memory and attaches the data structure to our list.
 174  *
 175  * Events:
 176  *  Array stops.
 177  *    This is detected by array_state going to 'clear' or 'inactive'.
 178  *    while we thought it was active.
 179  *    Response is to mark metadata as clean and 'clear' the array(??)
 180  *  write-pending
 181  *    array_state if 'write-pending'
 182  *    We mark metadata as 'dirty' then set array to 'active'.
 183  *  active_idle
 184  *    Either ignore, or mark clean, then mark metadata as clean.
 185  *
 186  *  device fails
 187  *    detected by rd-N/state reporting "faulty"
 188  *    mark device as 'failed' in metadata, let the kernel release the
 189  *    device by writing '-blocked' to rd/state, and finally write 'remove' to
 190  *    rd/state.  Before a disk can be replaced it must be failed and removed
 191  *    from all container members, this will be preemptive for the other
 192  *    arrays... safe?
 193  *
 194  *  sync completes
 195  *    sync_action was 'resync' and becomes 'idle' and resync_start becomes
 196  *    MaxSector
 197  *    Notify metadata that sync is complete.
 198  *
 199  *  recovery completes
 200  *    sync_action changes from 'recover' to 'idle'
 201  *    Check each device state and mark metadata if 'faulty' or 'in_sync'.
 202  *
 203  *  deal with resync
 204  *    This only happens on finding a new array... mdadm will have set
 205  *    'resync_start' to the correct value.  If 'resync_start' indicates that an
 206  *    resync needs to occur set the array to the 'active' state rather than the
 207  *    initial read-auto state.
 208  *
 209  *
 210  *
 211  * We wait for a change (poll/select) on array_state, sync_action, and
 212  * each rd-X/state file.
 213  * When we get any change, we check everything.  So read each state file,
 214  * then decide what to do.
 215  *
 216  * The core action is to write new metadata to all devices in the array.
 217  * This is done at most once on any wakeup.
 218  * After that we might:
 219  *   - update the array_state
 220  *   - set the role of some devices.
 221  *   - request a sync_action
 222  *
 223  */
 224
 225 #define ARRAY_DIRTY 1
 226 #define ARRAY_BUSY 2
 227 static int read_and_act(struct active_array *a)
 228 {
 229         unsigned long long sync_completed;
 230         int check_degraded = 0;
 231         int check_reshape = 0;
 232         int deactivate = 0;
 233         struct mdinfo *mdi;
 234         int ret = 0;
 235         int count = 0;
 236         struct timeval tv;
 237
 238         a->next_state = bad_word;
 239         a->next_action = bad_action;
 240
 241         a->curr_state = read_state(a->info.state_fd);
 242         a->curr_action = read_action(a->action_fd);
 243         if (a->curr_state != clear)
 244                 /*
 245                  * In "clear" state, resync_start may wrongly be set to "0"
 246                  * when the kernel called md_clean but didn't remove the
 247                  * sysfs attributes yet
 248                  */
 249                 read_resync_start(a->resync_start_fd, &a->info.resync_start);
 250         sync_completed = read_sync_completed(a->sync_completed_fd);
 251         for (mdi = a->info.devs; mdi ; mdi = mdi->next) {
 252                 mdi->next_state = 0;
 253                 mdi->curr_state = 0;
 254                 if (mdi->state_fd >= 0) {
 255                         read_resync_start(mdi->recovery_fd,
 256                                           &mdi->recovery_start);
 257                         mdi->curr_state = read_dev_state(mdi->state_fd);
 258                 }
 259         }
 260
 261         gettimeofday(&tv, NULL);
 262         dprintf("(%d): %ld.%06ld state:%s prev:%s action:%s prev: %s start:%llu\n",
 263                 a->info.container_member,
 264                 tv.tv_sec, tv.tv_usec,
 265                 array_states[a->curr_state],
 266                 array_states[a->prev_state],
 267                 sync_actions[a->curr_action],
 268                 sync_actions[a->prev_action],
 269                 a->info.resync_start
 270                 );
 271
 272         if ((a->curr_state == bad_word || a->curr_state <= inactive) &&
 273             a->prev_state > inactive) {
 274                 /* array has been stopped */
 275                 a->container->ss->set_array_state(a, 1);
 276                 a->next_state = clear;
 277                 deactivate = 1;
 278         }
 279         if (a->curr_state == write_pending) {
 280                 a->container->ss->set_array_state(a, 0);
 281                 a->next_state = active;
 282                 ret |= ARRAY_DIRTY;
 283         }
 284         if (a->curr_state == active_idle) {
 285                 /* Set array to 'clean' FIRST, then mark clean
 286                  * in the metadata
 287                  */
 288                 a->next_state = clean;
 289                 ret |= ARRAY_DIRTY;
 290         }
 291         if (a->curr_state == clean) {
 292                 a->container->ss->set_array_state(a, 1);
 293         }
 294         if (a->curr_state == active ||
 295             a->curr_state == suspended)
 296                 ret |= ARRAY_DIRTY;
 297         if (a->curr_state == readonly) {
 298                 /* Well, I'm ready to handle things.  If readonly
 299                  * wasn't requested, transition to read-auto.
 300                  */
 301                 char buf[64];
 302                 read_attr(buf, sizeof(buf), a->metadata_fd);
 303                 if (strncmp(buf, "external:-", 10) == 0) {
 304                         /* explicit request for readonly array.  Leave it alone */
 305                         ;
 306                 } else {
 307                         if (a->container->ss->set_array_state(a, 2))
 308                                 a->next_state = read_auto; /* array is clean */
 309                         else {
 310                                 a->next_state = active; /* Now active for recovery etc */
 311                                 ret |= ARRAY_DIRTY;
 312                         }
 313                 }
 314         }
 315
 316         if (!deactivate &&
 317             a->curr_action == idle &&
 318             a->prev_action == resync) {
 319                 /* A resync has finished.  The endpoint is recorded in
 320                  * 'sync_start'.  We don't update the metadata
 321                  * until the array goes inactive or readonly though.
 322                  * Just check if we need to fiddle spares.
 323                  */
 324                 a->container->ss->set_array_state(a, a->curr_state <= clean);
 325                 check_degraded = 1;
 326         }
 327
 328         if (!deactivate &&
 329             a->curr_action == idle &&
 330             a->prev_action == recover) {
 331                 /* A recovery has finished.  Some disks may be in sync now,
 332                  * and the array may no longer be degraded
 333                  */
 334                 for (mdi = a->info.devs ; mdi ; mdi = mdi->next) {
 335                         a->container->ss->set_disk(a, mdi->disk.raid_disk,
 336                                                    mdi->curr_state);
 337                         if (! (mdi->curr_state & DS_INSYNC))
 338                                 check_degraded = 1;
 339                         count++;
 340                 }
 341                 if (count != a->info.array.raid_disks)
 342                         check_degraded = 1;
 343         }
 344
 345         if (!deactivate &&
 346             a->curr_action == reshape &&
 347             a->prev_action != reshape)
 348                 /* reshape was requested by mdadm.  Need to see if
 349                  * new devices have been added.  Manager does that
 350                  * when it sees check_reshape
 351                  */
 352                 check_reshape = 1;
 353
 354         /* Check for failures and if found:
 355          * 1/ Record the failure in the metadata and unblock the device.
 356          *    FIXME update the kernel to stop notifying on failed drives when
 357          *    the array is readonly and we have cleared 'blocked'
 358          * 2/ Try to remove the device if the array is writable, or can be
 359          *    made writable.
 360          */
 361         for (mdi = a->info.devs ; mdi ; mdi = mdi->next) {
 362                 if (mdi->curr_state & DS_FAULTY) {
 363                         a->container->ss->set_disk(a, mdi->disk.raid_disk,
 364                                                    mdi->curr_state);
 365                         check_degraded = 1;
 366                         if (mdi->curr_state & DS_BLOCKED)
 367                                 mdi->next_state |= DS_UNBLOCK;
 368                         if (a->curr_state == read_auto) {
 369                                 a->container->ss->set_array_state(a, 0);
 370                                 a->next_state = active;
 371                         }
 372                         if (a->curr_state > readonly)
 373                                 mdi->next_state |= DS_REMOVE;
 374                 }
 375         }
 376
 377         /* Check for recovery checkpoint notifications.  We need to be a
 378          * minimum distance away from the last checkpoint to prevent
 379          * over checkpointing.  Note reshape checkpointing is handled
 380          * in the second branch.
 381          */
 382         if (sync_completed > a->last_checkpoint &&
 383             sync_completed - a->last_checkpoint > a->info.component_size >> 4 &&
 384             a->curr_action > reshape) {
 385                 /* A (non-reshape) sync_action has reached a checkpoint.
 386                  * Record the updated position in the metadata
 387                  */
 388                 a->last_checkpoint = sync_completed;
 389                 a->container->ss->set_array_state(a, a->curr_state <= clean);
 390         } else if ((a->curr_action == idle && a->prev_action == reshape) ||
 391                    (a->curr_action == reshape
 392                     && sync_completed > a->last_checkpoint) ) {
 393                 /* Reshape has progressed or completed so we need to
 394                  * update the array state - and possibly the array size
 395                  */
 396                 if (sync_completed != 0)
 397                         a->last_checkpoint = sync_completed;
 398                 /* We might need to update last_checkpoint depending on
 399                  * the reason that reshape finished.
 400                  * if array reshape is really finished:
 401                  *        set check point to the end, this allows
 402                  *        set_array_state() to finalize reshape in metadata
 403                  * if reshape if broken: do not set checkpoint to the end
 404                  *        this allows for reshape restart from checkpoint
 405                  */
 406                 if ((a->curr_action != reshape) &&
 407                     (a->prev_action == reshape)) {
 408                         char buf[40];
 409                         if ((sysfs_get_str(&a->info, NULL,
 410                                           "reshape_position",
 411                                           buf,
 412                                           sizeof(buf)) >= 0) &&
 413                              strncmp(buf, "none", 4) == 0)
 414                                 a->last_checkpoint = a->info.component_size;
 415                 }
 416                 a->container->ss->set_array_state(a, a->curr_state <= clean);
 417                 a->last_checkpoint = sync_completed;
 418         }
 419
 420         if (sync_completed > a->last_checkpoint)
 421                 a->last_checkpoint = sync_completed;
 422
 423         if (sync_completed >= a->info.component_size)
 424                 a->last_checkpoint = 0;
 425
 426         a->container->ss->sync_metadata(a->container);
 427         dprintf("(%d): state:%s action:%s next(", a->info.container_member,
 428                 array_states[a->curr_state], sync_actions[a->curr_action]);
 429
 430         /* Effect state changes in the array */
 431         if (a->next_state != bad_word) {
 432                 dprintf_cont(" state:%s", array_states[a->next_state]);
 433                 write_attr(array_states[a->next_state], a->info.state_fd);
 434         }
 435         if (a->next_action != bad_action) {
 436                 write_attr(sync_actions[a->next_action], a->action_fd);
 437                 dprintf_cont(" action:%s", sync_actions[a->next_action]);
 438         }
 439         for (mdi = a->info.devs; mdi ; mdi = mdi->next) {
 440                 if (mdi->next_state & DS_UNBLOCK) {
 441                         dprintf_cont(" %d:-blocked", mdi->disk.raid_disk);
 442                         write_attr("-blocked", mdi->state_fd);
 443                 }
 444
 445                 if ((mdi->next_state & DS_REMOVE) && mdi->state_fd >= 0) {
 446                         int remove_result;
 447
 448                         /* The kernel may not be able to immediately remove the
 449                          * disk.  In that case we wait a little while and
 450                          * try again.
 451                          */
 452                         remove_result = write_attr("remove", mdi->state_fd);
 453                         if (remove_result > 0) {
 454                                 dprintf_cont(" %d:removed", mdi->disk.raid_disk);
 455                                 close(mdi->state_fd);
 456                                 close(mdi->recovery_fd);
 457                                 close(mdi->bb_fd);
 458                                 close(mdi->ubb_fd);
 459                                 mdi->state_fd = -1;
 460                         } else
 461                                 ret |= ARRAY_BUSY;
 462                 }
 463                 if (mdi->next_state & DS_INSYNC) {
 464                         write_attr("+in_sync", mdi->state_fd);
 465                         dprintf_cont(" %d:+in_sync", mdi->disk.raid_disk);
 466                 }
 467         }
 468         dprintf_cont(" )\n");
 469
 470         /* move curr_ to prev_ */
 471         a->prev_state = a->curr_state;
 472
 473         a->prev_action = a->curr_action;
 474
 475         for (mdi = a->info.devs; mdi ; mdi = mdi->next) {
 476                 mdi->prev_state = mdi->curr_state;
 477                 mdi->next_state = 0;
 478         }
 479
 480         if (check_degraded || check_reshape) {
 481                 /* manager will do the actual check */
 482                 if (check_degraded)
 483                         a->check_degraded = 1;
 484                 if (check_reshape)
 485                         a->check_reshape = 1;
 486                 signal_manager();
 487         }
 488
 489         if (deactivate)
 490                 a->container = NULL;
 491
 492         return ret;
 493 }
 494
 495 static struct mdinfo *
 496 find_device(struct active_array *a, int major, int minor)
 497 {
 498         struct mdinfo *mdi;
 499
 500         for (mdi = a->info.devs ; mdi ; mdi = mdi->next)
 501                 if (mdi->disk.major == major && mdi->disk.minor == minor)
 502                         return mdi;
 503
 504         return NULL;
 505 }
 506
 507 static void reconcile_failed(struct active_array *aa, struct mdinfo *failed)
 508 {
 509         struct active_array *a;
 510         struct mdinfo *victim;
 511
 512         for (a = aa; a; a = a->next) {
 513                 if (!a->container || a->to_remove)
 514                         continue;
 515                 victim = find_device(a, failed->disk.major, failed->disk.minor);
 516                 if (!victim)
 517                         continue;
 518
 519                 if (!(victim->curr_state & DS_FAULTY))
 520                         write_attr("faulty", victim->state_fd);
 521         }
 522 }
 523
 524 #ifdef DEBUG
 525 static void dprint_wake_reasons(fd_set *fds)
 526 {
 527         int i;
 528         char proc_path[256];
 529         char link[256];
 530         char *basename;
 531         int rv;
 532
 533         fprintf(stderr, "monitor: wake ( ");
 534         for (i = 0; i < FD_SETSIZE; i++) {
 535                 if (FD_ISSET(i, fds)) {
 536                         sprintf(proc_path, "/proc/%d/fd/%d",
 537                                 (int) getpid(), i);
 538
 539                         rv = readlink(proc_path, link, sizeof(link) - 1);
 540                         if (rv < 0) {
 541                                 fprintf(stderr, "%d:unknown ", i);
 542                                 continue;
 543                         }
 544                         link[rv] = '\0';
 545                         basename = strrchr(link, '/');
 546                         fprintf(stderr, "%d:%s ",
 547                                 i, basename ? ++basename : link);
 548                 }
 549         }
 550         fprintf(stderr, ")\n");
 551 }
 552 #endif
 553
 554 int monitor_loop_cnt;
 555
 556 static int wait_and_act(struct supertype *container, int nowait)
 557 {
 558         fd_set rfds;
 559         int maxfd = 0;
 560         struct active_array **aap = &container->arrays;
 561         struct active_array *a, **ap;
 562         int rv;
 563         struct mdinfo *mdi;
 564         static unsigned int dirty_arrays = ~0; /* start at some non-zero value */
 565
 566         FD_ZERO(&rfds);
 567
 568         for (ap = aap ; *ap ;) {
 569                 a = *ap;
 570                 /* once an array has been deactivated we want to
 571                  * ask the manager to discard it.
 572                  */
 573                 if (!a->container || a->to_remove) {
 574                         if (discard_this) {
 575                                 ap = &(*ap)->next;
 576                                 continue;
 577                         }
 578                         *ap = a->next;
 579                         a->next = NULL;
 580                         discard_this = a;
 581                         signal_manager();
 582                         continue;
 583                 }
 584
 585                 add_fd(&rfds, &maxfd, a->info.state_fd);
 586                 add_fd(&rfds, &maxfd, a->action_fd);
 587                 add_fd(&rfds, &maxfd, a->sync_completed_fd);
 588                 for (mdi = a->info.devs ; mdi ; mdi = mdi->next) {
 589                         add_fd(&rfds, &maxfd, mdi->state_fd);
 590                         add_fd(&rfds, &maxfd, mdi->bb_fd);
 591                         add_fd(&rfds, &maxfd, mdi->ubb_fd);
 592                 }
 593
 594                 ap = &(*ap)->next;
 595         }
 596
 597         if (manager_ready && (*aap == NULL || (sigterm && !dirty_arrays))) {
 598                 /* No interesting arrays, or we have been told to
 599                  * terminate and everything is clean.  Lets see about
 600                  * exiting.  Note that blocking at this point is not a
 601                  * problem as there are no active arrays, there is
 602                  * nothing that we need to be ready to do.
 603                  */
 604                 int fd;
 605                 if (sigterm)
 606                         fd = open_dev_excl(container->devnm);
 607                 else
 608                         fd = open_dev_flags(container->devnm, O_RDONLY|O_EXCL);
 609                 if (fd >= 0 || errno != EBUSY) {
 610                         /* OK, we are safe to leave */
 611                         if (sigterm && !dirty_arrays)
 612                                 dprintf("caught sigterm, all clean... exiting\n");
 613                         else
 614                                 dprintf("no arrays to monitor... exiting\n");
 615                         if (!sigterm)
 616                                 /* On SIGTERM, someone (the take-over mdmon) will
 617                                  * clean up
 618                                  */
 619                                 remove_pidfile(container->devnm);
 620                         exit_now = 1;
 621                         signal_manager();
 622                         close(fd);
 623                         exit(0);
 624                 }
 625         }
 626
 627         if (!nowait) {
 628                 sigset_t set;
 629                 struct timespec ts;
 630                 ts.tv_sec = 24*3600;
 631                 ts.tv_nsec = 0;
 632                 if (*aap == NULL || container->retry_soon) {
 633                         /* just waiting to get O_EXCL access */
 634                         ts.tv_sec = 0;
 635                         ts.tv_nsec = 20000000ULL;
 636                 }
 637                 sigprocmask(SIG_UNBLOCK, NULL, &set);
 638                 sigdelset(&set, SIGUSR1);
 639                 monitor_loop_cnt |= 1;
 640                 rv = pselect(maxfd+1, NULL, NULL, &rfds, &ts, &set);
 641                 monitor_loop_cnt += 1;
 642                 if (rv == -1) {
 643                         if (errno == EINTR) {
 644                                 rv = 0;
 645                                 dprintf("monitor: caught signal\n");
 646                         } else
 647                                 dprintf("monitor: error %d in pselect\n",
 648                                         errno);
 649                 }
 650                 #ifdef DEBUG
 651                 else
 652                         dprint_wake_reasons(&rfds);
 653                 #endif
 654                 container->retry_soon = 0;
 655         }
 656
 657         if (update_queue) {
 658                 struct metadata_update *this;
 659
 660                 for (this = update_queue; this ; this = this->next)
 661                         container->ss->process_update(container, this);
 662
 663                 update_queue_handled = update_queue;
 664                 update_queue = NULL;
 665                 signal_manager();
 666                 container->ss->sync_metadata(container);
 667         }
 668
 669         rv = 0;
 670         dirty_arrays = 0;
 671         for (a = *aap; a ; a = a->next) {
 672
 673                 if (a->replaces && !discard_this) {
 674                         struct active_array **ap;
 675                         for (ap = &a->next; *ap && *ap != a->replaces;
 676                              ap = & (*ap)->next)
 677                                 ;
 678                         if (*ap)
 679                                 *ap = (*ap)->next;
 680                         discard_this = a->replaces;
 681                         a->replaces = NULL;
 682                         /* FIXME check if device->state_fd need to be cleared?*/
 683                         signal_manager();
 684                 }
 685                 if (a->container && !a->to_remove) {
 686                         int ret = read_and_act(a);
 687                         rv |= 1;
 688                         dirty_arrays += !!(ret & ARRAY_DIRTY);
 689                         /* when terminating stop manipulating the array after it
 690                          * is clean, but make sure read_and_act() is given a
 691                          * chance to handle 'active_idle'
 692                          */
 693                         if (sigterm && !(ret & ARRAY_DIRTY))
 694                                 a->container = NULL; /* stop touching this array */
 695                         if (ret & ARRAY_BUSY)
 696                                 container->retry_soon = 1;
 697                 }
 698         }
 699
 700         /* propagate failures across container members */
 701         for (a = *aap; a ; a = a->next) {
 702                 if (!a->container || a->to_remove)
 703                         continue;
 704                 for (mdi = a->info.devs ; mdi ; mdi = mdi->next)
 705                         if (mdi->curr_state & DS_FAULTY)
 706                                 reconcile_failed(*aap, mdi);
 707         }
 708
 709         return rv;
 710 }
 711
 712 void do_monitor(struct supertype *container)
 713 {
 714         int rv;
 715         int first = 1;
 716         do {
 717                 rv = wait_and_act(container, first);
 718                 first = 0;
 719         } while (rv >= 0);
 720 }