]>
git.ipfire.org Git - thirdparty/mdadm.git/blob - managemon.c
2 * mdmon - monitor external metadata arrays
4 * Copyright (C) 2007-2009 Neil Brown <neilb@suse.de>
5 * Copyright (C) 2007-2009 Intel Corporation
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.
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
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.
22 * The management thread for monitoring active md arrays.
23 * This thread does things which might block such as memory
27 * - Find out about new arrays in this container.
28 * Allocate the data structures and open the files.
30 * For this we watch /proc/mdstat and find new arrays with
31 * metadata type that confirms sharing. e.g. "md4"
32 * When we find a new array we slip it into the list of
33 * arrays and signal 'monitor' by writing to a pipe.
35 * - Respond to reshape requests by allocating new data structures
36 * and opening new files.
38 * These come as a change to raid_disks. We allocate a new
39 * version of the data structures and slip it into the list.
40 * 'monitor' will notice and release the old version.
41 * Changes to level, chunksize, layout.. do not need re-allocation.
42 * Reductions in raid_disks don't really either, but we handle
43 * them the same way for consistency.
45 * - When a device is added to the container, we add it to the metadata
48 * - Deal with degraded array
49 * We only do this when first noticing the array is degraded.
50 * This can be when we first see the array, when sync completes or
51 * when recovery completes.
53 * Check if number of failed devices suggests recovery is needed, and
55 * Ask metadata to allocate a spare device
56 * Add device as not in_sync and give a role
58 * Open sysfs files and pass to monitor.
59 * Make sure that monitor Starts recovery....
61 * - Pass on metadata updates from external programs such as
62 * mdadm creating a new array.
65 * It might involve adding a new array or changing the status of
66 * a spare, or any reconfig that the kernel doesn't get involved in.
68 * The required updates are received via a named pipe. There will
69 * be one named pipe for each container. Each message contains a
70 * sync marker: 0x5a5aa5a5, A byte count, and the message. This is
71 * passed to the metadata handler which will interpret and process it.
72 * For 'DDF' messages are internal data blocks with the leading
73 * 'magic number' signifying what sort of data it is.
78 * We select on /proc/mdstat and the named pipe.
79 * We create new arrays or updated version of arrays and slip
80 * them into the head of the list, then signal 'monitor' via a pipe write.
81 * 'monitor' will notice and place the old array on a return list.
82 * Metadata updates are placed on a queue just like they arrive
83 * from the named pipe.
85 * When new arrays are found based on correct metadata string, we
86 * need to identify them with an entry in the metadata. Maybe we require
87 * the metadata to be mdX/NN when NN is the index into an appropriate table.
93 * - Watch for spares to be added to the container, and write updated
95 * - Watch for new arrays using this container, confirm they match metadata
96 * and if so, start monitoring them
97 * - Watch for spares being added to monitored arrays. This shouldn't
98 * happen, as we should do all the adding. Just remove them.
99 * - Watch for change in raid-disks, chunk-size, etc. Update metadata and
107 #include <sys/syscall.h>
108 #include <sys/socket.h>
111 static void close_aa(struct active_array
*aa
)
115 for (d
= aa
->info
.devs
; d
; d
= d
->next
) {
116 close(d
->recovery_fd
);
122 if (aa
->action_fd
>= 0)
123 close(aa
->action_fd
);
124 if (aa
->info
.state_fd
>= 0)
125 close(aa
->info
.state_fd
);
126 if (aa
->resync_start_fd
>= 0)
127 close(aa
->resync_start_fd
);
128 if (aa
->metadata_fd
>= 0)
129 close(aa
->metadata_fd
);
130 if (aa
->sync_completed_fd
>= 0)
131 close(aa
->sync_completed_fd
);
132 if (aa
->safe_mode_delay_fd
>= 0)
133 close(aa
->safe_mode_delay_fd
);
136 static void free_aa(struct active_array
*aa
)
138 /* Note that this doesn't close fds if they are being used
139 * by a clone. ->container will be set for a clone
141 dprintf("sys_name: %s\n", aa
->info
.sys_name
);
144 while (aa
->info
.devs
) {
145 struct mdinfo
*d
= aa
->info
.devs
;
146 aa
->info
.devs
= d
->next
;
152 static struct active_array
*duplicate_aa(struct active_array
*aa
)
154 struct active_array
*newa
= xmalloc(sizeof(*newa
));
155 struct mdinfo
**dp1
, **dp2
;
159 newa
->replaces
= NULL
;
160 newa
->info
.next
= NULL
;
162 dp2
= &newa
->info
.devs
;
164 for (dp1
= &aa
->info
.devs
; *dp1
; dp1
= &(*dp1
)->next
) {
166 if ((*dp1
)->state_fd
< 0)
169 d
= xmalloc(sizeof(*d
));
179 static void wakeup_monitor(void)
181 /* tgkill(getpid(), mon_tid, SIGUSR1); */
183 syscall(SYS_tgkill
, pid
, mon_tid
, SIGUSR1
);
186 static void remove_old(void)
189 discard_this
->next
= NULL
;
190 free_aa(discard_this
);
191 if (pending_discard
== discard_this
)
192 pending_discard
= NULL
;
198 static void replace_array(struct supertype
*container
,
199 struct active_array
*old
,
200 struct active_array
*new)
202 /* To replace an array, we add it to the top of the list
203 * marked with ->replaces to point to the original.
204 * 'monitor' will take the original out of the list
205 * and put it on 'discard_this'. We take it from there
209 while (pending_discard
) {
210 while (discard_this
== NULL
)
214 pending_discard
= old
;
216 new->next
= container
->arrays
;
217 container
->arrays
= new;
221 struct metadata_update
*update_queue
= NULL
;
222 struct metadata_update
*update_queue_handled
= NULL
;
223 struct metadata_update
*update_queue_pending
= NULL
;
225 static void free_updates(struct metadata_update
**update
)
228 struct metadata_update
*this = *update
;
229 void **space_list
= this->space_list
;
231 *update
= this->next
;
235 void *space
= space_list
;
236 space_list
= *space_list
;
243 void check_update_queue(struct supertype
*container
)
245 free_updates(&update_queue_handled
);
247 if (update_queue
== NULL
&&
248 update_queue_pending
) {
249 update_queue
= update_queue_pending
;
250 update_queue_pending
= NULL
;
255 static void queue_metadata_update(struct metadata_update
*mu
)
257 struct metadata_update
**qp
;
259 qp
= &update_queue_pending
;
261 qp
= & ((*qp
)->next
);
265 static void add_disk_to_container(struct supertype
*st
, struct mdinfo
*sd
)
269 struct metadata_update
*update
= NULL
;
270 mdu_disk_info_t dk
= {
272 .major
= sd
->disk
.major
,
273 .minor
= sd
->disk
.minor
,
278 dprintf("add %d:%d to container\n", sd
->disk
.major
, sd
->disk
.minor
);
283 sprintf(nm
, "%d:%d", sd
->disk
.major
, sd
->disk
.minor
);
284 dfd
= dev_open(nm
, O_RDWR
);
288 st
->update_tail
= &update
;
289 st
->ss
->add_to_super(st
, &dk
, dfd
, NULL
, INVALID_SECTORS
);
290 st
->ss
->write_init_super(st
);
291 queue_metadata_update(update
);
292 st
->update_tail
= NULL
;
296 * Create and queue update structure about the removed disks.
297 * The update is prepared by super type handler and passed to the monitor
300 static void remove_disk_from_container(struct supertype
*st
, struct mdinfo
*sd
)
302 struct metadata_update
*update
= NULL
;
303 mdu_disk_info_t dk
= {
305 .major
= sd
->disk
.major
,
306 .minor
= sd
->disk
.minor
,
310 dprintf("remove %d:%d from container\n",
311 sd
->disk
.major
, sd
->disk
.minor
);
313 st
->update_tail
= &update
;
314 st
->ss
->remove_from_super(st
, &dk
);
315 /* FIXME this write_init_super shouldn't be here.
316 * We have it after add_to_super to write to new device,
317 * but with 'remove' we don't ant to write to that device!
319 st
->ss
->write_init_super(st
);
320 queue_metadata_update(update
);
321 st
->update_tail
= NULL
;
324 static void manage_container(struct mdstat_ent
*mdstat
,
325 struct supertype
*container
)
327 /* Of interest here are:
328 * - if a new device has been added to the container, we
329 * add it to the array ignoring any metadata on it.
330 * - if a device has been removed from the container, we
331 * remove it from the device list and update the metadata.
332 * FIXME should we look for compatible metadata and take hints
333 * about spare assignment.... probably not.
335 if (mdstat
->devcnt
!= container
->devcnt
) {
336 struct mdinfo
**cdp
, *cd
, *di
, *mdi
;
339 /* read /sys/block/NAME/md/dev-??/block/dev to find out
340 * what is there, and compare with container->info.devs
341 * To see what is removed and what is added.
342 * These need to be remove from, or added to, the array
344 mdi
= sysfs_read(-1, mdstat
->devnm
, GET_DEVS
);
346 /* invalidate the current count so we can try again */
347 container
->devcnt
= -1;
351 /* check for removals */
352 for (cdp
= &container
->devs
; *cdp
; ) {
354 for (di
= mdi
->devs
; di
; di
= di
->next
)
355 if (di
->disk
.major
== (*cdp
)->disk
.major
&&
356 di
->disk
.minor
== (*cdp
)->disk
.minor
) {
363 remove_disk_from_container(container
, cd
);
369 /* check for additions */
370 for (di
= mdi
->devs
; di
; di
= di
->next
) {
371 for (cd
= container
->devs
; cd
; cd
= cd
->next
)
372 if (di
->disk
.major
== cd
->disk
.major
&&
373 di
->disk
.minor
== cd
->disk
.minor
)
376 struct mdinfo
*newd
= xmalloc(sizeof(*newd
));
379 add_disk_to_container(container
, newd
);
383 container
->devcnt
= mdstat
->devcnt
;
387 static int sysfs_open2(char *devnum
, char *name
, char *attr
)
389 int fd
= sysfs_open(devnum
, name
, attr
);
391 /* seq_file in the kernel allocates buffer space
392 * on the first read. Do that now so 'monitor'
396 if (read(fd
, buf
, sizeof(buf
)) < 0)
397 /* pretend not to ignore return value */
403 static int disk_init_and_add(struct mdinfo
*disk
, struct mdinfo
*clone
,
404 struct active_array
*aa
)
410 disk
->recovery_fd
= sysfs_open2(aa
->info
.sys_name
, disk
->sys_name
,
412 if (disk
->recovery_fd
< 0)
414 disk
->state_fd
= sysfs_open2(aa
->info
.sys_name
, disk
->sys_name
, "state");
415 if (disk
->state_fd
< 0) {
416 close(disk
->recovery_fd
);
419 disk
->bb_fd
= sysfs_open2(aa
->info
.sys_name
, disk
->sys_name
,
421 if (disk
->bb_fd
< 0) {
422 close(disk
->recovery_fd
);
423 close(disk
->state_fd
);
426 disk
->ubb_fd
= sysfs_open2(aa
->info
.sys_name
, disk
->sys_name
,
427 "unacknowledged_bad_blocks");
428 if (disk
->ubb_fd
< 0) {
429 close(disk
->recovery_fd
);
430 close(disk
->state_fd
);
434 disk
->prev_state
= read_dev_state(disk
->state_fd
);
435 disk
->curr_state
= disk
->prev_state
;
436 disk
->next
= aa
->info
.devs
;
437 aa
->info
.devs
= disk
;
442 static void manage_member(struct mdstat_ent
*mdstat
,
443 struct active_array
*a
)
445 /* Compare mdstat info with known state of member array.
446 * We do not need to look for device state changes here, that
447 * is dealt with by the monitor.
449 * If a reshape is being requested, monitor will have noticed
450 * that sync_action changed and will have set check_reshape.
451 * We just need to see if new devices have appeared. All metadata
452 * updates will already have been processed.
454 * We also want to handle degraded arrays here by
455 * trying to find and assign a spare.
456 * We do that whenever the monitor tells us too.
460 struct supertype
*container
= a
->container
;
463 if (container
== NULL
)
464 /* Raced with something */
467 if (mdstat
->active
) {
469 a
->info
.array
.raid_disks
= mdstat
->raid_disks
;
473 mdi
= sysfs_read(-1, mdstat
->devnm
,
474 GET_COMPONENT
|GET_CONSISTENCY_POLICY
);
476 a
->info
.component_size
= mdi
->component_size
;
477 a
->info
.consistency_policy
= mdi
->consistency_policy
;
482 if (sysfs_get_str(&a
->info
, NULL
, "metadata_version", buf
, sizeof(buf
)) > 0)
483 frozen
= buf
[9] == '-';
485 frozen
= 1; /* can't read metadata_version assume the worst */
487 /* If sync_action is not 'idle' then don't try recovery now */
489 sysfs_get_str(&a
->info
, NULL
, "sync_action",
490 buf
, sizeof(buf
)) > 0 && strncmp(buf
, "idle", 4) != 0)
494 int level
= map_name(pers
, mdstat
->level
);
495 if (level
== 0 || level
== LEVEL_LINEAR
) {
500 else if (a
->info
.array
.level
!= level
&& level
> 0) {
501 struct active_array
*newa
= duplicate_aa(a
);
503 newa
->info
.array
.level
= level
;
504 replace_array(container
, a
, newa
);
510 /* we are after monitor kick,
511 * so container field can be cleared - check it again
513 if (a
->container
== NULL
)
516 if (sigterm
&& a
->info
.safe_mode_delay
!= 1 &&
517 a
->safe_mode_delay_fd
>= 0) {
518 long int new_delay
= 1;
522 len
= snprintf(delay
, sizeof(delay
), "0.%03ld\n", new_delay
);
523 if (write(a
->safe_mode_delay_fd
, delay
, len
) == len
)
524 a
->info
.safe_mode_delay
= new_delay
;
527 /* We don't check the array while any update is pending, as it
528 * might container a change (such as a spare assignment) which
529 * could affect our decisions.
531 if (a
->check_degraded
&& !frozen
&&
532 update_queue
== NULL
&& update_queue_pending
== NULL
) {
533 struct metadata_update
*updates
= NULL
;
534 struct mdinfo
*newdev
= NULL
;
535 struct active_array
*newa
;
538 a
->check_degraded
= 0;
540 /* The array may not be degraded, this is just a good time
543 newdev
= container
->ss
->activate_spare(a
, &updates
);
547 newa
= duplicate_aa(a
);
550 /* prevent the kernel from activating the disk(s) before we
553 dprintf("freezing %s\n", a
->info
.sys_name
);
554 sysfs_set_str(&a
->info
, NULL
, "sync_action", "frozen");
556 /* Add device to array and set offset/size/slot.
557 * and open files for each newdev */
558 for (d
= newdev
; d
; d
= d
->next
) {
561 newd
= xmalloc(sizeof(*newd
));
562 if (sysfs_add_disk(&newa
->info
, d
, 0) < 0) {
566 disk_init_and_add(newd
, d
, newa
);
568 queue_metadata_update(updates
);
570 while (update_queue_pending
|| update_queue
) {
571 check_update_queue(container
);
574 replace_array(container
, a
, newa
);
575 if (sysfs_set_str(&a
->info
, NULL
,
576 "sync_action", "recover") == 0)
577 newa
->prev_action
= recover
;
578 dprintf("recovery started on %s\n", a
->info
.sys_name
);
585 free_updates(&updates
);
588 if (a
->check_reshape
) {
589 /* mdadm might have added some devices to the array.
590 * We want to disk_init_and_add any such device to a
591 * duplicate_aa and replace a with that.
592 * mdstat doesn't have enough info so we sysfs_read
593 * and look for new stuff.
595 struct mdinfo
*info
, *d
, *d2
, *newd
;
596 unsigned long long array_size
;
597 struct active_array
*newa
= NULL
;
598 a
->check_reshape
= 0;
599 info
= sysfs_read(-1, mdstat
->devnm
,
600 GET_DEVS
|GET_OFFSET
|GET_SIZE
|GET_STATE
);
603 for (d
= info
->devs
; d
; d
= d
->next
) {
604 if (d
->disk
.raid_disk
< 0)
606 for (d2
= a
->info
.devs
; d2
; d2
= d2
->next
)
607 if (d2
->disk
.raid_disk
==
611 /* already have this one */
614 newa
= duplicate_aa(a
);
618 newd
= xmalloc(sizeof(*newd
));
619 disk_init_and_add(newd
, d
, newa
);
621 if (sysfs_get_ll(info
, NULL
, "array_size", &array_size
) == 0 &&
622 a
->info
.custom_array_size
> array_size
*2) {
623 sysfs_set_num(info
, NULL
, "array_size",
624 a
->info
.custom_array_size
/2);
629 replace_array(container
, a
, newa
);
633 static int aa_ready(struct active_array
*aa
)
636 int level
= aa
->info
.array
.level
;
638 for (d
= aa
->info
.devs
; d
; d
= d
->next
)
642 if (aa
->info
.state_fd
< 0)
645 if (level
> 0 && (aa
->action_fd
< 0 || aa
->resync_start_fd
< 0))
654 static void manage_new(struct mdstat_ent
*mdstat
,
655 struct supertype
*container
,
656 struct active_array
*victim
)
658 /* A new array has appeared in this container.
659 * Hopefully it is already recorded in the metadata.
660 * Check, then create the new array to report it to
664 struct active_array
*new;
665 struct mdinfo
*mdi
, *di
;
671 /* check if array is ready to be monitored */
672 if (!mdstat
->active
|| !mdstat
->level
)
674 if (strcmp(mdstat
->level
, "raid0") == 0 ||
675 strcmp(mdstat
->level
, "linear") == 0)
678 mdi
= sysfs_read(-1, mdstat
->devnm
,
679 GET_LEVEL
|GET_CHUNK
|GET_DISKS
|GET_COMPONENT
|
680 GET_SAFEMODE
|GET_DEVS
|GET_OFFSET
|GET_SIZE
|GET_STATE
|
681 GET_LAYOUT
|GET_DEVS_ALL
);
685 new = xcalloc(1, sizeof(*new));
687 strcpy(new->info
.sys_name
, mdstat
->devnm
);
689 new->prev_state
= new->curr_state
= new->next_state
= inactive
;
690 new->prev_action
= new->curr_action
= new->next_action
= idle
;
692 new->container
= container
;
694 inst
= to_subarray(mdstat
, container
->devnm
);
696 new->info
.array
= mdi
->array
;
697 new->info
.component_size
= mdi
->component_size
;
699 for (i
= 0; i
< new->info
.array
.raid_disks
; i
++) {
700 struct mdinfo
*newd
= xmalloc(sizeof(*newd
));
702 for (di
= mdi
->devs
; di
; di
= di
->next
)
703 if (i
== di
->disk
.raid_disk
)
706 if (disk_init_and_add(newd
, di
, new) != 0) {
711 if (failed
> new->info
.array
.failed_disks
) {
712 /* we cannot properly monitor without all working disks */
713 new->container
= NULL
;
719 new->action_fd
= sysfs_open2(new->info
.sys_name
, NULL
, "sync_action");
720 new->info
.state_fd
= sysfs_open2(new->info
.sys_name
, NULL
, "array_state");
721 new->resync_start_fd
= sysfs_open2(new->info
.sys_name
, NULL
, "resync_start");
722 new->metadata_fd
= sysfs_open2(new->info
.sys_name
, NULL
, "metadata_version");
723 new->sync_completed_fd
= sysfs_open2(new->info
.sys_name
, NULL
, "sync_completed");
724 new->safe_mode_delay_fd
= sysfs_open2(new->info
.sys_name
, NULL
,
727 dprintf("inst: %s action: %d state: %d\n", inst
,
728 new->action_fd
, new->info
.state_fd
);
730 if (mdi
->safe_mode_delay
>= 50)
731 /* Normal start, mdadm set this. */
732 new->info
.safe_mode_delay
= mdi
->safe_mode_delay
;
734 /* Restart, just pick a number */
735 new->info
.safe_mode_delay
= 5000;
736 sysfs_set_safemode(&new->info
, new->info
.safe_mode_delay
);
738 /* reshape_position is set by mdadm in sysfs
739 * read this information for new arrays only (empty victim)
741 if ((victim
== NULL
) &&
742 (sysfs_get_str(mdi
, NULL
, "sync_action", buf
, 40) > 0) &&
743 (strncmp(buf
, "reshape", 7) == 0)) {
744 if (sysfs_get_ll(mdi
, NULL
, "reshape_position",
745 &new->last_checkpoint
) != 0)
746 new->last_checkpoint
= 0;
748 int data_disks
= mdi
->array
.raid_disks
;
749 if (mdi
->array
.level
== 4 || mdi
->array
.level
== 5)
751 if (mdi
->array
.level
== 6)
754 new->last_checkpoint
/= data_disks
;
756 dprintf("mdmon: New monitored array is under reshape.\n"
757 " Last checkpoint is: %llu\n",
758 new->last_checkpoint
);
763 /* if everything checks out tell the metadata handler we want to
764 * manage this instance
766 if (!aa_ready(new) || container
->ss
->open_new(container
, new, inst
) < 0) {
767 pr_err("failed to monitor %s\n",
768 mdstat
->metadata_version
);
769 new->container
= NULL
;
772 replace_array(container
, victim
, new);
774 new->check_degraded
= 1;
775 manage_member(mdstat
, new);
780 void manage(struct mdstat_ent
*mdstat
, struct supertype
*container
)
782 /* We have just read mdstat and need to compare it with
783 * the known active arrays.
784 * Arrays with the wrong metadata are ignored.
787 for ( ; mdstat
; mdstat
= mdstat
->next
) {
788 struct active_array
*a
;
789 if (strcmp(mdstat
->devnm
, container
->devnm
) == 0) {
790 manage_container(mdstat
, container
);
793 if (!is_container_member(mdstat
, container
->devnm
))
794 /* Not for this array */
796 /* Looks like a member of this container */
797 for (a
= container
->arrays
; a
; a
= a
->next
) {
798 if (strcmp(mdstat
->devnm
, a
->info
.sys_name
) == 0) {
799 if (a
->container
&& a
->to_remove
== 0)
800 manage_member(mdstat
, a
);
804 if ((a
== NULL
|| !a
->container
) && !sigterm
)
805 manage_new(mdstat
, container
, a
);
809 static void handle_message(struct supertype
*container
, struct metadata_update
*msg
)
811 /* queue this metadata update through to the monitor */
813 struct metadata_update
*mu
;
816 while (update_queue_pending
|| update_queue
) {
817 check_update_queue(container
);
821 if (msg
->len
== 0) { /* ping_monitor */
824 cnt
= monitor_loop_cnt
;
826 cnt
+= 2; /* wait until next pselect */
828 cnt
+= 3; /* wait for 2 pselects */
831 while (monitor_loop_cnt
- cnt
< 0)
833 } else if (msg
->len
== -1) { /* ping_manager */
834 struct mdstat_ent
*mdstat
= mdstat_read(1, 0);
836 manage(mdstat
, container
);
838 } else if (!sigterm
) {
839 mu
= xmalloc(sizeof(*mu
));
844 mu
->space_list
= NULL
;
846 if (container
->ss
->prepare_update
)
847 if (!container
->ss
->prepare_update(container
, mu
))
849 queue_metadata_update(mu
);
853 void read_sock(struct supertype
*container
)
856 struct metadata_update msg
;
859 int tmo
= 3; /* 3 second timeout before hanging up the socket */
861 fd
= accept(container
->sock
, NULL
, NULL
);
865 fl
= fcntl(fd
, F_GETFL
, 0);
867 fcntl(fd
, F_SETFL
, fl
);
872 /* read and validate the message */
873 if (receive_message(fd
, &msg
, tmo
) == 0) {
874 handle_message(container
, &msg
);
876 /* ping reply with version */
878 msg
.len
= strlen(Version
) + 1;
879 if (send_message(fd
, &msg
, tmo
) < 0)
881 } else if (ack(fd
, tmo
) < 0)
886 } while (!terminate
);
892 int manager_ready
= 0;
893 void do_manager(struct supertype
*container
)
895 struct mdstat_ent
*mdstat
;
898 sigprocmask(SIG_UNBLOCK
, NULL
, &set
);
899 sigdelset(&set
, SIGUSR1
);
900 sigdelset(&set
, SIGTERM
);
907 /* Can only 'manage' things if 'monitor' is not making
908 * structural changes to metadata, so need to check
911 if (update_queue
== NULL
) {
912 mdstat
= mdstat_read(1, 0);
914 manage(mdstat
, container
);
916 read_sock(container
);
922 check_update_queue(container
);
929 if (update_queue
== NULL
)
930 mdstat_wait_fd(container
->sock
, &set
);
932 /* If an update is happening, just wait for signal */
933 pselect(0, NULL
, NULL
, NULL
, NULL
, &set
);