2 Bacula® - The Network Backup Solution
4 Copyright (C) 2000-2009 Free Software Foundation Europe e.V.
6 The main author of Bacula is Kern Sibbald, with contributions from
7 many others, a complete list can be found in the file AUTHORS.
8 This program is Free Software; you can redistribute it and/or
9 modify it under the terms of version two of the GNU General Public
10 License as published by the Free Software Foundation and included
13 This program is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
23 Bacula® is a registered trademark of Kern Sibbald.
24 The licensor of Bacula is the Free Software Foundation Europe
25 (FSFE), Fiduciary Program, Sumatrastrasse 25, 8006 Zürich,
26 Switzerland, email:ftf@fsfeurope.org.
29 * Volume management functions for Storage Daemon
33 * Split from reserve.c October 2008
35 * Version $Id: reserve.c 7380 2008-07-14 10:42:59Z kerns $
42 const int dbglvl = 150;
44 static dlist *vol_list = NULL;
45 static brwlock_t vol_list_lock;
46 static dlist *read_vol_list = NULL;
47 static bthread_mutex_t read_vol_lock = BTHREAD_MUTEX_PRIORITY(PRIO_SD_READ_VOL_LIST);
49 /* Forward referenced functions */
50 static void free_vol_item(VOLRES *vol);
51 static VOLRES *new_vol_item(DCR *dcr, const char *VolumeName);
52 static void debug_list_volumes(const char *imsg);
55 * For append volumes the key is the VolumeName.
57 static int my_compare(void *item1, void *item2)
59 return strcmp(((VOLRES *)item1)->vol_name, ((VOLRES *)item2)->vol_name);
63 * For read volumes the key is JobId, VolumeName.
65 static int read_compare(void *item1, void *item2)
67 VOLRES *vol1 = (VOLRES *)item1;
68 VOLRES *vol2 = (VOLRES *)item2;
70 if (vol1->get_jobid() == vol2->get_jobid()) {
71 return strcmp(vol1->vol_name, vol2->vol_name);
73 if (vol1->get_jobid() < vol2->get_jobid()) {
80 bool is_vol_list_empty()
82 return vol_list->empty();
85 int vol_list_lock_count = 0;
88 * Initialized the main volume list. Note, we are using a recursive lock.
90 void init_vol_list_lock()
93 if ((errstat=rwl_init(&vol_list_lock, PRIO_SD_VOL_LIST)) != 0) {
95 Emsg1(M_ABORT, 0, _("Unable to initialize volume list lock. ERR=%s\n"),
96 be.bstrerror(errstat));
100 void term_vol_list_lock()
102 rwl_destroy(&vol_list_lock);
106 * This allows a given thread to recursively call to lock_volumes()
108 void _lock_volumes(const char *file, int line)
111 vol_list_lock_count++;
112 if ((errstat=rwl_writelock_p(&vol_list_lock, file, line)) != 0) {
114 Emsg2(M_ABORT, 0, "rwl_writelock failure. stat=%d: ERR=%s\n",
115 errstat, be.bstrerror(errstat));
119 void _unlock_volumes()
122 vol_list_lock_count--;
123 if ((errstat=rwl_writeunlock(&vol_list_lock)) != 0) {
125 Emsg2(M_ABORT, 0, "rwl_writeunlock failure. stat=%d: ERR=%s\n",
126 errstat, be.bstrerror(errstat));
130 void lock_read_volumes(const char *file="**Unknown", int line=0)
132 bthread_mutex_lock_p(&read_vol_lock, file, line);
135 void unlock_read_volumes()
137 bthread_mutex_unlock(&read_vol_lock);
141 * Add a volume to the read list.
142 * Note, we use VOLRES because it simplifies the code
143 * even though, the only part of VOLRES that we need is
144 * the volume name. The same volume may be in the list
145 * multiple times, but each one is distinguished by the
146 * JobId. We use JobId, VolumeName as the key.
147 * We can get called multiple times for the same volume because
148 * when parsing the bsr, the volume name appears multiple times.
150 void add_read_volume(JCR *jcr, const char *VolumeName)
155 nvol = new_vol_item(NULL, VolumeName);
156 nvol->set_jobid(jcr->JobId);
157 vol = (VOLRES *)read_vol_list->binary_insert(nvol, read_compare);
160 Dmsg2(dbglvl, "read_vol=%s JobId=%d already in list.\n", VolumeName, jcr->JobId);
162 Dmsg2(dbglvl, "add read_vol=%s JobId=%d\n", VolumeName, jcr->JobId);
164 unlock_read_volumes();
168 * Remove a given volume name from the read list.
170 void remove_read_volume(JCR *jcr, const char *VolumeName)
174 vol.vol_name = bstrdup(VolumeName);
175 vol.set_jobid(jcr->JobId);
176 fvol = (VOLRES *)read_vol_list->binary_search(&vol, read_compare);
179 Dmsg3(dbglvl, "remove_read_vol=%s JobId=%d found=%d\n", VolumeName, jcr->JobId, fvol!=NULL);
182 read_vol_list->remove(fvol);
185 unlock_read_volumes();
189 * List Volumes -- this should be moved to status.c
196 static void debug_list_volumes(const char *imsg)
199 POOL_MEM msg(PM_MESSAGE);
202 foreach_dlist(vol, vol_list) {
204 Mmsg(msg, "List %s: %s in_use=%d on device %s\n", imsg,
205 vol->vol_name, vol->is_in_use(), vol->dev->print_name());
207 Mmsg(msg, "List %s: %s in_use=%d no dev\n", imsg, vol->vol_name,
210 Dmsg1(dbglvl, "%s", msg.c_str());
218 * List Volumes -- this should be moved to status.c
220 void list_volumes(void sendit(const char *msg, int len, void *sarg), void *arg)
223 POOL_MEM msg(PM_MESSAGE);
227 foreach_dlist(vol, vol_list) {
228 DEVICE *dev = vol->dev;
230 len = Mmsg(msg, "%s on device %s\n", vol->vol_name, dev->print_name());
231 sendit(msg.c_str(), len, arg);
232 len = Mmsg(msg, " Reader=%d writers=%d devres=%d volinuse=%d\n",
233 dev->can_read()?1:0, dev->num_writers, dev->num_reserved(),
235 sendit(msg.c_str(), len, arg);
237 len = Mmsg(msg, "%s no device. volinuse= %d\n", vol->vol_name,
239 sendit(msg.c_str(), len, arg);
245 foreach_dlist(vol, read_vol_list) {
246 len = Mmsg(msg, "%s read volume JobId=%d\n", vol->vol_name,
248 sendit(msg.c_str(), len, arg);
250 unlock_read_volumes();
255 * Create a Volume item to put in the Volume list
256 * Ensure that the device points to it.
258 static VOLRES *new_vol_item(DCR *dcr, const char *VolumeName)
261 vol = (VOLRES *)malloc(sizeof(VOLRES));
262 memset(vol, 0, sizeof(VOLRES));
263 vol->vol_name = bstrdup(VolumeName);
266 Dmsg3(dbglvl, "new Vol=%s at %p dev=%s\n",
267 VolumeName, vol->vol_name, vol->dev->print_name());
272 static void free_vol_item(VOLRES *vol)
287 * Put a new Volume entry in the Volume list. This
288 * effectively reserves the volume so that it will
289 * not be mounted again.
291 * If the device has any current volume associated with it,
292 * and it is a different Volume, and the device is not busy,
293 * we release the old Volume item and insert the new one.
295 * It is assumed that the device is free and locked so that
296 * we can change the device structure.
298 * Some details of the Volume list handling:
300 * 1. The Volume list entry must be attached to the drive (rather than
301 * attached to a job as it currently is. I.e. the drive that "owns"
302 * the volume (in use, mounted)
303 * must point to the volume (still to be maintained in a list).
305 * 2. The Volume is entered in the list when a drive is reserved.
307 * 3. When a drive is in use, the device code must appropriately update the
308 * volume name as it changes (currently the list is static -- an entry is
309 * removed when the Volume is no longer reserved, in use or mounted).
310 * The new code must keep the same list entry as long as the drive
311 * has any volume associated with it but the volume name in the list
312 * must be updated when the drive has a different volume mounted.
314 * 4. A job that has reserved a volume, can un-reserve the volume, and if the
315 * volume is not mounted, and not reserved, and not in use, it will be
316 * removed from the list.
318 * 5. If a job wants to reserve a drive with a different Volume from the one on
319 * the drive, it can re-use the drive for the new Volume.
321 * 6. If a job wants a Volume that is in a different drive, it can either use the
322 * other drive or take the volume, only if the other drive is not in use or
325 * One nice aspect of this is that the reserve use count and the writer use count
326 * already exist and are correctly programmed and will need no changes -- use
327 * counts are always very tricky.
329 * The old code had a concept of "reserving" a Volume, but was changed
330 * to reserving and using a drive. A volume is must be attached to (owned by) a
331 * drive and can move from drive to drive or be unused given certain specific
332 * conditions of the drive. The key is that the drive must "own" the Volume.
333 * The old code had the job (dcr) owning the volume (more or less). The job was
334 * to change the insertion and removal of the volumes from the list to be based
335 * on the drive rather than the job.
337 * Return: VOLRES entry on success
338 * NULL volume busy on another drive
340 VOLRES *reserve_volume(DCR *dcr, const char *VolumeName)
343 DEVICE * volatile dev = dcr->dev;
345 if (job_canceled(dcr->jcr)) {
350 Dmsg2(dbglvl, "enter reserve_volume=%s drive=%s\n", VolumeName,
351 dcr->dev->print_name());
353 * We lock the reservations system here to ensure
354 * when adding a new volume that no newly scheduled
355 * job can reserve it.
358 debug_list_volumes("begin reserve_volume");
360 * First, remove any old volume attached to this device as it
365 Dmsg4(dbglvl, "Vol attached=%s, newvol=%s volinuse=%d on %s\n",
366 vol->vol_name, VolumeName, vol->is_in_use(), dev->print_name());
368 * Make sure we don't remove the current volume we are inserting
369 * because it was probably inserted by another job, or it
370 * is not being used and is marked as not reserved.
372 if (strcmp(vol->vol_name, VolumeName) == 0) {
373 Dmsg2(dbglvl, "=== set reserved vol=%s dev=%s\n", VolumeName,
374 vol->dev->print_name());
375 goto get_out; /* Volume already on this device */
377 /* Don't release a volume if it was reserved by someone other than us */
378 if (vol->is_in_use() && !dcr->reserved_volume) {
379 Dmsg1(dbglvl, "Cannot free vol=%s. It is reserved.\n", vol->vol_name);
380 vol = NULL; /* vol in use */
383 Dmsg2(dbglvl, "reserve_vol free vol=%s at %p\n", vol->vol_name, vol->vol_name);
384 /* If old Volume is still mounted, must unload it */
385 if (strcmp(vol->vol_name, dev->VolHdr.VolumeName) == 0) {
386 Dmsg0(50, "set_unload\n");
387 dev->set_unload(); /* have to unload current volume */
389 free_volume(dev); /* Release old volume entry */
390 debug_list_volumes("reserve_vol free");
394 /* Create a new Volume entry */
395 nvol = new_vol_item(dcr, VolumeName);
398 * Now try to insert the new Volume
400 vol = (VOLRES *)vol_list->binary_insert(nvol, my_compare);
402 Dmsg2(dbglvl, "Found vol=%s dev-same=%d\n", vol->vol_name, dev==vol->dev);
404 * At this point, a Volume with this name already is in the list,
405 * so we simply release our new Volume entry. Note, this should
406 * only happen if we are moving the volume from one drive to another.
408 Dmsg2(dbglvl, "reserve_vol free-tmp vol=%s at %p\n",
409 vol->vol_name, vol->vol_name);
411 * Clear dev pointer so that free_vol_item() doesn't
412 * take away our volume.
414 nvol->dev = NULL; /* don't zap dev entry */
418 Dmsg2(dbglvl, "dev=%s vol->dev=%s\n", dev->print_name(), vol->dev->print_name());
422 * Check if we are trying to use the Volume on a different drive
424 * vol->dev is where the Volume we want is
426 if (dev != vol->dev) {
427 /* Caller wants to switch Volume to another device */
428 if (!vol->dev->is_busy() && !vol->is_swapping()) {
430 Dmsg3(dbglvl, "==== Swap vol=%s from dev=%s to %s\n",
431 VolumeName, vol->dev->print_name(), dev->print_name());
432 free_volume(dev); /* free any volume attached to our drive */
433 Dmsg0(50, "set_unload\n");
434 dev->set_unload(); /* Unload any volume that is on our drive */
435 dcr->dev = vol->dev; /* temp point to other dev */
436 slot = get_autochanger_loaded_slot(dcr); /* get slot on other drive */
437 dcr->dev = dev; /* restore dev */
438 vol->set_slot(slot); /* save slot */
439 vol->dev->set_unload(); /* unload the other drive */
440 vol->set_swapping(); /* swap from other drive */
441 dev->swap_dev = vol->dev; /* remember to get this vol */
442 dev->set_load(); /* then reload on our drive */
443 vol->dev->vol = NULL; /* remove volume from other drive */
444 vol->dev = dev; /* point the Volume at our drive */
445 dev->vol = vol; /* point our drive at the Volume */
447 Dmsg5(dbglvl, "==== Swap not possible Vol busy=%d swap=%d vol=%s from dev=%s to %s\n",
448 vol->dev->is_busy(), vol->is_swapping(),
449 VolumeName, vol->dev->print_name(), dev->print_name());
450 if (vol->is_swapping() && dev->swap_dev) {
451 Dmsg2(dbglvl, "Swap vol=%s dev=%s\n", vol->vol_name, dev->swap_dev->print_name());
453 Dmsg1(dbglvl, "swap_dev=%p\n", dev->swap_dev);
455 debug_list_volumes("failed swap");
456 vol = NULL; /* device busy */
463 dev->vol = vol; /* point to newly inserted volume */
468 Dmsg2(dbglvl, "=== set in_use. vol=%s dev=%s\n", vol->vol_name,
469 vol->dev->print_name());
471 dcr->reserved_volume = true;
472 bstrncpy(dcr->VolumeName, vol->vol_name, sizeof(dcr->VolumeName));
474 debug_list_volumes("end new volume");
480 * Switch from current device to given device
484 void switch_device(DCR *dcr, DEVICE *dev)
489 memcpy(&save_dcr, dcr, sizeof(save_dcr));
490 clean_device(dcr); /* clean up the dcr */
492 dcr->dev = dev; /* get new device pointer */
493 Jmsg(dcr->jcr, M_INFO, 0, _("Device switch. New device %s chosen.\n"),
494 dcr->dev->print_name());
496 bstrncpy(dcr->VolumeName, save_dcr.VolumeName, sizeof(dcr->VolumeName));
497 bstrncpy(dcr->media_type, save_dcr.media_type, sizeof(dcr->media_type));
498 dcr->VolCatInfo.Slot = save_dcr.VolCatInfo.Slot;
499 bstrncpy(dcr->pool_name, save_dcr.pool_name, sizeof(dcr->pool_name));
500 bstrncpy(dcr->pool_type, save_dcr.pool_type, sizeof(dcr->pool_type));
501 bstrncpy(dcr->dev_name, dev->dev_name, sizeof(dcr->dev_name));
503 // dcr->set_reserved();
510 * Search for a Volume name in the Volume list.
512 * Returns: VOLRES entry on success
513 * NULL if the Volume is not in the list
515 VOLRES *find_volume(const char *VolumeName)
519 if (vol_list->empty()) {
522 /* Do not lock reservations here */
524 vol.vol_name = bstrdup(VolumeName);
525 fvol = (VOLRES *)vol_list->binary_search(&vol, my_compare);
527 Dmsg2(dbglvl, "find_vol=%s found=%d\n", VolumeName, fvol!=NULL);
528 debug_list_volumes("find_volume");
534 * Search for a Volume name in the read Volume list.
536 * Returns: VOLRES entry on success
537 * NULL if the Volume is not in the list
539 static VOLRES *find_read_volume(const char *VolumeName)
543 if (read_vol_list->empty()) {
544 Dmsg0(dbglvl, "find_read_vol: read_vol_list empty.\n");
547 /* Do not lock reservations here */
549 vol.vol_name = bstrdup(VolumeName);
550 /* Note, we do want a simple my_compare on volume name only here */
551 fvol = (VOLRES *)read_vol_list->binary_search(&vol, my_compare);
553 Dmsg2(dbglvl, "find_read_vol=%s found=%d\n", VolumeName, fvol!=NULL);
554 unlock_read_volumes();
560 * Free a Volume from the Volume list if it is no longer used
561 * Note, for tape drives we want to remember where the Volume
562 * was when last used, so rather than free the volume entry,
563 * we simply mark it "not reserved" so when the drive is really
564 * needed for another volume, we can reuse it.
566 * Returns: true if the Volume found and "removed" from the list
567 * false if the Volume is not in the list or is in use
569 bool volume_unused(DCR *dcr)
571 DEVICE *dev = dcr->dev;
574 Dmsg1(dbglvl, "vol_unused: no vol on %s\n", dev->print_name());
575 debug_list_volumes("null vol cannot unreserve_volume");
578 if (dev->vol->is_swapping()) {
579 Dmsg1(dbglvl, "vol_unused: vol being swapped on %s\n", dev->print_name());
580 Dmsg1(dbglvl, "=== clear in_use vol=%s\n", dev->vol->vol_name);
581 dev->vol->clear_in_use();
582 debug_list_volumes("swapping vol cannot free_volume");
587 * If this is a tape, we do not free the volume, rather we wait
588 * until the autoloader unloads it, or until another tape is
589 * explicitly read in this drive. This allows the SD to remember
590 * where the tapes are or last were.
592 Dmsg4(dbglvl, "=== set not reserved vol=%s num_writers=%d dev_reserved=%d dev=%s\n",
593 dev->vol->vol_name, dev->num_writers, dev->num_reserved(), dev->print_name());
594 Dmsg1(dbglvl, "=== clear in_use vol=%s\n", dev->vol->vol_name);
595 dev->vol->clear_in_use();
596 if (dev->is_tape() || dev->is_autochanger()) {
600 * Note, this frees the volume reservation entry, but the
601 * file descriptor remains open with the OS.
603 return free_volume(dev);
608 * Unconditionally release the volume entry
610 bool free_volume(DEVICE *dev)
614 if (dev->vol == NULL) {
615 Dmsg1(dbglvl, "No vol on dev %s\n", dev->print_name());
620 /* Don't free a volume while it is being swapped */
621 if (!vol->is_swapping()) {
622 Dmsg1(dbglvl, "=== clear in_use vol=%s\n", vol->vol_name);
624 vol_list->remove(vol);
625 Dmsg2(dbglvl, "=== remove volume %s dev=%s\n", vol->vol_name, dev->print_name());
627 debug_list_volumes("free_volume");
629 Dmsg1(dbglvl, "=== cannot clear swapping vol=%s\n", vol->vol_name);
636 /* Create the Volume list */
637 void create_volume_lists()
640 if (vol_list == NULL) {
641 vol_list = New(dlist(vol, &vol->link));
643 if (read_vol_list == NULL) {
644 read_vol_list = New(dlist(vol, &vol->link));
649 * Free normal append volumes list
651 static void free_volume_list()
656 foreach_dlist(vol, vol_list) {
658 Dmsg2(dbglvl, "free vol_list Volume=%s dev=%s\n", vol->vol_name, vol->dev->print_name());
660 Dmsg1(dbglvl, "free vol_list Volume=%s No dev\n", vol->vol_name);
663 vol->vol_name = NULL;
671 /* Release all Volumes from the list */
672 void free_volume_lists()
676 free_volume_list(); /* normal append list */
680 foreach_dlist(vol, read_vol_list) {
682 Dmsg2(dbglvl, "free read_vol_list Volume=%s dev=%s\n", vol->vol_name, vol->dev->print_name());
684 Dmsg1(dbglvl, "free read_vol_list Volume=%s No dev\n", vol->vol_name);
687 vol->vol_name = NULL;
689 delete read_vol_list;
690 read_vol_list = NULL;
691 unlock_read_volumes();
696 * Determine if caller can write on volume
698 bool DCR::can_i_write_volume()
702 vol = find_read_volume(VolumeName);
704 Dmsg1(100, "Found in read list; cannot write vol=%s\n", VolumeName);
707 return can_i_use_volume();
711 * Determine if caller can read or write volume
713 bool DCR::can_i_use_volume()
718 if (job_canceled(jcr)) {
722 vol = find_volume(VolumeName);
724 Dmsg1(dbglvl, "Vol=%s not in use.\n", VolumeName);
725 goto get_out; /* vol not in list */
727 ASSERT(vol->dev != NULL);
729 if (dev == vol->dev) { /* same device OK */
730 Dmsg1(dbglvl, "Vol=%s on same dev.\n", VolumeName);
733 Dmsg3(dbglvl, "Vol=%s on %s we have %s\n", VolumeName,
734 vol->dev->print_name(), dev->print_name());
736 /* ***FIXME*** check this ... */
737 if (!vol->dev->is_busy()) {
738 Dmsg2(dbglvl, "Vol=%s dev=%s not busy.\n", VolumeName, vol->dev->print_name());
741 Dmsg2(dbglvl, "Vol=%s dev=%s busy.\n", VolumeName, vol->dev->print_name());
743 Dmsg2(dbglvl, "Vol=%s in use by %s.\n", VolumeName, vol->dev->print_name());
753 * Create a temporary copy of the volume list. We do this,
754 * to avoid having the volume list locked during the
755 * call to reserve_device(), which would cause a deadlock.
756 * Note, we may want to add an update counter on the vol_list
757 * so that if it is modified while we are traversing the copy
758 * we can take note and act accordingly (probably redo the
759 * search at least a few times).
761 dlist *dup_vol_list(JCR *jcr)
763 dlist *temp_vol_list;
767 Dmsg0(dbglvl, "lock volumes\n");
769 Dmsg0(dbglvl, "duplicate vol list\n");
770 temp_vol_list = New(dlist(vol, &vol->link));
771 foreach_dlist(vol, vol_list) {
773 VOLRES *tvol = (VOLRES *)malloc(sizeof(VOLRES));
774 memset(tvol, 0, sizeof(VOLRES));
775 tvol->vol_name = bstrdup(vol->vol_name);
776 tvol->dev = vol->dev;
777 nvol = (VOLRES *)temp_vol_list->binary_insert(tvol, my_compare);
779 tvol->dev = NULL; /* don't zap dev entry */
781 Pmsg0(000, "Logic error. Duplicating vol list hit duplicate.\n");
782 Jmsg(jcr, M_WARNING, 0, "Logic error. Duplicating vol list hit duplicate.\n");
785 Dmsg0(dbglvl, "unlock volumes\n");
787 return temp_vol_list;
791 * Free the specified temp list.
793 void free_temp_vol_list(dlist *temp_vol_list)
795 dlist *save_vol_list;
798 save_vol_list = vol_list;
799 vol_list = temp_vol_list;
800 free_volume_list(); /* release temp_vol_list */
801 vol_list = save_vol_list;
802 Dmsg0(dbglvl, "deleted temp vol list\n");
803 Dmsg0(dbglvl, "unlock volumes\n");
805 debug_list_volumes("after free temp table");