2 Bacula® - The Network Backup Solution
4 Copyright (C) 2000-2012 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 three of the GNU Affero 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 Affero 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
40 const int dbglvl = 150;
42 static dlist *vol_list = NULL;
43 static brwlock_t vol_list_lock;
44 static dlist *read_vol_list = NULL;
45 static bthread_mutex_t read_vol_lock = BTHREAD_MUTEX_PRIORITY(PRIO_SD_READ_VOL_LIST);
47 /* Forward referenced functions */
48 static void free_vol_item(VOLRES *vol);
49 static VOLRES *new_vol_item(DCR *dcr, const char *VolumeName);
50 static void debug_list_volumes(const char *imsg);
53 * For append volumes the key is the VolumeName.
55 static int my_compare(void *item1, void *item2)
57 return strcmp(((VOLRES *)item1)->vol_name, ((VOLRES *)item2)->vol_name);
61 * For read volumes the key is JobId, VolumeName.
63 static int read_compare(void *item1, void *item2)
65 VOLRES *vol1 = (VOLRES *)item1;
66 VOLRES *vol2 = (VOLRES *)item2;
68 if (vol1->get_jobid() == vol2->get_jobid()) {
69 return strcmp(vol1->vol_name, vol2->vol_name);
71 if (vol1->get_jobid() < vol2->get_jobid()) {
78 bool is_vol_list_empty()
80 return vol_list->empty();
83 int vol_list_lock_count = 0;
86 * Initialized the main volume list. Note, we are using a recursive lock.
88 void init_vol_list_lock()
91 if ((errstat=rwl_init(&vol_list_lock, PRIO_SD_VOL_LIST)) != 0) {
93 Emsg1(M_ABORT, 0, _("Unable to initialize volume list lock. ERR=%s\n"),
94 be.bstrerror(errstat));
98 void term_vol_list_lock()
100 rwl_destroy(&vol_list_lock);
104 * This allows a given thread to recursively call to lock_volumes()
106 void _lock_volumes(const char *file, int line)
109 vol_list_lock_count++;
110 if ((errstat=rwl_writelock_p(&vol_list_lock, file, line)) != 0) {
112 Emsg2(M_ABORT, 0, "rwl_writelock failure. stat=%d: ERR=%s\n",
113 errstat, be.bstrerror(errstat));
117 void _unlock_volumes()
120 vol_list_lock_count--;
121 if ((errstat=rwl_writeunlock(&vol_list_lock)) != 0) {
123 Emsg2(M_ABORT, 0, "rwl_writeunlock failure. stat=%d: ERR=%s\n",
124 errstat, be.bstrerror(errstat));
128 void lock_read_volumes(const char *file="**Unknown", int line=0)
130 bthread_mutex_lock_p(&read_vol_lock, file, line);
133 void unlock_read_volumes()
135 bthread_mutex_unlock(&read_vol_lock);
139 * Add a volume to the read list.
140 * Note, we use VOLRES because it simplifies the code
141 * even though, the only part of VOLRES that we need is
142 * the volume name. The same volume may be in the list
143 * multiple times, but each one is distinguished by the
144 * JobId. We use JobId, VolumeName as the key.
145 * We can get called multiple times for the same volume because
146 * when parsing the bsr, the volume name appears multiple times.
148 void add_read_volume(JCR *jcr, const char *VolumeName)
153 nvol = new_vol_item(NULL, VolumeName);
154 nvol->set_jobid(jcr->JobId);
155 vol = (VOLRES *)read_vol_list->binary_insert(nvol, read_compare);
158 Dmsg2(dbglvl, "read_vol=%s JobId=%d already in list.\n", VolumeName, jcr->JobId);
160 Dmsg2(dbglvl, "add read_vol=%s JobId=%d\n", VolumeName, jcr->JobId);
162 unlock_read_volumes();
166 * Remove a given volume name from the read list.
168 void remove_read_volume(JCR *jcr, const char *VolumeName)
172 vol.vol_name = bstrdup(VolumeName);
173 vol.set_jobid(jcr->JobId);
174 fvol = (VOLRES *)read_vol_list->binary_search(&vol, read_compare);
177 Dmsg3(dbglvl, "remove_read_vol=%s JobId=%d found=%d\n", VolumeName, jcr->JobId, fvol!=NULL);
180 read_vol_list->remove(fvol);
183 unlock_read_volumes();
184 // pthread_cond_broadcast(&wait_next_vol);
188 * List Volumes -- this should be moved to status.c
195 static void debug_list_volumes(const char *imsg)
198 POOL_MEM msg(PM_MESSAGE);
201 foreach_dlist(vol, vol_list) {
203 Mmsg(msg, "List %s: %s in_use=%d swap=%d on device %s\n", imsg,
204 vol->vol_name, vol->is_in_use(), vol->is_swapping(), vol->dev->print_name());
206 Mmsg(msg, "List %s: %s in_use=%d swap=%d no dev\n", imsg, vol->vol_name,
207 vol->is_in_use(), vol->is_swapping());
209 Dmsg1(dbglvl, "%s", msg.c_str());
217 * List Volumes -- this should be moved to status.c
219 void list_volumes(void sendit(const char *msg, int len, void *sarg), void *arg)
222 POOL_MEM msg(PM_MESSAGE);
226 foreach_dlist(vol, vol_list) {
227 DEVICE *dev = vol->dev;
229 len = Mmsg(msg, "%s on device %s\n", vol->vol_name, dev->print_name());
230 sendit(msg.c_str(), len, arg);
231 len = Mmsg(msg, " Reader=%d writers=%d devres=%d volinuse=%d\n",
232 dev->can_read()?1:0, dev->num_writers, dev->num_reserved(),
234 sendit(msg.c_str(), len, arg);
236 len = Mmsg(msg, "%s no device. volinuse= %d\n", vol->vol_name,
238 sendit(msg.c_str(), len, arg);
244 foreach_dlist(vol, read_vol_list) {
245 len = Mmsg(msg, "%s read volume JobId=%d\n", vol->vol_name,
247 sendit(msg.c_str(), len, arg);
249 unlock_read_volumes();
254 * Create a Volume item to put in the Volume list
255 * Ensure that the device points to it.
257 static VOLRES *new_vol_item(DCR *dcr, const char *VolumeName)
260 vol = (VOLRES *)malloc(sizeof(VOLRES));
261 memset(vol, 0, sizeof(VOLRES));
262 vol->vol_name = bstrdup(VolumeName);
265 Dmsg3(dbglvl, "new Vol=%s at %p dev=%s\n",
266 VolumeName, vol->vol_name, vol->dev->print_name());
271 static void free_vol_item(VOLRES *vol)
286 * Put a new Volume entry in the Volume list. This
287 * effectively reserves the volume so that it will
288 * not be mounted again.
290 * If the device has any current volume associated with it,
291 * and it is a different Volume, and the device is not busy,
292 * we release the old Volume item and insert the new one.
294 * It is assumed that the device is free and locked so that
295 * we can change the device structure.
297 * Some details of the Volume list handling:
299 * 1. The Volume list entry must be attached to the drive (rather than
300 * attached to a job as it currently is. I.e. the drive that "owns"
301 * the volume (in use, mounted)
302 * must point to the volume (still to be maintained in a list).
304 * 2. The Volume is entered in the list when a drive is reserved.
306 * 3. When a drive is in use, the device code must appropriately update the
307 * volume name as it changes (currently the list is static -- an entry is
308 * removed when the Volume is no longer reserved, in use or mounted).
309 * The new code must keep the same list entry as long as the drive
310 * has any volume associated with it but the volume name in the list
311 * must be updated when the drive has a different volume mounted.
313 * 4. A job that has reserved a volume, can un-reserve the volume, and if the
314 * volume is not mounted, and not reserved, and not in use, it will be
315 * removed from the list.
317 * 5. If a job wants to reserve a drive with a different Volume from the one on
318 * the drive, it can re-use the drive for the new Volume.
320 * 6. If a job wants a Volume that is in a different drive, it can either use the
321 * other drive or take the volume, only if the other drive is not in use or
324 * One nice aspect of this is that the reserve use count and the writer use count
325 * already exist and are correctly programmed and will need no changes -- use
326 * counts are always very tricky.
328 * The old code had a concept of "reserving" a Volume, but was changed
329 * to reserving and using a drive. A volume is must be attached to (owned by) a
330 * drive and can move from drive to drive or be unused given certain specific
331 * conditions of the drive. The key is that the drive must "own" the Volume.
332 * The old code had the job (dcr) owning the volume (more or less). The job was
333 * to change the insertion and removal of the volumes from the list to be based
334 * on the drive rather than the job.
336 * Return: VOLRES entry on success
337 * NULL volume busy on another drive
339 VOLRES *reserve_volume(DCR *dcr, const char *VolumeName)
342 DEVICE * volatile dev = dcr->dev;
344 if (job_canceled(dcr->jcr)) {
349 Dmsg2(dbglvl, "enter reserve_volume=%s drive=%s\n", VolumeName,
350 dcr->dev->print_name());
352 * We lock the reservations system here to ensure
353 * when adding a new volume that no newly scheduled
354 * job can reserve it.
357 debug_list_volumes("begin reserve_volume");
359 * First, remove any old volume attached to this device as it
364 Dmsg4(dbglvl, "Vol attached=%s, newvol=%s volinuse=%d on %s\n",
365 vol->vol_name, VolumeName, vol->is_in_use(), dev->print_name());
367 * Make sure we don't remove the current volume we are inserting
368 * because it was probably inserted by another job, or it
369 * is not being used and is marked as not reserved.
371 if (strcmp(vol->vol_name, VolumeName) == 0) {
372 Dmsg2(dbglvl, "=== set reserved vol=%s dev=%s\n", VolumeName,
373 vol->dev->print_name());
374 goto get_out; /* Volume already on this device */
376 /* Don't release a volume if it was reserved by someone other than us */
377 if (vol->is_in_use() && !dcr->reserved_volume) {
378 Dmsg1(dbglvl, "Cannot free vol=%s. It is reserved.\n", vol->vol_name);
379 vol = NULL; /* vol in use */
382 Dmsg2(dbglvl, "reserve_vol free vol=%s at %p\n", vol->vol_name, vol->vol_name);
383 /* If old Volume is still mounted, must unload it */
384 if (strcmp(vol->vol_name, dev->VolHdr.VolumeName) == 0) {
385 Dmsg0(50, "set_unload\n");
386 dev->set_unload(); /* have to unload current volume */
388 free_volume(dev); /* Release old volume entry */
389 debug_list_volumes("reserve_vol free");
393 /* Create a new Volume entry */
394 nvol = new_vol_item(dcr, VolumeName);
397 * Now try to insert the new Volume
399 vol = (VOLRES *)vol_list->binary_insert(nvol, my_compare);
401 Dmsg2(dbglvl, "Found vol=%s dev-same=%d\n", vol->vol_name, dev==vol->dev);
403 * At this point, a Volume with this name already is in the list,
404 * so we simply release our new Volume entry. Note, this should
405 * only happen if we are moving the volume from one drive to another.
407 Dmsg2(dbglvl, "reserve_vol free-tmp vol=%s at %p\n",
408 vol->vol_name, vol->vol_name);
410 * Clear dev pointer so that free_vol_item() doesn't
411 * take away our volume.
413 nvol->dev = NULL; /* don't zap dev entry */
417 Dmsg2(dbglvl, "dev=%s vol->dev=%s\n", dev->print_name(), vol->dev->print_name());
421 * Check if we are trying to use the Volume on a different drive
423 * vol->dev is where the Volume we want is
425 if (dev != vol->dev) {
426 /* Caller wants to switch Volume to another device */
427 if (!vol->dev->is_busy() && !vol->is_swapping()) {
429 Dmsg3(dbglvl, "==== Swap vol=%s from dev=%s to %s\n",
430 VolumeName, vol->dev->print_name(), dev->print_name());
431 free_volume(dev); /* free any volume attached to our drive */
432 Dmsg1(50, "set_unload dev=%s\n", dev->print_name());
433 dev->set_unload(); /* Unload any volume that is on our drive */
434 dcr->set_dev(vol->dev); /* temp point to other dev */
435 slot = get_autochanger_loaded_slot(dcr); /* get slot on other drive */
436 dcr->set_dev(dev); /* restore dev */
437 vol->set_slot(slot); /* save slot */
438 vol->dev->set_unload(); /* unload the other drive */
439 vol->set_swapping(); /* swap from other drive */
440 dev->swap_dev = vol->dev; /* remember to get this vol */
441 dev->set_load(); /* then reload on our drive */
442 vol->dev->vol = NULL; /* remove volume from other drive */
443 vol->dev = dev; /* point the Volume at our drive */
444 dev->vol = vol; /* point our drive at the Volume */
446 Jmsg7(dcr->jcr, M_WARNING, 0, "Need volume from other drive, "
447 "but swap not possible. Status: read=%d num_writers=%d "
448 "num_reserve=%d swap=%d vol=%s from dev=%s to %s\n",
449 vol->dev->can_read(), vol->dev->num_writers,
450 vol->dev->num_reserved(), vol->is_swapping(),
451 VolumeName, vol->dev->print_name(), dev->print_name());
452 if (vol->is_swapping() && dev->swap_dev) {
453 Dmsg3(dbglvl, "Swap failed vol=%s from=%s to dev=%s\n",
454 vol->vol_name, dev->swap_dev->print_name(), dev->print_name());
456 Dmsg3(dbglvl, "Swap failed vol=%s from=%p to dev=%s\n",
457 vol->vol_name, dev->swap_dev, dev->print_name());
459 debug_list_volumes("failed swap");
460 vol = NULL; /* device busy */
467 dev->vol = vol; /* point to newly inserted volume */
472 Dmsg2(dbglvl, "=== set in_use. vol=%s dev=%s\n", vol->vol_name,
473 vol->dev->print_name());
475 dcr->reserved_volume = true;
476 bstrncpy(dcr->VolumeName, vol->vol_name, sizeof(dcr->VolumeName));
478 debug_list_volumes("end new volume");
484 * Search for a Volume name in the Volume list.
486 * Returns: VOLRES entry on success
487 * NULL if the Volume is not in the list
489 VOLRES *find_volume(const char *VolumeName)
493 if (vol_list->empty()) {
496 /* Do not lock reservations here */
498 vol.vol_name = bstrdup(VolumeName);
499 fvol = (VOLRES *)vol_list->binary_search(&vol, my_compare);
501 Dmsg2(dbglvl, "find_vol=%s found=%d\n", VolumeName, fvol!=NULL);
502 debug_list_volumes("find_volume");
508 * Search for a Volume name in the read Volume list.
510 * Returns: VOLRES entry on success
511 * NULL if the Volume is not in the list
513 static VOLRES *find_read_volume(const char *VolumeName)
517 if (read_vol_list->empty()) {
518 Dmsg0(dbglvl, "find_read_vol: read_vol_list empty.\n");
521 /* Do not lock reservations here */
523 vol.vol_name = bstrdup(VolumeName);
524 /* Note, we do want a simple my_compare on volume name only here */
525 fvol = (VOLRES *)read_vol_list->binary_search(&vol, my_compare);
527 Dmsg2(dbglvl, "find_read_vol=%s found=%d\n", VolumeName, fvol!=NULL);
528 unlock_read_volumes();
534 * Free a Volume from the Volume list if it is no longer used
535 * Note, for tape drives we want to remember where the Volume
536 * was when last used, so rather than free the volume entry,
537 * we simply mark it "not reserved" so when the drive is really
538 * needed for another volume, we can reuse it.
540 * Returns: true if the Volume found and "removed" from the list
541 * false if the Volume is not in the list or is in use
543 bool volume_unused(DCR *dcr)
545 DEVICE *dev = dcr->dev;
548 Dmsg1(dbglvl, "vol_unused: no vol on %s\n", dev->print_name());
549 debug_list_volumes("null vol cannot unreserve_volume");
553 Dmsg1(dbglvl, "=== clear in_use vol=%s\n", dev->vol->vol_name);
554 dev->vol->clear_in_use();
556 if (dev->vol->is_swapping()) {
557 Dmsg1(dbglvl, "vol_unused: vol being swapped on %s\n", dev->print_name());
558 debug_list_volumes("swapping vol cannot free_volume");
563 * If this is a tape, we do not free the volume, rather we wait
564 * until the autoloader unloads it, or until another tape is
565 * explicitly read in this drive. This allows the SD to remember
566 * where the tapes are or last were.
568 Dmsg4(dbglvl, "=== set not reserved vol=%s num_writers=%d dev_reserved=%d dev=%s\n",
569 dev->vol->vol_name, dev->num_writers, dev->num_reserved(), dev->print_name());
570 if (dev->is_tape() || dev->is_autochanger()) {
574 * Note, this frees the volume reservation entry, but the
575 * file descriptor remains open with the OS.
577 return free_volume(dev);
582 * Unconditionally release the volume entry
584 bool free_volume(DEVICE *dev)
591 Dmsg1(dbglvl, "No vol on dev %s\n", dev->print_name());
595 /* Don't free a volume while it is being swapped */
596 if (!vol->is_swapping()) {
597 Dmsg1(dbglvl, "=== clear in_use vol=%s\n", vol->vol_name);
599 vol_list->remove(vol);
600 Dmsg2(dbglvl, "=== remove volume %s dev=%s\n", vol->vol_name, dev->print_name());
602 debug_list_volumes("free_volume");
604 Dmsg1(dbglvl, "=== cannot clear swapping vol=%s\n", vol->vol_name);
607 // pthread_cond_broadcast(&wait_next_vol);
612 /* Create the Volume list */
613 void create_volume_lists()
616 if (vol_list == NULL) {
617 vol_list = New(dlist(vol, &vol->link));
619 if (read_vol_list == NULL) {
620 read_vol_list = New(dlist(vol, &vol->link));
625 * Free normal append volumes list
627 static void free_volume_list()
632 foreach_dlist(vol, vol_list) {
634 Dmsg2(dbglvl, "free vol_list Volume=%s dev=%s\n", vol->vol_name, vol->dev->print_name());
636 Dmsg1(dbglvl, "free vol_list Volume=%s No dev\n", vol->vol_name);
639 vol->vol_name = NULL;
647 /* Release all Volumes from the list */
648 void free_volume_lists()
652 free_volume_list(); /* normal append list */
656 foreach_dlist(vol, read_vol_list) {
658 Dmsg2(dbglvl, "free read_vol_list Volume=%s dev=%s\n", vol->vol_name, vol->dev->print_name());
660 Dmsg1(dbglvl, "free read_vol_list Volume=%s No dev\n", vol->vol_name);
663 vol->vol_name = NULL;
665 delete read_vol_list;
666 read_vol_list = NULL;
667 unlock_read_volumes();
672 * Determine if caller can write on volume
674 bool DCR::can_i_write_volume()
678 vol = find_read_volume(VolumeName);
680 Dmsg1(100, "Found in read list; cannot write vol=%s\n", VolumeName);
683 return can_i_use_volume();
687 * Determine if caller can read or write volume
689 bool DCR::can_i_use_volume()
694 if (job_canceled(jcr)) {
698 vol = find_volume(VolumeName);
700 Dmsg1(dbglvl, "Vol=%s not in use.\n", VolumeName);
701 goto get_out; /* vol not in list */
703 ASSERT(vol->dev != NULL);
705 if (dev == vol->dev) { /* same device OK */
706 Dmsg1(dbglvl, "Vol=%s on same dev.\n", VolumeName);
709 Dmsg3(dbglvl, "Vol=%s on %s we have %s\n", VolumeName,
710 vol->dev->print_name(), dev->print_name());
712 /* ***FIXME*** check this ... */
713 if (!vol->dev->is_busy()) {
714 Dmsg2(dbglvl, "Vol=%s dev=%s not busy.\n", VolumeName, vol->dev->print_name());
717 Dmsg2(dbglvl, "Vol=%s dev=%s busy.\n", VolumeName, vol->dev->print_name());
719 Dmsg2(dbglvl, "Vol=%s in use by %s.\n", VolumeName, vol->dev->print_name());
729 * Create a temporary copy of the volume list. We do this,
730 * to avoid having the volume list locked during the
731 * call to reserve_device(), which would cause a deadlock.
732 * Note, we may want to add an update counter on the vol_list
733 * so that if it is modified while we are traversing the copy
734 * we can take note and act accordingly (probably redo the
735 * search at least a few times).
737 dlist *dup_vol_list(JCR *jcr)
739 dlist *temp_vol_list;
743 Dmsg0(dbglvl, "lock volumes\n");
745 Dmsg0(dbglvl, "duplicate vol list\n");
746 temp_vol_list = New(dlist(vol, &vol->link));
747 foreach_dlist(vol, vol_list) {
749 VOLRES *tvol = (VOLRES *)malloc(sizeof(VOLRES));
750 memset(tvol, 0, sizeof(VOLRES));
751 tvol->vol_name = bstrdup(vol->vol_name);
752 tvol->dev = vol->dev;
753 nvol = (VOLRES *)temp_vol_list->binary_insert(tvol, my_compare);
755 tvol->dev = NULL; /* don't zap dev entry */
757 Pmsg0(000, "Logic error. Duplicating vol list hit duplicate.\n");
758 Jmsg(jcr, M_WARNING, 0, "Logic error. Duplicating vol list hit duplicate.\n");
761 Dmsg0(dbglvl, "unlock volumes\n");
763 return temp_vol_list;
767 * Free the specified temp list.
769 void free_temp_vol_list(dlist *temp_vol_list)
771 dlist *save_vol_list;
774 save_vol_list = vol_list;
775 vol_list = temp_vol_list;
776 free_volume_list(); /* release temp_vol_list */
777 vol_list = save_vol_list;
778 Dmsg0(dbglvl, "deleted temp vol list\n");
779 Dmsg0(dbglvl, "unlock volumes\n");
781 debug_list_volumes("after free temp table");