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 pthread_mutex_t read_vol_lock = PTHREAD_MUTEX_INITIALIZER;
49 /* Forward referenced functions */
50 static void free_vol_item(VOLRES *vol);
51 static VOLRES *new_vol_item(DCR *dcr, const char *VolumeName);
54 * For append volumes the key is the VolumeName.
56 static int my_compare(void *item1, void *item2)
58 return strcmp(((VOLRES *)item1)->vol_name, ((VOLRES *)item2)->vol_name);
62 * For read volumes the key is JobId, VolumeName.
64 static int read_compare(void *item1, void *item2)
66 VOLRES *vol1 = (VOLRES *)item1;
67 VOLRES *vol2 = (VOLRES *)item2;
69 if (vol1->get_jobid() == vol2->get_jobid()) {
70 return strcmp(vol1->vol_name, vol2->vol_name);
72 if (vol1->get_jobid() < vol2->get_jobid()) {
79 bool is_vol_list_empty()
81 return vol_list->empty();
84 int vol_list_lock_count = 0;
87 * Initialized the main volume list. Note, we are using a recursive lock.
89 void init_vol_list_lock()
92 if ((errstat=rwl_init(&vol_list_lock)) != 0) {
94 Emsg1(M_ABORT, 0, _("Unable to initialize volume list lock. ERR=%s\n"),
95 be.bstrerror(errstat));
99 void term_vol_list_lock()
101 rwl_destroy(&vol_list_lock);
107 * This allows a given thread to recursively call to lock_volumes()
112 vol_list_lock_count++;
113 if ((errstat=rwl_writelock(&vol_list_lock)) != 0) {
115 Emsg2(M_ABORT, 0, "rwl_writelock failure. stat=%d: ERR=%s\n",
116 errstat, be.bstrerror(errstat));
120 void _unlock_volumes()
123 vol_list_lock_count--;
124 if ((errstat=rwl_writeunlock(&vol_list_lock)) != 0) {
126 Emsg2(M_ABORT, 0, "rwl_writeunlock failure. stat=%d: ERR=%s\n",
127 errstat, be.bstrerror(errstat));
131 void lock_read_volumes()
136 void unlock_read_volumes()
142 * Add a volume to the read list.
143 * Note, we use VOLRES because it simplifies the code
144 * even though, the only part of VOLRES that we need is
145 * the volume name. The same volume may be in the list
146 * multiple times, but each one is distinguished by the
147 * JobId. We use JobId, VolumeName as the key.
148 * We can get called multiple times for the same volume because
149 * when parsing the bsr, the volume name appears multiple times.
151 void add_read_volume(JCR *jcr, const char *VolumeName)
156 nvol = new_vol_item(NULL, VolumeName);
157 nvol->set_jobid(jcr->JobId);
158 vol = (VOLRES *)read_vol_list->binary_insert(nvol, read_compare);
161 Dmsg2(dbglvl, "read_vol=%s JobId=%d already in list.\n", VolumeName, jcr->JobId);
163 Dmsg2(dbglvl, "add read_vol=%s JobId=%d\n", VolumeName, jcr->JobId);
165 unlock_read_volumes();
169 * Remove a given volume name from the read list.
171 void remove_read_volume(JCR *jcr, const char *VolumeName)
175 vol.vol_name = bstrdup(VolumeName);
176 vol.set_jobid(jcr->JobId);
177 fvol = (VOLRES *)read_vol_list->binary_search(&vol, read_compare);
180 Dmsg3(dbglvl, "remove_read_vol=%s JobId=%d found=%d\n", VolumeName, jcr->JobId, fvol!=NULL);
182 debug_list_volumes("remove_read_volume");
184 read_vol_list->remove(fvol);
187 unlock_read_volumes();
191 * List Volumes -- this should be moved to status.c
198 void debug_list_volumes(const char *imsg)
201 POOL_MEM msg(PM_MESSAGE);
204 foreach_dlist(vol, vol_list) {
206 Mmsg(msg, "List %s: %s in_use=%d on device %s\n", imsg,
207 vol->vol_name, vol->is_in_use(), vol->dev->print_name());
209 Mmsg(msg, "List %s: %s in_use=%d no dev\n", imsg, vol->vol_name,
212 Dmsg1(dbglvl, "%s", msg.c_str());
220 * List Volumes -- this should be moved to status.c
222 void list_volumes(void sendit(const char *msg, int len, void *sarg), void *arg)
225 POOL_MEM msg(PM_MESSAGE);
229 foreach_dlist(vol, vol_list) {
230 DEVICE *dev = vol->dev;
232 len = Mmsg(msg, "%s on device %s\n", vol->vol_name, dev->print_name());
233 sendit(msg.c_str(), len, arg);
234 len = Mmsg(msg, " Reader=%d writers=%d devres=%d volinuse=%d\n",
235 dev->can_read()?1:0, dev->num_writers, dev->num_reserved(),
237 sendit(msg.c_str(), len, arg);
239 len = Mmsg(msg, "%s no device. volinuse= %d\n", vol->vol_name,
241 sendit(msg.c_str(), len, arg);
247 foreach_dlist(vol, read_vol_list) {
248 len = Mmsg(msg, "%s read volume JobId=%d\n", vol->vol_name,
250 sendit(msg.c_str(), len, arg);
252 unlock_read_volumes();
257 * Create a Volume item to put in the Volume list
258 * Ensure that the device points to it.
260 static VOLRES *new_vol_item(DCR *dcr, const char *VolumeName)
263 vol = (VOLRES *)malloc(sizeof(VOLRES));
264 memset(vol, 0, sizeof(VOLRES));
265 vol->vol_name = bstrdup(VolumeName);
268 Dmsg3(dbglvl, "new Vol=%s at %p dev=%s\n",
269 VolumeName, vol->vol_name, vol->dev->print_name());
274 static void free_vol_item(VOLRES *vol)
289 * Put a new Volume entry in the Volume list. This
290 * effectively reserves the volume so that it will
291 * not be mounted again.
293 * If the device has any current volume associated with it,
294 * and it is a different Volume, and the device is not busy,
295 * we release the old Volume item and insert the new one.
297 * It is assumed that the device is free and locked so that
298 * we can change the device structure.
300 * Some details of the Volume list handling:
302 * 1. The Volume list entry must be attached to the drive (rather than
303 * attached to a job as it currently is. I.e. the drive that "owns"
304 * the volume (in use, mounted)
305 * must point to the volume (still to be maintained in a list).
307 * 2. The Volume is entered in the list when a drive is reserved.
309 * 3. When a drive is in use, the device code must appropriately update the
310 * volume name as it changes (currently the list is static -- an entry is
311 * removed when the Volume is no longer reserved, in use or mounted).
312 * The new code must keep the same list entry as long as the drive
313 * has any volume associated with it but the volume name in the list
314 * must be updated when the drive has a different volume mounted.
316 * 4. A job that has reserved a volume, can un-reserve the volume, and if the
317 * volume is not mounted, and not reserved, and not in use, it will be
318 * removed from the list.
320 * 5. If a job wants to reserve a drive with a different Volume from the one on
321 * the drive, it can re-use the drive for the new Volume.
323 * 6. If a job wants a Volume that is in a different drive, it can either use the
324 * other drive or take the volume, only if the other drive is not in use or
327 * One nice aspect of this is that the reserve use count and the writer use count
328 * already exist and are correctly programmed and will need no changes -- use
329 * counts are always very tricky.
331 * The old code had a concept of "reserving" a Volume, but was changed
332 * to reserving and using a drive. A volume is must be attached to (owned by) a
333 * drive and can move from drive to drive or be unused given certain specific
334 * conditions of the drive. The key is that the drive must "own" the Volume.
335 * The old code had the job (dcr) owning the volume (more or less). The job was
336 * to change the insertion and removal of the volumes from the list to be based
337 * on the drive rather than the job.
339 * Return: VOLRES entry on success
340 * NULL volume busy on another drive
342 VOLRES *reserve_volume(DCR *dcr, const char *VolumeName)
345 DEVICE * volatile dev = dcr->dev;
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 * Check if we are trying to use the Volume on a different drive
419 * vol->dev is where the Volume we want is
421 if (dev != vol->dev) {
422 /* Caller wants to switch Volume to another device */
423 if (!vol->dev->is_busy() && !vol->is_swapping()) {
425 Dmsg3(dbglvl, "==== Swap vol=%s from dev=%s to %s\n",
426 VolumeName, vol->dev->print_name(), dev->print_name());
427 free_volume(dev); /* free any volume attached to our drive */
428 Dmsg0(50, "set_unload\n");
429 dev->set_unload(); /* Unload any volume that is on our drive */
430 dcr->dev = vol->dev; /* temp point to other dev */
431 slot = get_autochanger_loaded_slot(dcr); /* get slot on other drive */
432 dcr->dev = dev; /* restore dev */
433 vol->set_slot(slot); /* save slot */
434 vol->dev->set_unload(); /* unload the other drive */
435 vol->set_swapping(); /* swap from other drive */
436 dev->swap_dev = vol->dev; /* remember to get this vol */
437 dev->set_load(); /* then reload on our drive */
438 vol->dev->vol = NULL; /* remove volume from other drive */
439 vol->dev = dev; /* point the Volume at our drive */
440 dev->vol = vol; /* point our drive at the Volume */
442 Dmsg3(dbglvl, "==== Swap not possible Vol busy vol=%s from dev=%s to %s\n",
443 VolumeName, vol->dev->print_name(), dev->print_name());
444 vol = NULL; /* device busy */
451 dev->vol = vol; /* point to newly inserted volume */
456 Dmsg2(dbglvl, "=== set in_use. vol=%s dev=%s\n", vol->vol_name,
457 vol->dev->print_name());
459 dcr->reserved_volume = true;
460 bstrncpy(dcr->VolumeName, vol->vol_name, sizeof(dcr->VolumeName));
462 debug_list_volumes("end new volume");
468 * Switch from current device to given device
472 void switch_device(DCR *dcr, DEVICE *dev)
477 memcpy(&save_dcr, dcr, sizeof(save_dcr));
478 clean_device(dcr); /* clean up the dcr */
480 dcr->dev = dev; /* get new device pointer */
481 Jmsg(dcr->jcr, M_INFO, 0, _("Device switch. New device %s chosen.\n"),
482 dcr->dev->print_name());
484 bstrncpy(dcr->VolumeName, save_dcr.VolumeName, sizeof(dcr->VolumeName));
485 bstrncpy(dcr->media_type, save_dcr.media_type, sizeof(dcr->media_type));
486 dcr->VolCatInfo.Slot = save_dcr.VolCatInfo.Slot;
487 bstrncpy(dcr->pool_name, save_dcr.pool_name, sizeof(dcr->pool_name));
488 bstrncpy(dcr->pool_type, save_dcr.pool_type, sizeof(dcr->pool_type));
489 bstrncpy(dcr->dev_name, dev->dev_name, sizeof(dcr->dev_name));
491 // dcr->set_reserved();
498 * Search for a Volume name in the Volume list.
500 * Returns: VOLRES entry on success
501 * NULL if the Volume is not in the list
503 VOLRES *find_volume(const char *VolumeName)
507 if (vol_list->empty()) {
510 /* Do not lock reservations here */
512 vol.vol_name = bstrdup(VolumeName);
513 fvol = (VOLRES *)vol_list->binary_search(&vol, my_compare);
515 Dmsg2(dbglvl, "find_vol=%s found=%d\n", VolumeName, fvol!=NULL);
516 debug_list_volumes("find_volume");
522 * Search for a Volume name in the read Volume list.
524 * Returns: VOLRES entry on success
525 * NULL if the Volume is not in the list
527 static VOLRES *find_read_volume(const char *VolumeName)
531 if (read_vol_list->empty()) {
532 Dmsg0(dbglvl, "find_read_vol: read_vol_list empty.\n");
535 /* Do not lock reservations here */
537 vol.vol_name = bstrdup(VolumeName);
538 /* Note, we do want a simple my_compare on volume name only here */
539 fvol = (VOLRES *)read_vol_list->binary_search(&vol, my_compare);
541 Dmsg2(dbglvl, "find_read_vol=%s found=%d\n", VolumeName, fvol!=NULL);
542 unlock_read_volumes();
548 * Free a Volume from the Volume list if it is no longer used
549 * Note, for tape drives we want to remember where the Volume
550 * was when last used, so rather than free the volume entry,
551 * we simply mark it "not reserved" so when the drive is really
552 * needed for another volume, we can reuse it.
554 * Returns: true if the Volume found and "removed" from the list
555 * false if the Volume is not in the list or is in use
557 bool volume_unused(DCR *dcr)
559 DEVICE *dev = dcr->dev;
562 Dmsg1(dbglvl, "vol_unused: no vol on %s\n", dev->print_name());
563 debug_list_volumes("null vol cannot unreserve_volume");
566 if (dev->vol->is_swapping()) {
567 Dmsg1(dbglvl, "vol_unused: vol being swapped on %s\n", dev->print_name());
568 Dmsg1(dbglvl, "=== clear in_use vol=%s\n", dev->vol->vol_name);
569 dev->vol->clear_in_use();
570 debug_list_volumes("swapping vol cannot free_volume");
575 * If this is a tape, we do not free the volume, rather we wait
576 * until the autoloader unloads it, or until another tape is
577 * explicitly read in this drive. This allows the SD to remember
578 * where the tapes are or last were.
580 Dmsg4(dbglvl, "=== set not reserved vol=%s num_writers=%d dev_reserved=%d dev=%s\n",
581 dev->vol->vol_name, dev->num_writers, dev->num_reserved(), dev->print_name());
582 Dmsg1(dbglvl, "=== clear in_use vol=%s\n", dev->vol->vol_name);
583 dev->vol->clear_in_use();
584 if (dev->is_tape() || dev->is_autochanger()) {
588 * Note, this frees the volume reservation entry, but the
589 * file descriptor remains open with the OS.
591 return free_volume(dev);
596 * Unconditionally release the volume entry
598 bool free_volume(DEVICE *dev)
602 if (dev->vol == NULL) {
603 Dmsg1(dbglvl, "No vol on dev %s\n", dev->print_name());
608 /* Don't free a volume while it is being swapped */
609 if (!vol->is_swapping()) {
610 Dmsg1(dbglvl, "=== clear in_use vol=%s\n", dev->vol->vol_name);
612 vol_list->remove(vol);
613 Dmsg2(dbglvl, "=== remove volume %s dev=%s\n", vol->vol_name, dev->print_name());
615 debug_list_volumes("free_volume");
622 /* Create the Volume list */
623 void create_volume_lists()
626 if (vol_list == NULL) {
627 vol_list = New(dlist(vol, &vol->link));
629 if (read_vol_list == NULL) {
630 read_vol_list = New(dlist(vol, &vol->link));
635 * Free normal append volumes list
637 static void free_volume_list()
642 foreach_dlist(vol, vol_list) {
644 Dmsg2(dbglvl, "free vol_list Volume=%s dev=%s\n", vol->vol_name, vol->dev->print_name());
646 Dmsg1(dbglvl, "free vol_list Volume=%s No dev\n", vol->vol_name);
649 vol->vol_name = NULL;
657 /* Release all Volumes from the list */
658 void free_volume_lists()
662 free_volume_list(); /* normal append list */
666 foreach_dlist(vol, read_vol_list) {
668 Dmsg2(dbglvl, "free read_vol_list Volume=%s dev=%s\n", vol->vol_name, vol->dev->print_name());
670 Dmsg1(dbglvl, "free read_vol_list Volume=%s No dev\n", vol->vol_name);
673 vol->vol_name = NULL;
675 delete read_vol_list;
676 read_vol_list = NULL;
677 unlock_read_volumes();
682 * Determine if caller can write on volume
684 bool DCR::can_i_write_volume()
688 vol = find_read_volume(VolumeName);
690 Dmsg1(100, "Found in read list; cannot write vol=%s\n", VolumeName);
693 return can_i_use_volume();
697 * Determine if caller can read or write volume
699 bool DCR::can_i_use_volume()
705 vol = find_volume(VolumeName);
707 Dmsg1(dbglvl, "Vol=%s not in use.\n", VolumeName);
708 goto get_out; /* vol not in list */
710 ASSERT(vol->dev != NULL);
712 if (dev == vol->dev) { /* same device OK */
713 Dmsg1(dbglvl, "Vol=%s on same dev.\n", VolumeName);
716 Dmsg3(dbglvl, "Vol=%s on %s we have %s\n", VolumeName,
717 vol->dev->print_name(), dev->print_name());
719 /* ***FIXME*** check this ... */
720 if (!vol->dev->is_busy()) {
721 Dmsg2(dbglvl, "Vol=%s dev=%s not busy.\n", VolumeName, vol->dev->print_name());
724 Dmsg2(dbglvl, "Vol=%s dev=%s busy.\n", VolumeName, vol->dev->print_name());
726 Dmsg2(dbglvl, "Vol=%s in use by %s.\n", VolumeName, vol->dev->print_name());
736 * Create a temporary copy of the volume list. We do this,
737 * to avoid having the volume list locked during the
738 * call to reserve_device(), which would cause a deadlock.
739 * Note, we may want to add an update counter on the vol_list
740 * so that if it is modified while we are traversing the copy
741 * we can take note and act accordingly (probably redo the
742 * search at least a few times).
744 dlist *dup_vol_list(JCR *jcr)
746 dlist *temp_vol_list;
750 Dmsg0(dbglvl, "lock volumes\n");
752 Dmsg0(dbglvl, "duplicate vol list\n");
753 temp_vol_list = New(dlist(vol, &vol->link));
754 foreach_dlist(vol, vol_list) {
756 VOLRES *tvol = (VOLRES *)malloc(sizeof(VOLRES));
757 memset(tvol, 0, sizeof(VOLRES));
758 tvol->vol_name = bstrdup(vol->vol_name);
759 tvol->dev = vol->dev;
760 nvol = (VOLRES *)temp_vol_list->binary_insert(tvol, my_compare);
762 tvol->dev = NULL; /* don't zap dev entry */
764 Pmsg0(000, "Logic error. Duplicating vol list hit duplicate.\n");
765 Jmsg(jcr, M_WARNING, 0, "Logic error. Duplicating vol list hit duplicate.\n");
768 Dmsg0(dbglvl, "unlock volumes\n");
770 return temp_vol_list;
774 * Free the specified temp list.
776 void free_temp_vol_list(dlist *temp_vol_list)
778 dlist *save_vol_list;
781 save_vol_list = vol_list;
782 vol_list = temp_vol_list;
783 free_volume_list(); /* release temp_vol_list */
784 vol_list = save_vol_list;
785 Dmsg0(dbglvl, "deleted temp vol list\n");
786 Dmsg0(dbglvl, "unlock volumes\n");
788 debug_list_volumes("after free temp table");