2 Bacula® - The Network Backup Solution
4 Copyright (C) 2000-2008 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 = 50;
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(1, "read_vol=%s JobId=%d already in list.\n", VolumeName, jcr->JobId);
163 Dmsg2(1, "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);
179 Dmsg3(1, "remove_read_vol=%s JobId=%d found=%d\n", VolumeName, jcr->JobId, fvol!=NULL);
180 debug_list_volumes("remove_read_volume");
182 read_vol_list->remove(fvol);
185 unlock_read_volumes();
189 * List Volumes -- this should be moved to status.c
196 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;
347 Dmsg2(dbglvl, "enter reserve_volume=%s drive=%s\n", VolumeName,
348 dcr->dev->print_name());
350 * We lock the reservations system here to ensure
351 * when adding a new volume that no newly scheduled
352 * job can reserve it.
355 debug_list_volumes("begin reserve_volume");
357 * First, remove any old volume attached to this device as it
362 Dmsg4(dbglvl, "Vol attached=%s, newvol=%s volinuse=%d on %s\n",
363 vol->vol_name, VolumeName, vol->is_in_use(), dev->print_name());
365 * Make sure we don't remove the current volume we are inserting
366 * because it was probably inserted by another job, or it
367 * is not being used and is marked as not reserved.
369 if (strcmp(vol->vol_name, VolumeName) == 0) {
370 Dmsg2(dbglvl, "=== set reserved vol=%s dev=%s\n", VolumeName,
371 vol->dev->print_name());
372 goto get_out; /* Volume already on this device */
374 /* Don't release a volume if it was reserved by someone other than us */
375 if (vol->is_in_use() && !dcr->reserved_volume) {
376 Dmsg1(dbglvl, "Cannot free vol=%s. It is reserved.\n", vol->vol_name);
377 vol = NULL; /* vol in use */
380 Dmsg2(dbglvl, "reserve_vol free vol=%s at %p\n", vol->vol_name, vol->vol_name);
382 Dmsg0(50, "set_unload\n");
383 dev->set_unload(); /* have to unload current volume */
384 debug_list_volumes("reserve_vol free");
388 /* Create a new Volume entry */
389 nvol = new_vol_item(dcr, VolumeName);
392 * Now try to insert the new Volume
394 vol = (VOLRES *)vol_list->binary_insert(nvol, my_compare);
396 Dmsg2(dbglvl, "Found vol=%s dev-same=%d\n", vol->vol_name, dev==vol->dev);
398 * At this point, a Volume with this name already is in the list,
399 * so we simply release our new Volume entry. Note, this should
400 * only happen if we are moving the volume from one drive to another.
402 Dmsg2(dbglvl, "reserve_vol free-tmp vol=%s at %p\n",
403 vol->vol_name, vol->vol_name);
405 * Clear dev pointer so that free_vol_item() doesn't
406 * take away our volume.
408 nvol->dev = NULL; /* don't zap dev entry */
412 * Check if we are trying to use the Volume on a different drive
414 * vol->dev is where the Volume we want is
416 if (dev != vol->dev) {
417 /* Caller wants to switch Volume to another device */
418 if (!vol->dev->is_busy() && !vol->is_swapping()) {
420 Dmsg3(dbglvl, "==== Swap vol=%s from dev=%s to %s\n",
421 VolumeName, vol->dev->print_name(), dev->print_name());
422 free_volume(dev); /* free any volume attached to our drive */
423 Dmsg0(50, "set_unload\n");
424 dev->set_unload(); /* Unload any volume that is on our drive */
425 dcr->dev = vol->dev; /* temp point to other dev */
426 slot = get_autochanger_loaded_slot(dcr); /* get slot on other drive */
427 dcr->dev = dev; /* restore dev */
428 vol->set_slot(slot); /* save slot */
429 vol->dev->set_unload(); /* unload the other drive */
430 vol->set_swapping(); /* swap from other drive */
431 dev->swap_dev = vol->dev; /* remember to get this vol */
432 dev->set_load(); /* then reload on our drive */
433 vol->dev->vol = NULL; /* remove volume from other drive */
434 vol->dev = dev; /* point the Volume at our drive */
435 dev->vol = vol; /* point our drive at the Volume */
437 Dmsg3(dbglvl, "==== Swap not possible Vol busy vol=%s from dev=%s to %s\n",
438 VolumeName, vol->dev->print_name(), dev->print_name());
439 vol = NULL; /* device busy */
446 dev->vol = vol; /* point to newly inserted volume */
451 Dmsg2(dbglvl, "=== set in_use. vol=%s dev=%s\n", vol->vol_name,
452 vol->dev->print_name());
454 dcr->reserved_volume = true;
455 bstrncpy(dcr->VolumeName, vol->vol_name, sizeof(dcr->VolumeName));
457 debug_list_volumes("end new volume");
463 * Switch from current device to given device
467 void switch_device(DCR *dcr, DEVICE *dev)
472 memcpy(&save_dcr, dcr, sizeof(save_dcr));
473 clean_device(dcr); /* clean up the dcr */
475 dcr->dev = dev; /* get new device pointer */
476 Jmsg(dcr->jcr, M_INFO, 0, _("Device switch. New device %s chosen.\n"),
477 dcr->dev->print_name());
479 bstrncpy(dcr->VolumeName, save_dcr.VolumeName, sizeof(dcr->VolumeName));
480 bstrncpy(dcr->media_type, save_dcr.media_type, sizeof(dcr->media_type));
481 dcr->VolCatInfo.Slot = save_dcr.VolCatInfo.Slot;
482 bstrncpy(dcr->pool_name, save_dcr.pool_name, sizeof(dcr->pool_name));
483 bstrncpy(dcr->pool_type, save_dcr.pool_type, sizeof(dcr->pool_type));
484 bstrncpy(dcr->dev_name, dev->dev_name, sizeof(dcr->dev_name));
486 // dcr->set_reserved();
493 * Search for a Volume name in the Volume list.
495 * Returns: VOLRES entry on success
496 * NULL if the Volume is not in the list
498 VOLRES *find_volume(const char *VolumeName)
502 if (vol_list->empty()) {
505 /* Do not lock reservations here */
507 vol.vol_name = bstrdup(VolumeName);
508 fvol = (VOLRES *)vol_list->binary_search(&vol, my_compare);
510 Dmsg2(dbglvl, "find_vol=%s found=%d\n", VolumeName, fvol!=NULL);
511 debug_list_volumes("find_volume");
517 * Search for a Volume name in the read Volume list.
519 * Returns: VOLRES entry on success
520 * NULL if the Volume is not in the list
522 static VOLRES *find_read_volume(const char *VolumeName)
526 if (read_vol_list->empty()) {
529 /* Do not lock reservations here */
531 vol.vol_name = bstrdup(VolumeName);
532 /* Note, we do want a simple my_compare on volume name only here */
533 fvol = (VOLRES *)read_vol_list->binary_search(&vol, my_compare);
535 Dmsg2(dbglvl, "find_read_vol=%s found=%d\n", VolumeName, fvol!=NULL);
536 unlock_read_volumes();
542 * Free a Volume from the Volume list if it is no longer used
543 * Note, for tape drives we want to remember where the Volume
544 * was when last used, so rather than free the volume entry,
545 * we simply mark it "not reserved" so when the drive is really
546 * needed for another volume, we can reuse it.
548 * Returns: true if the Volume found and "removed" from the list
549 * false if the Volume is not in the list or is in use
551 bool volume_unused(DCR *dcr)
553 DEVICE *dev = dcr->dev;
556 Dmsg1(dbglvl, "vol_unused: no vol on %s\n", dev->print_name());
557 debug_list_volumes("null vol cannot unreserve_volume");
560 if (dev->vol->is_swapping()) {
561 Dmsg1(dbglvl, "vol_unused: vol being swapped on %s\n", dev->print_name());
562 Dmsg1(dbglvl, "=== clear in_use vol=%s\n", dev->vol->vol_name);
563 dev->vol->clear_in_use();
564 debug_list_volumes("swapping vol cannot free_volume");
569 * If this is a tape, we do not free the volume, rather we wait
570 * until the autoloader unloads it, or until another tape is
571 * explicitly read in this drive. This allows the SD to remember
572 * where the tapes are or last were.
574 Dmsg4(dbglvl, "=== set not reserved vol=%s num_writers=%d dev_reserved=%d dev=%s\n",
575 dev->vol->vol_name, dev->num_writers, dev->num_reserved(), dev->print_name());
576 Dmsg1(dbglvl, "=== clear in_use vol=%s\n", dev->vol->vol_name);
577 dev->vol->clear_in_use();
578 if (dev->is_tape() || dev->is_autochanger()) {
582 * Note, this frees the volume reservation entry, but the
583 * file descriptor remains open with the OS.
585 return free_volume(dev);
590 * Unconditionally release the volume entry
592 bool free_volume(DEVICE *dev)
596 if (dev->vol == NULL) {
597 Dmsg1(dbglvl, "No vol on dev %s\n", dev->print_name());
602 /* Don't free a volume while it is being swapped */
603 if (!vol->is_swapping()) {
604 Dmsg1(dbglvl, "=== clear in_use vol=%s\n", dev->vol->vol_name);
606 vol_list->remove(vol);
607 Dmsg2(dbglvl, "=== remove volume %s dev=%s\n", vol->vol_name, dev->print_name());
609 debug_list_volumes("free_volume");
616 /* Create the Volume list */
617 void create_volume_lists()
620 if (vol_list == NULL) {
621 vol_list = New(dlist(vol, &vol->link));
623 if (read_vol_list == NULL) {
624 read_vol_list = New(dlist(vol, &vol->link));
629 * Free normal append volumes list
631 static void free_volume_list()
636 foreach_dlist(vol, vol_list) {
638 Dmsg2(dbglvl, "free vol_list Volume=%s dev=%s\n", vol->vol_name, vol->dev->print_name());
640 Dmsg1(dbglvl, "free vol_list Volume=%s No dev\n", vol->vol_name);
643 vol->vol_name = NULL;
651 /* Release all Volumes from the list */
652 void free_volume_lists()
656 free_volume_list(); /* normal append list */
660 foreach_dlist(vol, read_vol_list) {
662 Dmsg2(dbglvl, "free read_vol_list Volume=%s dev=%s\n", vol->vol_name, vol->dev->print_name());
664 Dmsg1(dbglvl, "free read_vol_list Volume=%s No dev\n", vol->vol_name);
667 vol->vol_name = NULL;
669 delete read_vol_list;
670 read_vol_list = NULL;
671 unlock_read_volumes();
676 * Determine if caller can write on volume
678 bool DCR::can_i_write_volume()
683 vol = find_read_volume(VolumeName);
684 unlock_read_volumes();
686 Dmsg1(100, "Found in read list; cannot write vol=%s\n", VolumeName);
689 return can_i_use_volume();
693 * Determine if caller can read or write volume
695 bool DCR::can_i_use_volume()
701 vol = find_volume(VolumeName);
703 Dmsg1(dbglvl, "Vol=%s not in use.\n", VolumeName);
704 goto get_out; /* vol not in list */
706 ASSERT(vol->dev != NULL);
708 if (dev == vol->dev) { /* same device OK */
709 Dmsg1(dbglvl, "Vol=%s on same dev.\n", VolumeName);
712 Dmsg3(dbglvl, "Vol=%s on %s we have %s\n", VolumeName,
713 vol->dev->print_name(), dev->print_name());
715 /* ***FIXME*** check this ... */
716 if (!vol->dev->is_busy()) {
717 Dmsg2(dbglvl, "Vol=%s dev=%s not busy.\n", VolumeName, vol->dev->print_name());
720 Dmsg2(dbglvl, "Vol=%s dev=%s busy.\n", VolumeName, vol->dev->print_name());
722 Dmsg2(dbglvl, "Vol=%s in use by %s.\n", VolumeName, vol->dev->print_name());
732 * Create a temporary copy of the volume list. We do this,
733 * to avoid having the volume list locked during the
734 * call to reserve_device(), which would cause a deadlock.
735 * Note, we may want to add an update counter on the vol_list
736 * so that if it is modified while we are traversing the copy
737 * we can take note and act accordingly (probably redo the
738 * search at least a few times).
740 dlist *dup_vol_list(JCR *jcr)
742 dlist *temp_vol_list;
746 Dmsg0(dbglvl, "lock volumes\n");
748 Dmsg0(dbglvl, "duplicate vol list\n");
749 temp_vol_list = New(dlist(vol, &vol->link));
750 foreach_dlist(vol, vol_list) {
752 VOLRES *tvol = (VOLRES *)malloc(sizeof(VOLRES));
753 memset(tvol, 0, sizeof(VOLRES));
754 tvol->vol_name = bstrdup(vol->vol_name);
755 tvol->dev = vol->dev;
756 nvol = (VOLRES *)temp_vol_list->binary_insert(tvol, my_compare);
758 tvol->dev = NULL; /* don't zap dev entry */
760 Pmsg0(000, "Logic error. Duplicating vol list hit duplicate.\n");
761 Jmsg(jcr, M_WARNING, 0, "Logic error. Duplicating vol list hit duplicate.\n");
764 Dmsg0(dbglvl, "unlock volumes\n");
766 return temp_vol_list;
770 * Free the specified temp list.
772 void free_temp_vol_list(dlist *temp_vol_list)
774 dlist *save_vol_list;
777 save_vol_list = vol_list;
778 vol_list = temp_vol_list;
779 free_volume_list(); /* release temp_vol_list */
780 vol_list = save_vol_list;
781 Dmsg0(dbglvl, "deleted temp vol list\n");
782 Dmsg0(dbglvl, "unlock volumes\n");
784 debug_list_volumes("after free temp table");