3 * Higher Level Device routines.
4 * Knows about Bacula tape labels and such
6 * NOTE! In general, subroutines that have the word
7 * "device" in the name do locking. Subroutines
8 * that have the word "dev" in the name do not
9 * do locking. Thus if xxx_device() calls
10 * yyy_dev(), all is OK, but if xxx_device()
11 * calls yyy_device(), everything will hang.
12 * Obviously, no zzz_dev() is allowed to call
13 * a www_device() or everything falls apart.
15 * Concerning the routines lock_device() and block_device()
16 * see the end of this module for details. In general,
17 * blocking a device leaves it in a state where all threads
18 * other than the current thread block when they attempt to
19 * lock the device. They remain suspended (blocked) until the device
20 * is unblocked. So, a device is blocked during an operation
21 * that takes a long time (initialization, mounting a new
22 * volume, ...) locking a device is done for an operation
23 * that takes a short time such as writing data to the
27 * Kern Sibbald, MM, MMI
32 Copyright (C) 2000-2005 Kern Sibbald
34 This program is free software; you can redistribute it and/or
35 modify it under the terms of the GNU General Public License
36 version 2 as amended with additional clauses defined in the
37 file LICENSE in the main source directory.
39 This program is distributed in the hope that it will be useful,
40 but WITHOUT ANY WARRANTY; without even the implied warranty of
41 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
42 the file LICENSE for additional details.
46 #include "bacula.h" /* pull in global headers */
47 #include "stored.h" /* pull in Storage Deamon headers */
49 /* Forward referenced functions */
51 extern char my_name[];
52 extern int debug_level;
55 * This is the dreaded moment. We either have an end of
56 * medium condition or worse, and error condition.
57 * Attempt to "recover" by obtaining a new Volume.
59 * Here are a few things to know:
60 * dcr->VolCatInfo contains the info on the "current" tape for this job.
61 * dev->VolCatInfo contains the info on the tape in the drive.
62 * The tape in the drive could have changed several times since
63 * the last time the job used it (jcr->VolCatInfo).
64 * dcr->VolumeName is the name of the current/desired tape in the drive.
66 * We enter with device locked, and
67 * exit with device locked.
69 * Note, we are called only from one place in block.c
71 * Returns: true on success
74 bool fixup_device_block_write_error(DCR *dcr)
76 char PrevVolName[MAX_NAME_LENGTH];
78 DEV_BLOCK *block = dcr->block;
81 char dt[MAX_TIME_LENGTH];
83 DEVICE *dev = dcr->dev;
85 wait_time = time(NULL);
87 Dmsg0(100, "Enter fixup_device_block_write_error\n");
89 block_device(dev, BST_DOING_ACQUIRE);
90 /* Unlock, but leave BLOCKED */
93 bstrncpy(PrevVolName, dev->VolCatInfo.VolCatName, sizeof(PrevVolName));
94 bstrncpy(dev->VolHdr.PrevVolumeName, PrevVolName, sizeof(dev->VolHdr.PrevVolumeName));
96 label_blk = new_block(dev);
97 dcr->block = label_blk;
99 /* Inform User about end of medium */
100 Jmsg(jcr, M_INFO, 0, _("End of medium on Volume \"%s\" Bytes=%s Blocks=%s at %s.\n"),
101 PrevVolName, edit_uint64_with_commas(dev->VolCatInfo.VolCatBytes, b1),
102 edit_uint64_with_commas(dev->VolCatInfo.VolCatBlocks, b2),
103 bstrftime(dt, sizeof(dt), time(NULL)));
105 if (!mount_next_write_volume(dcr, 1)) {
106 free_block(label_blk);
110 return false; /* device locked */
112 P(dev->mutex); /* lock again */
114 Jmsg(jcr, M_INFO, 0, _("New volume \"%s\" mounted on device %s at %s.\n"),
115 dcr->VolumeName, dev->print_name(), bstrftime(dt, sizeof(dt), time(NULL)));
118 * If this is a new tape, the label_blk will contain the
119 * label, so write it now. If this is a previously
120 * used tape, mount_next_write_volume() will return an
121 * empty label_blk, and nothing will be written.
123 Dmsg0(190, "write label block to dev\n");
124 if (!write_block_to_dev(dcr)) {
126 Pmsg1(0, _("write_block_to_device Volume label failed. ERR=%s"),
127 be.strerror(dev->dev_errno));
128 free_block(label_blk);
131 return false; /* device locked */
133 free_block(label_blk);
137 * Walk through all attached jcrs indicating the volume has changed
139 Dmsg1(100, "Walk attached dcrs. Volume=%s\n", dev->VolCatInfo.VolCatName);
141 foreach_dlist(mdcr, dev->attached_dcrs) {
142 JCR *mjcr = mdcr->jcr;
143 if (mjcr->JobId == 0) {
144 continue; /* ignore console */
148 bstrncpy(mdcr->VolumeName, dcr->VolumeName, sizeof(mdcr->VolumeName));
152 /* Clear NewVol now because dir_get_volume_info() already done */
153 jcr->dcr->NewVol = false;
154 set_new_volume_parameters(dcr);
156 jcr->run_time += time(NULL) - wait_time; /* correct run time for mount wait */
158 /* Write overflow block to device */
159 Dmsg0(190, "Write overflow block to dev\n");
160 if (!write_block_to_dev(dcr)) {
162 Pmsg1(0, _("write_block_to_device overflow block failed. ERR=%s"),
163 be.strerror(dev->dev_errno));
165 return false; /* device locked */
169 return true; /* device locked */
173 * We have a new Volume mounted, so reset the Volume parameters
174 * concerning this job. The global changes were made earlier
175 * in the dev structure.
177 void set_new_volume_parameters(DCR *dcr)
180 DEVICE *dev = dcr->dev;
181 if (dcr->NewVol && !dir_get_volume_info(dcr, GET_VOL_INFO_FOR_WRITE)) {
182 Jmsg1(jcr, M_ERROR, 0, "%s", jcr->errmsg);
184 /* Set new start/end positions */
185 if (dev->is_tape()) {
186 dcr->StartBlock = dev->block_num;
187 dcr->StartFile = dev->file;
189 dcr->StartBlock = (uint32_t)dev->file_addr;
190 dcr->StartFile = (uint32_t)(dev->file_addr >> 32);
193 dcr->VolFirstIndex = 0;
194 dcr->VolLastIndex = 0;
197 dcr->WroteVol = false;
201 * We are now in a new Volume file, so reset the Volume parameters
202 * concerning this job. The global changes were made earlier
203 * in the dev structure.
205 void set_new_file_parameters(DCR *dcr)
207 DEVICE *dev = dcr->dev;
209 /* Set new start/end positions */
210 if (dev->is_tape()) {
211 dcr->StartBlock = dev->block_num;
212 dcr->StartFile = dev->file;
214 dcr->StartBlock = (uint32_t)dev->file_addr;
215 dcr->StartFile = (uint32_t)(dev->file_addr >> 32);
218 dcr->VolFirstIndex = 0;
219 dcr->VolLastIndex = 0;
220 dcr->NewFile = false;
221 dcr->WroteVol = false;
227 * First Open of the device. Expect dev to already be initialized.
229 * This routine is used only when the Storage daemon starts
230 * and always_open is set, and in the stand-alone utility
231 * routines such as bextract.
233 * Note, opening of a normal file is deferred to later so
234 * that we can get the filename; the device_name for
235 * a file is the directory only.
237 * Returns: false on failure
240 bool first_open_device(DCR *dcr)
242 DEVICE *dev = dcr->dev;
245 Dmsg0(120, "start open_output_device()\n");
252 /* Defer opening files */
253 if (!dev->is_tape()) {
254 Dmsg0(129, "Device is file, deferring open.\n");
259 if (dev_cap(dev, CAP_STREAM)) {
260 mode = OPEN_WRITE_ONLY;
262 mode = OPEN_READ_ONLY;
264 Dmsg0(129, "Opening device.\n");
265 if (dev->open(dcr, mode) < 0) {
266 Emsg1(M_FATAL, 0, _("dev open failed: %s\n"), dev->errmsg);
270 Dmsg1(129, "open dev %s OK\n", dev->print_name());
278 * Make sure device is open, if not do so
280 bool open_device(DCR *dcr)
282 DEVICE *dev = dcr->dev;
285 if (dev_cap(dev, CAP_STREAM)) {
286 mode = OPEN_WRITE_ONLY;
288 mode = OPEN_READ_WRITE;
290 if (dev->open(dcr, mode) < 0) {
291 /* If polling, ignore the error */
292 /* If DVD, also ignore the error, very often you cannot open the device
293 * (when there is no DVD, or when the one inserted is a wrong one) */
294 if (!dev->poll && !dev->is_dvd() && !dev->is_removable()) {
295 Jmsg2(dcr->jcr, M_FATAL, 0, _("Unable to open device %s: ERR=%s\n"),
296 dev->print_name(), dev->bstrerror());
297 Pmsg2(000, _("Unable to open archive %s: ERR=%s\n"),
298 dev->print_name(), dev->bstrerror());
307 void dev_lock(DEVICE *dev)
310 if ((errstat=rwl_writelock(&dev->lock))) {
311 Emsg1(M_ABORT, 0, _("Device write lock failure. ERR=%s\n"), strerror(errstat));
315 void dev_unlock(DEVICE *dev)
318 if ((errstat=rwl_writeunlock(&dev->lock))) {
319 Emsg1(M_ABORT, 0, _("Device write unlock failure. ERR=%s\n"), strerror(errstat));
324 * When dev_blocked is set, all threads EXCEPT thread with id no_wait_id
325 * must wait. The no_wait_id thread is out obtaining a new volume
326 * and preparing the label.
328 void _lock_device(const char *file, int line, DEVICE *dev)
331 Dmsg3(500, "lock %d from %s:%d\n", dev->dev_blocked, file, line);
333 if (dev->dev_blocked && !pthread_equal(dev->no_wait_id, pthread_self())) {
334 dev->num_waiting++; /* indicate that I am waiting */
335 while (dev->dev_blocked) {
336 if ((stat = pthread_cond_wait(&dev->wait, &dev->mutex)) != 0) {
338 Emsg1(M_ABORT, 0, _("pthread_cond_wait failure. ERR=%s\n"),
342 dev->num_waiting--; /* no longer waiting */
347 * Check if the device is blocked or not
349 bool is_device_unmounted(DEVICE *dev)
352 int blocked = dev->dev_blocked;
353 stat = (blocked == BST_UNMOUNTED) ||
354 (blocked == BST_UNMOUNTED_WAITING_FOR_SYSOP);
358 void _unlock_device(const char *file, int line, DEVICE *dev)
360 Dmsg2(500, "unlock from %s:%d\n", file, line);
365 * Block all other threads from using the device
366 * Device must already be locked. After this call,
367 * the device is blocked to any thread calling lock_device(),
368 * but the device is not locked (i.e. no P on device). Also,
369 * the current thread can do slip through the lock_device()
370 * calls without blocking.
372 void _block_device(const char *file, int line, DEVICE *dev, int state)
374 Dmsg3(500, "block set %d from %s:%d\n", state, file, line);
375 ASSERT(dev->get_blocked() == BST_NOT_BLOCKED);
376 dev->set_blocked(state); /* make other threads wait */
377 dev->no_wait_id = pthread_self(); /* allow us to continue */
383 * Unblock the device, and wake up anyone who went to sleep.
385 void _unblock_device(const char *file, int line, DEVICE *dev)
387 Dmsg3(500, "unblock %s from %s:%d\n", dev->print_blocked(), file, line);
388 ASSERT(dev->dev_blocked);
389 dev->set_blocked(BST_NOT_BLOCKED);
391 if (dev->num_waiting > 0) {
392 pthread_cond_broadcast(&dev->wait); /* wake them up */
397 * Enter with device locked and blocked
398 * Exit with device unlocked and blocked by us.
400 void _steal_device_lock(const char *file, int line, DEVICE *dev, bsteal_lock_t *hold, int state)
403 Dmsg3(400, "steal lock. old=%s from %s:%d\n", dev->print_blocked(),
405 hold->dev_blocked = dev->get_blocked();
406 hold->dev_prev_blocked = dev->dev_prev_blocked;
407 hold->no_wait_id = dev->no_wait_id;
408 dev->set_blocked(state);
409 Dmsg1(400, "steal lock. new=%s\n", dev->print_blocked());
410 dev->no_wait_id = pthread_self();
415 * Enter with device blocked by us but not locked
416 * Exit with device locked, and blocked by previous owner
418 void _give_back_device_lock(const char *file, int line, DEVICE *dev, bsteal_lock_t *hold)
420 Dmsg3(400, "return lock. old=%s from %s:%d\n",
421 dev->print_blocked(), file, line);
423 dev->dev_blocked = hold->dev_blocked;
424 dev->dev_prev_blocked = hold->dev_prev_blocked;
425 dev->no_wait_id = hold->no_wait_id;
426 Dmsg1(400, "return lock. new=%s\n", dev->print_blocked());
427 if (dev->num_waiting > 0) {
428 pthread_cond_broadcast(&dev->wait); /* wake them up */