3 * block.c -- tape block handling functions
5 * Kern Sibbald, March MMI
6 * added BB02 format October MMII
12 Copyright (C) 2000-2003 Kern Sibbald and John Walker
14 This program is free software; you can redistribute it and/or
15 modify it under the terms of the GNU General Public License as
16 published by the Free Software Foundation; either version 2 of
17 the License, or (at your option) any later version.
19 This program is distributed in the hope that it will be useful,
20 but WITHOUT ANY WARRANTY; without even the implied warranty of
21 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
22 General Public License for more details.
24 You should have received a copy of the GNU General Public
25 License along with this program; if not, write to the Free
26 Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
35 extern int debug_level;
38 * Dump the block header, then walk through
39 * the block printing out the record headers.
41 void dump_block(DEV_BLOCK *b, char *msg)
45 char Id[BLKHDR_ID_LENGTH+1];
46 uint32_t CheckSum, BlockCheckSum;
49 uint32_t VolSessionId, VolSessionTime, data_len;
54 unser_begin(b->buf, BLKHDR1_LENGTH);
55 unser_uint32(CheckSum);
56 unser_uint32(block_len);
57 unser_uint32(BlockNumber);
58 unser_bytes(Id, BLKHDR_ID_LENGTH);
59 ASSERT(unser_length(b->buf) == BLKHDR1_LENGTH);
60 Id[BLKHDR_ID_LENGTH] = 0;
62 unser_uint32(VolSessionId);
63 unser_uint32(VolSessionTime);
67 VolSessionId = VolSessionTime = 0;
72 if (block_len > 100000) {
73 Dmsg3(20, "Dump block %s 0x%x blocksize too big %u\n", msg, b, block_len);
77 BlockCheckSum = bcrc32((uint8_t *)b->buf+BLKHDR_CS_LENGTH,
78 block_len-BLKHDR_CS_LENGTH);
79 Pmsg6(000, "Dump block %s %x: size=%d BlkNum=%d\n\
80 Hdrcksum=%x cksum=%x\n",
81 msg, b, block_len, BlockNumber, CheckSum, BlockCheckSum);
83 while (p < (b->buf + block_len+WRITE_RECHDR_LENGTH)) {
84 unser_begin(p, WRITE_RECHDR_LENGTH);
85 if (rhl == RECHDR1_LENGTH) {
86 unser_uint32(VolSessionId);
87 unser_uint32(VolSessionTime);
89 unser_int32(FileIndex);
91 unser_uint32(data_len);
92 Pmsg6(000, " Rec: VId=%u VT=%u FI=%s Strm=%s len=%d p=%x\n",
93 VolSessionId, VolSessionTime, FI_to_ascii(FileIndex),
94 stream_to_ascii(Stream, FileIndex), data_len, p);
100 * Create a new block structure.
101 * We pass device so that the block can inherit the
102 * min and max block sizes.
104 DEV_BLOCK *new_block(DEVICE *dev)
106 DEV_BLOCK *block = (DEV_BLOCK *)get_memory(sizeof(DEV_BLOCK));
108 memset(block, 0, sizeof(DEV_BLOCK));
110 /* If the user has specified a max_block_size, use it as the default */
111 if (dev->max_block_size == 0) {
112 block->buf_len = DEFAULT_BLOCK_SIZE;
114 block->buf_len = dev->max_block_size;
117 block->block_len = block->buf_len; /* default block size */
118 block->buf = get_memory(block->buf_len);
119 if (block->buf == NULL) {
120 Mmsg0(&dev->errmsg, _("Unable to malloc block buffer.\n"));
121 Emsg0(M_FATAL, 0, dev->errmsg);
125 block->BlockVer = BLOCK_VER; /* default write version */
126 Dmsg1(90, "Returning new block=%x\n", block);
133 void free_block(DEV_BLOCK *block)
135 Dmsg1(199, "free_block buffer %x\n", block->buf);
136 free_memory(block->buf);
137 Dmsg1(199, "free_block block %x\n", block);
138 free_memory((POOLMEM *)block);
141 /* Empty the block -- for writing */
142 void empty_block(DEV_BLOCK *block)
144 block->binbuf = WRITE_BLKHDR_LENGTH;
145 block->bufp = block->buf + block->binbuf;
147 block->write_failed = false;
148 block->block_read = false;
149 block->FirstIndex = block->LastIndex = 0;
153 * Create block header just before write. The space
154 * in the buffer should have already been reserved by
157 static void ser_block_header(DEV_BLOCK *block)
160 uint32_t CheckSum = 0;
161 uint32_t block_len = block->binbuf;
163 Dmsg1(190, "ser_block_header: block_len=%d\n", block_len);
164 ser_begin(block->buf, BLKHDR2_LENGTH);
165 ser_uint32(CheckSum);
166 ser_uint32(block_len);
167 ser_uint32(block->BlockNumber);
168 ser_bytes(WRITE_BLKHDR_ID, BLKHDR_ID_LENGTH);
169 if (BLOCK_VER >= 2) {
170 ser_uint32(block->VolSessionId);
171 ser_uint32(block->VolSessionTime);
174 /* Checksum whole block except for the checksum */
175 CheckSum = bcrc32((uint8_t *)block->buf+BLKHDR_CS_LENGTH,
176 block_len-BLKHDR_CS_LENGTH);
177 Dmsg1(190, "ser_bloc_header: checksum=%x\n", CheckSum);
178 ser_begin(block->buf, BLKHDR2_LENGTH);
179 ser_uint32(CheckSum); /* now add checksum to block header */
183 * Unserialized the block header for reading block.
184 * This includes setting all the buffer pointers correctly.
186 * Returns: 0 on failure (not a block)
189 static int unser_block_header(DEVICE *dev, DEV_BLOCK *block)
192 char Id[BLKHDR_ID_LENGTH+1];
193 uint32_t CheckSum, BlockCheckSum;
196 uint32_t BlockNumber;
199 unser_begin(block->buf, BLKHDR_LENGTH);
200 unser_uint32(CheckSum);
201 unser_uint32(block_len);
202 unser_uint32(BlockNumber);
203 unser_bytes(Id, BLKHDR_ID_LENGTH);
204 ASSERT(unser_length(block->buf) == BLKHDR1_LENGTH);
206 Id[BLKHDR_ID_LENGTH] = 0;
208 bhl = BLKHDR1_LENGTH;
210 block->bufp = block->buf + bhl;
211 if (strncmp(Id, BLKHDR1_ID, BLKHDR_ID_LENGTH) != 0) {
212 Mmsg2(&dev->errmsg, _("Buffer ID error. Wanted: %s, got %s. Buffer discarded.\n"),
214 Emsg0(M_ERROR, 0, dev->errmsg);
217 } else if (Id[3] == '2') {
218 unser_uint32(block->VolSessionId);
219 unser_uint32(block->VolSessionTime);
220 bhl = BLKHDR2_LENGTH;
222 block->bufp = block->buf + bhl;
223 if (strncmp(Id, BLKHDR2_ID, BLKHDR_ID_LENGTH) != 0) {
224 Mmsg2(&dev->errmsg, _("Buffer ID error. Wanted: %s, got %s. Buffer discarded.\n"),
226 Emsg0(M_ERROR, 0, dev->errmsg);
230 Mmsg1(&dev->errmsg, _("Expected block-id BB01 or BB02, got %s. Buffer discarded.\n"), Id);
231 Emsg0(M_ERROR, 0, dev->errmsg);
236 if (block_len > MAX_BLOCK_LENGTH) {
237 Mmsg1(&dev->errmsg, _("Block length %u is insane (too large), probably due to a bad archive.\n"),
239 Emsg0(M_ERROR, 0, dev->errmsg);
243 Dmsg1(190, "unser_block_header block_len=%d\n", block_len);
244 /* Find end of block or end of buffer whichever is smaller */
245 if (block_len > block->read_len) {
246 block_end = block->read_len;
248 block_end = block_len;
250 block->binbuf = block_end - bhl;
251 block->block_len = block_len;
252 block->BlockNumber = BlockNumber;
253 Dmsg3(190, "Read binbuf = %d %d block_len=%d\n", block->binbuf,
255 if (block_len <= block->read_len) {
256 BlockCheckSum = bcrc32((uint8_t *)block->buf+BLKHDR_CS_LENGTH,
257 block_len-BLKHDR_CS_LENGTH);
258 if (BlockCheckSum != CheckSum) {
259 Dmsg2(00, "Block checksum mismatch: calc=%x blk=%x\n", BlockCheckSum,
261 Mmsg3(&dev->errmsg, _("Block checksum mismatch in block %u: calc=%x blk=%x\n"),
262 (unsigned)BlockNumber, BlockCheckSum, CheckSum);
270 * Write a block to the device, with locking and unlocking
272 * Returns: 1 on success
276 int write_block_to_device(JCR *jcr, DEVICE *dev, DEV_BLOCK *block)
282 * If a new volume has been mounted since our last write
283 * Create a JobMedia record for the previous volume written,
284 * and set new parameters to write this volume
287 /* Create a jobmedia record for this job */
288 if (!dir_create_jobmedia_record(jcr)) {
289 Jmsg(jcr, M_ERROR, 0, _("Could not create JobMedia record for Volume=\"%s\" Job=%s\n"),
290 jcr->VolCatInfo.VolCatName, jcr->Job);
291 set_new_volume_parameters(jcr, dev);
295 set_new_volume_parameters(jcr, dev);
298 if (!write_block_to_dev(jcr, dev, block)) {
299 stat = fixup_device_block_write_error(jcr, dev, block);
307 * Write a block to the device
309 * Returns: 1 on success or EOT
312 int write_block_to_dev(JCR *jcr, DEVICE *dev, DEV_BLOCK *block)
315 uint32_t wlen; /* length to write */
316 int hit_max1, hit_max2;
319 #ifdef NO_TAPE_WRITE_TEST
323 ASSERT(block->binbuf == ((uint32_t) (block->bufp - block->buf)));
325 /* dump_block(block, "before write"); */
326 if (dev->state & ST_WEOT) {
327 Dmsg0(100, "return write_block_to_dev with ST_WEOT\n");
328 Jmsg(jcr, M_FATAL, 0, _("Cannot write block. Device at EOM.\n"));
331 wlen = block->binbuf;
332 if (wlen <= WRITE_BLKHDR_LENGTH) { /* Does block have data in it? */
333 Dmsg0(100, "return write_block_to_dev no data to write\n");
337 * Clear to the end of the buffer if it is not full,
338 * and on tape devices, apply min and fixed blocking.
340 if (wlen != block->buf_len) {
341 uint32_t blen; /* current buffer length */
343 Dmsg2(200, "binbuf=%d buf_len=%d\n", block->binbuf, block->buf_len);
346 /* Adjust write size to min/max for tapes only */
347 if (dev->state & ST_TAPE) {
348 if (wlen < dev->min_block_size) {
349 wlen = ((dev->min_block_size + TAPE_BSIZE - 1) / TAPE_BSIZE) * TAPE_BSIZE;
351 /* check for fixed block size */
352 if (dev->min_block_size == dev->max_block_size) {
353 wlen = block->buf_len; /* fixed block size already rounded */
357 memset(block->bufp, 0, wlen-blen); /* clear garbage */
361 ser_block_header(block);
363 /* Limit maximum Volume size to value specified by user */
364 hit_max1 = (dev->max_volume_size > 0) &&
365 ((dev->VolCatInfo.VolCatBytes + block->binbuf)) >= dev->max_volume_size;
366 hit_max2 = (dev->VolCatInfo.VolCatMaxBytes > 0) &&
367 ((dev->VolCatInfo.VolCatBytes + block->binbuf)) >= dev->VolCatInfo.VolCatMaxBytes;
368 if (hit_max1 || hit_max2) {
371 Dmsg0(10, "==== Output bytes Triggered medium max capacity.\n");
373 max_cap = dev->max_volume_size;
375 max_cap = dev->VolCatInfo.VolCatMaxBytes;
377 Jmsg(jcr, M_INFO, 0, _("User defined maximum volume capacity %s exceeded on device %s.\n"),
378 edit_uint64(max_cap, ed1), dev->dev_name);
379 block->write_failed = true;
380 weof_dev(dev, 1); /* end the tape */
381 weof_dev(dev, 1); /* write second eof */
382 dev->state |= (ST_EOF | ST_EOT | ST_WEOT);
386 /* Limit maximum File size on volume to user specified value */
387 if (dev->state & ST_TAPE) {
388 if ((dev->max_file_size > 0) &&
389 (dev->file_addr+block->binbuf) >= dev->max_file_size) {
390 if (weof_dev(dev, 1) != 0) { /* write eof */
391 Jmsg(jcr, M_ERROR, 0, "%s", dev->errmsg);
392 /* Plunge on anyway -- if tape is bad we will die on write */
397 dev->VolCatInfo.VolCatWrites++;
398 Dmsg1(300, "Write block of %u bytes\n", wlen);
399 stat = write(dev->fd, block->buf, (size_t)wlen);
400 if (stat != (ssize_t)wlen) {
401 /* We should check for errno == ENOSPC, BUT many
402 * devices simply report EIO when the volume is full.
403 * With a little more thought we may be able to check
404 * capacity and distinguish real errors and EOT
405 * conditions. In any case, we probably want to
406 * simulate an End of Medium.
409 /* I have added the ifdefing here because it appears on
410 * FreeBSD where MTIOCERRSTAT is defined, this not only
411 * clears the error but clears the residual unwritten
412 * buffers -> data loss. As a consequence, on those
413 * systems (FreeBSD like), do the clrerror() only after
414 * the weof_dev() call.
416 clrerror_dev(dev, -1);
417 if (dev->dev_errno == 0) {
418 dev->dev_errno = ENOSPC; /* out of space */
420 Jmsg(jcr, M_ERROR, 0, _("Write error on device %s. ERR=%s.\n"),
421 dev->dev_name, strerror(dev->dev_errno));
423 dev->dev_errno = ENOSPC; /* out of space */
424 Jmsg3(jcr, M_INFO, 0, _("End of medium on device %s. Write of %u bytes got %d.\n"),
425 dev->dev_name, wlen, stat);
428 Dmsg6(100, "=== Write error. size=%u rtn=%d dev_blk=%d blk_blk=%d errno=%d: ERR=%s\n",
429 wlen, stat, dev->block_num, block->BlockNumber, dev->dev_errno, strerror(dev->dev_errno));
431 block->write_failed = true;
432 if (weof_dev(dev, 2) != 0) { /* end the tape */
433 Jmsg(jcr, M_ERROR, 0, "%s", dev->errmsg);
435 dev->state |= (ST_EOF | ST_EOT | ST_WEOT);
438 #define CHECK_LAST_BLOCK
439 #ifdef CHECK_LAST_BLOCK
441 * If the device is a tape and it supports backspace record,
442 * we backspace over two eof marks and over the last record,
443 * then re-read it and verify that the block number is
446 if (dev->state & ST_TAPE && dev_cap(dev, CAP_BSR)) {
448 /* Now back up over what we wrote and read the last block */
449 if (bsf_dev(dev, 1) != 0 || bsf_dev(dev, 1) != 0) {
451 Jmsg(jcr, M_ERROR, 0, _("Backspace file at EOT failed. ERR=%s\n"), strerror(dev->dev_errno));
453 /* Backspace over record */
454 if (ok && bsr_dev(dev, 1) != 0) {
456 Jmsg(jcr, M_ERROR, 0, _("Backspace record at EOT failed. ERR=%s\n"), strerror(dev->dev_errno));
458 * On FreeBSD systems, if the user got here, it is likely that his/her
459 * tape drive is "frozen". The correct thing to do is a
460 * rewind(), but if we do that, higher levels in cleaning up, will
461 * most likely write the EOS record over the beginning of the
462 * tape. The rewind *is* done later in mount.c when another
463 * tape is requested. Note, the clrerror_dev() call in bsr_dev()
464 * calls ioctl(MTCERRSTAT), which *should* fix the problem.
468 DEV_BLOCK *lblock = new_block(dev);
469 /* Note, this can destroy dev->errmsg */
470 if (!read_block_from_dev(jcr, dev, lblock, NO_BLOCK_NUMBER_CHECK)) {
471 Jmsg(jcr, M_ERROR, 0, _("Re-read last block at EOT failed. ERR=%s"), dev->errmsg);
473 if (lblock->BlockNumber+1 == block->BlockNumber) {
474 Jmsg(jcr, M_INFO, 0, _("Re-read of last block succeeded.\n"));
476 Jmsg(jcr, M_ERROR, 0, _(
477 "Re-read of last block failed. Last block=%u Current block=%u.\n"),
478 lblock->BlockNumber, block->BlockNumber);
488 /* We successfully wrote the block, now do housekeeping */
490 dev->VolCatInfo.VolCatBytes += block->binbuf;
491 dev->VolCatInfo.VolCatBlocks++;
492 dev->file_addr += wlen;
493 dev->EndBlock = dev->block_num;
494 dev->EndFile = dev->file;
496 block->BlockNumber++;
498 /* Update jcr values */
499 if (dev->state & ST_TAPE) {
500 jcr->EndBlock = dev->EndBlock;
501 jcr->EndFile = dev->EndFile;
503 jcr->EndBlock = (uint32_t)dev->file_addr;
504 jcr->EndFile = (uint32_t)(dev->file_addr >> 32);
506 if (jcr->VolFirstIndex == 0 && block->FirstIndex > 0) {
507 jcr->VolFirstIndex = block->FirstIndex;
509 if (block->LastIndex > 0) {
510 jcr->VolLastIndex = block->LastIndex;
512 jcr->WroteVol = true;
514 Dmsg2(190, "write_block: wrote block %d bytes=%d\n", dev->block_num,
521 * Read block with locking
524 int read_block_from_device(JCR *jcr, DEVICE *dev, DEV_BLOCK *block, bool check_block_numbers)
527 Dmsg0(90, "Enter read_block_from_device\n");
529 stat = read_block_from_dev(jcr, dev, block, check_block_numbers);
531 Dmsg0(90, "Leave read_block_from_device\n");
536 * Read the next block into the block structure and unserialize
537 * the block header. For a file, the block may be partially
538 * or completely in the current buffer.
540 int read_block_from_dev(JCR *jcr, DEVICE *dev, DEV_BLOCK *block, bool check_block_numbers)
544 uint32_t BlockNumber;
548 Dmsg1(100, "Full read() in read_block_from_device() len=%d\n",
552 Mmsg1(&dev->errmsg, _("Block buffer size looping problem on device %s\n"),
554 Jmsg(jcr, M_ERROR, 0, "%s", dev->errmsg);
559 stat = read(dev->fd, block->buf, (size_t)block->buf_len);
561 dev->VolCatInfo.VolCatErrors++;
563 } while (stat == -1 && (errno == EINTR || errno == EIO) && retry++ < 11);
565 Dmsg1(90, "Read device got: ERR=%s\n", strerror(errno));
566 clrerror_dev(dev, -1);
568 Mmsg2(&dev->errmsg, _("Read error on device %s. ERR=%s.\n"),
569 dev->dev_name, strerror(dev->dev_errno));
570 Jmsg(jcr, M_ERROR, 0, "%s", dev->errmsg);
571 if (dev->state & ST_EOF) { /* EOF just seen? */
572 dev->state |= ST_EOT; /* yes, error => EOT */
576 Dmsg1(90, "Read device got %d bytes\n", stat);
577 if (stat == 0) { /* Got EOF ! */
578 dev->block_num = block->read_len = 0;
579 Mmsg1(&dev->errmsg, _("Read zero bytes on device %s.\n"), dev->dev_name);
580 if (dev->state & ST_EOF) { /* EOF already read? */
581 dev->state |= ST_EOT; /* yes, 2 EOFs => EOT */
585 dev->file++; /* increment file */
586 dev->state |= ST_EOF; /* set EOF read */
588 return 0; /* return eof */
590 /* Continue here for successful read */
591 block->read_len = stat; /* save length read */
592 if (block->read_len < BLKHDR2_LENGTH) {
593 Mmsg2(&dev->errmsg, _("Very short block of %d bytes on device %s discarded.\n"),
594 block->read_len, dev->dev_name);
595 Jmsg(jcr, M_ERROR, 0, "%s", dev->errmsg);
596 dev->state |= ST_SHORT; /* set short block */
597 block->read_len = block->binbuf = 0;
598 return 0; /* return error */
601 BlockNumber = block->BlockNumber + 1;
602 if (!unser_block_header(dev, block)) {
608 * If the block is bigger than the buffer, we reposition for
609 * re-reading the block, allocate a buffer of the correct size,
612 if (block->block_len > block->buf_len) {
613 Mmsg2(&dev->errmsg, _("Block length %u is greater than buffer %u. Attempting recovery.\n"),
614 block->block_len, block->buf_len);
615 Jmsg(jcr, M_ERROR, 0, "%s", dev->errmsg);
616 Pmsg1(000, "%s", dev->errmsg);
617 /* Attempt to reposition to re-read the block */
618 if (dev->state & ST_TAPE) {
619 Dmsg0(100, "Backspace record for reread.\n");
620 if (bsr_dev(dev, 1) != 0) {
621 Jmsg(jcr, M_ERROR, 0, "%s", dev->errmsg);
626 Dmsg0(100, "Seek to beginning of block for reread.\n");
627 off_t pos = lseek(dev->fd, (off_t)0, SEEK_CUR); /* get curr pos */
628 pos -= block->read_len;
629 lseek(dev->fd, pos, SEEK_SET);
631 Mmsg1(&dev->errmsg, _("Setting block buffer size to %u bytes.\n"), block->block_len);
632 Jmsg(jcr, M_INFO, 0, "%s", dev->errmsg);
633 Pmsg1(000, "%s", dev->errmsg);
634 /* Set new block length */
635 dev->max_block_size = block->block_len;
636 block->buf_len = block->block_len;
637 free_memory(block->buf);
638 block->buf = get_memory(block->buf_len);
641 goto reread; /* re-read block with correct block size */
644 if (block->block_len > block->read_len) {
645 Mmsg2(&dev->errmsg, _("Short block of %d bytes on device %s discarded.\n"),
646 block->read_len, dev->dev_name);
647 Jmsg(jcr, M_ERROR, 0, "%s", dev->errmsg);
648 dev->state |= ST_SHORT; /* set short block */
649 block->read_len = block->binbuf = 0;
650 return 0; /* return error */
653 dev->state &= ~(ST_EOF|ST_SHORT); /* clear EOF and short block */
654 dev->VolCatInfo.VolCatReads++;
655 dev->VolCatInfo.VolCatRBytes += block->read_len;
657 dev->VolCatInfo.VolCatBytes += block->block_len;
658 dev->VolCatInfo.VolCatBlocks++;
659 dev->file_addr += block->block_len;
660 dev->EndBlock = dev->block_num;
661 dev->EndFile = dev->file;
664 /* Update jcr values */
665 if (dev->state & ST_TAPE) {
666 jcr->EndBlock = dev->EndBlock;
667 jcr->EndFile = dev->EndFile;
669 jcr->EndBlock = (uint32_t)dev->file_addr;
670 jcr->EndFile = (uint32_t)(dev->file_addr >> 32);
674 * If we read a short block on disk,
675 * seek to beginning of next block. This saves us
676 * from shuffling blocks around in the buffer. Take a
677 * look at this from an efficiency stand point later, but
678 * it should only happen once at the end of each job.
680 * I've been lseek()ing negative relative to SEEK_CUR for 30
681 * years now. However, it seems that with the new off_t definition,
682 * it is not possible to seek negative amounts, so we use two
683 * lseek(). One to get the position, then the second to do an
684 * absolute positioning -- so much for efficiency. KES Sep 02.
686 Dmsg0(200, "At end of read block\n");
687 if (block->read_len > block->block_len && !(dev->state & ST_TAPE)) {
688 off_t pos = lseek(dev->fd, (off_t)0, SEEK_CUR); /* get curr pos */
689 pos -= (block->read_len - block->block_len);
690 lseek(dev->fd, pos, SEEK_SET);
691 Dmsg2(100, "Did lseek blk_size=%d rdlen=%d\n", block->block_len,
694 Dmsg2(200, "Exit read_block read_len=%d block_len=%d\n",
695 block->read_len, block->block_len);
696 block->block_read = true;