2 * Copyright (c) 1980, 1991, 1993
3 * The Regents of the University of California. All rights reserved.
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6 * modification, are permitted provided that the following conditions
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13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
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36 static char sccsid[] = "@(#)tape.c 8.4 (Berkeley) 5/1/95";
38 static const char rcsid[] =
39 "$FreeBSD: src/sbin/dump/tape.c,v 1.12.2.3 2002/02/23 22:32:51 iedowse Exp $";
42 #include <sys/param.h>
43 #include <sys/socket.h>
48 #include <sys/vnode.h>
51 #include <ufs/inode.h>
53 #include <ufs/ufs/dinode.h>
54 #include <ufs/ffs/fs.h>
57 #include <protocols/dumprestore.h>
74 int writesize; /* size of malloc()ed buffer for tape */
75 long lastspclrec = -1; /* tape block number of last written header */
76 int trecno = 0; /* next record to write in current block */
77 extern long blocksperfile; /* number of blocks per output file */
78 long blocksthisvol; /* number of blocks on current output file */
79 extern int ntrec; /* blocking factor on tape */
84 static int atomic __P((ssize_t (*)(), int, char *, int));
85 static void doslave __P((int, int));
86 static void enslave __P((void));
87 static void flushtape __P((void));
88 static void killall __P((void));
89 static void rollforward __P((void));
92 * Concurrent dump mods (Caltech) - disk block reading and tape writing
93 * are exported to several slave processes. While one slave writes the
94 * tape, the others read disk blocks; they pass control of the tape in
95 * a ring via signals. The parent process traverses the filesystem and
96 * sends writeheader()'s and lists of daddr's to the slaves via pipes.
97 * The following structure defines the instruction packets sent to slaves.
105 #define SLAVES 3 /* 1 slave writing, 1 reading, 1 for slack */
107 int tapea; /* header number at start of this chunk */
108 int count; /* count to next header (used for TS_TAPE */
110 int inode; /* inode that we are currently dealing with */
111 int fd; /* FD for this slave */
112 int pid; /* PID for this slave */
113 int sent; /* 1 == we've sent this slave requests */
114 int firstrec; /* record number of this block */
115 char (*tblock)[TP_BSIZE]; /* buffer for data blocks */
116 struct req *req; /* buffer for requests */
120 char (*nextblock)[TP_BSIZE];
122 int master; /* pid of master, for sending error signals */
123 int tenths; /* length of tape used per block written */
124 static int caught; /* have we caught the signal to proceed? */
125 static int ready; /* have we reached the lock point without having */
126 /* received the SIGUSR2 signal from the prev slave? */
127 static jmp_buf jmpbuf; /* where to jump to if we are ready when the */
128 /* SIGUSR2 arrives from the previous slave */
133 int pgoff = getpagesize() - 1;
137 writesize = ntrec * TP_BSIZE;
138 reqsiz = (ntrec + 1) * sizeof(struct req);
140 * CDC 92181's and 92185's make 0.8" gaps in 1600-bpi start/stop mode
141 * (see DEC TU80 User's Guide). The shorter gaps of 6250-bpi require
142 * repositioning after stopping, i.e, streaming mode, where the gap is
143 * variable, 0.30" to 0.45". The gap is maximal when the tape stops.
145 if (blocksperfile == 0 && !unlimited)
146 tenths = writesize / density +
147 (cartridge ? 16 : density == 625 ? 5 : 8);
149 * Allocate tape buffer contiguous with the array of instruction
150 * packets, so flushtape() can write them together with one write().
151 * Align tape buffer on page boundary to speed up tape write().
153 for (i = 0; i <= SLAVES; i++) {
155 malloc((unsigned)(reqsiz + writesize + pgoff + TP_BSIZE));
158 slaves[i].tblock = (char (*)[TP_BSIZE])
159 (((long)&buf[ntrec + 1] + pgoff) &~ pgoff);
160 slaves[i].req = (struct req *)slaves[i].tblock - ntrec - 1;
166 nextblock = slp->tblock;
176 slp->req[trecno].dblk = (daddr_t)0;
177 slp->req[trecno].count = 1;
179 *(union u_spcl *)(*(nextblock)++) = *(union u_spcl *)dp;
181 bcopy(dp, *(nextblock)++, sizeof (union u_spcl));
184 lastspclrec = spcl.c_tapea;
192 dumpblock(blkno, size)
196 int avail, tpblks, dblkno;
198 dblkno = fsbtodb(sblock, blkno);
199 tpblks = size >> tp_bshift;
200 while ((avail = MIN(tpblks, ntrec - trecno)) > 0) {
201 slp->req[trecno].dblk = dblkno;
202 slp->req[trecno].count = avail;
204 spcl.c_tapea += avail;
207 dblkno += avail << (tp_bshift - dev_bshift);
220 msg("write error on %s\n", tape);
221 quit("Cannot recover\n");
224 msg("write error %d blocks into volume %d\n", blocksthisvol, tapeno);
225 broadcast("DUMP WRITE ERROR!\n");
226 if (!query("Do you want to restart?"))
228 msg("Closing this volume. Prepare to restart with new media;\n");
229 msg("this dump volume will be rewritten.\n");
241 quit("Broken pipe\n");
250 int siz = (char *)nextblock - (char *)slp->req;
252 slp->req[trecno].count = 0; /* Sentinel */
254 if (atomic(write, slp->fd, (char *)slp->req, siz) != siz)
255 quit("error writing command pipe: %s\n", strerror(errno));
256 slp->sent = 1; /* we sent a request, read the response later */
258 lastfirstrec = slp->firstrec;
260 if (++slp >= &slaves[SLAVES])
263 /* Read results back from next slave */
265 if (atomic(read, slp->fd, (char *)&got, sizeof got)
267 perror(" DUMP: error reading command pipe in master");
272 /* Check for end of tape */
273 if (got < writesize) {
274 msg("End of tape detected\n");
277 * Drain the results, don't care what the values were.
278 * If we read them here then trewind won't...
280 for (i = 0; i < SLAVES; i++) {
281 if (slaves[i].sent) {
282 if (atomic(read, slaves[i].fd,
283 (char *)&got, sizeof got)
285 perror(" DUMP: error reading command pipe in master");
299 if (spcl.c_type != TS_END) {
300 for (i = 0; i < spcl.c_count; i++)
301 if (spcl.c_addr[i] != 0)
304 slp->count = lastspclrec + blks + 1 - spcl.c_tapea;
305 slp->tapea = spcl.c_tapea;
306 slp->firstrec = lastfirstrec + ntrec;
308 nextblock = slp->tblock;
311 blockswritten += ntrec;
312 blocksthisvol += ntrec;
313 if (!pipeout && !unlimited && (blocksperfile ?
314 (blocksthisvol >= blocksperfile) : (asize > tsize))) {
328 for (f = 0; f < SLAVES; f++) {
330 * Drain the results, but unlike EOT we DO (or should) care
331 * what the return values were, since if we detect EOT after
332 * we think we've written the last blocks to the tape anyway,
333 * we have to replay those blocks with rollforward.
335 * fixme: punt for now.
337 if (slaves[f].sent) {
338 if (atomic(read, slaves[f].fd, (char *)&got, sizeof got)
340 perror(" DUMP: error reading command pipe in master");
344 if (got != writesize) {
345 msg("EOT detected in last 2 tape records!\n");
346 msg("Use a longer tape, decrease the size estimate\n");
347 quit("or use no size estimate at all.\n");
350 (void) close(slaves[f].fd);
352 while (wait((int *)NULL) >= 0) /* wait for any signals from slaves */
358 msg("Closing %s\n", tape);
363 while (rmtopen(tape, 0) < 0)
369 if (fstat(tapefd, &sb) == 0 && S_ISFIFO(sb.st_mode)) {
373 (void) close(tapefd);
374 while ((f = open(tape, 0)) < 0)
382 time_t tstart_changevol, tend_changevol;
387 (void)time((time_t *)&(tstart_changevol));
389 msg("Change Volumes: Mount volume #%d\n", tapeno+1);
390 broadcast("CHANGE DUMP VOLUMES!\a\a\n");
392 while (!query("Is the new volume mounted and ready to go?"))
393 if (query("Do you want to abort?")) {
397 (void)time((time_t *)&(tend_changevol));
398 if ((tstart_changevol != (time_t)-1) && (tend_changevol != (time_t)-1))
399 tstart_writing += (tend_changevol - tstart_changevol);
405 register struct req *p, *q, *prev;
406 register struct slave *tslp;
407 int i, size, savedtapea, got;
408 union u_spcl *ntb, *otb;
409 tslp = &slaves[SLAVES];
410 ntb = (union u_spcl *)tslp->tblock[1];
413 * Each of the N slaves should have requests that need to
414 * be replayed on the next tape. Use the extra slave buffers
415 * (slaves[SLAVES]) to construct request lists to be sent to
416 * each slave in turn.
418 for (i = 0; i < SLAVES; i++) {
420 otb = (union u_spcl *)slp->tblock;
423 * For each request in the current slave, copy it to tslp.
427 for (p = slp->req; p->count > 0; p += p->count) {
430 *ntb++ = *otb++; /* copy the datablock also */
435 quit("rollforward: protocol botch");
447 nextblock = tslp->tblock;
448 savedtapea = spcl.c_tapea;
449 spcl.c_tapea = slp->tapea;
451 spcl.c_tapea = savedtapea;
452 lastspclrec = savedtapea - 1;
454 size = (char *)ntb - (char *)q;
455 if (atomic(write, slp->fd, (char *)q, size) != size) {
456 perror(" DUMP: error writing command pipe");
460 if (++slp >= &slaves[SLAVES])
465 if (prev->dblk != 0) {
467 * If the last one was a disk block, make the
468 * first of this one be the last bit of that disk
471 q->dblk = prev->dblk +
472 prev->count * (TP_BSIZE / DEV_BSIZE);
473 ntb = (union u_spcl *)tslp->tblock;
476 * It wasn't a disk block. Copy the data to its
477 * new location in the buffer.
480 *((union u_spcl *)tslp->tblock) = *ntb;
481 ntb = (union u_spcl *)tslp->tblock[1];
485 nextblock = slp->tblock;
491 * Clear the first slaves' response. One hopes that it
492 * worked ok, otherwise the tape is much too short!
495 if (atomic(read, slp->fd, (char *)&got, sizeof got)
497 perror(" DUMP: error reading command pipe in master");
502 if (got != writesize) {
503 quit("EOT detected at start of the tape!\n");
509 * We implement taking and restoring checkpoints on the tape level.
510 * When each tape is opened, a new process is created by forking; this
511 * saves all of the necessary context in the parent. The child
512 * continues the dump; the parent waits around, saving the context.
513 * If the child returns X_REWRITE, then it had problems writing that tape;
514 * this causes the parent to fork again, duplicating the context, and
515 * everything continues as if nothing had happened.
527 void (*interrupt_save)();
529 sig_t interrupt_save;
532 interrupt_save = signal(SIGINT, SIG_IGN);
533 parentpid = getpid();
536 (void)signal(SIGINT, interrupt_save);
538 * All signals are inherited...
540 setproctitle(NULL); /* Restore the proctitle. */
543 msg("Context save fork fails in parent %d\n", parentpid);
549 * save the context by waiting
550 * until the child doing all of the work returns.
551 * don't catch the interrupt
553 signal(SIGINT, SIG_IGN);
555 msg("Tape: %d; parent process: %d child process %d\n",
556 tapeno+1, parentpid, childpid);
558 while ((waitpid = wait(&status)) != childpid)
559 msg("Parent %d waiting for child %d has another child %d return\n",
560 parentpid, childpid, waitpid);
562 msg("Child %d returns LOB status %o\n",
563 childpid, status&0xFF);
565 status = (status >> 8) & 0xFF;
569 msg("Child %d finishes X_FINOK\n", childpid);
572 msg("Child %d finishes X_ABORT\n", childpid);
575 msg("Child %d finishes X_REWRITE\n", childpid);
578 msg("Child %d finishes unknown %d\n",
589 goto restore_check_point;
591 msg("Bad return code from dump: %d\n", status);
595 } else { /* we are the child; just continue */
597 sleep(4); /* allow time for parent's message to get out */
598 msg("Child on Tape %d has parent %d, my pid = %d\n",
599 tapeno+1, parentpid, getpid());
602 * If we have a name like "/dev/rmt0,/dev/rmt1",
603 * use the name before the comma first, and save
604 * the remaining names for subsequent volumes.
606 tapeno++; /* current tape sequence */
607 if (nexttape || strchr(tape, ',')) {
608 if (nexttape && *nexttape)
610 if ((p = strchr(tape, ',')) != NULL) {
615 msg("Dumping volume %d on %s\n", tapeno, tape);
618 while ((tapefd = (host ? rmtopen(tape, 2) :
619 pipeout ? 1 : open(tape, O_WRONLY|O_CREAT, 0666))) < 0)
621 while ((tapefd = (pipeout ? 1 :
622 open(tape, O_WRONLY|O_CREAT, 0666))) < 0)
625 msg("Cannot open output \"%s\".\n", tape);
626 if (!query("Do you want to retry the open?"))
630 enslave(); /* Share open tape file descriptor with slaves */
631 signal(SIGINFO, infosch);
636 newtape++; /* new tape signal */
637 spcl.c_count = slp->count;
639 * measure firstrec in TP_BSIZE units since restore doesn't
640 * know the correct ntrec value...
642 spcl.c_firstrec = slp->firstrec;
644 spcl.c_type = TS_TAPE;
645 spcl.c_flags |= DR_NEWHEADER;
646 writeheader((ino_t)slp->inode);
647 spcl.c_flags &=~ DR_NEWHEADER;
649 msg("Volume %d begins with blocks from inode %d\n",
659 if (master != 0 && master != getpid())
660 /* Signals master to call dumpabort */
661 (void) kill(master, SIGTERM);
664 msg("The ENTIRE dump is aborted.\n");
678 msg("pid = %d exits with status %d\n", getpid(), status);
684 * proceed - handler for SIGUSR2, used to synchronize IO between the slaves.
704 signal(SIGTERM, dumpabort); /* Slave sends SIGTERM on dumpabort() */
705 signal(SIGPIPE, sigpipe);
706 signal(SIGUSR1, tperror); /* Slave sends SIGUSR1 on tape errors */
707 signal(SIGUSR2, proceed); /* Slave sends SIGUSR2 to next slave */
709 for (i = 0; i < SLAVES; i++) {
710 if (i == slp - &slaves[0]) {
716 if (socketpair(AF_UNIX, SOCK_STREAM, 0, cmd) < 0 ||
717 (slaves[i].pid = fork()) < 0)
718 quit("too many slaves, %d (recompile smaller): %s\n",
721 slaves[i].fd = cmd[1];
723 if (slaves[i].pid == 0) { /* Slave starts up here */
724 for (j = 0; j <= i; j++)
725 (void) close(slaves[j].fd);
726 signal(SIGINT, SIG_IGN); /* Master handles this */
732 for (i = 0; i < SLAVES; i++)
733 (void) atomic(write, slaves[i].fd,
734 (char *) &slaves[(i + 1) % SLAVES].pid,
735 sizeof slaves[0].pid);
745 for (i = 0; i < SLAVES; i++)
746 if (slaves[i].pid > 0) {
747 (void) kill(slaves[i].pid, SIGKILL);
753 * Synchronization - each process has a lockfile, and shares file
754 * descriptors to the following process's lockfile. When our write
755 * completes, we release our lock on the following process's lock-
756 * file, allowing the following process to lock it and proceed. We
757 * get the lock back for the next cycle by swapping descriptors.
760 doslave(cmd, slave_number)
765 int nextslave, size, wrote, eot_count;
768 * Need our own seek pointer.
770 (void) close(diskfd);
771 if ((diskfd = open(disk, O_RDONLY)) < 0)
772 quit("slave couldn't reopen disk: %s\n", strerror(errno));
775 * Need the pid of the next slave in the loop...
777 if ((nread = atomic(read, cmd, (char *)&nextslave, sizeof nextslave))
778 != sizeof nextslave) {
779 quit("master/slave protocol botched - didn't get pid of next slave.\n");
783 * Get list of blocks to dump, read the blocks into tape buffer
785 while ((nread = atomic(read, cmd, (char *)slp->req, reqsiz)) == reqsiz) {
786 register struct req *p = slp->req;
788 for (trecno = 0; trecno < ntrec;
789 trecno += p->count, p += p->count) {
791 bread(p->dblk, slp->tblock[trecno],
792 p->count * TP_BSIZE);
794 if (p->count != 1 || atomic(read, cmd,
795 (char *)slp->tblock[trecno],
796 TP_BSIZE) != TP_BSIZE)
797 quit("master/slave protocol botched.\n");
800 if (setjmp(jmpbuf) == 0) {
808 /* Try to write the data... */
812 while (eot_count < 10 && size < writesize) {
815 wrote = rmtwrite(slp->tblock[0]+size,
819 wrote = write(tapefd, slp->tblock[0]+size,
822 printf("slave %d wrote %d\n", slave_number, wrote);
832 if (size != writesize)
833 printf("slave %d only wrote %d out of %d bytes and gave up.\n",
834 slave_number, size, writesize);
838 * Handle ENOSPC as an EOT condition.
840 if (wrote < 0 && errno == ENOSPC) {
849 (void) kill(master, SIGUSR1);
854 * pass size of write back to master
857 (void) atomic(write, cmd, (char *)&size, sizeof size);
861 * If partial write, don't want next slave to go.
862 * Also jolts him awake.
864 (void) kill(nextslave, SIGUSR2);
867 quit("error reading command pipe: %s\n", strerror(errno));
871 * Since a read from a pipe may not return all we asked for,
872 * or a write may not write all we ask if we get a signal,
873 * loop until the count is satisfied (or error).
876 atomic(func, fd, buf, count)
882 int got, need = count;
884 while ((got = (*func)(fd, buf, need)) > 0 && (need -= got) > 0)
886 return (got < 0 ? got : count - need);