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Diffstat (limited to 'sbin/dump/tape.c')
| -rw-r--r-- | sbin/dump/tape.c | 859 |
1 files changed, 859 insertions, 0 deletions
diff --git a/sbin/dump/tape.c b/sbin/dump/tape.c new file mode 100644 index 0000000..f6a4e5b --- /dev/null +++ b/sbin/dump/tape.c @@ -0,0 +1,859 @@ +/*- + * Copyright (c) 1980, 1991, 1993 + * The Regents of the University of California. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#ifndef lint +static char sccsid[] = "@(#)tape.c 8.2 (Berkeley) 3/17/94"; +#endif /* not lint */ + +#include <sys/param.h> +#include <sys/socket.h> +#include <sys/time.h> +#include <sys/wait.h> +#ifdef sunos +#include <sys/vnode.h> + +#include <ufs/fs.h> +#include <ufs/inode.h> +#else +#include <ufs/ffs/fs.h> +#include <ufs/ufs/dinode.h> +#endif + +#include <protocols/dumprestore.h> + +#include <errno.h> +#include <fcntl.h> +#include <setjmp.h> +#include <signal.h> +#include <stdio.h> +#ifdef __STDC__ +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#else +int write(), read(); +#endif + +#include "dump.h" +#include "pathnames.h" + +int writesize; /* size of malloc()ed buffer for tape */ +long lastspclrec = -1; /* tape block number of last written header */ +int trecno = 0; /* next record to write in current block */ +extern long blocksperfile; /* number of blocks per output file */ +long blocksthisvol; /* number of blocks on current output file */ +extern int ntrec; /* blocking factor on tape */ +extern int cartridge; +extern char *host; +char *nexttape; + +static int atomic __P((int (*)(), int, char *, int)); +static void doslave __P((int, int)); +static void enslave __P((void)); +static void flushtape __P((void)); +static void killall __P((void)); +static void rollforward __P((void)); + +/* + * Concurrent dump mods (Caltech) - disk block reading and tape writing + * are exported to several slave processes. While one slave writes the + * tape, the others read disk blocks; they pass control of the tape in + * a ring via signals. The parent process traverses the filesystem and + * sends writeheader()'s and lists of daddr's to the slaves via pipes. + * The following structure defines the instruction packets sent to slaves. + */ +struct req { + daddr_t dblk; + int count; +}; +int reqsiz; + +#define SLAVES 3 /* 1 slave writing, 1 reading, 1 for slack */ +struct slave { + int tapea; /* header number at start of this chunk */ + int count; /* count to next header (used for TS_TAPE */ + /* after EOT) */ + int inode; /* inode that we are currently dealing with */ + int fd; /* FD for this slave */ + int pid; /* PID for this slave */ + int sent; /* 1 == we've sent this slave requests */ + int firstrec; /* record number of this block */ + char (*tblock)[TP_BSIZE]; /* buffer for data blocks */ + struct req *req; /* buffer for requests */ +} slaves[SLAVES+1]; +struct slave *slp; + +char (*nextblock)[TP_BSIZE]; + +int master; /* pid of master, for sending error signals */ +int tenths; /* length of tape used per block written */ +static int caught; /* have we caught the signal to proceed? */ +static int ready; /* have we reached the lock point without having */ + /* received the SIGUSR2 signal from the prev slave? */ +static jmp_buf jmpbuf; /* where to jump to if we are ready when the */ + /* SIGUSR2 arrives from the previous slave */ + +int +alloctape() +{ + int pgoff = getpagesize() - 1; + char *buf; + int i; + + writesize = ntrec * TP_BSIZE; + reqsiz = (ntrec + 1) * sizeof(struct req); + /* + * CDC 92181's and 92185's make 0.8" gaps in 1600-bpi start/stop mode + * (see DEC TU80 User's Guide). The shorter gaps of 6250-bpi require + * repositioning after stopping, i.e, streaming mode, where the gap is + * variable, 0.30" to 0.45". The gap is maximal when the tape stops. + */ + if (blocksperfile == 0) + tenths = writesize / density + + (cartridge ? 16 : density == 625 ? 5 : 8); + /* + * Allocate tape buffer contiguous with the array of instruction + * packets, so flushtape() can write them together with one write(). + * Align tape buffer on page boundary to speed up tape write(). + */ + for (i = 0; i <= SLAVES; i++) { + buf = (char *) + malloc((unsigned)(reqsiz + writesize + pgoff + TP_BSIZE)); + if (buf == NULL) + return(0); + slaves[i].tblock = (char (*)[TP_BSIZE]) + (((long)&buf[ntrec + 1] + pgoff) &~ pgoff); + slaves[i].req = (struct req *)slaves[i].tblock - ntrec - 1; + } + slp = &slaves[0]; + slp->count = 1; + slp->tapea = 0; + slp->firstrec = 0; + nextblock = slp->tblock; + return(1); +} + +void +writerec(dp, isspcl) + char *dp; + int isspcl; +{ + + slp->req[trecno].dblk = (daddr_t)0; + slp->req[trecno].count = 1; + *(union u_spcl *)(*(nextblock)++) = *(union u_spcl *)dp; + if (isspcl) + lastspclrec = spcl.c_tapea; + trecno++; + spcl.c_tapea++; + if (trecno >= ntrec) + flushtape(); +} + +void +dumpblock(blkno, size) + daddr_t blkno; + int size; +{ + int avail, tpblks, dblkno; + + dblkno = fsbtodb(sblock, blkno); + tpblks = size >> tp_bshift; + while ((avail = MIN(tpblks, ntrec - trecno)) > 0) { + slp->req[trecno].dblk = dblkno; + slp->req[trecno].count = avail; + trecno += avail; + spcl.c_tapea += avail; + if (trecno >= ntrec) + flushtape(); + dblkno += avail << (tp_bshift - dev_bshift); + tpblks -= avail; + } +} + +int nogripe = 0; + +void +tperror(signo) + int signo; +{ + + if (pipeout) { + msg("write error on %s\n", tape); + quit("Cannot recover\n"); + /* NOTREACHED */ + } + msg("write error %d blocks into volume %d\n", blocksthisvol, tapeno); + broadcast("DUMP WRITE ERROR!\n"); + if (!query("Do you want to restart?")) + dumpabort(0); + msg("Closing this volume. Prepare to restart with new media;\n"); + msg("this dump volume will be rewritten.\n"); + killall(); + nogripe = 1; + close_rewind(); + Exit(X_REWRITE); +} + +void +sigpipe(signo) + int signo; +{ + + quit("Broken pipe\n"); +} + +static void +flushtape() +{ + int i, blks, got; + long lastfirstrec; + + int siz = (char *)nextblock - (char *)slp->req; + + slp->req[trecno].count = 0; /* Sentinel */ + + if (atomic(write, slp->fd, (char *)slp->req, siz) != siz) + quit("error writing command pipe: %s\n", strerror(errno)); + slp->sent = 1; /* we sent a request, read the response later */ + + lastfirstrec = slp->firstrec; + + if (++slp >= &slaves[SLAVES]) + slp = &slaves[0]; + + /* Read results back from next slave */ + if (slp->sent) { + if (atomic(read, slp->fd, (char *)&got, sizeof got) + != sizeof got) { + perror(" DUMP: error reading command pipe in master"); + dumpabort(0); + } + slp->sent = 0; + + /* Check for end of tape */ + if (got < writesize) { + msg("End of tape detected\n"); + + /* + * Drain the results, don't care what the values were. + * If we read them here then trewind won't... + */ + for (i = 0; i < SLAVES; i++) { + if (slaves[i].sent) { + if (atomic(read, slaves[i].fd, + (char *)&got, sizeof got) + != sizeof got) { + perror(" DUMP: error reading command pipe in master"); + dumpabort(0); + } + slaves[i].sent = 0; + } + } + + close_rewind(); + rollforward(); + return; + } + } + + blks = 0; + if (spcl.c_type != TS_END) { + for (i = 0; i < spcl.c_count; i++) + if (spcl.c_addr[i] != 0) + blks++; + } + slp->count = lastspclrec + blks + 1 - spcl.c_tapea; + slp->tapea = spcl.c_tapea; + slp->firstrec = lastfirstrec + ntrec; + slp->inode = curino; + nextblock = slp->tblock; + trecno = 0; + asize += tenths; + blockswritten += ntrec; + blocksthisvol += ntrec; + if (!pipeout && (blocksperfile ? + (blocksthisvol >= blocksperfile) : (asize > tsize))) { + close_rewind(); + startnewtape(0); + } + timeest(); +} + +void +trewind() +{ + int f; + int got; + + for (f = 0; f < SLAVES; f++) { + /* + * Drain the results, but unlike EOT we DO (or should) care + * what the return values were, since if we detect EOT after + * we think we've written the last blocks to the tape anyway, + * we have to replay those blocks with rollforward. + * + * fixme: punt for now. + */ + if (slaves[f].sent) { + if (atomic(read, slaves[f].fd, (char *)&got, sizeof got) + != sizeof got) { + perror(" DUMP: error reading command pipe in master"); + dumpabort(0); + } + slaves[f].sent = 0; + if (got != writesize) { + msg("EOT detected in last 2 tape records!\n"); + msg("Use a longer tape, decrease the size estimate\n"); + quit("or use no size estimate at all.\n"); + } + } + (void) close(slaves[f].fd); + } + while (wait((int *)NULL) >= 0) /* wait for any signals from slaves */ + /* void */; + + if (pipeout) + return; + + msg("Closing %s\n", tape); + +#ifdef RDUMP + if (host) { + rmtclose(); + while (rmtopen(tape, 0) < 0) + sleep(10); + rmtclose(); + return; + } +#endif + (void) close(tapefd); + while ((f = open(tape, 0)) < 0) + sleep (10); + (void) close(f); +} + +void +close_rewind() +{ + trewind(); + if (nexttape) + return; + if (!nogripe) { + msg("Change Volumes: Mount volume #%d\n", tapeno+1); + broadcast("CHANGE DUMP VOLUMES!\7\7\n"); + } + while (!query("Is the new volume mounted and ready to go?")) + if (query("Do you want to abort?")) { + dumpabort(0); + /*NOTREACHED*/ + } +} + +void +rollforward() +{ + register struct req *p, *q, *prev; + register struct slave *tslp; + int i, size, savedtapea, got; + union u_spcl *ntb, *otb; + tslp = &slaves[SLAVES]; + ntb = (union u_spcl *)tslp->tblock[1]; + + /* + * Each of the N slaves should have requests that need to + * be replayed on the next tape. Use the extra slave buffers + * (slaves[SLAVES]) to construct request lists to be sent to + * each slave in turn. + */ + for (i = 0; i < SLAVES; i++) { + q = &tslp->req[1]; + otb = (union u_spcl *)slp->tblock; + + /* + * For each request in the current slave, copy it to tslp. + */ + + prev = NULL; + for (p = slp->req; p->count > 0; p += p->count) { + *q = *p; + if (p->dblk == 0) + *ntb++ = *otb++; /* copy the datablock also */ + prev = q; + q += q->count; + } + if (prev == NULL) + quit("rollforward: protocol botch"); + if (prev->dblk != 0) + prev->count -= 1; + else + ntb--; + q -= 1; + q->count = 0; + q = &tslp->req[0]; + if (i == 0) { + q->dblk = 0; + q->count = 1; + trecno = 0; + nextblock = tslp->tblock; + savedtapea = spcl.c_tapea; + spcl.c_tapea = slp->tapea; + startnewtape(0); + spcl.c_tapea = savedtapea; + lastspclrec = savedtapea - 1; + } + size = (char *)ntb - (char *)q; + if (atomic(write, slp->fd, (char *)q, size) != size) { + perror(" DUMP: error writing command pipe"); + dumpabort(0); + } + slp->sent = 1; + if (++slp >= &slaves[SLAVES]) + slp = &slaves[0]; + + q->count = 1; + + if (prev->dblk != 0) { + /* + * If the last one was a disk block, make the + * first of this one be the last bit of that disk + * block... + */ + q->dblk = prev->dblk + + prev->count * (TP_BSIZE / DEV_BSIZE); + ntb = (union u_spcl *)tslp->tblock; + } else { + /* + * It wasn't a disk block. Copy the data to its + * new location in the buffer. + */ + q->dblk = 0; + *((union u_spcl *)tslp->tblock) = *ntb; + ntb = (union u_spcl *)tslp->tblock[1]; + } + } + slp->req[0] = *q; + nextblock = slp->tblock; + if (q->dblk == 0) + nextblock++; + trecno = 1; + + /* + * Clear the first slaves' response. One hopes that it + * worked ok, otherwise the tape is much too short! + */ + if (slp->sent) { + if (atomic(read, slp->fd, (char *)&got, sizeof got) + != sizeof got) { + perror(" DUMP: error reading command pipe in master"); + dumpabort(0); + } + slp->sent = 0; + + if (got != writesize) { + quit("EOT detected at start of the tape!\n"); + } + } +} + +/* + * We implement taking and restoring checkpoints on the tape level. + * When each tape is opened, a new process is created by forking; this + * saves all of the necessary context in the parent. The child + * continues the dump; the parent waits around, saving the context. + * If the child returns X_REWRITE, then it had problems writing that tape; + * this causes the parent to fork again, duplicating the context, and + * everything continues as if nothing had happened. + */ +void +startnewtape(top) + int top; +{ + int parentpid; + int childpid; + int status; + int waitpid; + char *p; +#ifdef sunos + void (*interrupt_save)(); +#else + sig_t interrupt_save; +#endif + + interrupt_save = signal(SIGINT, SIG_IGN); + parentpid = getpid(); + +restore_check_point: + (void)signal(SIGINT, interrupt_save); + /* + * All signals are inherited... + */ + childpid = fork(); + if (childpid < 0) { + msg("Context save fork fails in parent %d\n", parentpid); + Exit(X_ABORT); + } + if (childpid != 0) { + /* + * PARENT: + * save the context by waiting + * until the child doing all of the work returns. + * don't catch the interrupt + */ + signal(SIGINT, SIG_IGN); +#ifdef TDEBUG + msg("Tape: %d; parent process: %d child process %d\n", + tapeno+1, parentpid, childpid); +#endif /* TDEBUG */ + while ((waitpid = wait(&status)) != childpid) + msg("Parent %d waiting for child %d has another child %d return\n", + parentpid, childpid, waitpid); + if (status & 0xFF) { + msg("Child %d returns LOB status %o\n", + childpid, status&0xFF); + } + status = (status >> 8) & 0xFF; +#ifdef TDEBUG + switch(status) { + case X_FINOK: + msg("Child %d finishes X_FINOK\n", childpid); + break; + case X_ABORT: + msg("Child %d finishes X_ABORT\n", childpid); + break; + case X_REWRITE: + msg("Child %d finishes X_REWRITE\n", childpid); + break; + default: + msg("Child %d finishes unknown %d\n", + childpid, status); + break; + } +#endif /* TDEBUG */ + switch(status) { + case X_FINOK: + Exit(X_FINOK); + case X_ABORT: + Exit(X_ABORT); + case X_REWRITE: + goto restore_check_point; + default: + msg("Bad return code from dump: %d\n", status); + Exit(X_ABORT); + } + /*NOTREACHED*/ + } else { /* we are the child; just continue */ +#ifdef TDEBUG + sleep(4); /* allow time for parent's message to get out */ + msg("Child on Tape %d has parent %d, my pid = %d\n", + tapeno+1, parentpid, getpid()); +#endif /* TDEBUG */ + /* + * If we have a name like "/dev/rmt0,/dev/rmt1", + * use the name before the comma first, and save + * the remaining names for subsequent volumes. + */ + tapeno++; /* current tape sequence */ + if (nexttape || index(tape, ',')) { + if (nexttape && *nexttape) + tape = nexttape; + if ((p = index(tape, ',')) != NULL) { + *p = '\0'; + nexttape = p + 1; + } else + nexttape = NULL; + msg("Dumping volume %d on %s\n", tapeno, tape); + } +#ifdef RDUMP + while ((tapefd = (host ? rmtopen(tape, 2) : + pipeout ? 1 : open(tape, O_WRONLY|O_CREAT, 0666))) < 0) +#else + while ((tapefd = (pipeout ? 1 : + open(tape, O_WRONLY|O_CREAT, 0666))) < 0) +#endif + { + msg("Cannot open output \"%s\".\n", tape); + if (!query("Do you want to retry the open?")) + dumpabort(0); + } + + enslave(); /* Share open tape file descriptor with slaves */ + + asize = 0; + blocksthisvol = 0; + if (top) + newtape++; /* new tape signal */ + spcl.c_count = slp->count; + /* + * measure firstrec in TP_BSIZE units since restore doesn't + * know the correct ntrec value... + */ + spcl.c_firstrec = slp->firstrec; + spcl.c_volume++; + spcl.c_type = TS_TAPE; + spcl.c_flags |= DR_NEWHEADER; + writeheader((ino_t)slp->inode); + spcl.c_flags &=~ DR_NEWHEADER; + if (tapeno > 1) + msg("Volume %d begins with blocks from inode %d\n", + tapeno, slp->inode); + } +} + +void +dumpabort(signo) + int signo; +{ + + if (master != 0 && master != getpid()) + /* Signals master to call dumpabort */ + (void) kill(master, SIGTERM); + else { + killall(); + msg("The ENTIRE dump is aborted.\n"); + } +#ifdef RDUMP + rmtclose(); +#endif + Exit(X_ABORT); +} + +__dead void +Exit(status) + int status; +{ + +#ifdef TDEBUG + msg("pid = %d exits with status %d\n", getpid(), status); +#endif /* TDEBUG */ + exit(status); +} + +/* + * proceed - handler for SIGUSR2, used to synchronize IO between the slaves. + */ +void +proceed(signo) + int signo; +{ + + if (ready) + longjmp(jmpbuf, 1); + caught++; +} + +void +enslave() +{ + int cmd[2]; + register int i, j; + + master = getpid(); + + signal(SIGTERM, dumpabort); /* Slave sends SIGTERM on dumpabort() */ + signal(SIGPIPE, sigpipe); + signal(SIGUSR1, tperror); /* Slave sends SIGUSR1 on tape errors */ + signal(SIGUSR2, proceed); /* Slave sends SIGUSR2 to next slave */ + + for (i = 0; i < SLAVES; i++) { + if (i == slp - &slaves[0]) { + caught = 1; + } else { + caught = 0; + } + + if (socketpair(AF_UNIX, SOCK_STREAM, 0, cmd) < 0 || + (slaves[i].pid = fork()) < 0) + quit("too many slaves, %d (recompile smaller): %s\n", + i, strerror(errno)); + + slaves[i].fd = cmd[1]; + slaves[i].sent = 0; + if (slaves[i].pid == 0) { /* Slave starts up here */ + for (j = 0; j <= i; j++) + (void) close(slaves[j].fd); + signal(SIGINT, SIG_IGN); /* Master handles this */ + doslave(cmd[0], i); + Exit(X_FINOK); + } + } + + for (i = 0; i < SLAVES; i++) + (void) atomic(write, slaves[i].fd, + (char *) &slaves[(i + 1) % SLAVES].pid, + sizeof slaves[0].pid); + + master = 0; +} + +void +killall() +{ + register int i; + + for (i = 0; i < SLAVES; i++) + if (slaves[i].pid > 0) + (void) kill(slaves[i].pid, SIGKILL); +} + +/* + * Synchronization - each process has a lockfile, and shares file + * descriptors to the following process's lockfile. When our write + * completes, we release our lock on the following process's lock- + * file, allowing the following process to lock it and proceed. We + * get the lock back for the next cycle by swapping descriptors. + */ +static void +doslave(cmd, slave_number) + register int cmd; + int slave_number; +{ + register int nread; + int nextslave, size, wrote, eot_count; + + /* + * Need our own seek pointer. + */ + (void) close(diskfd); + if ((diskfd = open(disk, O_RDONLY)) < 0) + quit("slave couldn't reopen disk: %s\n", strerror(errno)); + + /* + * Need the pid of the next slave in the loop... + */ + if ((nread = atomic(read, cmd, (char *)&nextslave, sizeof nextslave)) + != sizeof nextslave) { + quit("master/slave protocol botched - didn't get pid of next slave.\n"); + } + + /* + * Get list of blocks to dump, read the blocks into tape buffer + */ + while ((nread = atomic(read, cmd, (char *)slp->req, reqsiz)) == reqsiz) { + register struct req *p = slp->req; + + for (trecno = 0; trecno < ntrec; + trecno += p->count, p += p->count) { + if (p->dblk) { + bread(p->dblk, slp->tblock[trecno], + p->count * TP_BSIZE); + } else { + if (p->count != 1 || atomic(read, cmd, + (char *)slp->tblock[trecno], + TP_BSIZE) != TP_BSIZE) + quit("master/slave protocol botched.\n"); + } + } + if (setjmp(jmpbuf) == 0) { + ready = 1; + if (!caught) + (void) pause(); + } + ready = 0; + caught = 0; + + /* Try to write the data... */ + eot_count = 0; + size = 0; + + while (eot_count < 10 && size < writesize) { +#ifdef RDUMP + if (host) + wrote = rmtwrite(slp->tblock[0]+size, + writesize-size); + else +#endif + wrote = write(tapefd, slp->tblock[0]+size, + writesize-size); +#ifdef WRITEDEBUG + printf("slave %d wrote %d\n", slave_number, wrote); +#endif + if (wrote < 0) + break; + if (wrote == 0) + eot_count++; + size += wrote; + } + +#ifdef WRITEDEBUG + if (size != writesize) + printf("slave %d only wrote %d out of %d bytes and gave up.\n", + slave_number, size, writesize); +#endif + + if (eot_count > 0) + size = 0; + + /* + * fixme: Pyramids running OSx return ENOSPC + * at EOT on 1/2 inch drives. + */ + if (size < 0) { + (void) kill(master, SIGUSR1); + for (;;) + (void) sigpause(0); + } else { + /* + * pass size of write back to master + * (for EOT handling) + */ + (void) atomic(write, cmd, (char *)&size, sizeof size); + } + + /* + * If partial write, don't want next slave to go. + * Also jolts him awake. + */ + (void) kill(nextslave, SIGUSR2); + } + if (nread != 0) + quit("error reading command pipe: %s\n", strerror(errno)); +} + +/* + * Since a read from a pipe may not return all we asked for, + * or a write may not write all we ask if we get a signal, + * loop until the count is satisfied (or error). + */ +static int +atomic(func, fd, buf, count) + int (*func)(), fd; + char *buf; + int count; +{ + int got, need = count; + + while ((got = (*func)(fd, buf, need)) > 0 && (need -= got) > 0) + buf += got; + return (got < 0 ? got : count - need); +} |
