* 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
* 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
static char sccsid
[] = "@(#)tape.c 8.2 (Berkeley) 3/17/94";
#include <ufs/ufs/dinode.h>
#include <protocols/dumprestore.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 */
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.
#define SLAVES 3 /* 1 slave writing, 1 reading, 1 for slack */
int tapea
; /* header number at start of this chunk */
int count
; /* count to next header (used for TS_TAPE */
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 */
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 pgoff
= getpagesize() - 1;
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.
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
++) {
malloc((unsigned)(reqsiz
+ writesize
+ pgoff
+ TP_BSIZE
));
slaves
[i
].tblock
= (char (*)[TP_BSIZE
])
(((long)&buf
[ntrec
+ 1] + pgoff
) &~ pgoff
);
slaves
[i
].req
= (struct req
*)slaves
[i
].tblock
- ntrec
- 1;
slp
->req
[trecno
].dblk
= (daddr_t
)0;
slp
->req
[trecno
].count
= 1;
*(union u_spcl
*)(*(nextblock
)++) = *(union u_spcl
*)dp
;
lastspclrec
= spcl
.c_tapea
;
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
;
dblkno
+= avail
<< (tp_bshift
- dev_bshift
);
msg("write error on %s\n", tape
);
quit("Cannot recover\n");
msg("write error %d blocks into volume %d\n", blocksthisvol
, tapeno
);
broadcast("DUMP WRITE ERROR!\n");
if (!query("Do you want to restart?"))
msg("Closing this volume. Prepare to restart with new media;\n");
msg("this dump volume will be rewritten.\n");
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
])
/* Read results back from next slave */
if (atomic(read
, slp
->fd
, (char *)&got
, sizeof got
)
perror(" DUMP: error reading command pipe in master");
/* Check for end of tape */
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 (atomic(read
, slaves
[i
].fd
,
(char *)&got
, sizeof got
)
perror(" DUMP: error reading command pipe in master");
if (spcl
.c_type
!= TS_END
) {
for (i
= 0; i
< spcl
.c_count
; i
++)
slp
->count
= lastspclrec
+ blks
+ 1 - spcl
.c_tapea
;
slp
->tapea
= spcl
.c_tapea
;
slp
->firstrec
= lastfirstrec
+ ntrec
;
if (!pipeout
&& (blocksperfile
?
(blocksthisvol
>= blocksperfile
) : (asize
> tsize
))) {
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.
if (atomic(read
, slaves
[f
].fd
, (char *)&got
, sizeof got
)
perror(" DUMP: error reading command pipe in master");
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 */
msg("Closing %s\n", tape
);
while (rmtopen(tape
, 0) < 0)
while ((f
= open(tape
, 0)) < 0)
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?")) {
register struct req
*p
, *q
, *prev
;
register struct slave
*tslp
;
int i
, size
, savedtapea
, got
;
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
for (i
= 0; i
< SLAVES
; i
++) {
otb
= (union u_spcl
*)slp
->tblock
;
* For each request in the current slave, copy it to tslp.
for (p
= slp
->req
; p
->count
> 0; p
+= p
->count
) {
*ntb
++ = *otb
++; /* copy the datablock also */
quit("rollforward: protocol botch");
nextblock
= tslp
->tblock
;
savedtapea
= spcl
.c_tapea
;
spcl
.c_tapea
= slp
->tapea
;
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");
if (++slp
>= &slaves
[SLAVES
])
* If the last one was a disk block, make the
* first of this one be the last bit of that disk
prev
->count
* (TP_BSIZE
/ DEV_BSIZE
);
ntb
= (union u_spcl
*)tslp
->tblock
;
* It wasn't a disk block. Copy the data to its
* new location in the buffer.
*((union u_spcl
*)tslp
->tblock
) = *ntb
;
ntb
= (union u_spcl
*)tslp
->tblock
[1];
* Clear the first slaves' response. One hopes that it
* worked ok, otherwise the tape is much too short!
if (atomic(read
, slp
->fd
, (char *)&got
, sizeof got
)
perror(" DUMP: error reading command pipe in master");
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 (*interrupt_save
)();
interrupt_save
= signal(SIGINT
, SIG_IGN
);
(void)signal(SIGINT
, interrupt_save
);
* All signals are inherited...
msg("Context save fork fails in parent %d\n", parentpid
);
* save the context by waiting
* until the child doing all of the work returns.
* don't catch the interrupt
msg("Tape: %d; parent process: %d child process %d\n",
tapeno
+1, parentpid
, childpid
);
while ((waitpid
= wait(&status
)) != childpid
)
msg("Parent %d waiting for child %d has another child %d return\n",
parentpid
, childpid
, waitpid
);
msg("Child %d returns LOB status %o\n",
status
= (status
>> 8) & 0xFF;
msg("Child %d finishes X_FINOK\n", childpid
);
msg("Child %d finishes X_ABORT\n", childpid
);
msg("Child %d finishes X_REWRITE\n", childpid
);
msg("Child %d finishes unknown %d\n",
goto restore_check_point
;
msg("Bad return code from dump: %d\n", status
);
} else { /* we are the child; just continue */
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());
* 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
)
if ((p
= index(tape
, ',')) != NULL
) {
msg("Dumping volume %d on %s\n", tapeno
, tape
);
while ((tapefd
= (host
? rmtopen(tape
, 2) :
pipeout
? 1 : open(tape
, O_WRONLY
|O_CREAT
, 0666))) < 0)
while ((tapefd
= (pipeout
? 1 :
open(tape
, O_WRONLY
|O_CREAT
, 0666))) < 0)
msg("Cannot open output \"%s\".\n", tape
);
if (!query("Do you want to retry the open?"))
enslave(); /* Share open tape file descriptor with slaves */
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_flags
|= DR_NEWHEADER
;
writeheader((ino_t
)slp
->inode
);
spcl
.c_flags
&=~ DR_NEWHEADER
;
msg("Volume %d begins with blocks from inode %d\n",
if (master
!= 0 && master
!= getpid())
/* Signals master to call dumpabort */
(void) kill(master
, SIGTERM
);
msg("The ENTIRE dump is aborted.\n");
msg("pid = %d exits with status %d\n", getpid(), status
);
* proceed - handler for SIGUSR2, used to synchronize IO between the slaves.
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]) {
if (socketpair(AF_UNIX
, SOCK_STREAM
, 0, cmd
) < 0 ||
(slaves
[i
].pid
= fork()) < 0)
quit("too many slaves, %d (recompile smaller): %s\n",
if (slaves
[i
].pid
== 0) { /* Slave starts up here */
(void) close(slaves
[j
].fd
);
signal(SIGINT
, SIG_IGN
); /* Master handles this */
for (i
= 0; i
< SLAVES
; i
++)
(void) atomic(write
, slaves
[i
].fd
,
(char *) &slaves
[(i
+ 1) % SLAVES
].pid
,
for (i
= 0; i
< SLAVES
; i
++)
(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.
doslave(cmd
, slave_number
)
int nextslave
, size
, wrote
, eot_count
;
* Need our own seek pointer.
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
))
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
) {
bread(p
->dblk
, slp
->tblock
[trecno
],
if (p
->count
!= 1 || atomic(read
, cmd
,
(char *)slp
->tblock
[trecno
],
quit("master/slave protocol botched.\n");
if (setjmp(jmpbuf
) == 0) {
/* Try to write the data... */
while (eot_count
< 10 && size
< writesize
) {
wrote
= rmtwrite(slp
->tblock
[0]+size
,
wrote
= write(tapefd
, slp
->tblock
[0]+size
,
printf("slave %d wrote %d\n", slave_number
, wrote
);
printf("slave %d only wrote %d out of %d bytes and gave up.\n",
slave_number
, size
, writesize
);
* fixme: Pyramids running OSx return ENOSPC
* at EOT on 1/2 inch drives.
(void) kill(master
, SIGUSR1
);
* pass size of write back to master
(void) atomic(write
, cmd
, (char *)&size
, sizeof size
);
* If partial write, don't want next slave to go.
(void) kill(nextslave
, SIGUSR2
);
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).
atomic(func
, fd
, buf
, count
)
while ((got
= (*func
)(fd
, buf
, need
)) > 0 && (need
-= got
) > 0)
return (got
< 0 ? got
: count
- need
);