2.9BSD/usr/net/sys/dev/tm.c
/*
* SCCS id @(#)tm.c 2.1 (Berkeley) 8/5/83
*/
#include "tm.h"
#if NTM > 0
#include "param.h"
#include <sys/buf.h>
#include <sys/dir.h>
#include <sys/conf.h>
#include <sys/file.h>
#include <sys/user.h>
#include <sys/systm.h>
#include <sys/tmreg.h>
#ifdef TM_IOCTL
#include <sys/mtio.h>
#endif
struct tmdevice *TMADDR;
struct buf tmtab;
struct buf ctmbuf;
/*
* Raw tape operations use rtmbuf. The driver
* notices when rtmbuf is being used and allows the user
* program to continue after errors and read records
* not of the standard length (BSIZE).
*/
struct buf rtmbuf;
/*
* Software state per tape transport:
*
* 1. A tape drive is a unique-open device: we refuse opens when it is already.
* 2. We keep track of the current position on a block tape and seek
* before operations by forward/back spacing if necessary.
* 3. We remember if the last operation was a write on a tape, so if a tape
* is open read write and the last thing done is a write we can
* write a standard end of tape mark (two eofs).
* 4. We remember the status registers after the last command, using
* them internally and returning them to the SENSE ioctl.
* 5. We remember the last density the tape was used at. If it is
* not a BOT when we start using it and we are writing, we don't
* let the density be changed.
*/
struct te_softc {
char sc_openf;
char sc_lastiow;
daddr_t sc_blkno;
daddr_t sc_nxrec;
u_short sc_erreg;
#ifdef TM_IOCTL
u_short sc_dsreg;
short sc_resid;
#endif
u_short sc_dens;
#ifdef TM_TIMEOUT
short sc_timo;
short sc_tact;
#endif
} te_softc[NTM];
/*
* States for tmtab.b_active, the state flag.
* This is used to sequence control in the driver.
*/
#define SSEEK 1
#define SIO 2
#define SCOM 3
#define SREW 4
#define TEUNIT(dev) (minor(dev) & 077)
/* bits in minor device */
#define T_1600BPI 0100
#define T_NOREWIND 0200
#define INF 32760
#ifdef TM_TIMEOUT
int tmtimer ();
#endif
tmattach(addr, unit)
struct tmdevice *addr;
{
/*
* This driver supports only one controller.
*/
if (unit == 0) {
TMADDR = addr;
return(1);
}
return(0);
}
/*
* Open the device. Tapes are unique open
* devices so we refuse if it is alredy open.
* We also check that the tape is available and
* don't block waiting here: if you want to wait
* for a tape you should timeout in user code.
*/
tmopen(dev, flag)
register dev_t dev;
{
int s;
u_short olddens, dens;
register teunit = TEUNIT(dev);
register struct te_softc *sc = &te_softc[teunit];
if (teunit >= NTM || TMADDR == (struct tmdevice *) NULL) {
u.u_error = ENXIO;
return;
}
else
if (sc->sc_openf) {
u.u_error = EBUSY;
return;
}
olddens = sc->sc_dens;
#ifdef DDMT
dens = TM_IE | TM_GO | (teunit << 8);
if ((minor(dev) & T_1600BPI) == 0)
dens |= TM_D800;
#else
dens = TM_IE | TM_GO | TM_D800 | (teunit << 8);
#endif
sc->sc_dens = dens;
tmtab.b_flags |= B_TAPE;
get:
tmcommand(dev, TM_SENSE, 1);
if (sc->sc_erreg & TMER_SDWN) {
sleep ((caddr_t) &lbolt, PZERO+1);
goto get;
}
sc->sc_dens = olddens;
if ((sc->sc_erreg & (TMER_SELR | TMER_TUR)) != (TMER_SELR | TMER_TUR)) {
uprintf("te%d: not online\n", teunit);
u.u_error = EIO;
return;
}
if ((flag & FWRITE) && (sc->sc_erreg & TMER_WRL)) {
uprintf("te%d: no write ring\n", teunit);
u.u_error = EIO;
return;
}
#ifdef DDMT
if ((sc->sc_erreg & TMER_BOT) == 0 && (flag & FWRITE) && dens != sc->sc_dens) {
uprintf("te%d: can't change density in mid-tape\n", teunit);
u.u_error = EIO;
return;
}
#endif
sc->sc_openf = 1;
sc->sc_blkno = (daddr_t) 0;
sc->sc_nxrec = (daddr_t) 65535;
sc->sc_lastiow = 0;
sc->sc_dens = dens;
#ifdef TM_TIMEOUT
s = spl6();
if (sc->sc_tact == 0) {
sc->sc_timo = INF;
sc->sc_tact = 1;
timeout(tmtimer, (caddr_t) dev, 5 * hz);
}
splx(s);
#endif
}
/*
* Close tape device.
*
* If tape was open for writing or last operation was
* a write, then write two EOF's and backspace over the last one.
* Unless this is a non-rewinding special file, rewind the tape.
* Make the tape available to others.
*/
tmclose(dev, flag)
register dev_t dev;
register flag;
{
register struct te_softc *sc = &te_softc[TEUNIT(dev)];
if (flag == FWRITE || (flag & FWRITE) && sc->sc_lastiow) {
tmcommand(dev, TM_WEOF, 1);
tmcommand(dev, TM_WEOF, 1);
tmcommand(dev, TM_SREV, 1);
}
if ((minor(dev) & T_NOREWIND) == 0)
/*
* 0 count means don't hang waiting for rewind complete.
* Rather ctmbuf stays busy until the operation completes
* preventing further opens from completing by
* preventing a TM_SENSE from completing.
*/
tmcommand(dev, TM_REW, 0);
sc->sc_openf = 0;
}
/*
* Execute a command on the tape drive
* a specified number of times.
*/
tmcommand(dev, com, count)
register dev_t dev;
register u_short count;
{
int s;
register struct buf *bp;
bp = &ctmbuf;
s = spl5();
while (bp->b_flags & B_BUSY) {
/*
* This special check is because B_BUSY never
* gets cleared in the non-waiting rewind case.
*/
if (bp->b_repcnt == 0 && (bp->b_flags & B_DONE))
break;
bp->b_flags |= B_WANTED;
sleep((caddr_t)bp, PRIBIO);
}
bp->b_flags = B_BUSY | B_READ;
splx(s);
bp->b_dev = dev;
bp->b_repcnt = -count;
bp->b_command = com;
bp->b_blkno = (daddr_t) 0;
tmstrategy(bp);
/*
* In case of rewind from close, don't wait.
* This is the only case where count can be 0.
*/
if (count == 0)
return;
iowait(bp);
if (bp->b_flags & B_WANTED)
wakeup((caddr_t)bp);
bp->b_flags &= B_ERROR;
}
/*
* Queue a tape operation.
*/
tmstrategy(bp)
register struct buf *bp;
{
register s;
#ifdef UNIBUS_MAP
if (bp != &ctmbuf)
mapalloc(bp);
#endif
bp->av_forw = NULL;
s = spl5();
if (tmtab.b_actf == NULL)
tmtab.b_actf = bp;
else
tmtab.b_actl->av_forw = bp;
tmtab.b_actl = bp;
/*
* If the controller is not busy, get
* it going.
*/
if (tmtab.b_active == 0)
tmstart();
splx(s);
}
tmstart()
{
daddr_t blkno;
int cmd, teunit;
register struct tmdevice *tmaddr = TMADDR;
register struct buf *bp;
register struct te_softc *sc;
loop:
if ((bp = tmtab.b_actf) == NULL)
return;
teunit = TEUNIT(bp->b_dev);
/*
* Record pre-transfer status (e.g. for TM_SENSE).
*/
sc = &te_softc[teunit];
tmaddr->tmcs = teunit << 8;
sc->sc_erreg = tmaddr->tmer;
#ifdef TM_IOCTL
sc->sc_dsreg = tmaddr->tmcs;
sc->sc_resid = tmaddr->tmbc;
#endif
/*
* Default is that the last command was NOT a write command;
* if we do a write command we will notice this in tmintr().
*/
sc->sc_lastiow = 0;
if (sc->sc_openf < 0 || (tmaddr->tmcs & TM_CUR) == 0) {
/*
* Have had a hard error on a non-raw tape
* or the tape unit is now unavailable
* (e.g. taken off line).
*/
bp->b_flags |= B_ERROR;
goto next;
}
if (bp == &ctmbuf) {
/*
* Execute control operation with the specified count.
*/
if (bp->b_command == TM_SENSE) {
goto next;
}
#ifdef TM_TIMEOUT
/*
* Set next state; give 5 minutes to complete
* rewind or 10 seconds per iteration (minimum 60
* seconds and max 5 minutes) to complete other ops.
*/
#else
/*
* Set next state.
*/
#endif
if (bp->b_command == TM_REW) {
tmtab.b_active = SREW;
#ifdef TM_TIMEOUT
sc->sc_timo = 5 * 60;
#endif
} else {
tmtab.b_active = SCOM;
#ifdef TM_TIMEOUT
sc->sc_timo = MIN(MAX(10 * bp->b_repcnt, 60), 5 * 60);
#endif
}
if (bp->b_command == TM_SFORW || bp->b_command == TM_SREV)
tmaddr->tmbc = bp->b_repcnt;
goto dobpcmd;
}
/*
* The following checks handle boundary cases for operation
* on non-raw tapes. On raw tapes the initialization of
* sc->sc_nxrec by tmphys causes them to be skipped normally
* (except in the case of retries).
*/
if (dbtofsb(bp->b_blkno) > sc->sc_nxrec) {
/*
* Can't read past known end-of-file.
*/
bp->b_flags |= B_ERROR;
bp->b_error = ENXIO;
goto next;
}
if (dbtofsb(bp->b_blkno) == sc->sc_nxrec && bp->b_flags & B_READ) {
/*
* Reading at end of file returns 0 bytes.
* Buffer will be cleared (if written) in writei.
*/
bp->b_resid = bp->b_bcount;
goto next;
}
if ((bp->b_flags & B_READ) == 0)
/*
* Writing sets EOF.
*/
sc->sc_nxrec = dbtofsb(bp->b_blkno) + (daddr_t) 1;
/*
* If the data transfer command is in the correct place,
* set up all registers and do the transfer.
*/
if ((blkno = sc->sc_blkno) == dbtofsb(bp->b_blkno)) {
tmaddr->tmbc = -bp->b_bcount;
if ((bp->b_flags & B_READ) == 0) {
if (tmtab.b_errcnt)
cmd = TM_WIRG;
else
cmd = TM_WCOM;
} else
cmd = TM_RCOM;
tmtab.b_active = SIO;
tmaddr->tmba = bp->b_un.b_addr;
cmd = sc->sc_dens | ((bp->b_xmem & 03) << 4) | cmd;
#ifdef TM_TIMEOUT
sc->sc_timo = 60; /* premature, but should serve */
#endif
tmaddr->tmcs = cmd;
return;
}
/*
* Tape positioned incorrectly;
* set to seek forward or backward to the correct spot.
* This happens for raw tapes only on error retries.
*/
tmtab.b_active = SSEEK;
if (blkno < dbtofsb(bp->b_blkno)) {
bp->b_command = TM_SFORW;
tmaddr->tmbc = (short) (blkno - dbtofsb(bp->b_blkno));
} else {
bp->b_command = TM_SREV;
tmaddr->tmbc = (short) (dbtofsb(bp->b_blkno) - blkno);
}
#ifdef TM_TIMEOUT
sc->sc_timo = MIN(MAX(10 * -tmaddr->tmbc, 60), 5 * 60);
#endif
dobpcmd:
/*
* Do the command in bp.
*/
tmaddr->tmcs = (sc->sc_dens | bp->b_command);
return;
next:
/*
* Done with this operation due to error or
* the fact that it doesn't do anything.
* Dequeue the transfer and continue processing.
*/
tmtab.b_errcnt = 0;
tmtab.b_actf = bp->av_forw;
iodone(bp);
goto loop;
}
/*
* The interrupt routine.
*/
tmintr()
{
register struct tmdevice *tmaddr = TMADDR;
register struct buf *bp;
int teunit;
int state;
register struct te_softc *sc;
if ((bp = tmtab.b_actf) == NULL)
return;
teunit = TEUNIT(bp->b_dev);
sc = &te_softc[teunit];
/*
* If last command was a rewind, and tape is still
* rewinding, wait for the rewind complete interrupt.
*/
if (tmtab.b_active == SREW) {
tmtab.b_active = SCOM;
if (tmaddr->tmer & TMER_RWS) {
#ifdef TM_TIMEOUT
sc->sc_timo = 5 * 60; /* 5 minutes */
#endif
return;
}
}
/*
* An operation completed... record status.
*/
#ifdef TM_TIMEOUT
sc->sc_timo = INF;
#endif
sc->sc_erreg = tmaddr->tmer;
#ifdef TM_IOCTL
sc->sc_dsreg = tmaddr->tmcs;
sc->sc_resid = tmaddr->tmbc;
#endif
if ((bp->b_flags & B_READ) == 0)
sc->sc_lastiow = 1;
state = tmtab.b_active;
tmtab.b_active = 0;
/*
* Check for errors.
*/
if (tmaddr->tmcs & TM_ERR) {
while(tmaddr->tmer & TMER_SDWN)
; /* await settle down */
/*
* If we hit the end of the tape file, update our position.
*/
if (tmaddr->tmer & TMER_EOF) {
tmseteof(bp); /* set blkno and nxrec */
state = SCOM; /* force completion */
/*
* Stuff bc so it will be unstuffed correctly
* later to get resid.
*/
tmaddr->tmbc = -bp->b_bcount;
goto opdone;
}
/*
* If we were reading raw tape and the only error was that the
* record was too long, then we don't consider this an error.
*/
if (bp == &rtmbuf && (bp->b_flags & B_READ) &&
(tmaddr->tmer & (TMER_HARD | TMER_SOFT)) == TMER_RLE)
goto ignoreerr;
/*
* If error is not hard, and this was an i/o operation
* retry up to 8 times.
*/
if ((tmaddr->tmer & TMER_HARD) == 0 && state == SIO) {
if (++tmtab.b_errcnt < 7) {
sc->sc_blkno++;
goto opcont;
}
} else
/*
* Hard or non-i/o errors on non-raw tape
* cause it to close.
*/
if (sc->sc_openf > 0 && bp != &rtmbuf)
sc->sc_openf = -1;
/*
* Couldn't recover error
*/
#ifdef UCB_DEVERR
printf("te%d: hard error bn%D er=%b\n",
teunit, bp->b_blkno, sc->sc_erreg, TMER_BITS);
#else
deverror(bp, sc->sc_erreg, 0);
#endif
bp->b_flags |= B_ERROR;
goto opdone;
}
/*
* Advance tape control finite state machine.
*/
ignoreerr:
switch (state) {
case SIO:
/*
* Read/write increments tape block number.
*/
sc->sc_blkno++;
goto opdone;
case SCOM:
/*
* For forward/backward space record update current position.
*/
if (bp == &ctmbuf)
switch (bp->b_command) {
case TM_SFORW:
sc->sc_blkno -= (daddr_t) (bp->b_repcnt);
break;
case TM_SREV:
sc->sc_blkno += (daddr_t) (bp->b_repcnt);
break;
}
goto opdone;
case SSEEK:
sc->sc_blkno = dbtofsb(bp->b_blkno);
goto opcont;
default:
panic("tmintr");
}
opdone:
/*
* Reset error count and remove
* from device queue.
*/
tmtab.b_errcnt = 0;
tmtab.b_actf = bp->av_forw;
bp->b_resid = -tmaddr->tmbc;
iodone(bp);
opcont:
tmstart();
}
#ifdef TM_TIMEOUT
tmtimer(dev)
register dev_t dev;
{
register s;
register struct te_softc *sc = &te_softc[TEUNIT(dev)];
if (sc->sc_timo != INF && (sc->sc_timo -= 5) < 0) {
printf("te%d: lost interrupt\n", TEUNIT(dev));
sc->sc_timo = INF;
s = spl5();
tmintr();
splx(s);
}
timeout(tmtimer, (caddr_t) dev, 5 * hz);
}
#endif
tmseteof(bp)
register struct buf *bp;
{
register struct tmdevice *tmaddr = TMADDR;
daddr_t bn = dbtofsb(bp->b_blkno);
register struct te_softc *sc = &te_softc[TEUNIT(bp->b_dev)];
if (bp == &ctmbuf) {
if (sc->sc_blkno > bn) {
/* reversing */
sc->sc_nxrec = bn - (daddr_t) (tmaddr->tmbc);
sc->sc_blkno = sc->sc_nxrec;
} else {
/* spacing forward */
sc->sc_blkno = bn + (daddr_t) (tmaddr->tmbc);
sc->sc_nxrec = sc->sc_blkno - (daddr_t) 1;
}
return;
}
/* eof on read */
sc->sc_nxrec = bn;
}
tmread(dev)
register dev_t dev;
{
tmphys(dev);
bphysio(tmstrategy, &rtmbuf, dev, B_READ);
}
tmwrite(dev)
register dev_t dev;
{
tmphys(dev);
bphysio(tmstrategy, &rtmbuf, dev, B_WRITE);
}
/*
* Set up sc_blkno and sc_nxrec
* so that the tape will appear positioned correctly.
*/
tmphys(dev)
dev_t dev;
{
daddr_t a;
register struct te_softc *sc = &te_softc[TEUNIT(dev)];
a = dbtofsb(u.u_offset >> 9);
sc->sc_blkno = a;
sc->sc_nxrec = a + 1;
}
#ifdef TM_IOCTL
/*ARGSUSED*/
tmioctl(dev, cmd, addr, flag)
dev_t dev;
caddr_t addr;
{
register struct buf *bp = &ctmbuf;
register struct te_softc *sc = &te_softc[TEUNIT(dev)];
register callcount;
u_short fcount;
struct mtop mtop;
struct mtget mtget;
/* we depend on the values and order of the MT codes here */
static tmops[] = {TM_WEOF,TM_SFORW,TM_SREV,TM_SFORW,TM_SREV,TM_REW,TM_OFFL,TM_SENSE};
switch (cmd) {
case MTIOCTOP: /* tape operation */
if (copyin((caddr_t)addr, (caddr_t)&mtop, sizeof(mtop))) {
u.u_error = EFAULT;
return;
}
switch(mtop.mt_op) {
case MTWEOF:
callcount = mtop.mt_count;
fcount = 1;
break;
case MTFSF:
case MTBSF:
callcount = mtop.mt_count;
fcount = INF;
break;
case MTFSR:
case MTBSR:
callcount = 1;
fcount = mtop.mt_count;
break;
case MTREW:
case MTOFFL:
case MTNOP:
callcount = 1;
fcount = 1;
break;
default:
u.u_error = ENXIO;
return;
}
if (callcount <= 0 || fcount <= 0) {
u.u_error = ENXIO;
return;
}
while (--callcount >= 0) {
tmcommand(dev, tmops[mtop.mt_op], fcount);
if ((mtop.mt_op == MTFSR || mtop.mt_op == MTBSR) &&
bp->b_resid) {
u.u_error = EIO;
break;
}
if ((bp->b_flags & B_ERROR) || sc->sc_erreg & TMER_BOT)
break;
}
geterror(bp);
return;
case MTIOCGET:
mtget.mt_erreg = sc->sc_erreg;
mtget.mt_dsreg = sc->sc_dsreg;
mtget.mt_resid = sc->sc_resid;
mtget.mt_type = MT_ISTM;
if (copyout((caddr_t)&mtget, addr, sizeof(mtget)))
u.u_error = EFAULT;
return;
default:
u.u_error = ENXIO;
}
}
#endif
#endif NTM