2.9BSD - /usr/src/sys/dev/tm.c

   1: /*
   2:  *	SCCS id	@(#)tm.c	2.1 (Berkeley)	8/5/83
   3:  */
   4: 
   5: #include "tm.h"
   6: #if NTM > 0
   7: #include "param.h"
   8: #include <sys/buf.h>
   9: #include <sys/dir.h>
  10: #include <sys/conf.h>
  11: #include <sys/file.h>
  12: #include <sys/user.h>
  13: #include <sys/systm.h>
  14: #include <sys/tmreg.h>
  15: #ifdef  TM_IOCTL
  16: #include <sys/mtio.h>
  17: #endif
  18: 
  19: struct  tmdevice *TMADDR;
  20: 
  21: struct  buf tmtab;
  22: struct  buf ctmbuf;
  23: /*
  24:  * Raw tape operations use rtmbuf.  The driver
  25:  * notices when rtmbuf is being used and allows the user
  26:  * program to continue after errors and read records
  27:  * not of the standard length (BSIZE).
  28:  */
  29: struct  buf rtmbuf;
  30: 
  31: /*
  32:  * Software state per tape transport:
  33:  *
  34:  * 1. A tape drive is a unique-open device:  we refuse opens when it is already.
  35:  * 2. We keep track of the current position on a block tape and seek
  36:  *    before operations by forward/back spacing if necessary.
  37:  * 3. We remember if the last operation was a write on a tape, so if a tape
  38:  *    is open read write and the last thing done is a write we can
  39:  *    write a standard end of tape mark (two eofs).
  40:  * 4. We remember the status registers after the last command, using
  41:  *    them internally and returning them to the SENSE ioctl.
  42:  * 5. We remember the last density the tape was used at.  If it is
  43:  *    not a BOT when we start using it and we are writing, we don't
  44:  *    let the density be changed.
  45:  */
  46: 
  47: struct te_softc {
  48:     char    sc_openf;
  49:     char    sc_lastiow;
  50:     daddr_t sc_blkno;
  51:     daddr_t sc_nxrec;
  52:     u_short sc_erreg;
  53: #ifdef  TM_IOCTL
  54:     u_short sc_dsreg;
  55:     short   sc_resid;
  56: #endif
  57:     u_short sc_dens;
  58: #ifdef  TM_TIMEOUT
  59:     short   sc_timo;
  60:     short   sc_tact;
  61: #endif
  62: } te_softc[NTM];
  63: 
  64: 
  65: /*
  66:  * States for tmtab.b_active, the state flag.
  67:  * This is used to sequence control in the driver.
  68:  */
  69: #define SSEEK   1
  70: #define SIO 2
  71: #define SCOM    3
  72: #define SREW    4
  73: 
  74: #define TEUNIT(dev) (minor(dev) & 077)
  75: 
  76: /* bits in minor device */
  77: #define T_1600BPI   0100
  78: #define T_NOREWIND  0200
  79: 
  80: #define INF 32760
  81: 
  82: #ifdef  TM_TIMEOUT
  83: int tmtimer ();
  84: #endif
  85: 
  86: tmattach(addr, unit)
  87: struct tmdevice *addr;
  88: {
  89:     /*
  90: 	 * This driver supports only one controller.
  91: 	 */
  92:     if (unit == 0) {
  93:         TMADDR = addr;
  94:         return(1);
  95:     }
  96:     return(0);
  97: }
  98: 
  99: /*
 100:  * Open the device.  Tapes are unique open
 101:  * devices so we refuse if it is alredy open.
 102:  * We also check that the tape is available and
 103:  * don't block waiting here:  if you want to wait
 104:  * for a tape you should timeout in user code.
 105:  */
 106: tmopen(dev, flag)
 107: register dev_t dev;
 108: {
 109:     int s;
 110:     u_short olddens, dens;
 111:     register teunit = TEUNIT(dev);
 112:     register struct te_softc *sc = &te_softc[teunit];
 113: 
 114:     if (teunit >= NTM || TMADDR == (struct tmdevice *) NULL) {
 115:         u.u_error = ENXIO;
 116:         return;
 117:     }
 118:     else
 119:         if (sc->sc_openf) {
 120:             u.u_error = EBUSY;
 121:             return;
 122:         }
 123:     olddens = sc->sc_dens;
 124: #ifdef  DDMT
 125:     dens = TM_IE | TM_GO | (teunit << 8);
 126:     if ((minor(dev) & T_1600BPI) == 0)
 127:         dens |= TM_D800;
 128: #else
 129:     dens = TM_IE | TM_GO | TM_D800 | (teunit << 8);
 130: #endif
 131:     sc->sc_dens = dens;
 132: 
 133:     tmtab.b_flags |= B_TAPE;
 134: get:
 135:     tmcommand(dev, TM_SENSE, 1);
 136:     if (sc->sc_erreg & TMER_SDWN) {
 137:         sleep ((caddr_t) &lbolt, PZERO+1);
 138:         goto get;
 139:     }
 140:     sc->sc_dens = olddens;
 141: 
 142:     if ((sc->sc_erreg & (TMER_SELR | TMER_TUR)) != (TMER_SELR | TMER_TUR)) {
 143:         uprintf("te%d: not online\n", teunit);
 144:         u.u_error = EIO;
 145:         return;
 146:     }
 147:     if ((flag & FWRITE) && (sc->sc_erreg & TMER_WRL)) {
 148:         uprintf("te%d: no write ring\n", teunit);
 149:         u.u_error = EIO;
 150:         return;
 151:     }
 152: #ifdef  DDMT
 153:     if ((sc->sc_erreg & TMER_BOT) == 0 && (flag & FWRITE) && dens != sc->sc_dens) {
 154:         uprintf("te%d: can't change density in mid-tape\n", teunit);
 155:         u.u_error = EIO;
 156:         return;
 157:     }
 158: #endif
 159:     sc->sc_openf = 1;
 160:     sc->sc_blkno = (daddr_t) 0;
 161:     sc->sc_nxrec = (daddr_t) 65535;
 162:     sc->sc_lastiow = 0;
 163:     sc->sc_dens = dens;
 164: #ifdef  TM_TIMEOUT
 165:     s = spl6();
 166:     if (sc->sc_tact == 0) {
 167:         sc->sc_timo = INF;
 168:         sc->sc_tact = 1;
 169:         timeout(tmtimer, (caddr_t) dev, 5 * hz);
 170:     }
 171:     splx(s);
 172: #endif
 173: }
 174: 
 175: /*
 176:  * Close tape device.
 177:  *
 178:  * If tape was open for writing or last operation was
 179:  * a write, then write two EOF's and backspace over the last one.
 180:  * Unless this is a non-rewinding special file, rewind the tape.
 181:  * Make the tape available to others.
 182:  */
 183: tmclose(dev, flag)
 184: register dev_t dev;
 185: register flag;
 186: {
 187:     register struct te_softc *sc = &te_softc[TEUNIT(dev)];
 188: 
 189:     if (flag == FWRITE || (flag & FWRITE) && sc->sc_lastiow) {
 190:         tmcommand(dev, TM_WEOF, 1);
 191:         tmcommand(dev, TM_WEOF, 1);
 192:         tmcommand(dev, TM_SREV, 1);
 193:     }
 194:     if ((minor(dev) & T_NOREWIND) == 0)
 195:         /*
 196: 		 * 0 count means don't hang waiting for rewind complete.
 197: 		 * Rather ctmbuf stays busy until the operation completes
 198: 		 * preventing further opens from completing by
 199: 		 * preventing a TM_SENSE from completing.
 200: 		 */
 201:         tmcommand(dev, TM_REW, 0);
 202:     sc->sc_openf = 0;
 203: }
 204: 
 205: /*
 206:  * Execute a command on the tape drive
 207:  * a specified number of times.
 208:  */
 209: tmcommand(dev, com, count)
 210: register dev_t dev;
 211: register u_short count;
 212: {
 213:     int s;
 214:     register struct buf *bp;
 215: 
 216:     bp = &ctmbuf;
 217:     s = spl5();
 218:     while (bp->b_flags & B_BUSY) {
 219:         /*
 220: 		 * This special check is because B_BUSY never
 221: 		 * gets cleared in the non-waiting rewind case.
 222: 		 */
 223:         if (bp->b_repcnt == 0 && (bp->b_flags & B_DONE))
 224:             break;
 225:         bp->b_flags |= B_WANTED;
 226:         sleep((caddr_t)bp, PRIBIO);
 227:     }
 228:     bp->b_flags = B_BUSY | B_READ;
 229:     splx(s);
 230:     bp->b_dev = dev;
 231:     bp->b_repcnt = -count;
 232:     bp->b_command = com;
 233:     bp->b_blkno = (daddr_t) 0;
 234:     tmstrategy(bp);
 235:     /*
 236: 	 * In case of rewind from close, don't wait.
 237: 	 * This is the only case where count can be 0.
 238: 	 */
 239:     if (count == 0)
 240:         return;
 241:     iowait(bp);
 242:     if (bp->b_flags & B_WANTED)
 243:         wakeup((caddr_t)bp);
 244:     bp->b_flags &= B_ERROR;
 245: }
 246: 
 247: /*
 248:  * Queue a tape operation.
 249:  */
 250: tmstrategy(bp)
 251: register struct buf *bp;
 252: {
 253:     register s;
 254: 
 255: #ifdef UNIBUS_MAP
 256:     if (bp != &ctmbuf)
 257:         mapalloc(bp);
 258: #endif
 259:     bp->av_forw = NULL;
 260:     s = spl5();
 261:     if (tmtab.b_actf == NULL)
 262:         tmtab.b_actf = bp;
 263:     else
 264:         tmtab.b_actl->av_forw = bp;
 265:     tmtab.b_actl = bp;
 266:     /*
 267: 	 * If the controller is not busy, get
 268: 	 * it going.
 269: 	 */
 270:     if (tmtab.b_active == 0)
 271:         tmstart();
 272:     splx(s);
 273: }
 274: 
 275: tmstart()
 276: {
 277:     daddr_t blkno;
 278:     int cmd, teunit;
 279:     register struct tmdevice *tmaddr = TMADDR;
 280:     register struct buf *bp;
 281:     register struct te_softc *sc;
 282: 
 283: loop:
 284:     if ((bp = tmtab.b_actf) == NULL)
 285:         return;
 286:     teunit = TEUNIT(bp->b_dev);
 287:     /*
 288: 	 * Record pre-transfer status (e.g. for TM_SENSE).
 289: 	 */
 290:     sc = &te_softc[teunit];
 291:     tmaddr->tmcs = teunit << 8;
 292:     sc->sc_erreg = tmaddr->tmer;
 293: #ifdef  TM_IOCTL
 294:     sc->sc_dsreg = tmaddr->tmcs;
 295:     sc->sc_resid = tmaddr->tmbc;
 296: #endif
 297:     /*
 298: 	 * Default is that the last command was NOT a write command;
 299: 	 * if we do a write command we will notice this in tmintr().
 300: 	 */
 301:     sc->sc_lastiow = 0;
 302:     if (sc->sc_openf < 0 || (tmaddr->tmcs & TM_CUR) == 0) {
 303:         /*
 304: 		 * Have had a hard error on a non-raw tape
 305: 		 * or the tape unit is now unavailable
 306: 		 * (e.g. taken off line).
 307: 		 */
 308:         bp->b_flags |= B_ERROR;
 309:         goto next;
 310:     }
 311:     if (bp == &ctmbuf) {
 312:         /*
 313: 		 * Execute control operation with the specified count.
 314: 		 */
 315:         if (bp->b_command == TM_SENSE) {
 316:             goto next;
 317:         }
 318: #ifdef  TM_TIMEOUT
 319:         /*
 320: 		 * Set next state; give 5 minutes to complete
 321: 		 * rewind or 10 seconds per iteration (minimum 60
 322: 		 * seconds and max 5 minutes) to complete other ops.
 323: 		 */
 324: #else
 325:         /*
 326: 		 * Set next state.
 327: 		 */
 328: #endif
 329:         if (bp->b_command == TM_REW) {
 330:             tmtab.b_active = SREW;
 331: #ifdef  TM_TIMEOUT
 332:             sc->sc_timo = 5 * 60;
 333: #endif
 334:         } else {
 335:             tmtab.b_active = SCOM;
 336: #ifdef  TM_TIMEOUT
 337:             sc->sc_timo = MIN(MAX(10 * bp->b_repcnt, 60), 5 * 60);
 338: #endif
 339:         }
 340:         if (bp->b_command == TM_SFORW || bp->b_command == TM_SREV)
 341:             tmaddr->tmbc = bp->b_repcnt;
 342:         goto dobpcmd;
 343:     }
 344:     /*
 345: 	 * The following checks handle boundary cases for operation
 346: 	 * on non-raw tapes.  On raw tapes the initialization of
 347: 	 * sc->sc_nxrec by tmphys causes them to be skipped normally
 348: 	 * (except in the case of retries).
 349: 	 */
 350:     if (dbtofsb(bp->b_blkno) > sc->sc_nxrec) {
 351:         /*
 352: 		 * Can't read past known end-of-file.
 353: 		 */
 354:         bp->b_flags |= B_ERROR;
 355:         bp->b_error = ENXIO;
 356:         goto next;
 357:     }
 358:     if (dbtofsb(bp->b_blkno) == sc->sc_nxrec && bp->b_flags & B_READ) {
 359:         /*
 360: 		 * Reading at end of file returns 0 bytes.
 361: 		 * Buffer will be cleared (if written) in writei.
 362: 		 */
 363:         bp->b_resid = bp->b_bcount;
 364:         goto next;
 365:     }
 366:     if ((bp->b_flags & B_READ) == 0)
 367:         /*
 368: 		 * Writing sets EOF.
 369: 		 */
 370:         sc->sc_nxrec = dbtofsb(bp->b_blkno) + (daddr_t) 1;
 371:     /*
 372: 	 * If the data transfer command is in the correct place,
 373: 	 * set up all registers and do the transfer.
 374: 	 */
 375:     if ((blkno = sc->sc_blkno) == dbtofsb(bp->b_blkno)) {
 376:         tmaddr->tmbc = -bp->b_bcount;
 377:         if ((bp->b_flags & B_READ) == 0) {
 378:             if (tmtab.b_errcnt)
 379:                 cmd = TM_WIRG;
 380:             else
 381:                 cmd = TM_WCOM;
 382:         } else
 383:             cmd = TM_RCOM;
 384:         tmtab.b_active = SIO;
 385:         tmaddr->tmba = bp->b_un.b_addr;
 386:         cmd = sc->sc_dens | ((bp->b_xmem & 03) << 4) | cmd;
 387: #ifdef  TM_TIMEOUT
 388:         sc->sc_timo = 60;   /* premature, but should serve */
 389: #endif
 390:         tmaddr->tmcs = cmd;
 391:         return;
 392:     }
 393:     /*
 394: 	 * Tape positioned incorrectly;
 395: 	 * set to seek forward or backward to the correct spot.
 396: 	 * This happens for raw tapes only on error retries.
 397: 	 */
 398:     tmtab.b_active = SSEEK;
 399:     if (blkno < dbtofsb(bp->b_blkno)) {
 400:         bp->b_command = TM_SFORW;
 401:         tmaddr->tmbc = (short) (blkno - dbtofsb(bp->b_blkno));
 402:     } else {
 403:         bp->b_command = TM_SREV;
 404:         tmaddr->tmbc = (short) (dbtofsb(bp->b_blkno) - blkno);
 405:     }
 406: #ifdef  TM_TIMEOUT
 407:     sc->sc_timo = MIN(MAX(10 * -tmaddr->tmbc, 60), 5 * 60);
 408: #endif
 409: 
 410: dobpcmd:
 411:     /*
 412: 	 * Do the command in bp.
 413: 	 */
 414:     tmaddr->tmcs = (sc->sc_dens | bp->b_command);
 415:     return;
 416: 
 417: next:
 418:     /*
 419: 	 * Done with this operation due to error or
 420: 	 * the fact that it doesn't do anything.
 421: 	 * Dequeue the transfer and continue processing.
 422: 	 */
 423:     tmtab.b_errcnt = 0;
 424:     tmtab.b_actf = bp->av_forw;
 425:     iodone(bp);
 426:     goto loop;
 427: }
 428: 
 429: /*
 430:  * The interrupt routine.
 431:  */
 432: tmintr()
 433: {
 434:     register struct tmdevice *tmaddr = TMADDR;
 435:     register struct buf *bp;
 436:     int teunit;
 437:     int state;
 438:     register struct te_softc *sc;
 439: 
 440:     if ((bp = tmtab.b_actf) == NULL)
 441:         return;
 442:     teunit = TEUNIT(bp->b_dev);
 443:     sc = &te_softc[teunit];
 444:     /*
 445: 	 * If last command was a rewind, and tape is still
 446: 	 * rewinding, wait for the rewind complete interrupt.
 447: 	 */
 448:     if (tmtab.b_active == SREW) {
 449:         tmtab.b_active = SCOM;
 450:         if (tmaddr->tmer & TMER_RWS) {
 451: #ifdef  TM_TIMEOUT
 452:             sc->sc_timo = 5 * 60;       /* 5 minutes */
 453: #endif
 454:             return;
 455:         }
 456:     }
 457:     /*
 458: 	 * An operation completed... record status.
 459: 	 */
 460: #ifdef  TM_TIMEOUT
 461:     sc->sc_timo = INF;
 462: #endif
 463:     sc->sc_erreg = tmaddr->tmer;
 464: #ifdef  TM_IOCTL
 465:     sc->sc_dsreg = tmaddr->tmcs;
 466:     sc->sc_resid = tmaddr->tmbc;
 467: #endif
 468:     if ((bp->b_flags & B_READ) == 0)
 469:         sc->sc_lastiow = 1;
 470:     state = tmtab.b_active;
 471:     tmtab.b_active = 0;
 472:     /*
 473: 	 * Check for errors.
 474: 	 */
 475:     if (tmaddr->tmcs & TM_ERR) {
 476:         while(tmaddr->tmer & TMER_SDWN)
 477:             ;           /* await settle down */
 478:         /*
 479: 		 * If we hit the end of the tape file, update our position.
 480: 		 */
 481:         if (tmaddr->tmer & TMER_EOF) {
 482:             tmseteof(bp);       /* set blkno and nxrec */
 483:             state = SCOM;       /* force completion */
 484:             /*
 485: 			 * Stuff bc so it will be unstuffed correctly
 486: 			 * later to get resid.
 487: 			 */
 488:             tmaddr->tmbc = -bp->b_bcount;
 489:             goto opdone;
 490:         }
 491:         /*
 492: 		 * If we were reading raw tape and the only error was that the
 493: 		 * record was too long, then we don't consider this an error.
 494: 		 */
 495:         if (bp == &rtmbuf && (bp->b_flags & B_READ) &&
 496:             (tmaddr->tmer & (TMER_HARD | TMER_SOFT)) == TMER_RLE)
 497:             goto ignoreerr;
 498:         /*
 499: 		 * If error is not hard, and this was an i/o operation
 500: 		 * retry up to 8 times.
 501: 		 */
 502:         if ((tmaddr->tmer & TMER_HARD) == 0 && state == SIO) {
 503:             if (++tmtab.b_errcnt < 7) {
 504:                 sc->sc_blkno++;
 505:                 goto opcont;
 506:             }
 507:         } else
 508:             /*
 509: 			 * Hard or non-i/o errors on non-raw tape
 510: 			 * cause it to close.
 511: 			 */
 512:             if (sc->sc_openf > 0 && bp != &rtmbuf)
 513:                 sc->sc_openf = -1;
 514:         /*
 515: 		 * Couldn't recover error
 516: 		 */
 517: #ifdef  UCB_DEVERR
 518:         printf("te%d: hard error bn%D er=%b\n",
 519:            teunit, bp->b_blkno, sc->sc_erreg, TMER_BITS);
 520: #else
 521:         deverror(bp, sc->sc_erreg, 0);
 522: #endif
 523:         bp->b_flags |= B_ERROR;
 524:         goto opdone;
 525:     }
 526:     /*
 527: 	 * Advance tape control finite state machine.
 528: 	 */
 529: ignoreerr:
 530:     switch (state) {
 531:     case SIO:
 532:         /*
 533: 		 * Read/write increments tape block number.
 534: 		 */
 535:         sc->sc_blkno++;
 536:         goto opdone;
 537:     case SCOM:
 538:         /*
 539: 		 * For forward/backward space record update current position.
 540: 		 */
 541:         if (bp == &ctmbuf)
 542:             switch (bp->b_command) {
 543:             case TM_SFORW:
 544:                 sc->sc_blkno -= (daddr_t) (bp->b_repcnt);
 545:                 break;
 546:             case TM_SREV:
 547:                 sc->sc_blkno += (daddr_t) (bp->b_repcnt);
 548:                 break;
 549:             }
 550:         goto opdone;
 551:     case SSEEK:
 552:         sc->sc_blkno = dbtofsb(bp->b_blkno);
 553:         goto opcont;
 554:     default:
 555:         panic("tmintr");
 556:     }
 557: opdone:
 558:     /*
 559: 	 * Reset error count and remove
 560: 	 * from device queue.
 561: 	 */
 562:     tmtab.b_errcnt = 0;
 563:     tmtab.b_actf = bp->av_forw;
 564:     bp->b_resid = -tmaddr->tmbc;
 565:     iodone(bp);
 566: 
 567: opcont:
 568:     tmstart();
 569: }
 570: 
 571: #ifdef  TM_TIMEOUT
 572: tmtimer(dev)
 573: register dev_t  dev;
 574: {
 575:     register s;
 576:     register struct te_softc *sc = &te_softc[TEUNIT(dev)];
 577: 
 578:     if (sc->sc_timo != INF && (sc->sc_timo -= 5) < 0) {
 579:         printf("te%d: lost interrupt\n", TEUNIT(dev));
 580:         sc->sc_timo = INF;
 581:         s = spl5();
 582:         tmintr();
 583:         splx(s);
 584:     }
 585:     timeout(tmtimer, (caddr_t) dev, 5 * hz);
 586: }
 587: #endif
 588: 
 589: tmseteof(bp)
 590: register struct buf *bp;
 591: {
 592:     register struct tmdevice *tmaddr = TMADDR;
 593:     daddr_t bn = dbtofsb(bp->b_blkno);
 594:     register struct te_softc *sc = &te_softc[TEUNIT(bp->b_dev)];
 595: 
 596:     if (bp == &ctmbuf) {
 597:         if (sc->sc_blkno > bn) {
 598:             /* reversing */
 599:             sc->sc_nxrec = bn - (daddr_t) (tmaddr->tmbc);
 600:             sc->sc_blkno = sc->sc_nxrec;
 601:         } else {
 602:             /* spacing forward */
 603:             sc->sc_blkno = bn + (daddr_t) (tmaddr->tmbc);
 604:             sc->sc_nxrec = sc->sc_blkno - (daddr_t) 1;
 605:         }
 606:         return;
 607:     }
 608:     /* eof on read */
 609:     sc->sc_nxrec = bn;
 610: }
 611: 
 612: tmread(dev)
 613: register dev_t dev;
 614: {
 615:     tmphys(dev);
 616:     bphysio(tmstrategy, &rtmbuf, dev, B_READ);
 617: }
 618: 
 619: tmwrite(dev)
 620: register dev_t dev;
 621: {
 622:     tmphys(dev);
 623:     bphysio(tmstrategy, &rtmbuf, dev, B_WRITE);
 624: }
 625: 
 626: /*
 627:  * Set up sc_blkno and sc_nxrec
 628:  * so that the tape will appear positioned correctly.
 629:  */
 630: tmphys(dev)
 631: dev_t dev;
 632: {
 633:     daddr_t a;
 634:     register struct te_softc *sc = &te_softc[TEUNIT(dev)];
 635: 
 636:     a = dbtofsb(u.u_offset >> 9);
 637:     sc->sc_blkno = a;
 638:     sc->sc_nxrec = a + 1;
 639: }
 640: 
 641: #ifdef  TM_IOCTL
 642: /*ARGSUSED*/
 643: tmioctl(dev, cmd, addr, flag)
 644: dev_t dev;
 645: caddr_t addr;
 646: {
 647:     register struct buf *bp = &ctmbuf;
 648:     register struct te_softc *sc = &te_softc[TEUNIT(dev)];
 649:     register callcount;
 650:     u_short fcount;
 651:     struct mtop mtop;
 652:     struct mtget mtget;
 653:     /* we depend on the values and order of the MT codes here */
 654:     static tmops[] = {TM_WEOF,TM_SFORW,TM_SREV,TM_SFORW,TM_SREV,TM_REW,TM_OFFL,TM_SENSE};
 655: 
 656:     switch (cmd) {
 657: 
 658:     case MTIOCTOP:  /* tape operation */
 659:         if (copyin((caddr_t)addr, (caddr_t)&mtop, sizeof(mtop))) {
 660:             u.u_error = EFAULT;
 661:             return;
 662:         }
 663:         switch(mtop.mt_op) {
 664:         case MTWEOF:
 665:             callcount = mtop.mt_count;
 666:             fcount = 1;
 667:             break;
 668:         case MTFSF:
 669:         case MTBSF:
 670:             callcount = mtop.mt_count;
 671:             fcount = INF;
 672:             break;
 673:         case MTFSR:
 674:         case MTBSR:
 675:             callcount = 1;
 676:             fcount = mtop.mt_count;
 677:             break;
 678:         case MTREW:
 679:         case MTOFFL:
 680:         case MTNOP:
 681:             callcount = 1;
 682:             fcount = 1;
 683:             break;
 684:         default:
 685:             u.u_error = ENXIO;
 686:             return;
 687:         }
 688:         if (callcount <= 0 || fcount <= 0) {
 689:             u.u_error = ENXIO;
 690:             return;
 691:         }
 692:         while (--callcount >= 0) {
 693:             tmcommand(dev, tmops[mtop.mt_op], fcount);
 694:             if ((mtop.mt_op == MTFSR || mtop.mt_op == MTBSR) &&
 695:                 bp->b_resid) {
 696:                 u.u_error = EIO;
 697:                 break;
 698:             }
 699:             if ((bp->b_flags & B_ERROR) || sc->sc_erreg & TMER_BOT)
 700:                 break;
 701:         }
 702:         geterror(bp);
 703:         return;
 704:     case MTIOCGET:
 705:         mtget.mt_erreg = sc->sc_erreg;
 706:         mtget.mt_dsreg = sc->sc_dsreg;
 707:         mtget.mt_resid = sc->sc_resid;
 708:         mtget.mt_type = MT_ISTM;
 709:         if (copyout((caddr_t)&mtget, addr, sizeof(mtget)))
 710:             u.u_error = EFAULT;
 711:         return;
 712:     default:
 713:         u.u_error = ENXIO;
 714:     }
 715: }
 716: #endif
 717: #endif	NTM

Defined functions

Defined variables

Defined struct's

Defined macros