| 1 | /* mt.c 4.1 81/12/01 */ |
| 2 | |
| 3 | /* |
| 4 | * TM78/TU78 tape driver |
| 5 | */ |
| 6 | |
| 7 | #include "../h/mtreg.h" |
| 8 | #include "../h/param.h" |
| 9 | #include "../h/inode.h" |
| 10 | #include "../h/pte.h" |
| 11 | #include "../h/mbareg.h" |
| 12 | #include "saio.h" |
| 13 | #include "savax.h" |
| 14 | |
| 15 | short mttypes[] = |
| 16 | { MBDT_TU78, 0 }; |
| 17 | |
| 18 | #define MASKREG(reg) ((reg)&0xffff) |
| 19 | |
| 20 | mtopen(io) |
| 21 | register struct iob *io; |
| 22 | { |
| 23 | register int skip; |
| 24 | register struct mtdevice *mtaddr = (struct mtdevice *)mbadrv(io->i_unit); |
| 25 | int i; |
| 26 | |
| 27 | for (i = 0; mttypes[i]; i++) |
| 28 | if (mttypes[i] == (mtaddr->mtdt&MBDT_TYPE)) |
| 29 | goto found; |
| 30 | _stop("not a tape\n"); |
| 31 | found: |
| 32 | mbainit(UNITTOMBA(io->i_unit)); |
| 33 | mtaddr->mtid = MTID_CLR; |
| 34 | DELAY(250); |
| 35 | while ((mtaddr->mtid & MTID_RDY) == 0) |
| 36 | ; |
| 37 | mtstrategy(io, MT_REW); |
| 38 | skip = io->i_boff; |
| 39 | while (skip--) { |
| 40 | io->i_cc = -1; |
| 41 | mtstrategy(io, MT_SFORWF); |
| 42 | } |
| 43 | } |
| 44 | |
| 45 | mtclose(io) |
| 46 | register struct iob *io; |
| 47 | { |
| 48 | |
| 49 | mtstrategy(io, MT_REW); |
| 50 | } |
| 51 | |
| 52 | mtstrategy(io, func) |
| 53 | register struct iob *io; |
| 54 | int func; |
| 55 | { |
| 56 | register int errcnt, s, ic; |
| 57 | register struct mtdevice *mtaddr = |
| 58 | (struct mtdevice *)mbadrv(io->i_unit); |
| 59 | |
| 60 | errcnt = 0; |
| 61 | retry: |
| 62 | if (func == READ || func == WRITE) { |
| 63 | mtaddr->mtca = 1<<2; /* 1 record */ |
| 64 | mtaddr->mtbc = io->i_cc; |
| 65 | mtaddr->mter = 0; |
| 66 | mbastart(io, func); |
| 67 | do |
| 68 | s = mtaddr->mter & MTER_INTCODE; |
| 69 | while (s == 0); |
| 70 | ic = s; |
| 71 | DELAY(2000); |
| 72 | } else { |
| 73 | mtaddr->mtas = -1; |
| 74 | mtaddr->mtncs[0] = (-io->i_cc << 8)|func|MT_GO; |
| 75 | rwait: |
| 76 | do |
| 77 | s = mtaddr->mtas&0xffff; |
| 78 | while (s == 0); |
| 79 | mtaddr->mtas = mtaddr->mtas; /* clear attention */ |
| 80 | ic = mtaddr->mtner & MTER_INTCODE; |
| 81 | } |
| 82 | switch (ic) { |
| 83 | case MTER_TM: |
| 84 | case MTER_EOT: |
| 85 | case MTER_LEOT: |
| 86 | return (0); |
| 87 | |
| 88 | case MTER_DONE: |
| 89 | break; |
| 90 | |
| 91 | case MTER_RWDING: |
| 92 | goto rwait; |
| 93 | default: |
| 94 | printf("mt hard error: er=%b\n", |
| 95 | MASKREG(mtaddr->mter)); |
| 96 | mtaddr->mtid = MTID_CLR; |
| 97 | DELAY(250); |
| 98 | while ((mtaddr->mtid & MTID_RDY) == 0) |
| 99 | ; |
| 100 | return (-1); |
| 101 | |
| 102 | case MTER_RETRY: |
| 103 | printf("mt error: er=%b\n", |
| 104 | MASKREG(mtaddr->mter)); |
| 105 | if (errcnt == 10) { |
| 106 | printf("mt: unrecovered error\n"); |
| 107 | return (-1); |
| 108 | } |
| 109 | errcnt++; |
| 110 | goto retry; |
| 111 | } |
| 112 | if (errcnt) |
| 113 | printf("mt: recovered by retry\n"); |
| 114 | return (io->i_cc); /* NO PARTIAL RECORD READS!!! */ |
| 115 | } |