BSD 4_1_snap development

Work on file sys/stand/omt.c

Synthesized-from: CSRG/cd1/4.1.snap

diff --git a/sys/stand/omt.c b/sys/stand/omt.c
new file mode 100644 (file)
index 0000000..9ed04cc
--- /dev/null
+++ b/sys/stand/omt.c
@@ -0,0 +1,112 @@
+/*     mt.c    4.1     81/12/01        */
+
+/*
+ * TM78/TU78 tape driver
+ */
+
+#include "../h/mtreg.h"
+#include "../h/param.h"
+#include "../h/inode.h"
+#include "../h/pte.h"
+#include "../h/mbareg.h"
+#include "saio.h"
+#include "savax.h"
+
+short  mttypes[] =
+       { MBDT_TU78, 0 };
+
+#define        MASKREG(reg)    ((reg)&0xffff)
+
+mtopen(io)
+       register struct iob *io;
+{
+       register int skip;
+       register struct mtdevice *mtaddr = (struct mtdevice *)mbadrv(io->i_unit);
+       int i;
+
+       for (i = 0; mttypes[i]; i++)
+               if (mttypes[i] == (mtaddr->mtdt&MBDT_TYPE))
+                       goto found;
+       _stop("not a tape\n");
+found:
+       mbainit(UNITTOMBA(io->i_unit));
+       mtaddr->mtid = MTID_CLR;
+       DELAY(250);
+       while ((mtaddr->mtid & MTID_RDY) == 0)
+               ;
+       mtstrategy(io, MT_REW);
+       skip = io->i_boff;
+       while (skip--) {
+               io->i_cc = -1;
+               mtstrategy(io, MT_SFORWF);
+       }
+}
+
+mtclose(io)
+       register struct iob *io;
+{
+
+       mtstrategy(io, MT_REW);
+}
+
+mtstrategy(io, func)
+       register struct iob *io;
+       int func;
+{
+       register int errcnt, s, ic;
+       register struct mtdevice *mtaddr =
+           (struct mtdevice *)mbadrv(io->i_unit);
+
+       errcnt = 0;
+retry:
+       if (func == READ || func == WRITE) {
+               mtaddr->mtca = 1<<2;    /* 1 record */
+               mtaddr->mtbc = io->i_cc;
+               mtaddr->mter = 0;
+               mbastart(io, func);
+               mbawait(io);
+               ic = mtaddr->mter & MTER_INTCODE;
+       } else {
+               mtaddr->mtas = -1;
+               mtaddr->mtncs[0] = (-io->i_cc << 8)|func|MT_GO;
+       rwait:
+               do
+                       s = mtaddr->mtas&0xffff;
+               while (s == 0);
+               mtaddr->mtas = mtaddr->mtas;    /* clear attention */
+               ic = mtaddr->mtner & MTER_INTCODE;
+       }
+       switch (ic) {
+       case MTER_TM:
+       case MTER_EOT:
+       case MTER_LEOT:
+               return (0);
+
+       case MTER_DONE:
+               break;
+
+       case MTER_RWDING:
+               goto rwait;
+       default:
+               printf("mt hard error: er=%b\n",
+                   MASKREG(mtaddr->mter));
+               mtaddr->mtid = MTID_CLR;
+               DELAY(250);
+               while ((mtaddr->mtid & MTID_RDY) == 0)
+                       ;
+               return (-1);
+
+       case MTER_RETRY:
+               printf("mt error: er=%b\n",
+                   MASKREG(mtaddr->mter));
+               if (errcnt == 10) {
+                       printf("mt: unrecovered error\n");
+                       return (-1);
+               }
+               errcnt++;
+               goto retry;
+       }
+       if (errcnt)
+               printf("mt: recovered by retry\n");
+       return (io->i_cc);      /* NO PARTIAL RECORD READS!!! */
+}