From 1cb4eb79605d9a283d9382d47e3e524291a1dcea Mon Sep 17 00:00:00 2001
From: Mark Pizzolato <mark@infocomm.com>
Date: Tue, 10 Apr 2012 05:43:59 -0700
Subject: [PATCH] Fixed Asynch I/O issues which may leave pending asynch I/O in
 limbo when device resets happen (found by Sergey Oboguev)

---
 PDP11/pdp11_rq.c |  1 +
 sim_defs.h       |  2 +-
 sim_disk.c       | 10 ++++++++++
 sim_disk.h       |  1 +
 sim_tape.c       |  5 +++++
 5 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/PDP11/pdp11_rq.c b/PDP11/pdp11_rq.c
index 130cea40..aa6120a1 100644
--- a/PDP11/pdp11_rq.c
+++ b/PDP11/pdp11_rq.c
@@ -2561,6 +2561,7 @@ rq_clrint (cp);                                         /* clr intr req */
 for (i = 0; i < (RQ_NUMDR + 2); i++) {                  /* init units */
     uptr = dptr->units + i;
     sim_cancel (uptr);                                  /* clr activity */
+    sim_disk_reset (uptr);
     uptr->cnum = cidx;                                  /* set ctrl index */
     uptr->flags = uptr->flags & ~(UNIT_ONL | UNIT_ATP);
     uptr->uf = 0;                                       /* clr unit flags */
diff --git a/sim_defs.h b/sim_defs.h
index 32ad7bdd..7a35044c 100644
--- a/sim_defs.h
+++ b/sim_defs.h
@@ -606,7 +606,7 @@ extern int32 sim_asynch_inst_latency;
 #elif defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_4) || defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_8)
 #define InterlockedCompareExchangePointer(Destination, Exchange, Comparand) __sync_val_compare_and_swap(Destination, Comparand, Exchange)
 #elif defined(__DECC_VER)
-#define InterlockedCompareExchangePointer(Destination, Exchange, Comparand) (void *)((int32)_InterlockedCompareExchange64_rel(Destination, Exchange, Comparand))
+#define InterlockedCompareExchangePointer(Destination, Exchange, Comparand) (void *)((int32)_InterlockedCompareExchange64(Destination, Exchange, Comparand))
 #else
 #error "Implementation of function InterlockedCompareExchangePointer() is needed to build with USE_AIO_INTRINSICS"
 #endif
diff --git a/sim_disk.c b/sim_disk.c
index 32627227..ee85441c 100644
--- a/sim_disk.c
+++ b/sim_disk.c
@@ -1073,6 +1073,16 @@ if (close_function (fileref) == EOF)
 return SCPE_OK;
 }
 
+t_stat sim_disk_reset (UNIT *uptr)
+{
+if (!(uptr->flags & UNIT_ATT))                          /* attached? */
+    return SCPE_OK;
+_sim_disk_io_flush(uptr);
+AIO_VALIDATE;
+AIO_UPDATE_QUEUE;
+return SCPE_OK;
+}
+
 /* Factory bad block table creation routine
 
    This routine writes a DEC standard 044 compliant bad block table on the
diff --git a/sim_disk.h b/sim_disk.h
index b704604e..1295ac91 100644
--- a/sim_disk.h
+++ b/sim_disk.h
@@ -78,6 +78,7 @@ t_stat sim_disk_set_capac (UNIT *uptr, int32 val, char *cptr, void *desc);
 t_stat sim_disk_show_capac (FILE *st, UNIT *uptr, int32 val, void *desc);
 t_stat sim_disk_set_asynch (UNIT *uptr, int latency);
 t_stat sim_disk_clr_asynch (UNIT *uptr);
+t_stat sim_disk_reset (UNIT *uptr);
 t_bool sim_disk_isavailable (UNIT *uptr);
 t_bool sim_disk_isavailable_a (UNIT *uptr, DISK_PCALLBACK callback);
 t_bool sim_disk_wrp (UNIT *uptr);
diff --git a/sim_tape.c b/sim_tape.c
index 8c4d7bce..c6cbe410 100644
--- a/sim_tape.c
+++ b/sim_tape.c
@@ -1715,6 +1715,11 @@ return r;
 t_stat sim_tape_reset (UNIT *uptr)
 {
 MT_CLR_PNU (uptr);
+if (!(uptr->flags & UNIT_ATT))                          /* attached? */
+    return SCPE_OK;
+_sim_tape_io_flush(uptr);
+AIO_VALIDATE;
+AIO_UPDATE_QUEUE;
 return SCPE_OK;
 }