From 38a8227aa8ff14c5c1827652482f8b42293d29bf Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Thu, 31 Mar 1994 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1994-03-31

---
 carrera/dat.h  |  9 ---------
 carrera/fns.h  |  1 +
 pc/dat.h       | 10 ++++------
 pc/devlpt.c    | 19 ++++++++++++-------
 pc/main.c      |  5 +++++
 port/devproc.c |  2 +-
 port/portdat.h |  8 ++++++++
 port/qio.c     |  3 +--
 port/qlock.c   |  5 -----
 9 files changed, 32 insertions(+), 30 deletions(-)

diff --git a/carrera/dat.h b/carrera/dat.h
index 1304bde3b446aa0164a3b85728db04b0de63a325..56b66c70bc65dd348bc923c76754aff755cbaf71 100644
--- a/carrera/dat.h
+++ b/carrera/dat.h
@@ -85,15 +85,6 @@ struct Notsave
 
 #include "../port/portdat.h"
 
-#define NCALLBACK	32
-
-typedef struct Callbk Callbk;
-struct Callbk
-{
-	void	(*func)(void*);
-	void*	arg;
-};
-
 /* First FOUR members offsets known by l.s */
 struct Mach
 {
diff --git a/carrera/fns.h b/carrera/fns.h
index ffc0af91a9d53fcc6baf9632a7f90dac7c7a2362..14f48a62d9e9c45da0e7551880c28bb11d1d4cae 100644
--- a/carrera/fns.h
+++ b/carrera/fns.h
@@ -133,6 +133,7 @@ void	audiodmaintr(void);
 ulong	fwblock(void*, void*, ulong);
 ulong	frblock(void*, void*, ulong);
 void	ifree(void*);
+void	ifflush(void*);
 Block*	iallocb(int);
 void*	ifroute(ulong);
 ulong	ifunroute(ulong);
diff --git a/pc/dat.h b/pc/dat.h
index 913c52b9469cc100096e9eb39c44a0e6617db45f..7df3c7cff25b9705c944f6db5d23391ed2eca48e 100644
--- a/pc/dat.h
+++ b/pc/dat.h
@@ -114,8 +114,6 @@ struct Notsave
  *  machine dependent definitions not used by ../port/dat.h
  */
 
-#define NCALLBACK	32
-
 struct Mach
 {
 	int	machno;			/* physical id of processor */
@@ -129,10 +127,10 @@ struct Mach
 	Schedq	hiq;
 	Schedq	loq;
 
-	void	(**cbin)(void);
-	void	(**cbout)(void);
-	void	(**cbend)(void);
-	void	(*calls[NCALLBACK])(void);
+	Callbk*	cbin;
+	Callbk*	cbout;
+	Callbk*	cbend;
+	Callbk	calls[NCALLBACK];
 
 	int	tlbfault;
 	int	tlbpurge;
diff --git a/pc/devlpt.c b/pc/devlpt.c
index e2c2a87537e757d68ae53a4551d46319060f90a6..49747d6434afccea433c6566407574d706c53f2f 100644
--- a/pc/devlpt.c
+++ b/pc/devlpt.c
@@ -197,13 +197,18 @@ lptwrite(Chan *c, void *a, long n)
 static void
 outch(int base, int c)
 {
-	int status = inb(base+Qpsr);
-
-	if(!(status & Fselect) || !(status & Fnoerror))
-		error(Eio);
-	if(!(status & Fnotbusy)){
-		outb(base+Qpcr, Finitbar|Fie);
-		sleep(&lptrendez, lptready, (void *)base);
+	int status, tries;
+
+	for(tries = 0;; tries++){
+		status = inb(base+Qpsr);
+		if(!(status & Fselect) || !(status & Fnoerror))
+			error(Eio);
+		if(status & Fnotbusy)
+			break;
+		if(tries > 1000){
+			outb(base+Qpcr, Finitbar|Fie);
+			tsleep(&lptrendez, lptready, (void *)base, MS2HZ);
+		}
 	}
 	outb(base+Qdlr, c);
 	outb(base+Qpcr, Finitbar|Fstrobe);
diff --git a/pc/main.c b/pc/main.c
index 3d39191a2802946b0c79de1b6a8bd742ab910e0b..5ae9a3efa09731e7a949901349f2b222a71b020a 100644
--- a/pc/main.c
+++ b/pc/main.c
@@ -91,6 +91,11 @@ machinit(void)
 	memset(m, 0, sizeof(Mach));
 	m->machno = n;
 	m->mmask = 1<<m->machno;
+
+	/* Setup call back ring buffer */
+	m->cbin = m->calls;
+	m->cbout = m->calls;
+	m->cbend = &m->calls[NCALLBACK];
 }
 
 void
diff --git a/port/devproc.c b/port/devproc.c
index 83ef81da72bf33102618c891ebcc49de85c6c5b4..17af5921c1b95864c574894a2fa66dc52c285d7d 100644
--- a/port/devproc.c
+++ b/port/devproc.c
@@ -34,7 +34,7 @@ Dirtab procdir[] =
 	"counters",	{Qcounters},	0,			0444,
 	"ctl",		{Qctl},		0,			0000,
 	"fpregs",	{Qfpregs},	sizeof(FPsave),		0000,
-	"kregs",	{Qkregs},	sizeof(Ureg),		0400,
+	"kregs",	{Qkregs},	sizeof(Ureg),		0000,
 	"mem",		{Qmem},		0,			0000,
 	"note",		{Qnote},	0,			0000,
 	"noteid",	{Qnoteid},	0,			0666,
diff --git a/port/portdat.h b/port/portdat.h
index 289d4c6ed7b51bf6d28af778d38bbd42db8858bb..c80919d9bf99dd2204347df4eb749471fbbe83e3 100644
--- a/port/portdat.h
+++ b/port/portdat.h
@@ -595,6 +595,14 @@ struct Schedq
 	int	n;
 };
 
+#define NCALLBACK	32
+
+typedef struct Callbk Callbk;
+struct Callbk
+{
+	void	(*func)(void*);
+	void*	arg;
+};
 
 enum
 {
diff --git a/port/qio.c b/port/qio.c
index 1b7a24a22533f254fdc32ad3234c0bde5d49dd63..d06a18c7d0c95a5250a51b10b2d4a23ad894614e 100644
--- a/port/qio.c
+++ b/port/qio.c
@@ -415,8 +415,7 @@ qread(Queue *q, void *vp, int len)
 			q->synclen = len;
 			q->syncbuf = vp;
 			iunlock(q);
-			while(q->syncbuf != 0)
-				sleep(&q->rr, filled, q);
+			sleep(&q->rr, filled, q);
 			len = q->synclen;
 			poperror();
 			qunlock(&q->rlock);
diff --git a/port/qlock.c b/port/qlock.c
index 16e83a8e04fdfafec9b2c9efdeebf143655e5892..7b7fbab557decc94227e4225425f5b2d6e409af0 100644
--- a/port/qlock.c
+++ b/port/qlock.c
@@ -10,8 +10,6 @@ qlock(QLock *q)
 {
 	Proc *p, *mp;
 
-up->qpc =  getcallerpc(0);
-
 	lock(&q->use);
 	if(!q->locked) {
 		q->locked = 1;
@@ -34,7 +32,6 @@ up->qpc =  getcallerpc(0);
 int
 canqlock(QLock *q)
 {
-up->qpc =  getcallerpc(0);
 	if(!canlock(&q->use))
 		return 0;
 	if(q->locked){
@@ -51,8 +48,6 @@ qunlock(QLock *q)
 {
 	Proc *p;
 
-if(up==0) { iprint("QUNLOCK at ilevel PC=%lux\n", getcallerpc(0)); for(;;); }
-
 	lock(&q->use);
 	p = q->head;
 	if(p) {