From ad42508424cee7dac9ff7dc81e63e33c8df9eaa9 Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Sat, 21 Sep 1991 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1991-09-21

---
 pc/devfloppy.c | 84 ++++++++++++++++++++++++++++----------------------
 pc/devhard.c   |  2 +-
 pc/vga.c       |  3 +-
 port/devsrv.c  |  2 +-
 port/devwren.c |  2 +-
 power/devhs.c  |  5 ++-
 6 files changed, 57 insertions(+), 41 deletions(-)

diff --git a/pc/devfloppy.c b/pc/devfloppy.c
index 344c3ead2c63067e058fd52b054e17f7d665d8b5..f8b443d5b954e11541b487f51b04290f890be27b 100644
--- a/pc/devfloppy.c
+++ b/pc/devfloppy.c
@@ -110,7 +110,6 @@ struct Drive
 	int	dev;
 
 	ulong	lasttouched;	/* time last touched */
-	int	motoron;	/* motor is on */
 	int	cyl;		/* current cylinder */
 	int	confused;	/* needs to be recalibrated (or worse) */
 
@@ -137,12 +136,15 @@ struct Controller
 	int	confused;
 	int	intr;		/* true if interrupt occured */
 	Rendez	r;		/* wait here for command termination */
+	int	motor;
 
 	Rendez	kr;		/* for motor watcher */
 };
 
 Controller	floppy;
 
+#define MOTORBIT(i)	(1<<((i)+4))
+
 /*
  *  predeclared
  */
@@ -201,7 +203,7 @@ floppyreset(void)
 		dp->dev = dp - floppy.d;
 		dp->t = &floppytype[0];		/* default type */
 		floppydir[NFDIR*dp->dev].length = dp->t->cap;
-		dp->motoron = 1;
+		floppy.motor |= MOTORBIT(dp->dev);
 		dp->cyl = -1;		/* because we don't know */
 		motoroff(dp);
 	}
@@ -376,36 +378,6 @@ floppywrite(Chan *c, void *a, long n)
 	return rv;
 }
 
-/*
- *  start a floppy drive's motor.  set an alarm for .75 second later to
- *  mark it as started (we get no interrupt to tell us).
- *
- *  assume the caller qlocked the drive.
- */
-static void
-motoron(Drive *dp)
-{
-	int cmd;
-
-	cmd = (1<<(dp->dev+4)) | Fintena | Fena | dp->dev;
-	outb(Fmotor, cmd);
-	tsleep(&dp->r, return0, 0, 750);
-	dp->motoron = 1;
-	dp->lasttouched = m->ticks;
-}
-
-/*
- *  stop the floppy if it hasn't been used in 5 seconds
- */
-static void
-motoroff(Drive *dp)
-{
-	int cmd;
-
-	cmd = Fintena | Fena | dp->dev;
-	outb(Fmotor, cmd);
-	dp->motoron = 0;	
-}
 static void
 floppykproc(void *a)
 {
@@ -416,7 +388,8 @@ floppykproc(void *a)
 		;
 	for(;;){
 		for(dp = floppy.d; dp < &floppy.d[conf.nfloppy]; dp++){
-			if(dp->motoron && TK2SEC(m->ticks - dp->lasttouched) > 5
+			if((floppy.motor&MOTORBIT(dp->dev))
+			&& TK2SEC(m->ticks - dp->lasttouched) > 5
 			&& canqlock(dp)){
 				if(TK2SEC(m->ticks - dp->lasttouched) > 5)
 					motoroff(dp);
@@ -429,6 +402,46 @@ floppykproc(void *a)
 	}
 }
 
+static void
+driveselect(Drive *dp)
+{
+	int cmd;
+
+	cmd = floppy.motor | Fintena | Fena | dp->dev;
+	outb(Fmotor, cmd);
+}
+
+/*
+ *  start a floppy drive's motor.  set an alarm for .75 second later to
+ *  mark it as started (we get no interrupt to tell us).
+ *
+ *  assume the caller qlocked the drive.
+ *
+ *  this also selects the drive for subsequent operations
+ */
+static void
+motoron(Drive *dp)
+{
+	int alreadyon;
+
+	alreadyon = floppy.motor & MOTORBIT(dp->dev);
+	floppy.motor |= MOTORBIT(dp->dev);
+	driveselect(dp);
+	if(!alreadyon)
+		tsleep(&dp->r, return0, 0, 750);
+	dp->lasttouched = m->ticks;
+}
+
+/*
+ *  stop the floppy if it hasn't been used in 5 seconds
+ */
+static void
+motoroff(Drive *dp)
+{
+	floppy.motor &= ~MOTORBIT(dp->dev);
+	driveselect(dp);
+}
+
 /*
  *  send a byte to the floppy
  */
@@ -633,9 +646,9 @@ floppyrevive(void)
 		outb(Fmotor, Fintena|Fena);
 		spllo();
 		for(dp = floppy.d; dp < &floppy.d[conf.nfloppy]; dp++){
-			dp->motoron = 0;
 			dp->confused = 1;
 		}
+		floppy.motor = 0;
 		sleep(&floppy.r, interrupted, 0);
 		floppy.confused = 0;
 	}
@@ -716,8 +729,7 @@ floppyxfer(Drive *dp, int cmd, void *a, long off, long n)
 	 */
 	if(floppy.confused || dp->confused)
 		floppyrevive();
-	if(!dp->motoron)
-		motoron(dp);
+	motoron(dp);
 
 	/*
 	 *  calculate new position and seek to it (dp->len may be trimmed)
diff --git a/pc/devhard.c b/pc/devhard.c
index 884ed9e4b6efdb3cf89c27cce62c02378fd2fc50..f10dff0b14507787cc2ff9cd040612612685b0a5 100644
--- a/pc/devhard.c
+++ b/pc/devhard.c
@@ -238,7 +238,7 @@ hardattach(char *spec)
 			dp->online = 0;
 	}
 
-	return devattach('h', spec);
+	return devattach('w', spec);
 }
 
 Chan*
diff --git a/pc/vga.c b/pc/vga.c
index 78df35888ddb0d59e776ada61f019b57dddf7266..088368ca937914771f593327762b06a6426cc0a0 100644
--- a/pc/vga.c
+++ b/pc/vga.c
@@ -165,7 +165,8 @@ screeninit(void)
 
 	/*
 	 *  swizzle the font longs.
-	 *  we do it here since the font is initialized with big endian longs.
+	 *  we do it here since the font is initialized with big
+	 *  endian longs.
 	 */
 	defont = &defont0;
 	l = defont->bits->base;
diff --git a/port/devsrv.c b/port/devsrv.c
index 48116f7a75c7accb42e00f0907e6596167f350db..c0c70f719abe21bdad34b643c56effb6d2e152d9 100644
--- a/port/devsrv.c
+++ b/port/devsrv.c
@@ -181,6 +181,6 @@ srvwrite(Chan *c, void *va, long n, ulong offset)
 	fd = strtoul(buf, 0, 0);
 	fdtochan(fd, -1);	/* error check only */
 	srv.chan[i] = u->p->fgrp->fd[fd];
-	incref(u->p->fgrp->fd[fd]);
+	incref(srv.chan[i]);
 	return n;
 }
diff --git a/port/devwren.c b/port/devwren.c
index 5e79ef6e5c4899a1f7d95cf20ae5a8ff277e08ef..14c02f151a3d07ff6962847736de0dab24019055 100644
--- a/port/devwren.c
+++ b/port/devwren.c
@@ -125,7 +125,7 @@ wrenattach(char *param)
 
 	drive = wrendev(param);
 	wrenpart(drive);
-	c = devattach('r', param);
+	c = devattach('w', param);
 	c->dev = drive;
 	return c;
 }
diff --git a/power/devhs.c b/power/devhs.c
index 0e890244385962e04bf33e09a3d7c0a564f7d8bb..b61e9d61fc3e4a848c9ce41f7e24d324e46145f7 100644
--- a/power/devhs.c
+++ b/power/devhs.c
@@ -45,6 +45,7 @@ struct Hsvme {
 	uchar	buf[1024];	/* bytes being collected */
 	uchar	*wptr;		/* pointer into buf */
 	int	kstarted;	/* true if kernel process started */
+	int	started;
 
 	/* statistics */
 
@@ -124,6 +125,7 @@ hsvmerestart(Hsvme *hp)
 	addr->csr = NORESET|IPL(Intlevel)|FORCEW|IENABLE|ALIVE;
 	wbflush();
 	delay(1);
+	hp->started = 1;
 }
 
 /*
@@ -164,7 +166,8 @@ hsvmeattach(char *spec)
 	if(i >= Nhsvme)
 		error(Ebadarg);
 	hp = &hsvme[i];
-	hsvmerestart(hp);
+	if(!hp->started)
+		hsvmerestart(hp);
 
 	c = devattach('h', spec);
 	c->dev = i;