From 37543894c5a7de17185524a6ec2e444751247988 Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Fri, 9 Jul 1999 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1999-07-09

---
 pc/devlm78.c   | 50 ++++++++++++++++++++++++--------------------------
 pc/main.c      |  1 +
 port/devproc.c | 18 +++++++++++++++++-
 port/sysfile.c | 12 +-----------
 4 files changed, 43 insertions(+), 38 deletions(-)

diff --git a/pc/devlm78.c b/pc/devlm78.c
index 7126b7a8062f27bb639dd8c1ad7813eac3c729b4..680977eb327f17914d4941681f1d37dcbf1a82c3 100644
--- a/pc/devlm78.c
+++ b/pc/devlm78.c
@@ -230,9 +230,10 @@ read_vid(void)
 enum
 {
 	IntelVendID=	0x8086,
-	PiixBridgeID=	0x122E,
-	Piix3BridgeID=	0x7000,
-	Piix4BridgeID=	0x7110,
+	PiixID=		0x122E,
+	Piix3ID=	0x7000,
+
+	Piix4PMID=	0x7113,		/* PIIX4 power management function */
 
 	PCSC=		0x78,		/* programmable chip select control register */
 	PCSC8bytes=	0x01,
@@ -247,31 +248,28 @@ readpcilm78(void)
 	p = nil;
 	while((p = pcimatch(p, IntelVendID, 0)) != nil){
 		switch(p->did){
-		case PiixBridgeID:
-		case Piix3BridgeID:
-		case Piix4BridgeID:
-			break;
-		default:
-			continue;
+		/* these bridges have pretty easy access to the lm78 */
+		case PiixID:
+		case Piix3ID:
+			pcs = pcicfgr16(p, PCSC);
+			if(pcs & 3) {
+				/* already enabled */
+				miBASE = pcs & ~3;
+				return 0;	
+			}
+
+			/* enable the chip, use default address 0x50 */
+			pcicfgw16(p, PCSC, 0x50|PCSC8bytes);
+			pcs = pcicfgr16(p, PCSC);
+			miBASE = pcs & ~3;
+			return 0;
+
+		/* this bridge uses the SMbus */
+		case Piix4PMID:
+			return -1:
 		}
-		break;
 	}
-	if(p == nil)
-		return -1;
-
-	pcs = pcicfgr16(p, PCSC);
-	if(pcs & 3) {
-		/* already enabled */
-		miBASE = pcs & ~3;
-		return 0;	
-	}
-
-	/* enable the chip, use default address 0x50 */
-	pcicfgw16(p, PCSC, 0x50|PCSC8bytes);
-	pcs = pcicfgr16(p, PCSC);
-	miBASE = pcs & ~3;
-
-	return 0;
+	return -1;
 }
 
 static void
diff --git a/pc/main.c b/pc/main.c
index feaa593b3f7d6c6349cf787c09ae1a1fe6e9dbc4..3fe4d56711bc7592b118d7db7b49a393330af9fc 100644
--- a/pc/main.c
+++ b/pc/main.c
@@ -418,6 +418,7 @@ confinit(void)
 		if(kpages > (16*MB + conf.npage*sizeof(Page))/BY2PG){
 			kpages = (16*MB + conf.npage*sizeof(Page))/BY2PG;
 			conf.nimage = 2000;
+			kpages += (conf.nproc*KSTACK)/BY2PG;
 		}
 	} else {
 		if(userpcnt < 10) {
diff --git a/port/devproc.c b/port/devproc.c
index fe3f711a55caa6501c91daf37a0225bd0d1b7260..d2513173f5519d38e692e7adcfaf1910716dbc43 100644
--- a/port/devproc.c
+++ b/port/devproc.c
@@ -162,13 +162,15 @@ procopen(Chan *c, int omode)
 	Proc *p;
 	Pgrp *pg;
 	Chan *tc;
+	int pid;
 
 	if(c->qid.path & CHDIR)
 		return devopen(c, omode, 0, 0, procgen);
 
 	p = proctab(SLOT(c->qid));
 	pg = p->pgrp;
-	if(p->pid != PID(c->qid))
+	pid = PID(c->qid);
+	if(p->pid != pid)
 		error(Eprocdied);
 
 	omode = openmode(omode);
@@ -222,6 +224,11 @@ procopen(Chan *c, int omode)
 	if(p->state != Dead)
 		c->qid.vers = p->pid;
 
+	/* make sure the process slot didn't get reallocated while we were playing */
+	coherence();
+	if(p->pid != pid)
+		error(Eprocdied);
+
 	return devopen(c, omode, 0, 0, procgen);
 }
 
@@ -235,6 +242,12 @@ procwstat(Chan *c, char *db)
 		error(Eperm);
 
 	p = proctab(SLOT(c->qid));
+	if(waserror()){
+		qunlock(&p->debug);
+		nexterror();
+	}
+	qlock(&p->debug);
+
 	if(p->pid != PID(c->qid))
 		error(Eprocdied);
 
@@ -243,6 +256,9 @@ procwstat(Chan *c, char *db)
 
 	convM2D(db, &d);
 	p->procmode = d.mode&0777;
+
+	poperror();
+	qunlock(&p->debug);
 }
 
 static int
diff --git a/port/sysfile.c b/port/sysfile.c
index 9515a2e29b184a29a5e9b70310b0493f2de0d0dc..2ae6310f5d3a7855d048e27371a858d70da869b2 100644
--- a/port/sysfile.c
+++ b/port/sysfile.c
@@ -111,23 +111,13 @@ sysfd2path(ulong *arg)
 
 	validaddr(arg[1], arg[2], 1);
 
-	/*
-	 * Undomount below may cclose the chan so bump the
-	 * reference count to guard against it going to zero
-	 * and being freed.
-	 */
 	c = fdtochan(arg[0], -1, 0, 1);
-	if(waserror()) {
-		cclose(c);
-		nexterror();
-	}
 
 	if(c->name == nil)
 		snprint((char*)arg[1], arg[2], "<null>");
 	else
 		snprint((char*)arg[1], arg[2], "%s", c->name->s);
-
-	poperror();
+	cclose(c);
 	return 0;
 }