From 045b8506669b848ada0b2c20e6c65be518aab0d9 Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Sat, 3 Mar 1990 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1990-03-03

---
 port/chan.c   |  2 ++
 port/dev.c    |  2 ++
 port/devmnt.c | 38 +++++++++++++++++++++++++-------------
 port/page.c   | 26 ++++++++++++++------------
 power/dat.h   |  5 ++++-
 power/io.h    | 14 --------------
 6 files changed, 47 insertions(+), 40 deletions(-)

diff --git a/port/chan.c b/port/chan.c
index 918d3b7c31ca2a22dbd470502432ac816fe5505b..1eacc10f0daa22f76b90e395e3ac3696864ffaf9 100644
--- a/port/chan.c
+++ b/port/chan.c
@@ -78,6 +78,8 @@ loop:
 		c->offset = 0;
 		c->mnt = 0;
 		c->stream = 0;
+		c->mchan = 0;
+		c->mqid = 0;
 		return c;
 	}
 	unlock(&chanalloc);
diff --git a/port/dev.c b/port/dev.c
index cac778c467536fa6af4bd82469fa68fa065f1858..03e8b481bdb54ac2dfc300eb20595dac6415e3d3 100644
--- a/port/dev.c
+++ b/port/dev.c
@@ -76,6 +76,8 @@ devclone(Chan *c, Chan *nc)
 	nc->dev = c->dev;
 	nc->flag = c->flag;
 	nc->mnt = c->mnt;
+	nc->mchan = c->mchan;
+	nc->mqid = c->mqid;
 	return nc;
 }
 
diff --git a/port/devmnt.c b/port/devmnt.c
index 867f76f48e9c0f20f790750d8755df44825cb019..0d7b689eeb24ede701181af7f5489e48282085bb 100644
--- a/port/devmnt.c
+++ b/port/devmnt.c
@@ -18,6 +18,7 @@ struct Mnt
 {
 	Ref;			/* for number of chans, incl. mntpt but not msg */
 	QLock;			/* for access */
+	ulong	mntid;		/* serial # */
 	Chan	*msg;		/* for reading and writing messages */
 	Chan	*mntpt;		/* channel in user's name space */
 };
@@ -50,6 +51,12 @@ struct
 	Mnthdr	*free;
 }mnthdralloc;
 
+struct
+{
+	Lock;
+	long	id;
+}mntid;
+
 Mnt	*mnt;
 void	mntxmit(Mnt*, Mnthdr*);
 
@@ -119,19 +126,17 @@ Mnt*
 mntdev(int dev, int noerr)
 {
 	Mnt *m;
+	int i;
 
-	if(dev<0 || conf.nmntdev<=dev){
-		if(noerr)
-			return 0;
-		panic("mntdev out of range");
-	}
-	m = &mnt[dev];
-	if(m->msg == 0){
-		if(noerr)
-			return 0;
-		error(0, Eshutdown);
-	}
-	return m;
+	for(m=mnt,i=0; i<conf.nmntdev; i++,m++)		/* use a hash table some day */
+		if(m->mntid == dev){
+			if(m->msg == 0)
+				break;
+			return m;
+		}
+	if(noerr)
+		return 0;
+	error(0, Eshutdown);
 }
 
 void
@@ -187,8 +192,11 @@ mntattach(char *spec)
     Found:
 	m->ref = 1;
 	unlock(m);
+	lock(&mntid);
+	m->mntid = ++mntid.id;
+	unlock(&mntid);
 	c = devattach('M', spec);
-	c->dev = m - mnt;
+	c->dev = m->mntid;
 	m->mntpt = c;
 	cm = bogus.chan;
 	m->msg = cm;
@@ -205,6 +213,8 @@ mntattach(char *spec)
 	strcpy(mh->thdr.aname, spec);
 	mntxmit(m, mh);
 	c->qid = mh->rhdr.qid;
+	c->mchan = m->msg;
+	c->mqid = c->qid;
 	mhfree(mh);
 	poperror();
 	return c;
@@ -243,6 +253,8 @@ mntclone(Chan *c, Chan *nc)
 	nc->flag = c->flag;
 	nc->offset = c->offset;
 	nc->mnt = c->mnt;
+	nc->mchan = c->mchan;
+	nc->mqid = c->qid;
 	if(new)
 		poperror();
 	mhfree(mh);
diff --git a/port/page.c b/port/page.c
index 8d6bf85a7cc6627f0a426b82b590dde7f5e23fd9..2889dcbeda970773d0016f2228fceb4cc93dd18c 100644
--- a/port/page.c
+++ b/port/page.c
@@ -77,17 +77,18 @@ audit(char *s)
 {
 	int nf, nb;
 	Page *p;
+	static int here;
 
-static int here;
-do;while(here);
-here=1;
-
+	do;while(here);
+	here=1;
 	p = palloc.head;
 	nf=nb=0;
 	while(p){
-print("%lux %lux %d\n", p->pa, p->va, p->ref);
-if(p->o) print("\t%d %lux %c\n", p->o->nproc, p->o->qid, devchar[p->o->type]);
-delay(100);
+		print("%lux %lux %d\n", p->pa, p->va, p->ref);
+		if(p->o){
+			print("\t%d %lux %c\n", p->o->nproc, p->o->qid, devchar[p->o->type]);
+			delay(100);	/* let it drain; there's a lot here */
+		}
 		nf++;
 		p = p->next;
 	}
@@ -98,7 +99,7 @@ delay(100);
 	}
 	print("%s: nf: %d nb: %d\n", s, nf, nb);
 	delay(1000);
-here=0;
+	here=0;
 }
 
 void
@@ -187,7 +188,6 @@ loop:
 		}
 #endif
 	}
-	audit("newpage");
 	print("no physical memory\n");
 	unlock(&palloc);
 	if(u == 0)
@@ -257,7 +257,7 @@ lookorig(ulong va, ulong npte, int flag, Chan *c)
 			lock(o);
 			if(o->npage && o->qid==c->qid)
 			if(o->va==va && o->npte==npte && o->flag==flag)
-			if(o->type==c->type && o->dev==c->dev){
+			if(o->mchan==c->mchan && o->mqid==c->mqid && o->type==c->type){
 				if(o->chan == 0){
 					o->chan = c;
 					incref(c);
@@ -289,13 +289,15 @@ loop:
 		o->chan = c;
 		if(c){
 			o->type = c->type;
-			o->dev = c->dev;
 			o->qid = c->qid;
+			o->mchan = c->mchan;
+			o->mqid = c->mqid;
 			incref(c);
 		}else{
 			o->type = -1;
-			o->dev = -1;
 			o->qid = -1;
+			o->mqid = -1;
+			o->mchan = 0;
 		}
 		growpte(o, npte);
 		unlock(&origalloc);
diff --git a/power/dat.h b/power/dat.h
index 5f44a9df4526d0c4fcc2d0f9a28c263e9cfcdbbb..821a2e724d9d919e6e33f8695b4c2b7a68d22e9b 100644
--- a/power/dat.h
+++ b/power/dat.h
@@ -94,6 +94,8 @@ struct Chan
 	ulong	mountid;
 	int	fid;			/* for devmnt */
 	Stream	*stream;		/* for stream channels */
+	Chan	*mchan;			/* channel to mounted server */
+	ulong	mqid;			/* qid of root of mount point */
 };
 
 struct	FPsave
@@ -226,8 +228,9 @@ struct Orig
 	PTE	*pte;
 	Chan	*chan;			/* channel deriving segment (if open) */
 	ushort	type;			/* of channel (which could be non-open) */
-	ushort	dev;
 	ulong	qid;
+	Chan	*mchan;
+	ulong	mqid;
 	ulong	minca;			/* base of region in chan */
 	ulong	maxca;			/* end of region in chan */
 };
diff --git a/power/io.h b/power/io.h
index fc6fd02aaad8ada84e798bd600d0eb6e68f6cb21..c1a9b083c1b6a81196abb57e301297ccc0a0ee0f 100644
--- a/power/io.h
+++ b/power/io.h
@@ -78,17 +78,3 @@ struct INTVEC {
 #define	MPBERR0		IO2(ulong, 0xF48000)
 #define	MPBERR1		IO2(ulong, 0xF4C000)
 #define SBEADDR		((ulong *)(UNCACHED|0x1f080000))
-
-/*
- *  hsvme datakit board
- */
-struct hsvme {
-	ushort	version;
-	ushort	pad0x02;
-	ushort	vector;
-	ushort	pad0x06;
-	ushort	csr;
-	ushort	pad0x0A;
-	ushort	data;
-};
-#define HSVME		VMEA24SUP(struct hsvme, 0xF90000)