From 9eb51cf5371a6fdfa6fcbae8fdb23ee2da672f32 Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Tue, 5 Apr 1994 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1994-04-05

---
 carrera/main.c |  2 +-
 port/devmnt.c  | 42 +++++++++++++++++++-----------------------
 port/portfns.h |  3 ++-
 port/sysfile.c | 42 +++++++++++++++++++++++++++++++++++++++++-
 port/systab.h  |  6 +++---
 power/conf.h   |  1 +
 power/dat.h    |  7 +++++++
 power/lock.c   | 34 ++++++++++++++++++++++++++++++++++
 power/mem.h    |  4 +++-
 9 files changed, 111 insertions(+), 30 deletions(-)

diff --git a/carrera/main.c b/carrera/main.c
index 9db41f092b64793de522c6d9be48128760a6b351..ef2d4c89ddbb5b6f0dfb4e93414e79a02d6f3653 100644
--- a/carrera/main.c
+++ b/carrera/main.c
@@ -503,7 +503,7 @@ rdbginit(void)
 {
 	uchar *vec;
 	ulong jba;
-return;
+return;/**/
 	/* Only interested in the PC */
 	Mipsjmpbuf.pc = 0x8001C020;
 
diff --git a/port/devmnt.c b/port/devmnt.c
index df2867fc71908a5971f6591cce1ed9a6a7fb17f5..fc1f542316005ea47357c1816039e39063af57fd 100644
--- a/port/devmnt.c
+++ b/port/devmnt.c
@@ -79,7 +79,6 @@ Chan*
 mntattach(char *muxattach)
 {
 	Mnt *m;
-	int nest;
 	Chan *c, *mc;
 	char buf[NAMELEN];
 	struct bogus{
@@ -168,23 +167,6 @@ mntattach(char *muxattach)
 	mattach(m, c, bogus.spec);
 	poperror();
 
-#ifdef STUPIDHACK
-	/* Work out how deep we are nested and reduce the blocksize
-	 * accordingly
-	 */
-	nest = 0;
-	mc = m->c;
-	while(mc) {
-		if(mc->type != devno('M', 0))
-			break;
-		nest++;
-		if(mc->mntptr == 0)
-			break;
-		mc = mc->mntptr->c;
-	}
-	m->blocksize -= nest * 32;
-#endif STUPIDHACK
-
 	/*
 	 * Detect a recursive mount for a mount point served by exportfs.
 	 * If CHDIR is clear in the returned qid the foreign server is
@@ -495,6 +477,12 @@ mntwstat(Chan *c, char *dp)
 	mntfree(r);
 }
 
+long	 
+mntread9p(Chan *c, void *buf, long n, ulong offset)
+{
+	return mntrdwr(Tread, c, buf, n, offset, 1);
+}
+
 long	 
 mntread(Chan *c, void *buf, long n, ulong offset)
 {
@@ -563,9 +551,14 @@ mntrdwr(int type, Chan *c, void *buf, long n, ulong offset, int p9msg)
 		r->request.fid = c->fid;
 		r->request.offset = offset;
 		r->request.data = uba;
-		if(p9msg)
-			r->request.count = limit(n, m->blocksize + MAXMSG - 20);
-		else
+		if(p9msg) {
+			if(n > MAXRPC-32){
+				if(type == Twrite)
+					error("write9p too long");
+				n = MAXRPC-32;
+			}
+			r->request.count = n;
+		} else
 			r->request.count = limit(n, m->blocksize);
 		mountrpc(m, r);
 		nr = r->reply.count;
@@ -641,7 +634,7 @@ mountio(Mnt *m, Mntrpc *r)
 	}
 	else {
 		if(devchar[m->c->type] == L'M'){
-			if(mntwrite9p(m->c, r->rpc, n, 0) != n)
+			if(mntrdwr(Twrite, m->c, r->rpc, n, 0, 1) != n)
 				error(Emountrpc);
 		}else{
 			if((*devtab[m->c->type].write)(m->c, r->rpc, n, 0) != n)
@@ -696,7 +689,10 @@ mntrpcread(Mnt *m, Mntrpc *r)
 		}
 		r->reply.type = 0;
 		r->reply.tag = 0;
-		n = devtab[m->c->type].read(m->c, r->rpc, MAXRPC, 0);
+		if(devchar[m->c->type] == L'M')
+			n = mntrdwr(Tread, m->c, r->rpc, MAXRPC, 0, 1);
+		else
+			n = devtab[m->c->type].read(m->c, r->rpc, MAXRPC, 0);
 		poperror();
 		if(n == 0)
 			continue;
diff --git a/port/portfns.h b/port/portfns.h
index 16d959c996ea2791c0f9dcd010dc7ae5dac44285..0adf42e6705970bed43994c40a56116a04fb2cee 100644
--- a/port/portfns.h
+++ b/port/portfns.h
@@ -135,7 +135,9 @@ void		mfreeseg(Segment*, ulong, int);
 void		mmurelease(Proc*);
 void		mmuswitch(Proc*);
 void		mntdump(void);
+long		mntread9p(Chan*, void*, long, ulong);
 void		mntrepl(char*);
+long		mntwrite9p(Chan*, void*, long, ulong);
 int		mount(Chan*, Chan*, int, char*);
 void		mountfree(Mount*);
 void		mousebuttons(int);
@@ -262,7 +264,6 @@ void*		vmemchr(void*, int, int);
 void		wakeup(Rendez*);
 Chan*		walk(Chan*, char*, int);
 void		wlock(RWlock*);
-long		mntwrite9p(Chan*, void*, long, ulong);
 void		wunlock(RWlock*);
 #define		xalloc(s)	xallocz(s, 1)
 void*		xallocz(ulong, int);
diff --git a/port/sysfile.c b/port/sysfile.c
index 3333f5f245b4c8f77b687b118cff1dc8f6d49778..f79b525b21663b4734f408e3ff40ab8d6d31dc4d 100644
--- a/port/sysfile.c
+++ b/port/sysfile.c
@@ -287,6 +287,47 @@ unionread(Chan *c, void *va, long n)
 	return 0;
 }
 
+long
+sysread9p(ulong *arg)
+{
+	int dir;
+	long n;
+	Chan *c;
+
+	validaddr(arg[1], arg[2], 1);
+	c = fdtochan(arg[0], OREAD, 1, 1);
+	if(waserror()) {
+		close(c);
+		nexterror();
+	}
+
+	n = arg[2];
+	dir = c->qid.path&CHDIR;
+
+	if(dir) {
+		n -= n%DIRLEN;
+		if(c->offset%DIRLEN || n==0)
+			error(Etoosmall);
+	}
+
+	if(dir && c->mnt)
+		n = unionread(c, (void*)arg[1], n);
+	else if(devchar[c->type] != L'M')
+		n = (*devtab[c->type].read)(c, (void*)arg[1], n, c->offset);
+	else
+		n = mntread9p(c, (void*)arg[1], n, c->offset);
+
+
+	lock(c);
+	c->offset += n;
+	unlock(c);
+
+	poperror();
+	close(c);
+
+	return n;
+}
+
 long
 sysread(ulong *arg)
 {
@@ -345,7 +386,6 @@ syswrite9p(ulong *arg)
 		n = (*devtab[c->type].write)(c, (void*)arg[1], arg[2], c->offset);
 	else
 		n = mntwrite9p(c, (void*)arg[1], arg[2], c->offset);
-
 	lock(c);
 	c->offset += n;
 	unlock(c);
diff --git a/port/systab.h b/port/systab.h
index a8c967f1ef503e50ccb8cf5722637d7d067538ae..2df1a8c90f0b944efa4f9af5df7ec37e5e66be61 100644
--- a/port/systab.h
+++ b/port/systab.h
@@ -41,7 +41,7 @@ Syscall sysrendezvous;
 Syscall sysunmount;
 Syscall syswait;
 Syscall syswrite9p;
-Syscall ;
+Syscall sysread9p;
 Syscall ;
 Syscall	sysdeath;
 
@@ -84,7 +84,7 @@ Syscall *systab[]={
 	[UNMOUNT]	sysunmount,
 	[WAIT]		syswait,
 	[WRITE9P]	syswrite9p,
-
+	[READ9P]	sysread9p,
 
 };
 
@@ -127,6 +127,6 @@ char *sysctab[]={
 	[UNMOUNT]	"Unmount",
 	[WAIT]		"Wait",
 	[WRITE9P]	"Write9p",
-
+	[READ9P]	"Read9p",
 
 };
diff --git a/power/conf.h b/power/conf.h
index 6153f757ada7064914fbbcde5bc951dcd55ed379..9d4c3f161ceef9382317dc5ec18d9a0f6a10aa09 100644
--- a/power/conf.h
+++ b/power/conf.h
@@ -15,6 +15,7 @@ Conftab conftab[] = {
 	{"arp", &conf.arp },
 	{"frag", &conf.frag },
 	{"debugger", &conf.debugger },
+	{"ialloc", &conf.ialloc },
 	{ 0, 0 },
 };
 
diff --git a/power/dat.h b/power/dat.h
index c74219763d64787e3aa6e9e1fb6c1d1200722ada..5493811a69bf6305b2096da442a5852b7cc0a7a0 100644
--- a/power/dat.h
+++ b/power/dat.h
@@ -25,6 +25,7 @@ struct Lock
 {
 	int	val;
 	ulong	pc;
+	ulong	sr;
 };
 
 struct Label
@@ -51,6 +52,7 @@ struct Conf
 	ulong	arp;		/* Arp table size */
 	ulong	frag;		/* Ip fragment assemble queue size */
 	ulong	debugger;	/* use processor 1 as a kernel debugger */
+	ulong	ialloc;		/* bytes available for interrupt time allocation */
 };
 
 /*
@@ -134,6 +136,11 @@ struct Mach
 	Schedq	hiq;
 	Schedq	loq;
 
+	Callbk*	cbin;
+	Callbk*	cbout;
+	Callbk*	cbend;
+	Callbk	calls[NCALLBACK];
+
 	int	stack[1];
 };
 
diff --git a/power/lock.c b/power/lock.c
index 67e3b596736d12118eb8551f0834388e753f687d..dc304a032c135c2f2827caa94cc6855e6bb6efcd 100644
--- a/power/lock.c
+++ b/power/lock.c
@@ -114,6 +114,29 @@ lock(Lock *lk)
 	dumpstack();
 }	
 
+void
+ilock(Lock *lk)
+{
+	int *hwsem, hash;
+	ulong x;
+
+	x = splhi();
+	hash = lhash(lk);
+	hwsem = (int*)SBSEM+hash;
+
+	for(;;) {
+		if(muxlock(hwsem, &lk->val)){
+			lk->sr = x;
+			return;
+		}
+		while(lk->val)
+			;
+	}
+	splx(x);
+	print("lock loop %lux pc %lux held by pc %lux\n", lk, getcallerpc(lk), lk->pc);
+	dumpstack();
+}	
+
 int
 canlock(Lock *lk)
 {
@@ -129,3 +152,14 @@ unlock(Lock *l)
 	l->pc = 0;
 	l->val = 0;
 }
+
+void
+iunlock(Lock *l)
+{
+	ulong sr;
+
+	sr = l->sr;
+	l->pc = 0;
+	l->val = 0;
+	splx(sr);
+}
diff --git a/power/mem.h b/power/mem.h
index c6251e4f5d7bfc87e3cec30d862f8dffa3232eb3..43bbf782c6045dbd8507cb41936f25cdb47d92a5 100644
--- a/power/mem.h
+++ b/power/mem.h
@@ -9,10 +9,12 @@
 #define	BI2BY		8			/* bits per byte */
 #define BI2WD		32			/* bits per word */
 #define	BY2WD		4			/* bytes per word */
+#define	BY2V		8			/* bytes per very long word */
 #define	BY2PG		4096			/* bytes per page */
 #define	WD2PG		(BY2PG/BY2WD)		/* words per page */
 #define	PGSHIFT		12			/* log(BY2PG) */
-#define PGROUND(s)	(((s)+(BY2PG-1))&~(BY2PG-1))
+#define ROUND(s, sz)	(((s)+(sz-1))&~(sz-1))
+#define PGROUND(s)	ROUND(s, BY2PG)
 #define ICACHESIZE	(64*1024)		/* Power series */
 
 #define	MAXMACH		4			/* max # cpus system can run */