From f0ac91ac3943e675d8372f7422d5fd7cbda48411 Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Fri, 23 Feb 2001 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 2001-02-23

---
 pc/mmu.c       |  2 ++
 port/sysfile.c | 63 ++++++++++++++++++++++++++++++++++++++++++++++++++
 port/systab.h  |  6 +++++
 3 files changed, 71 insertions(+)

diff --git a/pc/mmu.c b/pc/mmu.c
index 198ca9cb77ff956972a91e56e3b4c911d62d37c3..81c99891a0683c158dc25a741ce11eb08a38ad22 100644
--- a/pc/mmu.c
+++ b/pc/mmu.c
@@ -36,6 +36,7 @@ taskswitch(ulong pdb, ulong stack)
 	tss->ss2 = KDSEL;
 	tss->esp2 = stack;
 	tss->cr3 = pdb;
+	coherence();
 	putcr3(pdb);
 }
 
@@ -226,6 +227,7 @@ putmmu(ulong va, ulong pa, Page*)
 
 	s = splhi();
 	pdb[PDX(MACHADDR)] = m->pdb[PDX(MACHADDR)];
+	coherence();
 	mmuflushtlb(up->mmupdb->pa);
 	splx(s);
 }
diff --git a/port/sysfile.c b/port/sysfile.c
index 04cbc59fb5b529af7bb575018389bbaf02cfc24f..b1c9c7348a4c14ceedbc11b464f3f1c4d39c5ff0 100644
--- a/port/sysfile.c
+++ b/port/sysfile.c
@@ -445,6 +445,38 @@ sysread(ulong *arg)
 	return n;
 }
 
+long
+syspread(ulong *arg)
+{
+	long n;
+	Chan *c;
+	union {
+		uvlong v;
+		ulong u[2];
+	} o;
+
+	n = arg[2];
+	validaddr(arg[1], n, 1);
+	c = fdtochan(arg[0], OREAD, 1, 1);
+	o.u[0] = arg[3];
+	o.u[1] = arg[4];
+
+	if(waserror()) {
+		cclose(c);
+		nexterror();
+	}
+
+	if(c->qid.path&CHDIR)
+		error(Eisdir);
+
+	n = devtab[c->type]->read(c, (void*)arg[1], n, o.v);
+
+	poperror();
+	cclose(c);
+
+	return n;
+}
+
 long
 syswrite9p(ulong *arg)
 {
@@ -515,6 +547,37 @@ syswrite(ulong *arg)
 	return m;
 }
 
+long
+syspwrite(ulong *arg)
+{
+	Chan *c;
+	long m, n;
+	union {
+		uvlong v;
+		ulong u[2];
+	} o;
+
+	validaddr(arg[1], arg[2], 0);
+	n = arg[2];
+	c = fdtochan(arg[0], OWRITE, 1, 1);
+	o.u[0] = arg[3];
+	o.u[1] = arg[4];
+	if(waserror()) {
+		cclose(c);
+		nexterror();
+	}
+
+	if(c->qid.path & CHDIR)
+		error(Eisdir);
+
+	m = devtab[c->type]->write(c, (void*)arg[1], n, o.v);
+
+	poperror();
+	cclose(c);
+
+	return m;
+}
+
 static void
 sseek(ulong *arg)
 {
diff --git a/port/systab.h b/port/systab.h
index ffa86f227bdffde01daf6bfd25e66cbad5959078..574a5e492c8edb18b4f47cf9efb1c2cf4d4724d8 100644
--- a/port/systab.h
+++ b/port/systab.h
@@ -43,6 +43,8 @@ Syscall syswait;
 Syscall syswrite9p;
 Syscall sysread9p;
 Syscall sysseek;
+Syscall syspread;
+Syscall syspwrite;
 Syscall	sysdeath;
 
 Syscall *systab[]={
@@ -86,6 +88,8 @@ Syscall *systab[]={
 	[WRITE9P]	syswrite9p,
 	[READ9P]	sysread9p,
 	[SEEK]		sysseek,
+	[PREAD]		syspread,
+	[PWRITE]	syspwrite,
 };
 
 char *sysctab[]={
@@ -129,6 +133,8 @@ char *sysctab[]={
 	[WRITE9P]	"Write9p",
 	[READ9P]	"Read9p",
 	[SEEK]		"Seek",
+	[PREAD]		"Pread",
+	[PWRITE]	"Pwrite",
 };
 
 int nsyscall = (sizeof systab/sizeof systab[0]);