9os

commit 8410cbe6340a2fd39da4866ce239b95f81569bda
parent 435ac77bd3b15f28e5f7f511e77de3eecf368a77
Author: Roberto E. Vargas Caballero <roberto.vargas@midokura.com>
Date:   Thu, 17 Nov 2022 07:14:26 +0100

os9: Use a Map for kstack

We have to switch the map for the kernel stack too.

Diffstat:
M
include/bits/amd64/arch/types.h
 | 
1
+
M
include/bits/arm64/arch/types.h
 | 
1
+
M
include/os9/os9.h
 | 
2
+-
M
src/os9/hosted/arch.c
 | 
2
--
M
src/os9/proc.c
 | 
49
+++++++++++++++++++++++++++++++++++++++----------

5 files changed, 42 insertions(+), 13 deletions(-)
diff --git a/include/bits/amd64/arch/types.h b/include/bits/amd64/arch/types.h
@@ -1,6 +1,7 @@
 /* TODO: Move these bits to other place */
 
 #define STACKADDR 0x7FFFFFFFFFFFFFF0
+#define KSTACKADDR 0xFFFFFFFFFFFFFFF0
 #define MAXTID 32767
 #define NR_TASKS 16
 #define NR_WINS  32
diff --git a/include/bits/arm64/arch/types.h b/include/bits/arm64/arch/types.h
@@ -1,6 +1,7 @@
 /* TODO: Move these bits to other place */
 
 #define STACKADDR 0x7FFFFFFFFFFFFFF0
+#define KSTACKADDR 0xFFFFFFFFFFFFFFF0
 #define MAXTID 32767
 #define NR_TASKS 16
 #define NR_WINS  32
diff --git a/include/os9/os9.h b/include/os9/os9.h
@@ -210,11 +210,11 @@ struct task {
 
 	Context ctx;
 	Ptable ptable;
-	void *kstack;
 
 	Map *text;
 	Map *data;
 	Map stack;
+	Map kstack;
 	Nspace *ns;
 	Fdset *fds;
 
diff --git a/src/os9/hosted/arch.c b/src/os9/hosted/arch.c
@@ -74,8 +74,6 @@ idle(void)
 int
 ictx(Task *tp, void *fn)
 {
-	if (!newstack(tp))
-		return -1;
 	tp->ctx.stack = (void *) tp->stack.va;
 	tp->ctx.entry = fn;
 
diff --git a/src/os9/proc.c b/src/os9/proc.c
@@ -175,6 +175,25 @@ newstack(Task *tp)
 	return mp;
 }
 
+Map *
+newkstack(Task *tp)
+{
+	Map *mp = &tp->kstack;
+
+	initref(&mp->ref);
+	mp->name = "kstack";
+	mp->perm = MW |  MR;
+
+	mp->pa = -1;
+	mp->va = KSTACKADDR & (STACKADDR-1);
+	mp->siz = PAGESIZE;
+
+	if (mapseg(mp) < 0)
+		return NULL;
+
+	return mp;
+}
+
 static Task *
 newslot(void)
 {
@@ -183,10 +202,8 @@ newslot(void)
 	lock(&procm);
 	for (tp = tasktab; tp < &tasktab[NR_TASKS]; tp++) {
 		lock(&tp->m);
-		if (tp->state == TFREE) {
-			tp->state = TINIT;
+		if (tp->state == TFREE)
 			break;
-		}
 		unlock(&tp->m);
 	}
 	unlock(&procm);
@@ -226,10 +243,13 @@ newtask(void)
 
 	if ((tp = newslot()) == NULL)
 		goto err;
+	if (!newkstack(tp))
+		goto err;
 
 	last = pid;
 	tp->pid = pid;
 	tp->ppid = (proc) ? proc->pid : 0;
+	tp->state = TINIT;
 
 	unlock(&m);
 
@@ -270,12 +290,24 @@ newfds(Fdset *from)
 }
 
 static Map *
-newmap(Map *from)
+newmap(void)
 {
 	Map *mp;
 
 	if ((mp = alloc(sizeof(*mp))) == NULL)
 		return NULL;
+	return mp;
+}
+
+static Map *
+dupmap(Map *from)
+{
+	Map *mp;
+
+	mp = newmap();
+	if (!mp)
+		return NULL;
+
 	*mp = *from;
 	initref(&mp->ref);
 	mapseg(mp); /* FIXME: we have to duplicate the pages */
@@ -386,7 +418,7 @@ rfork(int flags)
 			goto err;
 	}
 	if ((flags & RFMEM) == 0) {
-		if ((data = newmap(parent->data)) == NULL)
+		if ((data = dupmap(parent->data)) == NULL)
 			goto err;
 	}
 
@@ -461,14 +493,11 @@ kproc(void *fn)
 
 	tp->flags = 0;
 
-	tp->state = TREADY;
-
-	if ((tp->kstack = allocb(1)) == NULL)
-		goto err;
-
 	if (ictx(tp, fn) < 0)
 		goto err;
 
+	tp->state = TREADY;
+
 	return tp;
 
 err: