lab4

Author: ComradeProgrammer

include/env.h

@@ -7,6 +7,7 @@
 #define LOG2NENV	10
 #define NENV (1<<10)
 #define USTACKTOP (UTOP - 2*BY2PG)
+#define UXSTACKTOP (UTOP+2*BY2PG)
 #define UTEXT 0x00400000
 #define ENVX(envid)	((envid) & (NENV - 1))
 

include/mmu.h

@@ -52,11 +52,15 @@ extern char _start[];
 extern char _pg_dir[]; 
 extern void enable_mmu();
 extern void  boot_mmu_setup();
-
+/* 
 #define UPAGES 0x80000000
 #define UENVS 0x81000000
 #define TIMESTACK 0x82000000
-#define KERNEL_SP (0x82000000-BY2PG)
+#define KERNEL_SP (0x82000000-BY2PG)*/
+#define UPAGES 0x50000000
+#define UENVS 0x51000000
+#define TIMESTACK 0x52000000
+#define KERNEL_SP (0x52000000-BY2PG)
 //now we need to configure the memory map(kernel)
 /*
 |	-----------------------------------0x82000000

init/main.c

@@ -10,6 +10,8 @@ extern void printel();
 extern void irq_vector_init();
 extern void enable_interrupt_controller();
 extern void user_main_pingpong();
+extern void user_main_fktest();
+extern void user_main_fktest2();
 void main() {
     //unsigned long* tmp;
     printf(">>>main.c:\tmain is start ...>>>\n");
@@ -24,8 +26,8 @@ void main() {
     page_init();
     env_init();
 
-    env_create_priority((unsigned char *)(&(user_main_pingpong)),0,1);
-    env_create_priority((unsigned char *)(&(user_main_pingpong)),0,1);
+    env_create_priority((unsigned char *)(&(user_main_fktest2)),0,1);
+    //env_create_priority((unsigned char *)(&(user_main_pingpong)),0,1);
 
     irq_vector_init();
     //enable_irq();

lib/entry.S

@@ -153,7 +153,7 @@ error_invalid_el0_32:
 el1_irq:
 el0_irq:
 	CLI
-	ldr x16,=0x82000000//TIMESTACK
+	ldr x16,=0x52000000//TIMESTACK
 	mov sp,x16
 	saveall
 	
@@ -166,7 +166,7 @@ el0_sync:
 .extern sys_call_table
 .extern invalid_syscall
 	CLI
-	ldr x16,=0x81fff000//kernel_sp
+	ldr x16,=0x51fff000//kernel_sp
 	mov sp,x16
 	saveall
 	

lib/syscall_all.c

@@ -143,10 +143,13 @@ int sys_mem_unmap(int sysno, unsigned long envid, unsigned long va)
 int sys_env_alloc(void)
 //TODO: IMPLEMENT THIS FUNCTION WILL NOT BE USED TEMPORARILY 
 {
-    /* 
+    
 	// Your code here.
 	int r;
 	struct Env *e;
+	struct Page* pp;
+	unsigned long* newpage;
+	unsigned long currentsp;
 	// try to alloc a env
 	r=env_alloc(&e,curenv->env_id);
 	if(r<0){
@@ -155,14 +158,26 @@ int sys_env_alloc(void)
 	}
 	e->env_status=ENV_NOT_RUNNABLE;
 	bcopy(KERNEL_SP-sizeof(struct Trapframe),(void*)(&(e->env_tf)),sizeof(struct Trapframe));
-	(e->env_tf).regs[2]=0;
-	e->env_pri=curenv->env_pri;	
-	//copied from gayhub:is this necessary?
-	(e->env_tf).pc=e->env_tf.cp0_epc;
+	(e->env_tf).x[0]=0;
+	e->env_pri=curenv->env_pri;
+	//copy a stack?
+	//I have to use a fake fork
+	currentsp=ROUNDDOWN(e->env_tf.sp,BY2PG);
+	for(;currentsp<USTACKTOP;currentsp+=BY2PG){
+		r=page_alloc(&pp);
+		if(r<0){
+			printf("alloc for new stack when fork error\n");
+			return r;
+		}
+		newpage=page2pa(pp);
+		bcopy(currentsp,newpage,BY2PG);
+		r=page_insert(e->env_pgdir,pp,currentsp,PTE_V);
+	}
+	
+	e->env_status=ENV_RUNNABLE;
 
-	return e->env_id;*/
-	panic("sys_env_alloc not implemented");
-	return -1;
+
+	return e->env_id;
 }
 int sys_set_env_status(int sysno, unsigned long envid, unsigned long status)
 {

user/Makefile

@@ -5,7 +5,7 @@ INCLUDES := -I./ -I../ -I../include/
 
 .PHONY: clean
 
-all: syscall_lib.o msyscall.o ipc.o userfunct.o
+all: syscall_lib.o msyscall.o ipc.o userfunct.o fork.o
 
 clean:
 	rm -rf *~ *.o

user/fork.c

@@ -0,0 +1,8 @@
+#include<helpfunct.h>
+#include<mmu.h>
+#include<os_printf.h>
+#include<env.h>
+#include<syscall_lib.h>
+int fork(){
+    return syscall_env_alloc();
+}

user/userfunct.c

@@ -1,6 +1,42 @@
 #include<syscall_lib.h>
 #include<os_printf.h>
 #include<ipc.h>
+void user_main_fktest2(){
+	int a=0;
+	int id=0;
+
+	if((id=fork())==0)
+	{
+		if ((id=fork())==0)
+		{
+			a+=3;
+			for(;;) printf("\t\tthis is child2 :a:%d\n",a);
+		}
+		a+=2;
+		for(;;) printf("\tthis is child :a:%d\n",a);
+	}
+	a++;
+	for(;;) printf("this is father: a:%d\n",a);
+}
+void user_main_fktest(){
+	
+	unsigned long  r=0;
+	r=fork();
+	printf("%x===\n",r);
+	if(r<0){
+		panic("failed");
+	}
+	if(r==0){
+		while(1){
+			printf("i am son\n");
+		}
+	}
+	else if(r>0){
+		while(1){
+			printf("i am father\n");
+		}
+	}
+}
 void user_main1(){
 	while(1){
 		syscall_putchar('1');