Merge branch 'page' of git+ssh://amsterdam.csail.mit.edu/home/am0/6.828/xv6 into page

defs.h

@@ -155,7 +155,7 @@ void            uartputc(int);
 void            pminit(void);
 void            ksegment(void);
 void            kvmalloc(void);
-void            vminit(void);
+void            vmenable(void);
 pde_t*          setupkvm(void);
 char*           uva2ka(pde_t*, char*);
 int             allocuvm(pde_t*, char*, uint);

main.c

@@ -41,7 +41,7 @@ void
 mainc(void)
 {
   cprintf("\ncpu%d: starting xv6\n\n", cpu->id);
-  kvmalloc();      // initialze the kernel page table
+  kvmalloc();      // initialize the kernel page table
   pinit();         // process table
   tvinit();        // trap vectors
   binit();         // buffer cache
@@ -67,7 +67,7 @@ mpmain(void)
     ksegment();
     lapicinit(cpunum());
   }
-  vminit();        // turn on paging
+  vmenable();        // turn on paging
   cprintf("cpu%d: starting\n", cpu->id);
   idtinit();       // load idt register
   xchg(&cpu->booted, 1);

runoff.list

@@ -21,7 +21,6 @@ spinlock.c
 proc.h
 proc.c
 swtch.S
-vm.c
 kalloc.c
 vm.c
 

user.h

@@ -21,6 +21,7 @@ int dup(int);
 int getpid();
 char* sbrk(int);
 int sleep(int);
+int uptime();
 
 // ulib.c
 int stat(char*, struct stat*);

vm.c

@@ -369,14 +369,13 @@ kvmalloc(void)
 
 // Turn on paging.
 void
-vminit(void)
+vmenable(void)
 {
   uint cr0;
 
-  lcr3(PADDR(kpgdir));
+  switchkvm(); // load kpgdir into cr3
   cr0 = rcr0();
-  cr0 |= CR0_PE|CR0_PG|CR0_AM|CR0_WP|CR0_NE|CR0_TS|CR0_EM|CR0_MP;
-  cr0 &= ~(CR0_TS|CR0_EM);
+  cr0 |= CR0_PG;
   lcr0(cr0);
 }