i386/junos/ucla/src/lab2/kern/init.c

   1 /* See COPYRIGHT for copyright information. */
   2
   3 #include <inc/stdio.h>
   4 #include <inc/string.h>
   5 #include <inc/assert.h>
   6
   7 #include <kern/monitor.h>
   8 #include <kern/console.h>
   9 #include <kern/pmap.h>
  10 #include <kern/kclock.h>
  11 #include <kern/trap.h>
  12
  13 // Test the stack backtrace function (used in lab 1 only)
  14 void
  15 test_backtrace(int x)
  16 {
  17         cprintf("entering test_backtrace %d\n", x);
  18         if (x > 0)
  19                 test_backtrace(x-1);
  20         else
  21                 mon_backtrace(0, 0, 0);
  22         cprintf("leaving test_backtrace %d\n", x);
  23 }
  24
  25 // Test kernel breakpoint functionality (used in lab 2 only)
  26 static void test_kernel_breakpoint(void) __attribute__((noinline));
  27 static void
  28 test_kernel_breakpoint(void)
  29 {
  30         __asm__ __volatile__("int3");
  31         // Then the breakpoint should return (after the user types 'exit')
  32         cprintf("Breakpoint succeeded!\n");
  33 }
  34
  35 asmlinkage void
  36 i386_init(void)
  37 {
  38         extern char edata[], end[];
  39         extern const uintptr_t sctors[], ectors[];
  40         const uintptr_t *ctorva;
  41
  42         // Initialize the console.
  43         // Can't call cprintf until after we do this!
  44         cons_init();
  45
  46         // Then call any global constructors (e.g., defined by C++).
  47         // This relies on linker script magic to define the 'sctors' and
  48         // 'ectors' symbols; see kern/kernel.ld.
  49         // Call after cons_init() so we can cprintf() if necessary.
  50         for (ctorva = ectors; ctorva > sctors; )
  51                 ((void(*)()) *--ctorva)();
  52
  53         cprintf("6828 decimal is %o octal!\n", 6828);
  54
  55         // Lab 2 memory management initialization functions
  56         mem_init();
  57
  58         // Lab 2 interrupt and gate descriptor initialization functions
  59         idt_init();
  60
  61
  62
  63
  64         // Test IDT (lab 2 only)
  65         test_kernel_breakpoint();
  66
  67         // Test the stack backtrace function (lab 1 only)
  68         //test_backtrace(5);
  69
  70         // Drop into the kernel monitor.
  71         while (1)
  72                 monitor(NULL);
  73 }
  74
  75
  76 /*
  77  * Variable panicstr contains argument to first call to panic; used as flag
  78  * to indicate that the kernel has already called panic.
  79  */
  80 static const char *panicstr;
  81
  82 /*
  83  * Panic is called on unresolvable fatal errors.
  84  * It prints "panic: mesg", and then enters the kernel monitor.
  85  */
  86 void
  87 _panic(const char *file, int line, const char *fmt, ...)
  88 {
  89         va_list ap;
  90
  91         if (panicstr)
  92                 goto dead;
  93         panicstr = fmt;
  94
  95         // Be extra sure that the machine is in as reasonable state
  96         __asm __volatile("cli; cld");
  97
  98         va_start(ap, fmt);
  99         cprintf("kernel panic at %s:%d: ", file, line);
 100         vcprintf(fmt, ap);
 101         cprintf("\n");
 102         va_end(ap);
 103
 104 dead:
 105         /* break into the kernel monitor */
 106         while (1)
 107                 monitor(NULL);
 108 }
 109
 110 /* like panic, but don't */
 111 void
 112 _warn(const char *file, int line, const char *fmt, ...)
 113 {
 114         va_list ap;
 115
 116         va_start(ap, fmt);
 117         cprintf("kernel warning at %s:%d: ", file, line);
 118         vcprintf(fmt, ap);
 119         cprintf("\n");
 120         va_end(ap);
 121 }