i386/ucla/src/lab3/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 #include <kern/env.h>
  13
  14 // Test the stack backtrace function (used in lab 1 only)
  15 void
  16 test_backtrace(int x)
  17 {
  18         cprintf("entering test_backtrace %d\n", x);
  19         if (x > 0)
  20                 test_backtrace(x-1);
  21         else
  22                 mon_backtrace(0, 0, 0);
  23         cprintf("leaving test_backtrace %d\n", x);
  24 }
  25
  26 // Test kernel breakpoint functionality (used in lab 2 only)
  27 static void test_kernel_breakpoint(void) __attribute__((noinline));
  28 static void
  29 test_kernel_breakpoint(void)
  30 {
  31         __asm__ __volatile__("int3");
  32         // Then the breakpoint should return (after the user types 'exit')
  33         cprintf("Breakpoint succeeded!\n");
  34 }
  35
  36 asmlinkage void
  37 i386_init(void)
  38 {
  39         extern char edata[], end[];
  40         extern const uintptr_t sctors[], ectors[];
  41         const uintptr_t *ctorva;
  42
  43         // Initialize the console.
  44         // Can't call cprintf until after we do this!
  45         cons_init();
  46
  47         // Then call any global constructors (e.g., defined by C++).
  48         // This relies on linker script magic to define the 'sctors' and
  49         // 'ectors' symbols; see kern/kernel.ld.
  50         // Call after cons_init() so we can cprintf() if necessary.
  51         for (ctorva = ectors; ctorva > sctors; )
  52                 ((void(*)()) *--ctorva)();
  53
  54         cprintf("6828 decimal is %o octal!\n", 6828);
  55
  56         // Lab 2 memory management initialization functions
  57         mem_init();
  58
  59         // Lab 2 interrupt and gate descriptor initialization functions
  60         idt_init();
  61
  62         // Lab 3 user environment initialization functions
  63         env_init();
  64
  65         // Temporary test code specific to LAB 3
  66 #if defined(TEST)
  67         // Don't touch -- used by grading script!
  68         ENV_CREATE2(TEST, TESTSIZE);
  69 #else
  70         // Touch all you want.
  71         ENV_CREATE(user_hello);
  72 #endif // TEST*
  73
  74
  75         // We only have one user environment for now, so just run it.
  76         env_run(&envs[0]);
  77
  78         // Test IDT (lab 2 only)
  79         //test_kernel_breakpoint();
  80
  81         // Test the stack backtrace function (lab 1 only)
  82         //test_backtrace(5);
  83
  84         // Drop into the kernel monitor (lab 1-2 only; not reached later)
  85         while (1)
  86                 monitor(NULL);
  87 }
  88
  89
  90 /*
  91  * Variable panicstr contains argument to first call to panic; used as flag
  92  * to indicate that the kernel has already called panic.
  93  */
  94 static const char *panicstr;
  95
  96 /*
  97  * Panic is called on unresolvable fatal errors.
  98  * It prints "panic: mesg", and then enters the kernel monitor.
  99  */
 100 void
 101 _panic(const char *file, int line, const char *fmt, ...)
 102 {
 103         va_list ap;
 104
 105         if (panicstr)
 106                 goto dead;
 107         panicstr = fmt;
 108
 109         // Be extra sure that the machine is in as reasonable state
 110         __asm __volatile("cli; cld");
 111
 112         va_start(ap, fmt);
 113         cprintf("kernel panic at %s:%d: ", file, line);
 114         vcprintf(fmt, ap);
 115         cprintf("\n");
 116         va_end(ap);
 117
 118 dead:
 119         /* break into the kernel monitor */
 120         while (1)
 121                 monitor(NULL);
 122 }
 123
 124 /* like panic, but don't */
 125 void
 126 _warn(const char *file, int line, const char *fmt, ...)
 127 {
 128         va_list ap;
 129
 130         va_start(ap, fmt);
 131         cprintf("kernel warning at %s:%d: ", file, line);
 132         vcprintf(fmt, ap);
 133         cprintf("\n");
 134         va_end(ap);
 135 }