/*
* Initialize handlers for processor traps.
*/
void Init_Traps(void)
{
Install_Interrupt_Handler(12, &GPF_Handler); /* stack exception */
Install_Interrupt_Handler(13, &GPF_Handler); /* general protection fault */
Install_Interrupt_Handler(SYSCALL_INT, &Syscall_Handler);
}
void Initialize_RTC(void)
{
Install_Interrupt_Handler(IRQ8, RTC_Handler); // Install the handler
Disable_Interrupts();
outb(0x70, 0x8B); // Select register B and disable NMI
char prev = inb(0x71); // Read the current value of register B
outb(0x70, 0x8B);
outb(0x71, prev | 0x40);// Write the prev value, turning on bit 6 or register B
Enable_Interrupts();
kprintf("Real Time Clock Initialized\n");
}
static int Spawn_Program(char *exeFileData, struct Exe_Format *exeFormat)
{
struct Segment_Descriptor* desc;
unsigned long virtSize;
unsigned short codeSelector, dataSelector;
int i;
ulong_t maxva = 0;
/* Find maximum virtual address */
for (i = 0; i < exeFormat->numSegments; ++i) {
struct Exe_Segment *segment = &exeFormat->segmentList[i];
ulong_t topva = segment->startAddress + segment->sizeInMemory;
if (topva > maxva)
maxva = topva;
}
/* setup some memory space for the program */
virtSize = Round_Up_To_Page(maxva) + 4096; /* leave some slack for stack */
virtSpace = Malloc(virtSize);
memset((char *) virtSpace, '\0', virtSize);
/* Load segment data into memory */
for (i = 0; i < exeFormat->numSegments; ++i) {
struct Exe_Segment *segment = &exeFormat->segmentList[i];
memcpy(virtSpace + segment->startAddress,
exeFileData + segment->offsetInFile,
segment->lengthInFile);
}
/* allocate and init descriptors and selectors for code and data */
// Kernel code segment.
desc = Allocate_Segment_Descriptor();
Init_Code_Segment_Descriptor(
desc,
(unsigned long)virtSpace, // base address
(virtSize/PAGE_SIZE)+10, // num pages
0 // privilege level (0 == kernel)
);
codeSelector = Selector( 0, true, Get_Descriptor_Index( desc ) );
// Kernel data segment.
desc = Allocate_Segment_Descriptor();
Init_Data_Segment_Descriptor(
desc,
(unsigned long)virtSpace, // base address
(virtSize/PAGE_SIZE)+10, // num pages
0 // privilege level (0 == kernel)
);
dataSelector = Selector( 0, true, Get_Descriptor_Index( desc ) );
Install_Interrupt_Handler( 0x90, &Printrap_Handler );
if (lprogdebug)
{
Print("Spawn_Program(): all structures are set up\n");
Print(" virtSpace = %x\n", (unsigned int) virtSpace);
Print(" virtSize = %x\n", (unsigned int) virtSize);
Print(" codeSelector = %x\n", codeSelector);
Print(" dataSelector = %x\n", dataSelector);
Print("Now calling Trampoline()... \n");
}
Trampoline(codeSelector, dataSelector, exeFormat->entryAddr);
return 0;
}
