/**
* IDT flag overview
*
* flags = x xx 0x11x 000 ?????
* | | | \ SS = Storage Segment (0 for interrupts)
* | | \ D = Size of gate: 1 = 32 bits; 0 = 16 bits
* | \ DPL = Num. higher PL from which it is accessible
* \ P = Segment Present bit
*/
void setInterruptHandler(int vector, void (*handler)(), int maxAccessibleFromPL)
{
Word flags = (Word)(maxAccessibleFromPL << 13);
flags |= 0x8E00; // P = 1, D = 1, Type = 1110 (Interrupt Gate)
idt[vector].lowOffset = lowWord((DWord)handler);
idt[vector].segmentSelector = __KERNEL_CS;
idt[vector].flags = flags;
idt[vector].highOffset = highWord((DWord)handler);
}
void setTrapHandler(int vector, void (*handler)(), int maxAccessibleFromPL)
{
Word flags = (Word)(maxAccessibleFromPL << 13);
// Changed to 0x8e00 to convert it to an 'interrupt gate' and so the system calls will be thread-safe.
flags |= 0x8e00; // P = 1, D = 1, Type = 1110 (Interrupt Gate)
//flags |= 0x8F00; // P = 1, D = 1, Type = 1111 (Trap Gate)
idt[vector].lowOffset = lowWord((DWord)handler);
idt[vector].segmentSelector = __KERNEL_CS;
idt[vector].flags = flags;
idt[vector].highOffset = highWord((DWord)handler);
}
void setInterruptHandler(int vector, void (*handler)(), int maxAccessibleFromPL)
{
/***********************************************************************/
/* THE INTERRUPTION GATE FLAGS: R1: pg. 5-11 */
/* *************************** */
/* flags = x xx 0x110 000 ????? */
/* | | | */
/* | | \ D = Size of gate: 1 = 32 bits; 0 = 16 bits */
/* | \ DPL = Num. higher PL from which it is accessible */
/* \ P = Segment Present bit */
/***********************************************************************/
Word flags = (Word)(maxAccessibleFromPL << 13);
flags |= 0x8E00; /* P = 1, D = 1, Type = 1110 (Interrupt Gate) */
idt[vector].lowOffset = lowWord((DWord)handler);
idt[vector].segmentSelector = __KERNEL_CS;
idt[vector].flags = flags;
idt[vector].highOffset = highWord((DWord)handler);
}
void setTrapHandler(int vector, void (*handler)(), int maxAccessibleFromPL)
{
/***********************************************************************/
/* THE TRAP GATE FLAGS: R1: pg. 5-11 */
/* ******************** */
/* flags = x xx 0x111 000 ????? */
/* | | | */
/* | | \ D = Size of gate: 1 = 32 bits; 0 = 16 bits */
/* | \ DPL = Num. higher PL from which it is accessible */
/* \ P = Segment Present bit */
/***********************************************************************/
Word flags = (Word)(maxAccessibleFromPL << 13);
//flags |= 0x8F00; /* P = 1, D = 1, Type = 1111 (Trap Gate) */
/* Changed to 0x8e00 to convert it to an 'interrupt gate' and so
the system calls will be thread-safe. */
flags |= 0x8E00; /* P = 1, D = 1, Type = 1110 (Interrupt Gate) */
idt[vector].lowOffset = lowWord((DWord)handler);
idt[vector].segmentSelector = __KERNEL_CS;
idt[vector].flags = flags;
idt[vector].highOffset = highWord((DWord)handler);
}
init_frames();
init_dir_pages();
for (i = 0; i < NR_TASKS; ++i){
vdir[i] = 0;
}
allocate_DIR(&task[0].task);
set_cr3(get_DIR(&task[0].task));
set_pe_flag();
}
/***********************************************/
/************** SEGMENTATION MANAGEMENT ********/
/***********************************************/
void setGdt()
{
/* Configure TSS base address, that wasn't initialized */
gdt[KERNEL_TSS>>3].lowBase = lowWord((DWord)&(tss));
gdt[KERNEL_TSS>>3].midBase = midByte((DWord)&(tss));
gdt[KERNEL_TSS>>3].highBase = highByte((DWord)&(tss));
gdtR.base = (DWord)gdt;
gdtR.limit = 256 * sizeof(Descriptor);
set_gdt_reg(&gdtR);
}
/***********************************************/
/************* TSS MANAGEMENT*******************/
/***********************************************/
void setTSS()
{
tss.PreviousTaskLink = NULL;
