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interrupt, smp: fix GDT code/data segment order, fix GDT size

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This commit is contained in:
Edgaru089 2021-11-14 17:31:11 +08:00
parent db6959a932
commit 54f8aa54c1
6 changed files with 27 additions and 21 deletions
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19
interrupt/init.c
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@ -5,6 +5,7 @@
#include "../runtime/stdio.h"
#include "../runtime/panic_assert.h"
#include "testcode.h"
#include "string.h"
bool interrupt_Enabled;
@ -28,7 +29,7 @@ SYSV_ABI void interrupt_MapHandler(void *handler, int interrupt) {
*/
// defined in assembly
SYSV_ABI void interrupt_MapHandler(void *handler, int interrupt);
//SYSV_ABI void interrupt_MapHandler(void *handler, int interrupt);
void interrupt_Init() {
@ -40,21 +41,21 @@ void interrupt_Init() {
io_WriteConsoleASCII("interrupt_Init() calling\n");
// set the 2 dummy gdts
uint64_t *gdt = (uint64_t *)KERNEL_GDT_MAPPING;
gdt[0] = 0;
gdt[1] = GDT_EXEC;
gdt[2] = GDT_DATA;
gdt[3] = GDT_EXEC_RING3;
gdt[4] = GDT_DATA_RING3;
uint64_t *gdt = (uint64_t *)KERNEL_GDT_MAPPING;
gdt[0] = 0;
gdt[GDT_DATA_SELECTOR >> 3] = GDT_DATA;
gdt[GDT_EXEC_SELECTOR >> 3] = GDT_EXEC;
gdt[GDT_DATA_RING3_SELECTOR >> 3] = GDT_DATA_RING3;
gdt[GDT_EXEC_RING3_SELECTOR >> 3] = GDT_EXEC_RING3;
io_WriteConsoleASCII("GDT Installed\n");
interrupt_LoadGDT(4 * GDT_SIZE_BYTES - 1, (void *)KERNEL_GDT_MAPPING); // set it!
interrupt_LoadGDT(5 * GDT_SIZE_BYTES - 1, (void *)KERNEL_GDT_MAPPING); // set it!
io_WriteConsoleASCII("GDT OK\n");
//interrupt_Testcode();
io_WriteConsoleASCII("Testcode OK\n");
memset((void *)KERNEL_IDT_MAPPING, 0, KERNEL_IDT_SIZE);
interrupt_MapHandler(interrupt_Int0, 0);
interrupt_MapHandler(interrupt_Int1, 1);
interrupt_MapHandler(interrupt_Int2, 2);

10
interrupt/interrupt.h
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@ -8,16 +8,16 @@ extern "C" {
#endif
#define GDT_SIZE_BYTES 4
#define GDT_SIZE_BYTES 8
#define GDT_EXEC 0x00AF9A000000FFFFull // Base=0, Limit=max, Access=Present|Ring0|TypeUser|Exec|Readable, Flag=GranularityPage|Long
#define GDT_DATA 0x00EF92000000FFFFull // Base=0, Limit=max, Access=Present|Ring0|TypeUser|Writable, Flag=GranularityPage|Size
#define GDT_EXEC_RING3 0x00AFFA000000FFFFull // Base=0, Limit=max, Access=Present|Ring3|TypeUser|Exec|Readable, Flag=GranularityPage|Long
#define GDT_DATA_RING3 0x00EFF2000000FFFFull // Base=0, Limit=max, Access=Present|Ring3|TypeUser|Writable, Flag=GranularityPage|Size
#define GDT_EXEC_SELECTOR 0x08 // SelectorIndex=1, TableIndicator=GDT(0), Privilege=Ring0
#define GDT_DATA_SELECTOR 0x10 // SelectorIndex=2, TableIndicator=GDT(0), Privilege=Ring0
#define GDT_EXEC_RING3_SELECTOR 0x1B // SelectorIndex=3, TableIndicator=GDT(0), Privilege=Ring3
#define GDT_DATA_RING3_SELECTOR 0x23 // SelectorIndex=4, TableIndicator=GDT(0), Privilege=Ring3
#define GDT_DATA_SELECTOR 0x08 // SelectorIndex=1, TableIndicator=GDT(0), Privilege=Ring0
#define GDT_EXEC_SELECTOR 0x10 // SelectorIndex=2, TableIndicator=GDT(0), Privilege=Ring0
#define GDT_DATA_RING3_SELECTOR 0x1B // SelectorIndex=3, TableIndicator=GDT(0), Privilege=Ring3
#define GDT_EXEC_RING3_SELECTOR 0x23 // SelectorIndex=4, TableIndicator=GDT(0), Privilege=Ring3
#define IDT_PRESENT (1ull << 47)
#define IDT_RING0 0

8
interrupt/interrupt_testcode.S
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@ -46,12 +46,18 @@ interrupt_Testcode:
lidt [idtr]
mov rax, int_handler
mov [idt+49*16], ax
mov word [idt+49*16+2], 0x08
mov word [idt+49*16+2], 0x10
mov word [idt+49*16+4], 0x8e00
shr rax, 16
mov [idt+49*16+6], ax
shr rax, 16
mov [idt+49*16+8], rax
; load the CS segment reg with 0x10
lea rax, [.realint]
push qword 0x10
push rax
retfq
.realint:
int 49
ret

7
interrupt/load_gdt.S
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@ -11,19 +11,18 @@ section '.text' executable
;
; Clobbers: rax
interrupt_ReloadSegments:
;mov eax, 0x10 ; my data segment
xor ax, ax
mov ax, 0x08 ; my data segment
mov ds, ax
mov es, ax
mov fs, ax
mov gs, ax
mov ss, ax
;jmp 0x08:.flush
;jmp 0x10:.flush
; as in https://forum.osdev.org/viewtopic.php?f=1&t=30739
; farjump does not work in long mode, you need to do a far return:
pop rax
push qword 0x08 ; my code segment
push qword 0x10 ; my code segment
push rax
retfq

2
interrupt/map_handler.S
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@ -16,7 +16,7 @@ interrupt_MapHandler:
shl rsi, 4 ; rsi *= 16
add rsi, rax ; rsi += KERNEL_IDT_MAPPING
mov [rsi], di
mov word [rsi+2], 0x08 ; GDT_EXEC_SELECTOR (index=1)
mov word [rsi+2], 0x10 ; GDT_EXEC_SELECTOR (index=2)
mov word [rsi+4], 0x8e00
shr rdi, 16
mov [rsi+6], di

2
smp/kthread.c
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@ -72,7 +72,7 @@ smp_thread_ID smp_thread_Start(void *entry, const smp_thread_Arguments *args, un
t->waitCondition = NULL;
t->state.cs = GDT_EXEC_SELECTOR;
t->state.ss = 0;
t->state.ss = GDT_DATA_SELECTOR;
t->state.rip = (uint64_t)__smp_thread_EntryPoint;
t->state.rax = (uint64_t)entry;