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interrupt: load GDT/IDT on the stack

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We have to use a separate Assembly function to do that, but maybe with some effort we can make that inline too
This commit is contained in:
Edgaru089 2021-10-14 15:51:50 +08:00
parent ebdc816d82
commit aa11d25fa8
4 changed files with 36 additions and 31 deletions
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21
interrupt/init.c
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@ -36,16 +36,9 @@ void interrupt_Init() {
assert(sizeof(interrupt_DescriptorTableReference) == 10 && "GDTR/IDTR size must be 10 bytes");
assert(offsetof(interrupt_DescriptorTableReference, base) == 2 && "GDTR/IDTR must be packed");
assert(KERNEL_IDTR_MAPPING % 4 == 0 && "IDTR not aligned to 4-byte");
assert(KERNEL_GDTR_MAPPING % 4 == 0 && "GDTR not aligned to 4-byte");
// allocate GDTR
io_WriteConsoleASCII("interrupt_Init() calling\n");
interrupt_GDTR = (interrupt_DescriptorTableReference *)KERNEL_GDTR_MAPPING;
interrupt_GDTR->length = 4 * GDT_SIZE_BYTES - 1;
interrupt_GDTR->base = (void *)KERNEL_GDT_MAPPING;
io_WriteConsoleASCII("GDTR Written\n");
// set the 2 dummy gdts
uint64_t *gdt = (uint64_t *)KERNEL_GDT_MAPPING;
@ -56,20 +49,13 @@ void interrupt_Init() {
gdt[4] = GDT_DATA_RING3;
io_WriteConsoleASCII("GDT Installed\n");
interrupt_LoadGDT(interrupt_GDTR); // set it!
interrupt_LoadGDT(4 * GDT_SIZE_BYTES - 1, (void *)KERNEL_GDT_MAPPING); // set it!
io_WriteConsoleASCII("GDT OK\n");
//interrupt_Testcode();
io_WriteConsoleASCII("Testcode OK\n");
// allocate IDTR
//interrupt_IDTR = kMalloc(sizeof(interrupt_DescriptorTableReference));
interrupt_IDTR = (interrupt_DescriptorTableReference *)KERNEL_IDTR_MAPPING;
interrupt_IDTR->length = KERNEL_IDT_SIZE - 1;
interrupt_IDTR->base = (void *)KERNEL_IDT_MAPPING;
io_WriteConsoleASCII("IDT Written\n");
interrupt_MapHandler(interrupt_Int0, 0);
interrupt_MapHandler(interrupt_Int1, 1);
interrupt_MapHandler(interrupt_Int2, 2);
@ -105,11 +91,10 @@ void interrupt_Init() {
interrupt_MapHandler(interrupt_Int128, 128);
io_WriteConsoleASCII("IDT Installed\n");
interrupt_LoadIDT(interrupt_IDTR); // set it!
interrupt_LoadIDT(KERNEL_IDT_SIZE - 1, (void *)KERNEL_IDT_MAPPING); // set it!
io_WriteConsoleASCII("IDT OK\n");
interrupt_Enabled = true;
asm volatile("sti");

10
interrupt/interrupt.h
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@ -53,14 +53,8 @@ SYSV_ABI void interrupt_Handler(int vec, int errcode, uint64_t rip, uint64_t rax
// defined in assembly
SYSV_ABI void interrupt_ReloadSegments();
inline void interrupt_LoadGDT(interrupt_DescriptorTableReference *gdtr) {
asm volatile("lgdt %0"
: "=m"(*gdtr));
}
inline void interrupt_LoadIDT(interrupt_DescriptorTableReference *idtr) {
asm volatile("lidt %0"
: "=m"(*idtr));
}
SYSV_ABI void interrupt_LoadGDT(uint16_t length_sub1, void *base_ptr);
SYSV_ABI void interrupt_LoadIDT(uint16_t length_sub1, void *base_ptr);
#define INTERRUPT_DISABLE \

29
interrupt/load_gdt.S
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@ -1,6 +1,8 @@
format elf64
public interrupt_ReloadSegments
public interrupt_LoadGDT
public interrupt_LoadIDT
section '.text' executable
@ -25,3 +27,30 @@ interrupt_ReloadSegments:
push rax
retfq
; sysvx64call void interrupt_LoadGDT(uint16_t length_sub1, void* base_ptr)
;
; Input: (uint16_t di, void* rsi)
; Clobbers: rax, flags
interrupt_LoadGDT:
mov rax, rsp ; save old RSP
sub rsp, 10
and rsp, 0xfffffffffffffffc ; align RSP to 4-byte
mov [rsp], di
mov [rsp+2], rsi
lgdt [rsp]
mov rsp, rax ; restore old RSP
ret
; sysvx64call void interrupt_LoadIDT(uint16_t length_sub1, void* base_ptr)
;
; Input: (uint16_t di, void* rsi)
; Clobbers: rax, flags
interrupt_LoadIDT:
mov rax, rsp ; save old RSP
sub rsp, 10
and rsp, 0xfffffffffffffffc ; align RSP to 4-byte
mov [rsp], di
mov [rsp+2], rsi
lidt [rsp]
mov rsp, rax ; restore old RSP
ret

7
memory/memory.h
View File

@ -21,12 +21,9 @@ extern "C" {
#define KERNEL_GDT_MAPPING (KERNEL_MISC_MAPPING + KERNEL_IDT_SIZE)
#define KERNEL_GDT_SIZE (16ull * 8)
#define KERNEL_IDTR_MAPPING (KERNEL_MISC_MAPPING + KERNEL_IDT_SIZE + KERNEL_GDT_SIZE)
#define KERNEL_GDTR_MAPPING (KERNEL_MISC_MAPPING + KERNEL_IDT_SIZE + KERNEL_GDT_SIZE + 12)
#define KERNEL_MISC_NEXT (KERNEL_MISC_MAPPING + KERNEL_IDT_SIZE + KERNEL_GDT_SIZE)
#define KERNEL_MISC_NEXT (KERNEL_MISC_MAPPING + KERNEL_IDT_SIZE + KERNEL_GDT_SIZE + 24)
#define KERNEL_MISC_SIZE (KERNEL_IDT_SIZE + KERNEL_GDT_SIZE + 24) // add all the misc sizes
#define KERNEL_MISC_SIZE (KERNEL_IDT_SIZE + KERNEL_GDT_SIZE) // add all the misc sizes
extern uint64_t paging_LoaderCodeAddress, paging_LoaderCodeSize; // physical address for loader code section