arch: i386: include more information in IDT

Include information about the current stack frame in the IDT handler(s).

Signed-off-by: Danny Holman <dholman@gymli.xyz>

4 files changed, 129 insertions, 73 deletions

diff --git a/arch/i386/boot/idt.c b/arch/i386/boot/idt.c
index 7213fe5..d741381 100644
--- a/arch/i386/boot/idt.c
+++ b/arch/i386/boot/idt.c
@@ -10,56 +10,56 @@ struct idt_entry idt[256];
 struct idt_ptr idtr;
 
 __attribute__((noreturn))
-void exception_handler(int number) {
-        kprintf("EXCEPTION %d CAUGHT\n", number);
+void exception_handler(struct isr_frame *frame) {
+        kprintf("Error: CPU exception: %d\n", frame->vector);
         __asm__ volatile("cli;hlt");
 }
 
 extern void idt_set_gate(uint8_t num, void (*handler)(void), uint16_t cs, uint8_t flags) {
-        idt[num].isr_low = (uint16_t)(((uint32_t)handler >> 0) & 0xFFFF);
-        idt[num].isr_high = (uint16_t)(((uint32_t)handler >> 16) & 0xFFFF);
-        idt[num].reserved = 0;
-        idt[num].kernel_cs = cs;
-        idt[num].flags = flags;
+        struct idt_entry *desc = &idt[num];
+        desc->isr_low = (uint16_t)(((uint32_t)handler >> 0) & 0xFFFF);
+        desc->isr_high = (uint16_t)(((uint32_t)handler >> 16) & 0xFFFF);
+        desc->reserved = 0;
+        desc->kernel_cs = cs;
+        desc->flags = flags;
 }
 
 void idt_install(void) {
         idtr.limit = (uint16_t)sizeof(struct idt_entry) * 256 - 1;
         idtr.base = (uint32_t)&idt[0];
 
-        memset(&idt, 0, sizeof(struct idt_entry) * 256);
-        idt_set_gate(0, isr_stub_0, 0x08, 0x8e);
-        idt_set_gate(1, isr_stub_1, 0x08, 0x8e);
-        idt_set_gate(2, isr_stub_2, 0x08, 0x8e);
-        idt_set_gate(3, isr_stub_3, 0x08, 0x8e);
-        idt_set_gate(4, isr_stub_4, 0x08, 0x8e);
-        idt_set_gate(5, isr_stub_5, 0x08, 0x8e);
-        idt_set_gate(6, isr_stub_6, 0x08, 0x8e);
-        idt_set_gate(7, isr_stub_7, 0x08, 0x8e);
-        idt_set_gate(8, isr_stub_8, 0x08, 0x8e);
-        idt_set_gate(9, isr_stub_9, 0x08, 0x8e);
-        idt_set_gate(10, isr_stub_10, 0x08, 0x8e);
-        idt_set_gate(11, isr_stub_11, 0x08, 0x8e);
-        idt_set_gate(12, isr_stub_12, 0x08, 0x8e);
-        idt_set_gate(13, isr_stub_13, 0x08, 0x8e);
-        idt_set_gate(14, isr_stub_14, 0x08, 0x8e);
-        idt_set_gate(15, isr_stub_15, 0x08, 0x8e);
-        idt_set_gate(16, isr_stub_16, 0x08, 0x8e);
-        idt_set_gate(17, isr_stub_17, 0x08, 0x8e);
-        idt_set_gate(18, isr_stub_18, 0x08, 0x8e);
-        idt_set_gate(19, isr_stub_19, 0x08, 0x8e);
-        idt_set_gate(20, isr_stub_20, 0x08, 0x8e);
-        idt_set_gate(21, isr_stub_21, 0x08, 0x8e);
-        idt_set_gate(22, isr_stub_22, 0x08, 0x8e);
-        idt_set_gate(23, isr_stub_23, 0x08, 0x8e);
-        idt_set_gate(24, isr_stub_24, 0x08, 0x8e);
-        idt_set_gate(25, isr_stub_25, 0x08, 0x8e);
-        idt_set_gate(26, isr_stub_26, 0x08, 0x8e);
-        idt_set_gate(27, isr_stub_27, 0x08, 0x8e);
-        idt_set_gate(28, isr_stub_28, 0x08, 0x8e);
-        idt_set_gate(29, isr_stub_29, 0x08, 0x8e);
-        idt_set_gate(30, isr_stub_30, 0x08, 0x8e);
-        idt_set_gate(31, isr_stub_31, 0x08, 0x8e);
+        idt_set_gate(0, isr_stub_0, 0x08, IDT_EXCEPTION);
+        idt_set_gate(1, isr_stub_1, 0x08, IDT_EXCEPTION);
+        idt_set_gate(2, isr_stub_2, 0x08, IDT_EXCEPTION);
+        idt_set_gate(3, isr_stub_3, 0x08, IDT_EXCEPTION);
+        idt_set_gate(4, isr_stub_4, 0x08, IDT_EXCEPTION);
+        idt_set_gate(5, isr_stub_5, 0x08, IDT_EXCEPTION);
+        idt_set_gate(6, isr_stub_6, 0x08, IDT_EXCEPTION);
+        idt_set_gate(7, isr_stub_7, 0x08, IDT_EXCEPTION);
+        idt_set_gate(8, isr_stub_8, 0x08, IDT_EXCEPTION);
+        idt_set_gate(9, isr_stub_9, 0x08, IDT_EXCEPTION);
+        idt_set_gate(10, isr_stub_10, 0x08, IDT_EXCEPTION);
+        idt_set_gate(11, isr_stub_11, 0x08, IDT_EXCEPTION);
+        idt_set_gate(12, isr_stub_12, 0x08, IDT_EXCEPTION);
+        idt_set_gate(13, isr_stub_13, 0x08, IDT_EXCEPTION);
+        idt_set_gate(14, isr_stub_14, 0x08, IDT_EXCEPTION);
+        idt_set_gate(15, isr_stub_15, 0x08, IDT_EXCEPTION);
+        idt_set_gate(16, isr_stub_16, 0x08, IDT_EXCEPTION);
+        idt_set_gate(17, isr_stub_17, 0x08, IDT_EXCEPTION);
+        idt_set_gate(18, isr_stub_18, 0x08, IDT_EXCEPTION);
+        idt_set_gate(19, isr_stub_19, 0x08, IDT_EXCEPTION);
+        idt_set_gate(20, isr_stub_20, 0x08, IDT_EXCEPTION);
+        idt_set_gate(21, isr_stub_21, 0x08, IDT_EXCEPTION);
+        idt_set_gate(22, isr_stub_22, 0x08, IDT_EXCEPTION);
+        idt_set_gate(23, isr_stub_23, 0x08, IDT_EXCEPTION);
+        idt_set_gate(24, isr_stub_24, 0x08, IDT_EXCEPTION);
+        idt_set_gate(25, isr_stub_25, 0x08, IDT_EXCEPTION);
+        idt_set_gate(26, isr_stub_26, 0x08, IDT_EXCEPTION);
+        idt_set_gate(27, isr_stub_27, 0x08, IDT_EXCEPTION);
+        idt_set_gate(28, isr_stub_28, 0x08, IDT_EXCEPTION);
+        idt_set_gate(29, isr_stub_29, 0x08, IDT_EXCEPTION);
+        idt_set_gate(30, isr_stub_30, 0x08, IDT_EXCEPTION);
+        idt_set_gate(31, isr_stub_31, 0x08, IDT_EXCEPTION);
 
         __asm__ volatile("lidt %0" : : "memory"(idtr));
         __asm__ volatile("sti");
diff --git a/arch/i386/boot/isr.s b/arch/i386/boot/isr.s
index 43ef3be..b5f8be5 100644
--- a/arch/i386/boot/isr.s
+++ b/arch/i386/boot/isr.s
@@ -4,42 +4,74 @@
 .global isr_stub_\num
 .type isr_stub_\num, @function
 isr_stub_\num:
-        cli
-        pushl %eax
-        pushl %ecx
-        pushl %edx
-        pushl %ds
-        pushl %esp
         pushl $\num
-        call exception_handler
-        popl %esp
-        popl %ds
-        popl %edx
-        popl %ecx
-        popl %eax
-        addl $8, %esp
-        iret
+        jmp isr_frame_asm
 .endm
 .macro isr_no_err_stub num
 .global isr_stub_\num
 .type isr_stub_\num, @function
 isr_stub_\num:
-        cli
+        pushl $0
+        pushl $\num
+        jmp isr_frame_asm
+.endm
+
+isr_frame_asm:
+        pushl %ebp
+        movl %esp, %ebp
         pushl %eax
+        pushl %ebx
+        pushl %ecx
         pushl %ecx
         pushl %edx
-        pushl %ds
-        pushl %esp
-        pushl $\num
+        pushl %esi
+        pushl %edi
+
+        movl %cr0, %eax
+        pushl %eax
+        movl %cr2, %eax
+        pushl %eax
+        movl %cr3, %eax
+        pushl %eax
+        movl %cr4, %eax
+        pushl %eax
+
+        movw %ds, %ax
+        pushl %eax
+        pushl $0
+        movw $0x10, %ax
+        movw %ax, %ds
+        movw %ax, %es
+        movw %ax, %ss
+
+        lea 0xC(%esp), %edi
+        pushl %edi
         call exception_handler
-        popl %esp
-        popl %ds
+
+        popl %eax
+        popl %eax
+        movw %ax, %ds
+        movw %ax, %es
+
+        popl %eax
+        movl %eax, %cr4
+        popl %eax
+        movl %eax, %cr3
+        popl %eax
+        movl %eax, %cr2
+        popl %eax
+        movl %eax, %cr0
+
+        popl %edi
+        popl %esi
         popl %edx
         popl %ecx
+        popl %ebx
         popl %eax
-        addl $8, %esp
+
+        popl %ebp
+        add $0x10, %esp
         iret
-.endm
 
 isr_no_err_stub 0
 isr_no_err_stub 1
diff --git a/arch/i386/include/kernel/idt.h b/arch/i386/include/kernel/idt.h
index 7ccad30..699eb96 100644
--- a/arch/i386/include/kernel/idt.h
+++ b/arch/i386/include/kernel/idt.h
@@ -4,14 +4,14 @@
 #include <stdint.h>
 
 // IDT Flags
-#define SEGMENT_PRESENT 0x8
-#define SEGMENT_RING0   0x0
-#define SEGMENT_STORAGE 0x0
-#define SEGMENT_GATE    0xE
-#define SEGMENT_DPL     0x8
+#define SEGMENT_PRESENT         0x80
+#define SEGMENT_RING0           0x00
+#define SEGMENT_RING3           0x60
+#define SEGMENT_STORAGE         0x00
+#define SEGMENT_INTERRUPT       0x0E
+#define IDT_EXCEPTION           (SEGMENT_PRESENT | SEGMENT_INTERRUPT)
 
-#define SEGMENT_FLAG    SEGMENT_PRESENT | SEGMENT_RING0 | SEGMENT_STORAGE |\
-                        SEGMENT_GATE    | SEGMENT_DPL;
+#define IDT_MAX_DESCRIPTORS     256
 
 struct idt_entry {
         uint16_t        isr_low;
@@ -26,10 +26,9 @@ struct idt_ptr {
         uint32_t        base;
 } __attribute__((packed));
 
-extern struct idt_entry idt[256];
+extern struct idt_entry idt[IDT_MAX_DESCRIPTORS];
 extern struct idt_ptr idtr;
 
 extern void idt_set_gate(uint8_t num, void(*handler)(void), uint16_t cs, uint8_t flags);
-extern void exception_handler(int num);
 
-#endif
\ No newline at end of file
+#endif
diff --git a/arch/i386/include/kernel/isr.h b/arch/i386/include/kernel/isr.h
index a924cd6..61fe22f 100644
--- a/arch/i386/include/kernel/isr.h
+++ b/arch/i386/include/kernel/isr.h
@@ -1,6 +1,31 @@
 #ifndef I386_ISR_H
 #define I386_ISR_H
 
+#include <stdint.h>
+
+struct isr_frame {
+        uint32_t cr4;
+        uint32_t cr3;
+        uint32_t cr2;
+        uint32_t cr0;
+
+        uint32_t edi;
+        uint32_t esi;
+        uint32_t edx;
+        uint32_t ecx;
+        uint32_t ebx;
+        uint32_t eax;
+
+        uint32_t ebp;
+        uint32_t vector;
+        uint32_t errno;
+        uint32_t eip;
+        uint32_t cs;
+        uint32_t eflags;
+        uint32_t esp;
+        uint32_t dss;
+} __attribute__((packed));
+
 extern void isr_stub_0(void);
 extern void isr_stub_1(void);
 extern void isr_stub_2(void);
@@ -34,4 +59,4 @@ extern void isr_stub_29(void);
 extern void isr_stub_30(void);
 extern void isr_stub_31(void);
 
-#endif
\ No newline at end of file
+#endif