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/*
* Copyright (c) 2025 Ian Marco Moffett and the Osmora Team.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of Hyra nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <md/kfence.h>
#define KERNEL_CS 0x08
#define INT_GATE 0x8E
#define TRAP_GATE 0x8F
.macro set_trap vector, isr
movq \vector, %rdi
movq $TRAP_GATE, %rsi
leaq \isr(%rip), %rdx
xorq %rcx, %rcx
callq idt_set_gate
.endm
.macro push_frame vector
.if \vector == 10 || \vector == 11 || \vector == 12 || \vector == 13 || \vector == 14
subq $8, %rsp
.endif
pushq %rax
pushq %rcx
pushq %rdx
pushq %rbx
pushq %rsi
pushq %rdi
pushq %rbp
pushq %r8
pushq %r9
pushq %r10
pushq %r11
pushq %r12
pushq %r13
pushq %r14
pushq %r15
pushq $\vector
.endm
.macro pop_frame vector
add $8, %rsp
popq %r15
popq %r14
popq %r13
popq %r12
popq %r11
popq %r10
popq %r9
popq %r8
popq %rbp
popq %rdi
popq %rsi
popq %rbx
popq %rdx
popq %rcx
popq %rax
.if \vector == 10 || \vector == 11 || \vector == 12 || \vector == 13 || \vector == 14
add $8, %rsp
.endif
.endm
.text
.globl idt_set_gate
idt_set_gate:
/*
* Set an interrupt gate descriptor in the IDT
*
* [RDI] {0}: (uint8_t)vector
* [RSI] {1}: (uint8_t)type
* [RDX] {2}: (uintptr_t)isr
* [RCX] {3}: (uint8_t)ist
*/
pushq %rbx
pushq %rbp
pushq %r12
pushq %r13
pushq %r14
pushq %r15
shlq $4, %rdi /* Scale vector by 16 */
leaq IDT(%rip), %rbx /* Load the IDT base */
addq %rdi, %rbx /* Descriptor base -> RBX */
movw %dx, 0(%rbx) /* Offset low */
movw $KERNEL_CS, 2(%rbx) /* Segment selector */
andq $0x38, %rcx /* Zero IST[7:3] */
movb %cl, 4(%rbx) /* IST */
movb $0b10000000, 5(%rbx) /* P, DPL[0], ZERO */
andq $0xF, %rsi /* Zero TYPE[7:5] */
orb %sil, 5(%rbx) /* Type */
shrq $16, %rdx /* RDX >>= 16 */
movw %dx, 6(%rbx) /* Offset middle */
shrq $16, %rdx /* RDX >>= 16 */
movl %edx, 8(%rbx) /* Offset high */
popq %r15
popq %r14
popq %r13
popq %r12
popq %rbp
popq %rbx
retq
.globl idt_load
idt_load:
call set_traps
lea IDTR(%rip), %rdx
lidt (%rdx)
retq
set_traps:
set_trap $0x00, diverr
set_trap $0x01, debug_except
set_trap $0x02, nmi
set_trap $0x03, breakpoint
set_trap $0x04, overflow
set_trap $0x05, bound_range
set_trap $0x06, invalid_tss
set_trap $0x07, no_coproc
set_trap $0x08, double_fault
set_trap $0x0A, invalid_tss
set_trap $0x0B, seg_np
set_trap $0x0C, ss_fault
set_trap $0x0D, gpf
set_trap $0x0E, page_fault
retq
diverr:
KFENCE
push_frame 0x0
mov %rsp, %rdi
call trap_dispatch
pop_frame 0x0
KFENCE
1: cli
hlt
jmp 1b
debug_except:
KFENCE
push_frame 0x1
mov %rsp, %rdi
call trap_dispatch
pop_frame 0x1
KFENCE
1: cli
hlt
jmp 1b
nmi:
KFENCE
push_frame 0x2
mov %rsp, %rdi
call trap_dispatch
pop_frame 0x2
KFENCE
1: cli
hlt
jmp 1b
breakpoint:
KFENCE
push_frame 0x3
mov %rsp, %rdi
call trap_dispatch
pop_frame 0x3
KFENCE
1: cli
hlt
jmp 1b
overflow:
KFENCE
push_frame 0x4
mov %rsp, %rdi
call trap_dispatch
pop_frame 0x4
KFENCE
1: cli
hlt
jmp 1b
bound_range:
KFENCE
push_frame 0x5
mov %rsp, %rdi
call trap_dispatch
pop_frame 0x5
KFENCE
1: cli
hlt
jmp 1b
invl_opc:
KFENCE
push_frame 0x6
mov %rsp, %rdi
call trap_dispatch
pop_frame 0x6
KFENCE
1: cli
hlt
jmp 1b
no_coproc:
KFENCE
push_frame 0x7
mov %rsp, %rdi
call trap_dispatch
pop_frame 0x7
KFENCE
1: cli
hlt
jmp 1b
double_fault:
KFENCE_EC
push_frame 0x8
mov %rsp, %rdi
call trap_dispatch
pop_frame 0x8
KFENCE_EC
1: cli
hlt
jmp 1b
invalid_tss:
KFENCE_EC
push_frame 0xA
mov %rsp, %rdi
call trap_dispatch
pop_frame 0xA
KFENCE_EC
1: cli
hlt
jmp 1b
seg_np:
KFENCE_EC
push_frame 0xB
mov %rsp, %rdi
call trap_dispatch
pop_frame 0xB
KFENCE_EC
1: cli
hlt
jmp 1b
ss_fault:
KFENCE_EC
push_frame 0xC
mov %rsp, %rdi
call trap_dispatch
pop_frame 0xC
KFENCE_EC
1: cli
hlt
jmp 1b
gpf:
KFENCE_EC
push_frame 0xD
mov %rsp, %rdi
call trap_dispatch
pop_frame 0xD
KFENCE_EC
1: cli
hlt
jmp 1b
page_fault:
KFENCE_EC
push_frame 0xE
mov %rsp, %rdi
call trap_dispatch
pop_frame 0xE
KFENCE_EC
1: cli
hlt
jmp 1b
hlt
.section .data
.align 8
IDT:
.fill 256, 8, 512
IDTR:
limit:
.word 0xFFF
.quad IDT
/* vim: ft=gas :
*/
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