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feat: Symmetric Multiprocessing, text editor improvements, merge doom libc, implement math functions

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This commit is contained in:
Daniel Hammer
2026-03-23 20:09:11 +01:00
parent a805b06406
commit 63d9270613
46 changed files with 3004 additions and 2404 deletions
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kernel/src/Hal/SyscallEntry.asm
+20 -19
View File
@@ -1,28 +1,34 @@
;
; SyscallEntry.asm
; SYSCALL/SYSRET entry point and user-mode transition
; Copyright (c) 2025 Daniel Hammer
; SYSCALL/SYSRET entry point and user-mode transition (SMP-aware)
; Copyright (c) 2025-2026 Daniel Hammer
;
[bits 64]
section .text
extern SyscallDispatch
extern g_kernelRsp
; ============================================================
; SyscallEntry — called by the SYSCALL instruction
; ====================================================================
; Per-CPU data offsets (must match CpuData in SmpBoot.hpp)
; ====================================================================
%define CPUDATA_KERNEL_RSP 8
%define CPUDATA_USER_RSP 16
; ====================================================================
; SyscallEntry -- called by the SYSCALL instruction
; RCX = user RIP, R11 = user RFLAGS, RAX = syscall number
; Args: RDI, RSI, RDX, R10, R8, R9
; Interrupts are masked (FMASK clears IF)
; ============================================================
; ====================================================================
global SyscallEntry
SyscallEntry:
mov [rel g_userRsp], rsp ; stash user RSP
mov rsp, [rel g_kernelRsp] ; switch to kernel stack
swapgs ; GS now points to per-CPU CpuData
mov [gs:CPUDATA_USER_RSP], rsp ; save user RSP to per-CPU scratch
mov rsp, [gs:CPUDATA_KERNEL_RSP] ; switch to per-CPU kernel stack
; Build SyscallFrame on kernel stack (push order matches struct)
push qword [rel g_userRsp] ; user_rsp
push qword [gs:CPUDATA_USER_RSP] ; user_rsp
push rcx ; user_rip
push r11 ; user_rflags
push rax ; syscall_nr
@@ -61,13 +67,14 @@ SyscallEntry:
pop rcx ; user RIP
pop rsp ; user RSP
swapgs ; restore user GS
o64 sysret
; ============================================================
; JumpToUserMode — initial transition to ring 3 via IRETQ
; ====================================================================
; JumpToUserMode -- initial transition to ring 3 via IRETQ
; RDI = user RIP (entry point)
; RSI = user RSP (top of user stack)
; ============================================================
; ====================================================================
global JumpToUserMode
JumpToUserMode:
mov ax, 0x1B ; UserData | RPL3
@@ -79,11 +86,5 @@ JumpToUserMode:
push 0x202 ; RFLAGS (IF=1)
push 0x23 ; CS = UserCode | RPL3
push rdi ; RIP = entry point
swapgs ; switch from kernel GS to user GS
iretq
; ============================================================
; BSS: scratch space for user RSP save
; ============================================================
section .bss
global g_userRsp
g_userRsp: resq 1