2155 lines
80 KiB
C++
2155 lines
80 KiB
C++
/*
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* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions are met:
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*
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* 1. Redistributions of source code must retain the above copyright notice, this
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* list of conditions and the following disclaimer.
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*
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* 2. Redistributions in binary form must reproduce the above copyright notice,
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* this list of conditions and the following disclaimer in the documentation
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* and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
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* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
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* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#include <AK/Assertions.h>
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#include <AK/String.h>
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#include <AK/StringBuilder.h>
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#include <AK/Types.h>
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#include <Kernel/Arch/i386/CPU.h>
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#include <Kernel/Arch/i386/ISRStubs.h>
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#include <Kernel/Arch/i386/ProcessorInfo.h>
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#include <Kernel/IO.h>
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#include <Kernel/Interrupts/APIC.h>
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#include <Kernel/Interrupts/GenericInterruptHandler.h>
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#include <Kernel/Interrupts/IRQHandler.h>
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#include <Kernel/Interrupts/InterruptManagement.h>
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#include <Kernel/Interrupts/SharedIRQHandler.h>
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#include <Kernel/Interrupts/SpuriousInterruptHandler.h>
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#include <Kernel/Interrupts/UnhandledInterruptHandler.h>
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#include <Kernel/KSyms.h>
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#include <Kernel/Process.h>
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#include <Kernel/SpinLock.h>
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#include <Kernel/Thread.h>
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#include <Kernel/VM/MemoryManager.h>
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#include <Kernel/VM/PageDirectory.h>
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#include <LibC/mallocdefs.h>
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//#define PAGE_FAULT_DEBUG
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//#define CONTEXT_SWITCH_DEBUG
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//#define SMP_DEBUG
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namespace Kernel {
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static DescriptorTablePointer s_idtr;
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static Descriptor s_idt[256];
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static GenericInterruptHandler* s_interrupt_handler[GENERIC_INTERRUPT_HANDLERS_COUNT];
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// The compiler can't see the calls to these functions inside assembly.
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// Declare them, to avoid dead code warnings.
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extern "C" void enter_thread_context(Thread* from_thread, Thread* to_thread);
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extern "C" void context_first_init(Thread* from_thread, Thread* to_thread, TrapFrame* trap);
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extern "C" u32 do_init_context(Thread* thread, u32 flags);
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extern "C" void pre_init_finished(void);
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extern "C" void post_init_finished(void);
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extern "C" void handle_interrupt(TrapFrame*);
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#define EH_ENTRY(ec, title) \
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extern "C" void title##_asm_entry(); \
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extern "C" void title##_handler(TrapFrame*); \
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asm( \
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".globl " #title "_asm_entry\n" \
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"" #title "_asm_entry: \n" \
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" pusha\n" \
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" pushl %ds\n" \
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" pushl %es\n" \
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" pushl %fs\n" \
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" pushl %gs\n" \
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" pushl %ss\n" \
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" mov $" __STRINGIFY(GDT_SELECTOR_DATA0) ", %ax\n" \
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" mov %ax, %ds\n" \
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" mov %ax, %es\n" \
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" mov $" __STRINGIFY(GDT_SELECTOR_PROC) ", %ax\n" \
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" mov %ax, %fs\n" \
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" pushl %esp \n" /* set TrapFrame::regs */ \
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" subl $" __STRINGIFY(TRAP_FRAME_SIZE - 4) ", %esp \n" \
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" pushl %esp \n" \
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" cld\n" \
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" call enter_trap_no_irq \n" \
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" call " #title "_handler\n" \
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" jmp common_trap_exit \n");
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#define EH_ENTRY_NO_CODE(ec, title) \
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extern "C" void title##_handler(TrapFrame*); \
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extern "C" void title##_asm_entry(); \
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asm( \
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".globl " #title "_asm_entry\n" \
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"" #title "_asm_entry: \n" \
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" pushl $0x0\n" \
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" pusha\n" \
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" pushl %ds\n" \
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" pushl %es\n" \
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" pushl %fs\n" \
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" pushl %gs\n" \
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" pushl %ss\n" \
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" mov $" __STRINGIFY(GDT_SELECTOR_DATA0) ", %ax\n" \
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" mov %ax, %ds\n" \
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" mov %ax, %es\n" \
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" mov $" __STRINGIFY(GDT_SELECTOR_PROC) ", %ax\n" \
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" mov %ax, %fs\n" \
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" pushl %esp \n" /* set TrapFrame::regs */ \
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" subl $" __STRINGIFY(TRAP_FRAME_SIZE - 4) ", %esp \n" \
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" pushl %esp \n" \
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" cld\n" \
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" call enter_trap_no_irq \n" \
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" call " #title "_handler\n" \
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" jmp common_trap_exit \n");
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static void dump(const RegisterState& regs)
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{
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u16 ss;
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u32 esp;
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if (!(regs.cs & 3)) {
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ss = regs.ss;
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esp = regs.esp;
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} else {
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ss = regs.userspace_ss;
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esp = regs.userspace_esp;
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}
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klog() << "exception code: " << String::format("%04x", regs.exception_code) << " (isr: " << String::format("%04x", regs.isr_number);
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klog() << " pc=" << String::format("%04x", (u16)regs.cs) << ":" << String::format("%08x", regs.eip) << " flags=" << String::format("%04x", (u16)regs.eflags);
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klog() << " stk=" << String::format("%04x", ss) << ":" << String::format("%08x", esp);
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klog() << " ds=" << String::format("%04x", (u16)regs.ds) << " es=" << String::format("%04x", (u16)regs.es) << " fs=" << String::format("%04x", (u16)regs.fs) << " gs=" << String::format("%04x", (u16)regs.gs);
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klog() << "eax=" << String::format("%08x", regs.eax) << " ebx=" << String::format("%08x", regs.ebx) << " ecx=" << String::format("%08x", regs.ecx) << " edx=" << String::format("%08x", regs.edx);
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klog() << "ebp=" << String::format("%08x", regs.ebp) << " esp=" << String::format("%08x", regs.esp) << " esi=" << String::format("%08x", regs.esi) << " edi=" << String::format("%08x", regs.edi);
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u32 cr0;
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asm("movl %%cr0, %%eax"
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: "=a"(cr0));
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u32 cr2;
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asm("movl %%cr2, %%eax"
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: "=a"(cr2));
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u32 cr3 = read_cr3();
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u32 cr4;
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asm("movl %%cr4, %%eax"
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: "=a"(cr4));
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klog() << "cr0=" << String::format("%08x", cr0) << " cr2=" << String::format("%08x", cr2) << " cr3=" << String::format("%08x", cr3) << " cr4=" << String::format("%08x", cr4);
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auto process = Process::current();
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u8 code[8];
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void* fault_at;
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if (process && safe_memcpy(code, (void*)regs.eip, 8, fault_at)) {
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SmapDisabler disabler;
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klog() << "code: " << String::format("%02x", code[0]) << " " << String::format("%02x", code[1]) << " " << String::format("%02x", code[2]) << " " << String::format("%02x", code[3]) << " " << String::format("%02x", code[4]) << " " << String::format("%02x", code[5]) << " " << String::format("%02x", code[6]) << " " << String::format("%02x", code[7]);
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}
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}
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void handle_crash(RegisterState& regs, const char* description, int signal, bool out_of_memory)
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{
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auto process = Process::current();
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if (!process) {
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klog() << description << " with !current";
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Processor::halt();
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}
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// If a process crashed while inspecting another process,
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// make sure we switch back to the right page tables.
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MM.enter_process_paging_scope(*process);
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klog() << "CRASH: CPU #" << Processor::current().id() << " " << description << ". Ring " << (regs.cs & 3) << ".";
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dump(regs);
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if (!(regs.cs & 3)) {
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klog() << "Crash in ring 0 :(";
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dump_backtrace();
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Processor::halt();
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}
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cli();
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process->crash(signal, regs.eip, out_of_memory);
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}
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EH_ENTRY_NO_CODE(6, illegal_instruction);
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void illegal_instruction_handler(TrapFrame* trap)
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{
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clac();
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handle_crash(*trap->regs, "Illegal instruction", SIGILL);
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}
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EH_ENTRY_NO_CODE(0, divide_error);
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void divide_error_handler(TrapFrame* trap)
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{
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clac();
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handle_crash(*trap->regs, "Divide error", SIGFPE);
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}
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EH_ENTRY(13, general_protection_fault);
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void general_protection_fault_handler(TrapFrame* trap)
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{
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clac();
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handle_crash(*trap->regs, "General protection fault", SIGSEGV);
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}
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// 7: FPU not available exception
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EH_ENTRY_NO_CODE(7, fpu_exception);
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void fpu_exception_handler(TrapFrame*)
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{
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// Just clear the TS flag. We've already restored the FPU state eagerly.
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// FIXME: It would be nice if we didn't have to do this at all.
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asm volatile("clts");
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}
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extern "C" u8* safe_memcpy_ins_1;
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extern "C" u8* safe_memcpy_1_faulted;
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extern "C" u8* safe_memcpy_ins_2;
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extern "C" u8* safe_memcpy_2_faulted;
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extern "C" u8* safe_strnlen_ins;
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extern "C" u8* safe_strnlen_faulted;
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extern "C" u8* safe_memset_ins_1;
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extern "C" u8* safe_memset_1_faulted;
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extern "C" u8* safe_memset_ins_2;
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extern "C" u8* safe_memset_2_faulted;
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bool safe_memcpy(void* dest_ptr, const void* src_ptr, size_t n, void*& fault_at)
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{
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fault_at = nullptr;
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size_t dest = (size_t)dest_ptr;
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size_t src = (size_t)src_ptr;
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size_t remainder;
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// FIXME: Support starting at an unaligned address.
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if (!(dest & 0x3) && !(src & 0x3) && n >= 12) {
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size_t size_ts = n / sizeof(size_t);
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asm volatile(
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".global safe_memcpy_ins_1 \n"
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"safe_memcpy_ins_1: \n"
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"rep movsl \n"
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".global safe_memcpy_1_faulted \n"
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"safe_memcpy_1_faulted: \n" // handle_safe_access_fault() set edx to the fault address!
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: "=S" (src),
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"=D" (dest),
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"=c" (remainder),
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[fault_at] "=d" (fault_at)
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: "S" (src),
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"D" (dest),
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"c" (size_ts)
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: "memory");
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if (remainder != 0)
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return false; // fault_at is already set!
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n -= size_ts * sizeof(size_t);
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if (n == 0) {
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fault_at = nullptr;
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return true;
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}
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}
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asm volatile(
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".global safe_memcpy_ins_2 \n"
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"safe_memcpy_ins_2: \n"
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"rep movsb \n"
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".global safe_memcpy_2_faulted \n"
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"safe_memcpy_2_faulted: \n" // handle_safe_access_fault() set edx to the fault address!
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: "=c" (remainder),
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[fault_at] "=d" (fault_at)
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: "S" (src),
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"D" (dest),
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"c" (n)
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: "memory");
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if (remainder != 0)
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return false; // fault_at is already set!
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fault_at = nullptr;
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return true;
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}
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ssize_t safe_strnlen(const char* str, size_t max_n, void*& fault_at)
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{
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ssize_t count = 0;
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fault_at = nullptr;
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asm volatile(
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"1: \n"
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"test %[max_n], %[max_n] \n"
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"je 2f \n"
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"dec %[max_n] \n"
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".global safe_strnlen_ins \n"
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"safe_strnlen_ins: \n"
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"cmpb $0,(%[str], %[count], 1) \n"
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"je 2f \n"
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"inc %[count] \n"
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"jmp 1b \n"
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".global safe_strnlen_faulted \n"
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"safe_strnlen_faulted: \n" // handle_safe_access_fault() set edx to the fault address!
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"xor %[count_on_error], %[count_on_error] \n"
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"dec %[count_on_error] \n" // return -1 on fault
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"2:"
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: [count_on_error] "=c" (count),
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[fault_at] "=d" (fault_at)
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: [str] "b" (str),
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[count] "c" (count),
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[max_n] "d" (max_n)
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);
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if (count >= 0)
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fault_at = nullptr;
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return count;
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}
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bool safe_memset(void* dest_ptr, int c, size_t n, void*& fault_at)
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{
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fault_at = nullptr;
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size_t dest = (size_t)dest_ptr;
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size_t remainder;
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// FIXME: Support starting at an unaligned address.
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if (!(dest & 0x3) && n >= 12) {
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size_t size_ts = n / sizeof(size_t);
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size_t expanded_c = (u8)c;
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expanded_c |= expanded_c << 8;
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expanded_c |= expanded_c << 16;
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asm volatile(
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".global safe_memset_ins_1 \n"
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"safe_memset_ins_1: \n"
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"rep stosl \n"
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".global safe_memset_1_faulted \n"
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"safe_memset_1_faulted: \n" // handle_safe_access_fault() set edx to the fault address!
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: "=D" (dest),
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"=c" (remainder),
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[fault_at] "=d" (fault_at)
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: "D" (dest),
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"a" (expanded_c),
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"c" (size_ts)
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: "memory");
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if (remainder != 0)
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return false; // fault_at is already set!
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n -= size_ts * sizeof(size_t);
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if (remainder == 0) {
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fault_at = nullptr;
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return true;
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}
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}
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asm volatile(
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".global safe_memset_ins_2 \n"
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"safe_memset_ins_2: \n"
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"rep stosb \n"
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".global safe_memset_2_faulted \n"
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"safe_memset_2_faulted: \n" // handle_safe_access_fault() set edx to the fault address!
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: "=D" (dest),
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"=c" (remainder),
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[fault_at] "=d" (fault_at)
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: "D" (dest),
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"c" (n),
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"a" (c)
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: "memory");
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if (remainder != 0)
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return false; // fault_at is already set!
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fault_at = nullptr;
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return true;
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}
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static bool handle_safe_access_fault(RegisterState& regs, u32 fault_address)
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{
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// If we detect that the fault happened in safe_memcpy() safe_strnlen(),
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// or safe_memset() then resume at the appropriate _faulted label
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if (regs.eip == (FlatPtr)&safe_memcpy_ins_1)
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regs.eip = (FlatPtr)&safe_memcpy_1_faulted;
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else if (regs.eip == (FlatPtr)&safe_memcpy_ins_2)
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regs.eip = (FlatPtr)&safe_memcpy_2_faulted;
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else if (regs.eip == (FlatPtr)&safe_strnlen_ins)
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regs.eip = (FlatPtr)&safe_strnlen_faulted;
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else if (regs.eip == (FlatPtr)&safe_memset_ins_1)
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regs.eip = (FlatPtr)&safe_memset_1_faulted;
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else if (regs.eip == (FlatPtr)&safe_memset_ins_2)
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regs.eip = (FlatPtr)&safe_memset_2_faulted;
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else
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return false;
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regs.edx = fault_address;
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return true;
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}
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// 14: Page Fault
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EH_ENTRY(14, page_fault);
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void page_fault_handler(TrapFrame* trap)
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{
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clac();
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auto& regs = *trap->regs;
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u32 fault_address;
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asm("movl %%cr2, %%eax"
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: "=a"(fault_address));
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#ifdef PAGE_FAULT_DEBUG
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u32 fault_page_directory = read_cr3();
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dbg() << "CPU #" << (Processor::is_initialized() ? Processor::current().id() : 0) << " ring " << (regs.cs & 3)
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<< " " << (regs.exception_code & 1 ? "PV" : "NP")
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<< " page fault in PD=" << String::format("%x", fault_page_directory) << ", "
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<< (regs.exception_code & 8 ? "reserved-bit " : "")
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<< (regs.exception_code & 2 ? "write" : "read")
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<< " " << VirtualAddress(fault_address);
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#endif
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#ifdef PAGE_FAULT_DEBUG
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dump(regs);
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#endif
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bool faulted_in_kernel = !(regs.cs & 3);
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if (faulted_in_kernel && Processor::current().in_irq()) {
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// If we're faulting in an IRQ handler, first check if we failed
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// due to safe_memcpy, safe_strnlen, or safe_memset. If we did,
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// gracefully continue immediately. Because we're in an IRQ handler
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// we can't really try to resolve the page fault in a meaningful
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// way, so we need to do this before calling into
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// MemoryManager::handle_page_fault, which would just bail and
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// request a crash
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if (handle_safe_access_fault(regs, fault_address))
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return;
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}
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auto current_thread = Thread::current();
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if (!faulted_in_kernel && !MM.validate_user_stack(current_thread->process(), VirtualAddress(regs.userspace_esp))) {
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dbg() << "Invalid stack pointer: " << VirtualAddress(regs.userspace_esp);
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handle_crash(regs, "Bad stack on page fault", SIGSTKFLT);
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ASSERT_NOT_REACHED();
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}
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auto response = MM.handle_page_fault(PageFault(regs.exception_code, VirtualAddress(fault_address)));
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if (response == PageFaultResponse::ShouldCrash || response == PageFaultResponse::OutOfMemory) {
|
|
if (faulted_in_kernel && handle_safe_access_fault(regs, fault_address)) {
|
|
// If this would be a ring0 (kernel) fault and the fault was triggered by
|
|
// safe_memcpy, safe_strnlen, or safe_memset then we resume execution at
|
|
// the appropriate _fault label rather than crashing
|
|
return;
|
|
}
|
|
|
|
if (response != PageFaultResponse::OutOfMemory) {
|
|
if (current_thread->has_signal_handler(SIGSEGV)) {
|
|
current_thread->send_urgent_signal_to_self(SIGSEGV);
|
|
return;
|
|
}
|
|
}
|
|
|
|
dbg() << "Unrecoverable page fault, "
|
|
<< (regs.exception_code & PageFaultFlags::ReservedBitViolation ? "reserved bit violation / " : "")
|
|
<< (regs.exception_code & PageFaultFlags::InstructionFetch ? "instruction fetch / " : "")
|
|
<< (regs.exception_code & PageFaultFlags::Write ? "write to" : "read from")
|
|
<< " address " << VirtualAddress(fault_address);
|
|
u32 malloc_scrub_pattern = explode_byte(MALLOC_SCRUB_BYTE);
|
|
u32 free_scrub_pattern = explode_byte(FREE_SCRUB_BYTE);
|
|
u32 kmalloc_scrub_pattern = explode_byte(KMALLOC_SCRUB_BYTE);
|
|
u32 kfree_scrub_pattern = explode_byte(KFREE_SCRUB_BYTE);
|
|
u32 slab_alloc_scrub_pattern = explode_byte(SLAB_ALLOC_SCRUB_BYTE);
|
|
u32 slab_dealloc_scrub_pattern = explode_byte(SLAB_DEALLOC_SCRUB_BYTE);
|
|
if ((fault_address & 0xffff0000) == (malloc_scrub_pattern & 0xffff0000)) {
|
|
dbg() << "Note: Address " << VirtualAddress(fault_address) << " looks like it may be uninitialized malloc() memory";
|
|
} else if ((fault_address & 0xffff0000) == (free_scrub_pattern & 0xffff0000)) {
|
|
dbg() << "Note: Address " << VirtualAddress(fault_address) << " looks like it may be recently free()'d memory";
|
|
} else if ((fault_address & 0xffff0000) == (kmalloc_scrub_pattern & 0xffff0000)) {
|
|
dbg() << "Note: Address " << VirtualAddress(fault_address) << " looks like it may be uninitialized kmalloc() memory";
|
|
} else if ((fault_address & 0xffff0000) == (kfree_scrub_pattern & 0xffff0000)) {
|
|
dbg() << "Note: Address " << VirtualAddress(fault_address) << " looks like it may be recently kfree()'d memory";
|
|
} else if ((fault_address & 0xffff0000) == (slab_alloc_scrub_pattern & 0xffff0000)) {
|
|
dbg() << "Note: Address " << VirtualAddress(fault_address) << " looks like it may be uninitialized slab_alloc() memory";
|
|
} else if ((fault_address & 0xffff0000) == (slab_dealloc_scrub_pattern & 0xffff0000)) {
|
|
dbg() << "Note: Address " << VirtualAddress(fault_address) << " looks like it may be recently slab_dealloc()'d memory";
|
|
} else if (fault_address < 4096) {
|
|
dbg() << "Note: Address " << VirtualAddress(fault_address) << " looks like a possible nullptr dereference";
|
|
}
|
|
|
|
handle_crash(regs, "Page Fault", SIGSEGV, response == PageFaultResponse::OutOfMemory);
|
|
} else if (response == PageFaultResponse::Continue) {
|
|
#ifdef PAGE_FAULT_DEBUG
|
|
dbg() << "Continuing after resolved page fault";
|
|
#endif
|
|
} else {
|
|
ASSERT_NOT_REACHED();
|
|
}
|
|
}
|
|
|
|
EH_ENTRY_NO_CODE(1, debug);
|
|
void debug_handler(TrapFrame* trap)
|
|
{
|
|
clac();
|
|
auto& regs = *trap->regs;
|
|
auto current_thread = Thread::current();
|
|
if (¤t_thread->process() == nullptr || (regs.cs & 3) == 0) {
|
|
klog() << "Debug Exception in Ring0";
|
|
Processor::halt();
|
|
return;
|
|
}
|
|
constexpr u8 REASON_SINGLESTEP = 14;
|
|
bool is_reason_singlestep = (read_dr6() & (1 << REASON_SINGLESTEP));
|
|
if (!is_reason_singlestep)
|
|
return;
|
|
|
|
if (current_thread->tracer()) {
|
|
current_thread->tracer()->set_regs(regs);
|
|
}
|
|
current_thread->send_urgent_signal_to_self(SIGTRAP);
|
|
}
|
|
|
|
EH_ENTRY_NO_CODE(3, breakpoint);
|
|
void breakpoint_handler(TrapFrame* trap)
|
|
{
|
|
clac();
|
|
auto& regs = *trap->regs;
|
|
auto current_thread = Thread::current();
|
|
if (¤t_thread->process() == nullptr || (regs.cs & 3) == 0) {
|
|
klog() << "Breakpoint Trap in Ring0";
|
|
Processor::halt();
|
|
return;
|
|
}
|
|
if (current_thread->tracer()) {
|
|
current_thread->tracer()->set_regs(regs);
|
|
}
|
|
current_thread->send_urgent_signal_to_self(SIGTRAP);
|
|
}
|
|
|
|
#define EH(i, msg) \
|
|
static void _exception##i() \
|
|
{ \
|
|
klog() << msg; \
|
|
u32 cr0, cr2, cr3, cr4; \
|
|
asm("movl %%cr0, %%eax" \
|
|
: "=a"(cr0)); \
|
|
asm("movl %%cr2, %%eax" \
|
|
: "=a"(cr2)); \
|
|
asm("movl %%cr3, %%eax" \
|
|
: "=a"(cr3)); \
|
|
asm("movl %%cr4, %%eax" \
|
|
: "=a"(cr4)); \
|
|
klog() << "CR0=" << String::format("%x", cr0) << " CR2=" << String::format("%x", cr2) << " CR3=" << String::format("%x", cr3) << " CR4=" << String::format("%x", cr4); \
|
|
Processor::halt(); \
|
|
}
|
|
|
|
EH(2, "Unknown error")
|
|
EH(4, "Overflow")
|
|
EH(5, "Bounds check")
|
|
EH(8, "Double fault")
|
|
EH(9, "Coprocessor segment overrun")
|
|
EH(10, "Invalid TSS")
|
|
EH(11, "Segment not present")
|
|
EH(12, "Stack exception")
|
|
EH(15, "Unknown error")
|
|
EH(16, "Coprocessor error")
|
|
|
|
const DescriptorTablePointer& get_idtr()
|
|
{
|
|
return s_idtr;
|
|
}
|
|
|
|
static void unimp_trap()
|
|
{
|
|
klog() << "Unhandled IRQ.";
|
|
Processor::Processor::halt();
|
|
}
|
|
|
|
GenericInterruptHandler& get_interrupt_handler(u8 interrupt_number)
|
|
{
|
|
ASSERT(s_interrupt_handler[interrupt_number] != nullptr);
|
|
return *s_interrupt_handler[interrupt_number];
|
|
}
|
|
|
|
static void revert_to_unused_handler(u8 interrupt_number)
|
|
{
|
|
new UnhandledInterruptHandler(interrupt_number);
|
|
}
|
|
|
|
void register_generic_interrupt_handler(u8 interrupt_number, GenericInterruptHandler& handler)
|
|
{
|
|
ASSERT(interrupt_number < GENERIC_INTERRUPT_HANDLERS_COUNT);
|
|
if (s_interrupt_handler[interrupt_number] != nullptr) {
|
|
if (s_interrupt_handler[interrupt_number]->type() == HandlerType::UnhandledInterruptHandler) {
|
|
s_interrupt_handler[interrupt_number] = &handler;
|
|
return;
|
|
}
|
|
if (s_interrupt_handler[interrupt_number]->is_shared_handler() && !s_interrupt_handler[interrupt_number]->is_sharing_with_others()) {
|
|
ASSERT(s_interrupt_handler[interrupt_number]->type() == HandlerType::SharedIRQHandler);
|
|
static_cast<SharedIRQHandler*>(s_interrupt_handler[interrupt_number])->register_handler(handler);
|
|
return;
|
|
}
|
|
if (!s_interrupt_handler[interrupt_number]->is_shared_handler()) {
|
|
ASSERT(s_interrupt_handler[interrupt_number]->type() == HandlerType::IRQHandler);
|
|
auto& previous_handler = *s_interrupt_handler[interrupt_number];
|
|
s_interrupt_handler[interrupt_number] = nullptr;
|
|
SharedIRQHandler::initialize(interrupt_number);
|
|
static_cast<SharedIRQHandler*>(s_interrupt_handler[interrupt_number])->register_handler(previous_handler);
|
|
static_cast<SharedIRQHandler*>(s_interrupt_handler[interrupt_number])->register_handler(handler);
|
|
return;
|
|
}
|
|
ASSERT_NOT_REACHED();
|
|
} else {
|
|
s_interrupt_handler[interrupt_number] = &handler;
|
|
}
|
|
}
|
|
|
|
void unregister_generic_interrupt_handler(u8 interrupt_number, GenericInterruptHandler& handler)
|
|
{
|
|
ASSERT(s_interrupt_handler[interrupt_number] != nullptr);
|
|
if (s_interrupt_handler[interrupt_number]->type() == HandlerType::UnhandledInterruptHandler) {
|
|
dbg() << "Trying to unregister unused handler (?)";
|
|
return;
|
|
}
|
|
if (s_interrupt_handler[interrupt_number]->is_shared_handler() && !s_interrupt_handler[interrupt_number]->is_sharing_with_others()) {
|
|
ASSERT(s_interrupt_handler[interrupt_number]->type() == HandlerType::SharedIRQHandler);
|
|
static_cast<SharedIRQHandler*>(s_interrupt_handler[interrupt_number])->unregister_handler(handler);
|
|
if (!static_cast<SharedIRQHandler*>(s_interrupt_handler[interrupt_number])->sharing_devices_count()) {
|
|
revert_to_unused_handler(interrupt_number);
|
|
}
|
|
return;
|
|
}
|
|
if (!s_interrupt_handler[interrupt_number]->is_shared_handler()) {
|
|
ASSERT(s_interrupt_handler[interrupt_number]->type() == HandlerType::IRQHandler);
|
|
revert_to_unused_handler(interrupt_number);
|
|
return;
|
|
}
|
|
ASSERT_NOT_REACHED();
|
|
}
|
|
|
|
void register_interrupt_handler(u8 index, void (*f)())
|
|
{
|
|
s_idt[index].low = 0x00080000 | LSW((f));
|
|
s_idt[index].high = ((u32)(f)&0xffff0000) | 0x8e00;
|
|
}
|
|
|
|
void register_user_callable_interrupt_handler(u8 index, void (*f)())
|
|
{
|
|
s_idt[index].low = 0x00080000 | LSW((f));
|
|
s_idt[index].high = ((u32)(f)&0xffff0000) | 0xef00;
|
|
}
|
|
|
|
void flush_idt()
|
|
{
|
|
asm("lidt %0" ::"m"(s_idtr));
|
|
}
|
|
|
|
static void idt_init()
|
|
{
|
|
s_idtr.address = s_idt;
|
|
s_idtr.limit = 256 * 8 - 1;
|
|
|
|
register_interrupt_handler(0x00, divide_error_asm_entry);
|
|
register_user_callable_interrupt_handler(0x01, debug_asm_entry);
|
|
register_interrupt_handler(0x02, _exception2);
|
|
register_user_callable_interrupt_handler(0x03, breakpoint_asm_entry);
|
|
register_interrupt_handler(0x04, _exception4);
|
|
register_interrupt_handler(0x05, _exception5);
|
|
register_interrupt_handler(0x06, illegal_instruction_asm_entry);
|
|
register_interrupt_handler(0x07, fpu_exception_asm_entry);
|
|
register_interrupt_handler(0x08, _exception8);
|
|
register_interrupt_handler(0x09, _exception9);
|
|
register_interrupt_handler(0x0a, _exception10);
|
|
register_interrupt_handler(0x0b, _exception11);
|
|
register_interrupt_handler(0x0c, _exception12);
|
|
register_interrupt_handler(0x0d, general_protection_fault_asm_entry);
|
|
register_interrupt_handler(0x0e, page_fault_asm_entry);
|
|
register_interrupt_handler(0x0f, _exception15);
|
|
register_interrupt_handler(0x10, _exception16);
|
|
|
|
for (u8 i = 0x11; i < 0x50; i++)
|
|
register_interrupt_handler(i, unimp_trap);
|
|
|
|
register_interrupt_handler(0x50, interrupt_80_asm_entry);
|
|
register_interrupt_handler(0x51, interrupt_81_asm_entry);
|
|
register_interrupt_handler(0x52, interrupt_82_asm_entry);
|
|
register_interrupt_handler(0x53, interrupt_83_asm_entry);
|
|
register_interrupt_handler(0x54, interrupt_84_asm_entry);
|
|
register_interrupt_handler(0x55, interrupt_85_asm_entry);
|
|
register_interrupt_handler(0x56, interrupt_86_asm_entry);
|
|
register_interrupt_handler(0x57, interrupt_87_asm_entry);
|
|
register_interrupt_handler(0x58, interrupt_88_asm_entry);
|
|
register_interrupt_handler(0x59, interrupt_89_asm_entry);
|
|
register_interrupt_handler(0x5a, interrupt_90_asm_entry);
|
|
register_interrupt_handler(0x5b, interrupt_91_asm_entry);
|
|
register_interrupt_handler(0x5c, interrupt_92_asm_entry);
|
|
register_interrupt_handler(0x5d, interrupt_93_asm_entry);
|
|
register_interrupt_handler(0x5e, interrupt_94_asm_entry);
|
|
register_interrupt_handler(0x5f, interrupt_95_asm_entry);
|
|
register_interrupt_handler(0x60, interrupt_96_asm_entry);
|
|
register_interrupt_handler(0x61, interrupt_97_asm_entry);
|
|
register_interrupt_handler(0x62, interrupt_98_asm_entry);
|
|
register_interrupt_handler(0x63, interrupt_99_asm_entry);
|
|
register_interrupt_handler(0x64, interrupt_100_asm_entry);
|
|
register_interrupt_handler(0x65, interrupt_101_asm_entry);
|
|
register_interrupt_handler(0x66, interrupt_102_asm_entry);
|
|
register_interrupt_handler(0x67, interrupt_103_asm_entry);
|
|
register_interrupt_handler(0x68, interrupt_104_asm_entry);
|
|
register_interrupt_handler(0x69, interrupt_105_asm_entry);
|
|
register_interrupt_handler(0x6a, interrupt_106_asm_entry);
|
|
register_interrupt_handler(0x6b, interrupt_107_asm_entry);
|
|
register_interrupt_handler(0x6c, interrupt_108_asm_entry);
|
|
register_interrupt_handler(0x6d, interrupt_109_asm_entry);
|
|
register_interrupt_handler(0x6e, interrupt_110_asm_entry);
|
|
register_interrupt_handler(0x6f, interrupt_111_asm_entry);
|
|
register_interrupt_handler(0x70, interrupt_112_asm_entry);
|
|
register_interrupt_handler(0x71, interrupt_113_asm_entry);
|
|
register_interrupt_handler(0x72, interrupt_114_asm_entry);
|
|
register_interrupt_handler(0x73, interrupt_115_asm_entry);
|
|
register_interrupt_handler(0x74, interrupt_116_asm_entry);
|
|
register_interrupt_handler(0x75, interrupt_117_asm_entry);
|
|
register_interrupt_handler(0x76, interrupt_118_asm_entry);
|
|
register_interrupt_handler(0x77, interrupt_119_asm_entry);
|
|
register_interrupt_handler(0x78, interrupt_120_asm_entry);
|
|
register_interrupt_handler(0x79, interrupt_121_asm_entry);
|
|
register_interrupt_handler(0x7a, interrupt_122_asm_entry);
|
|
register_interrupt_handler(0x7b, interrupt_123_asm_entry);
|
|
register_interrupt_handler(0x7c, interrupt_124_asm_entry);
|
|
register_interrupt_handler(0x7d, interrupt_125_asm_entry);
|
|
register_interrupt_handler(0x7e, interrupt_126_asm_entry);
|
|
register_interrupt_handler(0x7f, interrupt_127_asm_entry);
|
|
register_interrupt_handler(0x80, interrupt_128_asm_entry);
|
|
register_interrupt_handler(0x81, interrupt_129_asm_entry);
|
|
register_interrupt_handler(0x82, interrupt_130_asm_entry);
|
|
register_interrupt_handler(0x83, interrupt_131_asm_entry);
|
|
register_interrupt_handler(0x84, interrupt_132_asm_entry);
|
|
register_interrupt_handler(0x85, interrupt_133_asm_entry);
|
|
register_interrupt_handler(0x86, interrupt_134_asm_entry);
|
|
register_interrupt_handler(0x87, interrupt_135_asm_entry);
|
|
register_interrupt_handler(0x88, interrupt_136_asm_entry);
|
|
register_interrupt_handler(0x89, interrupt_137_asm_entry);
|
|
register_interrupt_handler(0x8a, interrupt_138_asm_entry);
|
|
register_interrupt_handler(0x8b, interrupt_139_asm_entry);
|
|
register_interrupt_handler(0x8c, interrupt_140_asm_entry);
|
|
register_interrupt_handler(0x8d, interrupt_141_asm_entry);
|
|
register_interrupt_handler(0x8e, interrupt_142_asm_entry);
|
|
register_interrupt_handler(0x8f, interrupt_143_asm_entry);
|
|
register_interrupt_handler(0x90, interrupt_144_asm_entry);
|
|
register_interrupt_handler(0x91, interrupt_145_asm_entry);
|
|
register_interrupt_handler(0x92, interrupt_146_asm_entry);
|
|
register_interrupt_handler(0x93, interrupt_147_asm_entry);
|
|
register_interrupt_handler(0x94, interrupt_148_asm_entry);
|
|
register_interrupt_handler(0x95, interrupt_149_asm_entry);
|
|
register_interrupt_handler(0x96, interrupt_150_asm_entry);
|
|
register_interrupt_handler(0x97, interrupt_151_asm_entry);
|
|
register_interrupt_handler(0x98, interrupt_152_asm_entry);
|
|
register_interrupt_handler(0x99, interrupt_153_asm_entry);
|
|
register_interrupt_handler(0x9a, interrupt_154_asm_entry);
|
|
register_interrupt_handler(0x9b, interrupt_155_asm_entry);
|
|
register_interrupt_handler(0x9c, interrupt_156_asm_entry);
|
|
register_interrupt_handler(0x9d, interrupt_157_asm_entry);
|
|
register_interrupt_handler(0x9e, interrupt_158_asm_entry);
|
|
register_interrupt_handler(0x9f, interrupt_159_asm_entry);
|
|
register_interrupt_handler(0xa0, interrupt_160_asm_entry);
|
|
register_interrupt_handler(0xa1, interrupt_161_asm_entry);
|
|
register_interrupt_handler(0xa2, interrupt_162_asm_entry);
|
|
register_interrupt_handler(0xa3, interrupt_163_asm_entry);
|
|
register_interrupt_handler(0xa4, interrupt_164_asm_entry);
|
|
register_interrupt_handler(0xa5, interrupt_165_asm_entry);
|
|
register_interrupt_handler(0xa6, interrupt_166_asm_entry);
|
|
register_interrupt_handler(0xa7, interrupt_167_asm_entry);
|
|
register_interrupt_handler(0xa8, interrupt_168_asm_entry);
|
|
register_interrupt_handler(0xa9, interrupt_169_asm_entry);
|
|
register_interrupt_handler(0xaa, interrupt_170_asm_entry);
|
|
register_interrupt_handler(0xab, interrupt_171_asm_entry);
|
|
register_interrupt_handler(0xac, interrupt_172_asm_entry);
|
|
register_interrupt_handler(0xad, interrupt_173_asm_entry);
|
|
register_interrupt_handler(0xae, interrupt_174_asm_entry);
|
|
register_interrupt_handler(0xaf, interrupt_175_asm_entry);
|
|
register_interrupt_handler(0xb0, interrupt_176_asm_entry);
|
|
register_interrupt_handler(0xb1, interrupt_177_asm_entry);
|
|
register_interrupt_handler(0xb2, interrupt_178_asm_entry);
|
|
register_interrupt_handler(0xb3, interrupt_179_asm_entry);
|
|
register_interrupt_handler(0xb4, interrupt_180_asm_entry);
|
|
register_interrupt_handler(0xb5, interrupt_181_asm_entry);
|
|
register_interrupt_handler(0xb6, interrupt_182_asm_entry);
|
|
register_interrupt_handler(0xb7, interrupt_183_asm_entry);
|
|
register_interrupt_handler(0xb8, interrupt_184_asm_entry);
|
|
register_interrupt_handler(0xb9, interrupt_185_asm_entry);
|
|
register_interrupt_handler(0xba, interrupt_186_asm_entry);
|
|
register_interrupt_handler(0xbb, interrupt_187_asm_entry);
|
|
register_interrupt_handler(0xbc, interrupt_188_asm_entry);
|
|
register_interrupt_handler(0xbd, interrupt_189_asm_entry);
|
|
register_interrupt_handler(0xbe, interrupt_190_asm_entry);
|
|
register_interrupt_handler(0xbf, interrupt_191_asm_entry);
|
|
register_interrupt_handler(0xc0, interrupt_192_asm_entry);
|
|
register_interrupt_handler(0xc1, interrupt_193_asm_entry);
|
|
register_interrupt_handler(0xc2, interrupt_194_asm_entry);
|
|
register_interrupt_handler(0xc3, interrupt_195_asm_entry);
|
|
register_interrupt_handler(0xc4, interrupt_196_asm_entry);
|
|
register_interrupt_handler(0xc5, interrupt_197_asm_entry);
|
|
register_interrupt_handler(0xc6, interrupt_198_asm_entry);
|
|
register_interrupt_handler(0xc7, interrupt_199_asm_entry);
|
|
register_interrupt_handler(0xc8, interrupt_200_asm_entry);
|
|
register_interrupt_handler(0xc9, interrupt_201_asm_entry);
|
|
register_interrupt_handler(0xca, interrupt_202_asm_entry);
|
|
register_interrupt_handler(0xcb, interrupt_203_asm_entry);
|
|
register_interrupt_handler(0xcc, interrupt_204_asm_entry);
|
|
register_interrupt_handler(0xcd, interrupt_205_asm_entry);
|
|
register_interrupt_handler(0xce, interrupt_206_asm_entry);
|
|
register_interrupt_handler(0xcf, interrupt_207_asm_entry);
|
|
register_interrupt_handler(0xd0, interrupt_208_asm_entry);
|
|
register_interrupt_handler(0xd1, interrupt_209_asm_entry);
|
|
register_interrupt_handler(0xd2, interrupt_210_asm_entry);
|
|
register_interrupt_handler(0xd3, interrupt_211_asm_entry);
|
|
register_interrupt_handler(0xd4, interrupt_212_asm_entry);
|
|
register_interrupt_handler(0xd5, interrupt_213_asm_entry);
|
|
register_interrupt_handler(0xd6, interrupt_214_asm_entry);
|
|
register_interrupt_handler(0xd7, interrupt_215_asm_entry);
|
|
register_interrupt_handler(0xd8, interrupt_216_asm_entry);
|
|
register_interrupt_handler(0xd9, interrupt_217_asm_entry);
|
|
register_interrupt_handler(0xda, interrupt_218_asm_entry);
|
|
register_interrupt_handler(0xdb, interrupt_219_asm_entry);
|
|
register_interrupt_handler(0xdc, interrupt_220_asm_entry);
|
|
register_interrupt_handler(0xdd, interrupt_221_asm_entry);
|
|
register_interrupt_handler(0xde, interrupt_222_asm_entry);
|
|
register_interrupt_handler(0xdf, interrupt_223_asm_entry);
|
|
register_interrupt_handler(0xe0, interrupt_224_asm_entry);
|
|
register_interrupt_handler(0xe1, interrupt_225_asm_entry);
|
|
register_interrupt_handler(0xe2, interrupt_226_asm_entry);
|
|
register_interrupt_handler(0xe3, interrupt_227_asm_entry);
|
|
register_interrupt_handler(0xe4, interrupt_228_asm_entry);
|
|
register_interrupt_handler(0xe5, interrupt_229_asm_entry);
|
|
register_interrupt_handler(0xe6, interrupt_230_asm_entry);
|
|
register_interrupt_handler(0xe7, interrupt_231_asm_entry);
|
|
register_interrupt_handler(0xe8, interrupt_232_asm_entry);
|
|
register_interrupt_handler(0xe9, interrupt_233_asm_entry);
|
|
register_interrupt_handler(0xea, interrupt_234_asm_entry);
|
|
register_interrupt_handler(0xeb, interrupt_235_asm_entry);
|
|
register_interrupt_handler(0xec, interrupt_236_asm_entry);
|
|
register_interrupt_handler(0xed, interrupt_237_asm_entry);
|
|
register_interrupt_handler(0xee, interrupt_238_asm_entry);
|
|
register_interrupt_handler(0xef, interrupt_239_asm_entry);
|
|
register_interrupt_handler(0xf0, interrupt_240_asm_entry);
|
|
register_interrupt_handler(0xf1, interrupt_241_asm_entry);
|
|
register_interrupt_handler(0xf2, interrupt_242_asm_entry);
|
|
register_interrupt_handler(0xf3, interrupt_243_asm_entry);
|
|
register_interrupt_handler(0xf4, interrupt_244_asm_entry);
|
|
register_interrupt_handler(0xf5, interrupt_245_asm_entry);
|
|
register_interrupt_handler(0xf6, interrupt_246_asm_entry);
|
|
register_interrupt_handler(0xf7, interrupt_247_asm_entry);
|
|
register_interrupt_handler(0xf8, interrupt_248_asm_entry);
|
|
register_interrupt_handler(0xf9, interrupt_249_asm_entry);
|
|
register_interrupt_handler(0xfa, interrupt_250_asm_entry);
|
|
register_interrupt_handler(0xfb, interrupt_251_asm_entry);
|
|
register_interrupt_handler(0xfc, interrupt_252_asm_entry);
|
|
register_interrupt_handler(0xfd, interrupt_253_asm_entry);
|
|
register_interrupt_handler(0xfe, interrupt_254_asm_entry);
|
|
register_interrupt_handler(0xff, interrupt_255_asm_entry);
|
|
|
|
dbg() << "Installing Unhandled Handlers";
|
|
|
|
for (u8 i = 0; i < GENERIC_INTERRUPT_HANDLERS_COUNT; ++i) {
|
|
new UnhandledInterruptHandler(i);
|
|
}
|
|
|
|
flush_idt();
|
|
}
|
|
|
|
void load_task_register(u16 selector)
|
|
{
|
|
asm("ltr %0" ::"r"(selector));
|
|
}
|
|
|
|
void handle_interrupt(TrapFrame* trap)
|
|
{
|
|
clac();
|
|
auto& regs = *trap->regs;
|
|
ASSERT(regs.isr_number >= IRQ_VECTOR_BASE && regs.isr_number <= (IRQ_VECTOR_BASE + GENERIC_INTERRUPT_HANDLERS_COUNT));
|
|
u8 irq = (u8)(regs.isr_number - 0x50);
|
|
ASSERT(s_interrupt_handler[irq]);
|
|
s_interrupt_handler[irq]->handle_interrupt(regs);
|
|
s_interrupt_handler[irq]->eoi();
|
|
}
|
|
|
|
void enter_trap_no_irq(TrapFrame* trap)
|
|
{
|
|
Processor::current().enter_trap(*trap, false);
|
|
}
|
|
|
|
void enter_trap(TrapFrame* trap)
|
|
{
|
|
Processor::current().enter_trap(*trap, true);
|
|
}
|
|
|
|
void exit_trap(TrapFrame* trap)
|
|
{
|
|
return Processor::current().exit_trap(*trap);
|
|
}
|
|
|
|
static void sse_init()
|
|
{
|
|
asm volatile(
|
|
"mov %cr0, %eax\n"
|
|
"andl $0xfffffffb, %eax\n"
|
|
"orl $0x2, %eax\n"
|
|
"mov %eax, %cr0\n"
|
|
"mov %cr4, %eax\n"
|
|
"orl $0x600, %eax\n"
|
|
"mov %eax, %cr4\n");
|
|
}
|
|
|
|
u32 read_cr0()
|
|
{
|
|
u32 cr0;
|
|
asm("movl %%cr0, %%eax"
|
|
: "=a"(cr0));
|
|
return cr0;
|
|
}
|
|
|
|
u32 read_cr3()
|
|
{
|
|
u32 cr3;
|
|
asm("movl %%cr3, %%eax"
|
|
: "=a"(cr3));
|
|
return cr3;
|
|
}
|
|
|
|
void write_cr3(u32 cr3)
|
|
{
|
|
asm volatile("movl %%eax, %%cr3" ::"a"(cr3)
|
|
: "memory");
|
|
}
|
|
|
|
u32 read_cr4()
|
|
{
|
|
u32 cr4;
|
|
asm("movl %%cr4, %%eax"
|
|
: "=a"(cr4));
|
|
return cr4;
|
|
}
|
|
|
|
u32 read_dr6()
|
|
{
|
|
u32 dr6;
|
|
asm("movl %%dr6, %%eax"
|
|
: "=a"(dr6));
|
|
return dr6;
|
|
}
|
|
|
|
FPUState Processor::s_clean_fpu_state;
|
|
|
|
static Vector<Processor*>* s_processors;
|
|
static SpinLock s_processor_lock;
|
|
volatile u32 Processor::g_total_processors;
|
|
static volatile bool s_smp_enabled;
|
|
|
|
Vector<Processor*>& Processor::processors()
|
|
{
|
|
ASSERT(s_processors);
|
|
return *s_processors;
|
|
}
|
|
|
|
Processor& Processor::by_id(u32 cpu)
|
|
{
|
|
// s_processors does not need to be protected by a lock of any kind.
|
|
// It is populated early in the boot process, and the BSP is waiting
|
|
// for all APs to finish, after which this array never gets modified
|
|
// again, so it's safe to not protect access to it here
|
|
auto& procs = processors();
|
|
ASSERT(procs[cpu] != nullptr);
|
|
ASSERT(procs.size() > cpu);
|
|
return *procs[cpu];
|
|
}
|
|
|
|
[[noreturn]] static inline void halt_this()
|
|
{
|
|
for (;;) {
|
|
asm volatile("cli; hlt");
|
|
}
|
|
}
|
|
|
|
void Processor::cpu_detect()
|
|
{
|
|
// NOTE: This is called during Processor::early_initialize, we cannot
|
|
// safely log at this point because we don't have kmalloc
|
|
// initialized yet!
|
|
auto set_feature =
|
|
[&](CPUFeature f) {
|
|
m_features = static_cast<CPUFeature>(static_cast<u32>(m_features) | static_cast<u32>(f));
|
|
};
|
|
m_features = static_cast<CPUFeature>(0);
|
|
|
|
CPUID processor_info(0x1);
|
|
if (processor_info.edx() & (1 << 4))
|
|
set_feature(CPUFeature::TSC);
|
|
if (processor_info.edx() & (1 << 6))
|
|
set_feature(CPUFeature::PAE);
|
|
if (processor_info.edx() & (1 << 13))
|
|
set_feature(CPUFeature::PGE);
|
|
if (processor_info.edx() & (1 << 23))
|
|
set_feature(CPUFeature::MMX);
|
|
if (processor_info.edx() & (1 << 25))
|
|
set_feature(CPUFeature::SSE);
|
|
if (processor_info.edx() & (1 << 26))
|
|
set_feature(CPUFeature::SSE2);
|
|
if (processor_info.ecx() & (1 << 0))
|
|
set_feature(CPUFeature::SSE3);
|
|
if (processor_info.ecx() & (1 << 9))
|
|
set_feature(CPUFeature::SSSE3);
|
|
if (processor_info.ecx() & (1 << 19))
|
|
set_feature(CPUFeature::SSE4_1);
|
|
if (processor_info.ecx() & (1 << 20))
|
|
set_feature(CPUFeature::SSE4_2);
|
|
if (processor_info.ecx() & (1 << 30))
|
|
set_feature(CPUFeature::RDRAND);
|
|
if (processor_info.edx() & (1 << 11)) {
|
|
u32 stepping = processor_info.eax() & 0xf;
|
|
u32 model = (processor_info.eax() >> 4) & 0xf;
|
|
u32 family = (processor_info.eax() >> 8) & 0xf;
|
|
if (!(family == 6 && model < 3 && stepping < 3))
|
|
set_feature(CPUFeature::SEP);
|
|
if ((family == 6 && model >= 3) || (family == 0xf && model >= 0xe))
|
|
set_feature(CPUFeature::CONSTANT_TSC);
|
|
}
|
|
|
|
u32 max_extended_leaf = CPUID(0x80000000).eax();
|
|
|
|
ASSERT(max_extended_leaf >= 0x80000001);
|
|
CPUID extended_processor_info(0x80000001);
|
|
if (extended_processor_info.edx() & (1 << 20))
|
|
set_feature(CPUFeature::NX);
|
|
if (extended_processor_info.edx() & (1 << 27))
|
|
set_feature(CPUFeature::RDTSCP);
|
|
if (extended_processor_info.edx() & (1 << 11)) {
|
|
// Only available in 64 bit mode
|
|
set_feature(CPUFeature::SYSCALL);
|
|
}
|
|
|
|
if (max_extended_leaf >= 0x80000007) {
|
|
CPUID cpuid(0x80000007);
|
|
if (cpuid.edx() & (1 << 8)) {
|
|
set_feature(CPUFeature::CONSTANT_TSC);
|
|
set_feature(CPUFeature::NONSTOP_TSC);
|
|
}
|
|
}
|
|
|
|
CPUID extended_features(0x7);
|
|
if (extended_features.ebx() & (1 << 20))
|
|
set_feature(CPUFeature::SMAP);
|
|
if (extended_features.ebx() & (1 << 7))
|
|
set_feature(CPUFeature::SMEP);
|
|
if (extended_features.ecx() & (1 << 2))
|
|
set_feature(CPUFeature::UMIP);
|
|
if (extended_features.ebx() & (1 << 18))
|
|
set_feature(CPUFeature::RDSEED);
|
|
}
|
|
|
|
void Processor::cpu_setup()
|
|
{
|
|
// NOTE: This is called during Processor::early_initialize, we cannot
|
|
// safely log at this point because we don't have kmalloc
|
|
// initialized yet!
|
|
cpu_detect();
|
|
|
|
if (has_feature(CPUFeature::SSE))
|
|
sse_init();
|
|
|
|
asm volatile(
|
|
"movl %%cr0, %%eax\n"
|
|
"orl $0x00010000, %%eax\n"
|
|
"movl %%eax, %%cr0\n" ::
|
|
: "%eax", "memory");
|
|
|
|
if (has_feature(CPUFeature::PGE)) {
|
|
// Turn on CR4.PGE so the CPU will respect the G bit in page tables.
|
|
asm volatile(
|
|
"mov %cr4, %eax\n"
|
|
"orl $0x80, %eax\n"
|
|
"mov %eax, %cr4\n");
|
|
}
|
|
|
|
if (has_feature(CPUFeature::NX)) {
|
|
// Turn on IA32_EFER.NXE
|
|
asm volatile(
|
|
"movl $0xc0000080, %ecx\n"
|
|
"rdmsr\n"
|
|
"orl $0x800, %eax\n"
|
|
"wrmsr\n");
|
|
}
|
|
|
|
if (has_feature(CPUFeature::SMEP)) {
|
|
// Turn on CR4.SMEP
|
|
asm volatile(
|
|
"mov %cr4, %eax\n"
|
|
"orl $0x100000, %eax\n"
|
|
"mov %eax, %cr4\n");
|
|
}
|
|
|
|
if (has_feature(CPUFeature::SMAP)) {
|
|
// Turn on CR4.SMAP
|
|
asm volatile(
|
|
"mov %cr4, %eax\n"
|
|
"orl $0x200000, %eax\n"
|
|
"mov %eax, %cr4\n");
|
|
}
|
|
|
|
if (has_feature(CPUFeature::UMIP)) {
|
|
asm volatile(
|
|
"mov %cr4, %eax\n"
|
|
"orl $0x800, %eax\n"
|
|
"mov %eax, %cr4\n");
|
|
}
|
|
|
|
if (has_feature(CPUFeature::TSC)) {
|
|
asm volatile(
|
|
"mov %cr4, %eax\n"
|
|
"orl $0x4, %eax\n"
|
|
"mov %eax, %cr4\n");
|
|
}
|
|
}
|
|
|
|
String Processor::features_string() const
|
|
{
|
|
StringBuilder builder;
|
|
auto feature_to_str =
|
|
[](CPUFeature f) -> const char*
|
|
{
|
|
switch (f) {
|
|
case CPUFeature::NX:
|
|
return "nx";
|
|
case CPUFeature::PAE:
|
|
return "pae";
|
|
case CPUFeature::PGE:
|
|
return "pge";
|
|
case CPUFeature::RDRAND:
|
|
return "rdrand";
|
|
case CPUFeature::RDSEED:
|
|
return "rdseed";
|
|
case CPUFeature::SMAP:
|
|
return "smap";
|
|
case CPUFeature::SMEP:
|
|
return "smep";
|
|
case CPUFeature::SSE:
|
|
return "sse";
|
|
case CPUFeature::TSC:
|
|
return "tsc";
|
|
case CPUFeature::RDTSCP:
|
|
return "rdtscp";
|
|
case CPUFeature::CONSTANT_TSC:
|
|
return "constant_tsc";
|
|
case CPUFeature::NONSTOP_TSC:
|
|
return "nonstop_tsc";
|
|
case CPUFeature::UMIP:
|
|
return "umip";
|
|
case CPUFeature::SEP:
|
|
return "sep";
|
|
case CPUFeature::SYSCALL:
|
|
return "syscall";
|
|
case CPUFeature::MMX:
|
|
return "mmx";
|
|
case CPUFeature::SSE2:
|
|
return "sse2";
|
|
case CPUFeature::SSE3:
|
|
return "sse3";
|
|
case CPUFeature::SSSE3:
|
|
return "ssse3";
|
|
case CPUFeature::SSE4_1:
|
|
return "sse4.1";
|
|
case CPUFeature::SSE4_2:
|
|
return "sse4.2";
|
|
// no default statement here intentionally so that we get
|
|
// a warning if a new feature is forgotten to be added here
|
|
}
|
|
// Shouldn't ever happen
|
|
return "???";
|
|
};
|
|
bool first = true;
|
|
for (u32 flag = 1; flag != 0; flag <<= 1) {
|
|
if ((static_cast<u32>(m_features) & flag) != 0) {
|
|
if (first)
|
|
first = false;
|
|
else
|
|
builder.append(' ');
|
|
auto str = feature_to_str(static_cast<CPUFeature>(flag));
|
|
builder.append(str, strlen(str));
|
|
}
|
|
}
|
|
return builder.build();
|
|
}
|
|
|
|
void Processor::early_initialize(u32 cpu)
|
|
{
|
|
m_self = this;
|
|
|
|
m_cpu = cpu;
|
|
m_in_irq = 0;
|
|
m_in_critical = 0;
|
|
|
|
m_invoke_scheduler_async = false;
|
|
m_scheduler_initialized = false;
|
|
|
|
m_message_queue = nullptr;
|
|
m_idle_thread = nullptr;
|
|
m_current_thread = nullptr;
|
|
m_scheduler_data = nullptr;
|
|
m_mm_data = nullptr;
|
|
m_info = nullptr;
|
|
|
|
m_halt_requested = false;
|
|
if (cpu == 0) {
|
|
s_smp_enabled = false;
|
|
atomic_store(&g_total_processors, 1u, AK::MemoryOrder::memory_order_release);
|
|
} else {
|
|
atomic_fetch_add(&g_total_processors, 1u, AK::MemoryOrder::memory_order_acq_rel);
|
|
}
|
|
|
|
deferred_call_pool_init();
|
|
|
|
cpu_setup();
|
|
gdt_init();
|
|
ASSERT(¤t() == this); // sanity check
|
|
}
|
|
|
|
void Processor::initialize(u32 cpu)
|
|
{
|
|
ASSERT(m_self == this);
|
|
ASSERT(¤t() == this); // sanity check
|
|
|
|
klog() << "CPU[" << id() << "]: Supported features: " << features_string();
|
|
if (!has_feature(CPUFeature::RDRAND))
|
|
klog() << "CPU[" << id() << "]: No RDRAND support detected, randomness will be poor";
|
|
|
|
if (cpu == 0)
|
|
idt_init();
|
|
else
|
|
flush_idt();
|
|
|
|
if (cpu == 0) {
|
|
ASSERT((FlatPtr(&s_clean_fpu_state) & 0xF) == 0);
|
|
asm volatile("fninit");
|
|
asm volatile("fxsave %0"
|
|
: "=m"(s_clean_fpu_state));
|
|
}
|
|
|
|
m_info = new ProcessorInfo(*this);
|
|
|
|
{
|
|
ScopedSpinLock lock(s_processor_lock);
|
|
// We need to prevent races between APs starting up at the same time
|
|
if (!s_processors)
|
|
s_processors = new Vector<Processor*>();
|
|
if (cpu >= s_processors->size())
|
|
s_processors->resize(cpu + 1);
|
|
(*s_processors)[cpu] = this;
|
|
}
|
|
}
|
|
|
|
void Processor::write_raw_gdt_entry(u16 selector, u32 low, u32 high)
|
|
{
|
|
u16 i = (selector & 0xfffc) >> 3;
|
|
u32 prev_gdt_length = m_gdt_length;
|
|
|
|
if (i > m_gdt_length) {
|
|
m_gdt_length = i + 1;
|
|
ASSERT(m_gdt_length <= sizeof(m_gdt) / sizeof(m_gdt[0]));
|
|
m_gdtr.limit = (m_gdt_length + 1) * 8 - 1;
|
|
}
|
|
m_gdt[i].low = low;
|
|
m_gdt[i].high = high;
|
|
|
|
// clear selectors we may have skipped
|
|
while (i < prev_gdt_length) {
|
|
m_gdt[i].low = 0;
|
|
m_gdt[i].high = 0;
|
|
i++;
|
|
}
|
|
}
|
|
|
|
void Processor::write_gdt_entry(u16 selector, Descriptor& descriptor)
|
|
{
|
|
write_raw_gdt_entry(selector, descriptor.low, descriptor.high);
|
|
}
|
|
|
|
Descriptor& Processor::get_gdt_entry(u16 selector)
|
|
{
|
|
u16 i = (selector & 0xfffc) >> 3;
|
|
return *(Descriptor*)(&m_gdt[i]);
|
|
}
|
|
|
|
void Processor::flush_gdt()
|
|
{
|
|
m_gdtr.address = m_gdt;
|
|
m_gdtr.limit = (m_gdt_length * 8) - 1;
|
|
asm volatile("lgdt %0" ::"m"(m_gdtr)
|
|
: "memory");
|
|
}
|
|
|
|
const DescriptorTablePointer& Processor::get_gdtr()
|
|
{
|
|
return m_gdtr;
|
|
}
|
|
|
|
bool Processor::get_context_frame_ptr(Thread& thread, u32& frame_ptr, u32& eip)
|
|
{
|
|
ScopedCritical critical;
|
|
auto& proc = Processor::current();
|
|
if (&thread == proc.current_thread()) {
|
|
ASSERT(thread.state() == Thread::Running);
|
|
asm volatile("movl %%ebp, %%eax"
|
|
: "=g"(frame_ptr));
|
|
} else {
|
|
// Since the thread may be running on another processor, there
|
|
// is a chance a context switch may happen while we're trying
|
|
// to get it. It also won't be entirely accurate and merely
|
|
// reflect the status at the last context switch.
|
|
ScopedSpinLock lock(g_scheduler_lock);
|
|
if (thread.state() == Thread::Running) {
|
|
ASSERT(thread.cpu() != proc.id());
|
|
// TODO: If this is the case, the thread is currently running
|
|
// on another processor. We can't trust the kernel stack as
|
|
// it may be changing at any time. We need to probably send
|
|
// an IPI to that processor, have it walk the stack and wait
|
|
// until it returns the data back to us
|
|
dbg() << "CPU[" << proc.id() << "] getting stack for "
|
|
<< thread << " on other CPU# " << thread.cpu() << " not yet implemented!";
|
|
frame_ptr = eip = 0; // TODO
|
|
return false;
|
|
} else {
|
|
// We need to retrieve ebp from what was last pushed to the kernel
|
|
// stack. Before switching out of that thread, it switch_context
|
|
// pushed the callee-saved registers, and the last of them happens
|
|
// to be ebp.
|
|
auto& tss = thread.tss();
|
|
u32* stack_top = reinterpret_cast<u32*>(tss.esp);
|
|
frame_ptr = stack_top[0];
|
|
eip = tss.eip;
|
|
}
|
|
}
|
|
return true;
|
|
}
|
|
|
|
extern "C" void enter_thread_context(Thread* from_thread, Thread* to_thread)
|
|
{
|
|
ASSERT(from_thread == to_thread || from_thread->state() != Thread::Running);
|
|
ASSERT(to_thread->state() == Thread::Running);
|
|
|
|
auto& processor = Processor::current();
|
|
processor.set_current_thread(*to_thread);
|
|
|
|
auto& from_tss = from_thread->tss();
|
|
auto& to_tss = to_thread->tss();
|
|
asm volatile("fxsave %0"
|
|
: "=m"(from_thread->fpu_state()));
|
|
|
|
from_tss.fs = get_fs();
|
|
from_tss.gs = get_gs();
|
|
set_fs(to_tss.fs);
|
|
set_gs(to_tss.gs);
|
|
|
|
auto& tls_descriptor = processor.get_gdt_entry(GDT_SELECTOR_TLS);
|
|
tls_descriptor.set_base(to_thread->thread_specific_data().as_ptr());
|
|
tls_descriptor.set_limit(to_thread->thread_specific_region_size());
|
|
|
|
if (from_tss.cr3 != to_tss.cr3)
|
|
write_cr3(to_tss.cr3);
|
|
|
|
to_thread->set_cpu(processor.id());
|
|
|
|
asm volatile("fxrstor %0"
|
|
::"m"(to_thread->fpu_state()));
|
|
|
|
// TODO: debug registers
|
|
// TODO: ioperm?
|
|
}
|
|
|
|
#define ENTER_THREAD_CONTEXT_ARGS_SIZE (2 * 4) // to_thread, from_thread
|
|
|
|
void Processor::switch_context(Thread*& from_thread, Thread*& to_thread)
|
|
{
|
|
ASSERT(!in_irq());
|
|
ASSERT(m_in_critical == 1);
|
|
ASSERT(is_kernel_mode());
|
|
#ifdef CONTEXT_SWITCH_DEBUG
|
|
dbg() << "switch_context --> switching out of: " << VirtualAddress(from_thread) << " " << *from_thread;
|
|
#endif
|
|
|
|
// Switch to new thread context, passing from_thread and to_thread
|
|
// through to the new context using registers edx and eax
|
|
asm volatile(
|
|
// NOTE: changing how much we push to the stack affects
|
|
// SWITCH_CONTEXT_TO_STACK_SIZE and thread_context_first_enter()!
|
|
"pushfl \n"
|
|
"pushl %%ebx \n"
|
|
"pushl %%esi \n"
|
|
"pushl %%edi \n"
|
|
"pushl %%ebp \n"
|
|
"movl %%esp, %[from_esp] \n"
|
|
"movl $1f, %[from_eip] \n"
|
|
"movl %[to_esp0], %%ebx \n"
|
|
"movl %%ebx, %[tss_esp0] \n"
|
|
"movl %[to_esp], %%esp \n"
|
|
"pushl %[to_thread] \n"
|
|
"pushl %[from_thread] \n"
|
|
"pushl %[to_eip] \n"
|
|
"cld \n"
|
|
"jmp enter_thread_context \n"
|
|
"1: \n"
|
|
"popl %%edx \n"
|
|
"popl %%eax \n"
|
|
"popl %%ebp \n"
|
|
"popl %%edi \n"
|
|
"popl %%esi \n"
|
|
"popl %%ebx \n"
|
|
"popfl \n"
|
|
: [from_esp] "=m" (from_thread->tss().esp),
|
|
[from_eip] "=m" (from_thread->tss().eip),
|
|
[tss_esp0] "=m" (m_tss.esp0),
|
|
"=d" (from_thread), // needed so that from_thread retains the correct value
|
|
"=a" (to_thread) // needed so that to_thread retains the correct value
|
|
: [to_esp] "g" (to_thread->tss().esp),
|
|
[to_esp0] "g" (to_thread->tss().esp0),
|
|
[to_eip] "c" (to_thread->tss().eip),
|
|
[from_thread] "d" (from_thread),
|
|
[to_thread] "a" (to_thread)
|
|
);
|
|
#ifdef CONTEXT_SWITCH_DEBUG
|
|
dbg() << "switch_context <-- from " << VirtualAddress(from_thread) << " " << *from_thread << " to " << VirtualAddress(to_thread) << " " << *to_thread;
|
|
#endif
|
|
}
|
|
|
|
extern "C" void context_first_init(Thread* from_thread, Thread* to_thread, TrapFrame* trap)
|
|
{
|
|
ASSERT(!are_interrupts_enabled());
|
|
ASSERT(is_kernel_mode());
|
|
(void)from_thread;
|
|
(void)to_thread;
|
|
(void)trap;
|
|
|
|
#ifdef CONTEXT_SWITCH_DEBUG
|
|
dbg() << "switch_context <-- from " << VirtualAddress(from_thread) << " " << *from_thread << " to " << VirtualAddress(to_thread) << " " << *to_thread << " (context_first_init)";
|
|
#endif
|
|
|
|
ASSERT(to_thread == Thread::current());
|
|
|
|
Scheduler::enter_current(*from_thread);
|
|
|
|
// Since we got here and don't have Scheduler::context_switch in the
|
|
// call stack (because this is the first time we switched into this
|
|
// context), we need to notify the scheduler so that it can release
|
|
// the scheduler lock.
|
|
Scheduler::leave_on_first_switch(trap->regs->eflags);
|
|
}
|
|
|
|
extern "C" void thread_context_first_enter(void);
|
|
asm(
|
|
// enter_thread_context returns to here first time a thread is executing
|
|
".globl thread_context_first_enter \n"
|
|
"thread_context_first_enter: \n"
|
|
// switch_context will have pushed from_thread and to_thread to our new
|
|
// stack prior to thread_context_first_enter() being called, and the
|
|
// pointer to TrapFrame was the top of the stack before that
|
|
" movl 8(%esp), %ebx \n" // save pointer to TrapFrame
|
|
" cld \n"
|
|
" call context_first_init \n"
|
|
" addl $" __STRINGIFY(ENTER_THREAD_CONTEXT_ARGS_SIZE) ", %esp \n"
|
|
" movl %ebx, 0(%esp) \n" // push pointer to TrapFrame
|
|
" jmp common_trap_exit \n"
|
|
);
|
|
|
|
u32 Processor::init_context(Thread& thread, bool leave_crit)
|
|
{
|
|
ASSERT(is_kernel_mode());
|
|
ASSERT(g_scheduler_lock.is_locked());
|
|
if (leave_crit) {
|
|
// Leave the critical section we set up in in Process::exec,
|
|
// but because we still have the scheduler lock we should end up with 1
|
|
m_in_critical--; // leave it without triggering anything or restoring flags
|
|
ASSERT(in_critical() == 1);
|
|
}
|
|
|
|
const u32 kernel_stack_top = thread.kernel_stack_top();
|
|
u32 stack_top = kernel_stack_top;
|
|
|
|
// TODO: handle NT?
|
|
ASSERT((cpu_flags() & 0x24000) == 0); // Assume !(NT | VM)
|
|
|
|
auto& tss = thread.tss();
|
|
bool return_to_user = (tss.cs & 3) != 0;
|
|
|
|
// make room for an interrupt frame
|
|
if (!return_to_user) {
|
|
// userspace_esp and userspace_ss are not popped off by iret
|
|
// unless we're switching back to user mode
|
|
stack_top -= sizeof(RegisterState) - 2 * sizeof(u32);
|
|
} else {
|
|
stack_top -= sizeof(RegisterState);
|
|
}
|
|
|
|
// we want to end up 16-byte aligned, %esp + 4 should be aligned
|
|
stack_top -= sizeof(u32);
|
|
*reinterpret_cast<u32*>(kernel_stack_top - 4) = 0;
|
|
|
|
// set up the stack so that after returning from thread_context_first_enter()
|
|
// we will end up either in kernel mode or user mode, depending on how the thread is set up
|
|
// However, the first step is to always start in kernel mode with thread_context_first_enter
|
|
RegisterState& iretframe = *reinterpret_cast<RegisterState*>(stack_top);
|
|
iretframe.ss = tss.ss;
|
|
iretframe.gs = tss.gs;
|
|
iretframe.fs = tss.fs;
|
|
iretframe.es = tss.es;
|
|
iretframe.ds = tss.ds;
|
|
iretframe.edi = tss.edi;
|
|
iretframe.esi = tss.esi;
|
|
iretframe.ebp = tss.ebp;
|
|
iretframe.esp = 0;
|
|
iretframe.ebx = tss.ebx;
|
|
iretframe.edx = tss.edx;
|
|
iretframe.ecx = tss.ecx;
|
|
iretframe.eax = tss.eax;
|
|
iretframe.eflags = tss.eflags;
|
|
iretframe.eip = tss.eip;
|
|
iretframe.cs = tss.cs;
|
|
if (return_to_user) {
|
|
iretframe.userspace_esp = tss.esp;
|
|
iretframe.userspace_ss = tss.ss;
|
|
}
|
|
|
|
// make space for a trap frame
|
|
stack_top -= sizeof(TrapFrame);
|
|
TrapFrame& trap = *reinterpret_cast<TrapFrame*>(stack_top);
|
|
trap.regs = &iretframe;
|
|
trap.prev_irq_level = 0;
|
|
|
|
stack_top -= sizeof(u32); // pointer to TrapFrame
|
|
*reinterpret_cast<u32*>(stack_top) = stack_top + 4;
|
|
|
|
#ifdef CONTEXT_SWITCH_DEBUG
|
|
if (return_to_user)
|
|
dbg() << "init_context " << thread << " (" << VirtualAddress(&thread) << ") set up to execute at eip: " << String::format("%02x:%08x", iretframe.cs, (u32)tss.eip) << " esp: " << VirtualAddress(tss.esp) << " stack top: " << VirtualAddress(stack_top) << " user esp: " << String::format("%02x:%08x", iretframe.userspace_ss, (u32)iretframe.userspace_esp);
|
|
else
|
|
dbg() << "init_context " << thread << " (" << VirtualAddress(&thread) << ") set up to execute at eip: " << String::format("%02x:%08x", iretframe.cs, (u32)tss.eip) << " esp: " << VirtualAddress(tss.esp) << " stack top: " << VirtualAddress(stack_top);
|
|
#endif
|
|
|
|
// make switch_context() always first return to thread_context_first_enter()
|
|
// in kernel mode, so set up these values so that we end up popping iretframe
|
|
// off the stack right after the context switch completed, at which point
|
|
// control is transferred to what iretframe is pointing to.
|
|
tss.eip = FlatPtr(&thread_context_first_enter);
|
|
tss.esp0 = kernel_stack_top;
|
|
tss.esp = stack_top;
|
|
tss.cs = GDT_SELECTOR_CODE0;
|
|
tss.ds = GDT_SELECTOR_DATA0;
|
|
tss.es = GDT_SELECTOR_DATA0;
|
|
tss.gs = GDT_SELECTOR_DATA0;
|
|
tss.ss = GDT_SELECTOR_DATA0;
|
|
tss.fs = GDT_SELECTOR_PROC;
|
|
return stack_top;
|
|
}
|
|
|
|
extern "C" u32 do_init_context(Thread* thread, u32 flags)
|
|
{
|
|
ASSERT_INTERRUPTS_DISABLED();
|
|
thread->tss().eflags = flags;
|
|
return Processor::current().init_context(*thread, true);
|
|
}
|
|
|
|
extern "C" void do_assume_context(Thread* thread, u32 flags);
|
|
|
|
asm(
|
|
".global do_assume_context \n"
|
|
"do_assume_context: \n"
|
|
" movl 4(%esp), %ebx \n"
|
|
" movl 8(%esp), %esi \n"
|
|
// We're going to call Processor::init_context, so just make sure
|
|
// we have enough stack space so we don't stomp over it
|
|
" subl $(" __STRINGIFY(4 + REGISTER_STATE_SIZE + TRAP_FRAME_SIZE + 4) "), %esp \n"
|
|
" pushl %esi \n"
|
|
" pushl %ebx \n"
|
|
" cld \n"
|
|
" call do_init_context \n"
|
|
" addl $8, %esp \n"
|
|
" movl %eax, %esp \n" // move stack pointer to what Processor::init_context set up for us
|
|
" pushl %ebx \n" // push to_thread
|
|
" pushl %ebx \n" // push from_thread
|
|
" pushl $thread_context_first_enter \n" // should be same as tss.eip
|
|
" jmp enter_thread_context \n"
|
|
);
|
|
|
|
void Processor::assume_context(Thread& thread, u32 flags)
|
|
{
|
|
#ifdef CONTEXT_SWITCH_DEBUG
|
|
dbg() << "Assume context for thread " << VirtualAddress(&thread) << " " << thread;
|
|
#endif
|
|
ASSERT_INTERRUPTS_DISABLED();
|
|
Scheduler::prepare_after_exec();
|
|
// in_critical() should be 2 here. The critical section in Process::exec
|
|
// and then the scheduler lock
|
|
ASSERT(Processor::current().in_critical() == 2);
|
|
do_assume_context(&thread, flags);
|
|
ASSERT_NOT_REACHED();
|
|
}
|
|
|
|
extern "C" void pre_init_finished(void)
|
|
{
|
|
ASSERT(g_scheduler_lock.own_lock());
|
|
|
|
// Because init_finished() will wait on the other APs, we need
|
|
// to release the scheduler lock so that the other APs can also get
|
|
// to this point
|
|
|
|
// The target flags will get restored upon leaving the trap
|
|
u32 prev_flags = cpu_flags();
|
|
Scheduler::leave_on_first_switch(prev_flags);
|
|
}
|
|
|
|
extern "C" void post_init_finished(void)
|
|
{
|
|
// We need to re-acquire the scheduler lock before a context switch
|
|
// transfers control into the idle loop, which needs the lock held
|
|
Scheduler::prepare_for_idle_loop();
|
|
}
|
|
|
|
void Processor::initialize_context_switching(Thread& initial_thread)
|
|
{
|
|
ASSERT(initial_thread.process().is_kernel_process());
|
|
|
|
auto& tss = initial_thread.tss();
|
|
m_tss = tss;
|
|
m_tss.esp0 = tss.esp0;
|
|
m_tss.ss0 = GDT_SELECTOR_DATA0;
|
|
// user mode needs to be able to switch to kernel mode:
|
|
m_tss.cs = m_tss.ds = m_tss.es = m_tss.gs = m_tss.ss = GDT_SELECTOR_CODE0 | 3;
|
|
m_tss.fs = GDT_SELECTOR_PROC | 3;
|
|
|
|
m_scheduler_initialized = true;
|
|
|
|
asm volatile(
|
|
"movl %[new_esp], %%esp \n" // switch to new stack
|
|
"pushl %[from_to_thread] \n" // to_thread
|
|
"pushl %[from_to_thread] \n" // from_thread
|
|
"pushl $" __STRINGIFY(GDT_SELECTOR_CODE0) " \n"
|
|
"pushl %[new_eip] \n" // save the entry eip to the stack
|
|
"movl %%esp, %%ebx \n"
|
|
"addl $20, %%ebx \n" // calculate pointer to TrapFrame
|
|
"pushl %%ebx \n"
|
|
"cld \n"
|
|
"pushl %[cpu] \n" // push argument for init_finished before register is clobbered
|
|
"call pre_init_finished \n"
|
|
"call init_finished \n"
|
|
"addl $4, %%esp \n"
|
|
"call post_init_finished \n"
|
|
"call enter_trap_no_irq \n"
|
|
"addl $4, %%esp \n"
|
|
"lret \n"
|
|
:: [new_esp] "g" (tss.esp),
|
|
[new_eip] "a" (tss.eip),
|
|
[from_to_thread] "b" (&initial_thread),
|
|
[cpu] "c" (id())
|
|
);
|
|
|
|
ASSERT_NOT_REACHED();
|
|
}
|
|
|
|
void Processor::enter_trap(TrapFrame& trap, bool raise_irq)
|
|
{
|
|
InterruptDisabler disabler;
|
|
trap.prev_irq_level = m_in_irq;
|
|
if (raise_irq)
|
|
m_in_irq++;
|
|
}
|
|
|
|
void Processor::exit_trap(TrapFrame& trap)
|
|
{
|
|
InterruptDisabler disabler;
|
|
ASSERT(m_in_irq >= trap.prev_irq_level);
|
|
m_in_irq = trap.prev_irq_level;
|
|
|
|
smp_process_pending_messages();
|
|
|
|
if (!m_in_irq && !m_in_critical)
|
|
check_invoke_scheduler();
|
|
}
|
|
|
|
void Processor::check_invoke_scheduler()
|
|
{
|
|
ASSERT(!m_in_irq);
|
|
ASSERT(!m_in_critical);
|
|
if (m_invoke_scheduler_async && m_scheduler_initialized) {
|
|
m_invoke_scheduler_async = false;
|
|
Scheduler::invoke_async();
|
|
}
|
|
}
|
|
|
|
void Processor::flush_tlb_local(VirtualAddress vaddr, size_t page_count)
|
|
{
|
|
auto ptr = vaddr.as_ptr();
|
|
while (page_count > 0) {
|
|
asm volatile("invlpg %0"
|
|
:
|
|
: "m"(*ptr)
|
|
: "memory");
|
|
ptr += PAGE_SIZE;
|
|
page_count--;
|
|
}
|
|
}
|
|
|
|
void Processor::flush_tlb(VirtualAddress vaddr, size_t page_count)
|
|
{
|
|
flush_tlb_local(vaddr, page_count);
|
|
if (s_smp_enabled)
|
|
smp_broadcast_flush_tlb(vaddr, page_count);
|
|
}
|
|
|
|
static volatile ProcessorMessage* s_message_pool;
|
|
|
|
void Processor::smp_return_to_pool(ProcessorMessage& msg)
|
|
{
|
|
ProcessorMessage* next = nullptr;
|
|
do {
|
|
msg.next = next;
|
|
} while (!atomic_compare_exchange_strong(&s_message_pool, next, &msg, AK::MemoryOrder::memory_order_acq_rel));
|
|
}
|
|
|
|
ProcessorMessage& Processor::smp_get_from_pool()
|
|
{
|
|
ProcessorMessage* msg;
|
|
|
|
// The assumption is that messages are never removed from the pool!
|
|
for (;;) {
|
|
msg = atomic_load(&s_message_pool, AK::MemoryOrder::memory_order_consume);
|
|
if (!msg) {
|
|
if (!Processor::current().smp_process_pending_messages()) {
|
|
// TODO: pause for a bit?
|
|
}
|
|
continue;
|
|
}
|
|
// If another processor were to use this message in the meanwhile,
|
|
// "msg" is still valid (because it never gets freed). We'd detect
|
|
// this because the expected value "msg" and pool would
|
|
// no longer match, and the compare_exchange will fail. But accessing
|
|
// "msg->next" is always safe here.
|
|
if (atomic_compare_exchange_strong(&s_message_pool, msg, msg->next, AK::MemoryOrder::memory_order_acq_rel)) {
|
|
// We successfully "popped" this available message
|
|
break;
|
|
}
|
|
}
|
|
|
|
ASSERT(msg != nullptr);
|
|
return *msg;
|
|
}
|
|
|
|
void Processor::smp_enable()
|
|
{
|
|
size_t msg_pool_size = Processor::count() * 100u;
|
|
size_t msg_entries_cnt = Processor::count();
|
|
|
|
auto msgs = new ProcessorMessage[msg_pool_size];
|
|
auto msg_entries = new ProcessorMessageEntry[msg_pool_size * msg_entries_cnt];
|
|
size_t msg_entry_i = 0;
|
|
for (size_t i = 0; i < msg_pool_size; i++, msg_entry_i += msg_entries_cnt) {
|
|
auto& msg = msgs[i];
|
|
msg.next = i < msg_pool_size - 1 ? &msgs[i + 1] : nullptr;
|
|
msg.per_proc_entries = &msg_entries[msg_entry_i];
|
|
for (size_t k = 0; k < msg_entries_cnt; k++)
|
|
msg_entries[msg_entry_i + k].msg = &msg;
|
|
}
|
|
|
|
atomic_store(&s_message_pool, &msgs[0], AK::MemoryOrder::memory_order_release);
|
|
|
|
// Start sending IPI messages
|
|
s_smp_enabled = true;
|
|
}
|
|
|
|
void Processor::smp_cleanup_message(ProcessorMessage& msg)
|
|
{
|
|
switch (msg.type) {
|
|
case ProcessorMessage::CallbackWithData:
|
|
if (msg.callback_with_data.free)
|
|
msg.callback_with_data.free(msg.callback_with_data.data);
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
|
|
bool Processor::smp_process_pending_messages()
|
|
{
|
|
bool did_process = false;
|
|
u32 prev_flags;
|
|
enter_critical(prev_flags);
|
|
|
|
if (auto pending_msgs = atomic_exchange(&m_message_queue, nullptr, AK::MemoryOrder::memory_order_acq_rel)) {
|
|
// We pulled the stack of pending messages in LIFO order, so we need to reverse the list first
|
|
auto reverse_list =
|
|
[](ProcessorMessageEntry* list) -> ProcessorMessageEntry*
|
|
{
|
|
ProcessorMessageEntry* rev_list = nullptr;
|
|
while (list) {
|
|
auto next = list->next;
|
|
list->next = rev_list;
|
|
rev_list = list;
|
|
list = next;
|
|
}
|
|
return rev_list;
|
|
};
|
|
|
|
pending_msgs = reverse_list(pending_msgs);
|
|
|
|
// now process in the right order
|
|
ProcessorMessageEntry* next_msg;
|
|
for (auto cur_msg = pending_msgs; cur_msg; cur_msg = next_msg) {
|
|
next_msg = cur_msg->next;
|
|
auto msg = cur_msg->msg;
|
|
|
|
#ifdef SMP_DEBUG
|
|
dbg() << "SMP[" << id() << "]: Processing message " << VirtualAddress(msg);
|
|
#endif
|
|
|
|
switch (msg->type) {
|
|
case ProcessorMessage::Callback:
|
|
msg->callback.handler();
|
|
break;
|
|
case ProcessorMessage::CallbackWithData:
|
|
msg->callback_with_data.handler(msg->callback_with_data.data);
|
|
break;
|
|
case ProcessorMessage::FlushTlb:
|
|
flush_tlb_local(VirtualAddress(msg->flush_tlb.ptr), msg->flush_tlb.page_count);
|
|
break;
|
|
}
|
|
|
|
bool is_async = msg->async; // Need to cache this value *before* dropping the ref count!
|
|
auto prev_refs = atomic_fetch_sub(&msg->refs, 1u, AK::MemoryOrder::memory_order_acq_rel);
|
|
ASSERT(prev_refs != 0);
|
|
if (prev_refs == 1) {
|
|
// All processors handled this. If this is an async message,
|
|
// we need to clean it up and return it to the pool
|
|
if (is_async) {
|
|
smp_cleanup_message(*msg);
|
|
smp_return_to_pool(*msg);
|
|
}
|
|
}
|
|
|
|
if (m_halt_requested.load(AK::MemoryOrder::memory_order_relaxed))
|
|
halt_this();
|
|
}
|
|
did_process = true;
|
|
} else if (m_halt_requested.load(AK::MemoryOrder::memory_order_relaxed)) {
|
|
halt_this();
|
|
}
|
|
|
|
leave_critical(prev_flags);
|
|
return did_process;
|
|
}
|
|
|
|
bool Processor::smp_queue_message(ProcessorMessage& msg)
|
|
{
|
|
// Note that it's quite possible that the other processor may pop
|
|
// the queue at any given time. We rely on the fact that the messages
|
|
// are pooled and never get freed!
|
|
auto& msg_entry = msg.per_proc_entries[id()];
|
|
ASSERT(msg_entry.msg == &msg);
|
|
ProcessorMessageEntry* next = nullptr;
|
|
do {
|
|
msg_entry.next = next;
|
|
} while (!atomic_compare_exchange_strong(&m_message_queue, next, &msg_entry, AK::MemoryOrder::memory_order_acq_rel));
|
|
return next == nullptr;
|
|
}
|
|
|
|
void Processor::smp_broadcast_message(ProcessorMessage& msg, bool async)
|
|
{
|
|
auto& cur_proc = Processor::current();
|
|
msg.async = async;
|
|
#ifdef SMP_DEBUG
|
|
dbg() << "SMP[" << cur_proc.id() << "]: Broadcast message " << VirtualAddress(&msg) << " to cpus: " << (count()) << " proc: " << VirtualAddress(&cur_proc);
|
|
#endif
|
|
atomic_store(&msg.refs, count() - 1, AK::MemoryOrder::memory_order_release);
|
|
ASSERT(msg.refs > 0);
|
|
for_each(
|
|
[&](Processor& proc) -> IterationDecision {
|
|
if (&proc != &cur_proc) {
|
|
if (proc.smp_queue_message(msg)) {
|
|
// TODO: only send IPI to that CPU if we queued the first
|
|
}
|
|
}
|
|
return IterationDecision::Continue;
|
|
});
|
|
|
|
// Now trigger an IPI on all other APs
|
|
APIC::the().broadcast_ipi();
|
|
|
|
if (!async) {
|
|
// If synchronous then we must cleanup and return the message back
|
|
// to the pool. Otherwise, the last processor to complete it will return it
|
|
while (atomic_load(&msg.refs, AK::MemoryOrder::memory_order_consume) != 0) {
|
|
// TODO: pause for a bit?
|
|
|
|
// We need to check here if another processor may have requested
|
|
// us to halt before this message could be delivered. Otherwise
|
|
// we're just spinning the CPU because msg.refs will never drop to 0.
|
|
if (cur_proc.m_halt_requested.load(AK::MemoryOrder::memory_order_relaxed))
|
|
halt_this();
|
|
}
|
|
|
|
smp_cleanup_message(msg);
|
|
smp_return_to_pool(msg);
|
|
}
|
|
}
|
|
|
|
void Processor::smp_broadcast(void (*callback)(void*), void* data, void (*free_data)(void*), bool async)
|
|
{
|
|
auto& msg = smp_get_from_pool();
|
|
msg.type = ProcessorMessage::CallbackWithData;
|
|
msg.callback_with_data.handler = callback;
|
|
msg.callback_with_data.data = data;
|
|
msg.callback_with_data.free = free_data;
|
|
smp_broadcast_message(msg, async);
|
|
}
|
|
|
|
void Processor::smp_broadcast(void (*callback)(), bool async)
|
|
{
|
|
auto& msg = smp_get_from_pool();
|
|
msg.type = ProcessorMessage::CallbackWithData;
|
|
msg.callback.handler = callback;
|
|
smp_broadcast_message(msg, async);
|
|
}
|
|
|
|
void Processor::smp_broadcast_flush_tlb(VirtualAddress vaddr, size_t page_count)
|
|
{
|
|
auto& msg = smp_get_from_pool();
|
|
msg.type = ProcessorMessage::FlushTlb;
|
|
msg.flush_tlb.ptr = vaddr.as_ptr();
|
|
msg.flush_tlb.page_count = page_count;
|
|
smp_broadcast_message(msg, false);
|
|
}
|
|
|
|
void Processor::smp_broadcast_halt()
|
|
{
|
|
// We don't want to use a message, because this could have been triggered
|
|
// by being out of memory and we might not be able to get a message
|
|
for_each(
|
|
[&](Processor& proc) -> IterationDecision {
|
|
proc.m_halt_requested.store(true, AK::MemoryOrder::memory_order_release);
|
|
return IterationDecision::Continue;
|
|
});
|
|
|
|
// Now trigger an IPI on all other APs
|
|
APIC::the().broadcast_ipi();
|
|
}
|
|
|
|
void Processor::Processor::halt()
|
|
{
|
|
if (s_smp_enabled)
|
|
smp_broadcast_halt();
|
|
|
|
halt_this();
|
|
}
|
|
|
|
void Processor::deferred_call_pool_init()
|
|
{
|
|
size_t pool_count = sizeof(m_deferred_call_pool) / sizeof(m_deferred_call_pool[0]);
|
|
for (size_t i = 0; i < pool_count; i++) {
|
|
auto& entry = m_deferred_call_pool[i];
|
|
entry.next = i < pool_count - 1 ? &m_deferred_call_pool[i + 1] : nullptr;
|
|
entry.was_allocated = false;
|
|
}
|
|
m_pending_deferred_calls = nullptr;
|
|
m_free_deferred_call_pool_entry = &m_deferred_call_pool[0];
|
|
}
|
|
|
|
void Processor::deferred_call_return_to_pool(DeferredCallEntry* entry)
|
|
{
|
|
ASSERT(m_in_critical);
|
|
ASSERT(!entry->was_allocated);
|
|
|
|
entry->next = m_free_deferred_call_pool_entry;
|
|
m_free_deferred_call_pool_entry = entry;
|
|
}
|
|
|
|
DeferredCallEntry* Processor::deferred_call_get_free()
|
|
{
|
|
ASSERT(m_in_critical);
|
|
|
|
if (m_free_deferred_call_pool_entry) {
|
|
// Fast path, we have an entry in our pool
|
|
auto* entry = m_free_deferred_call_pool_entry;
|
|
m_free_deferred_call_pool_entry = entry->next;
|
|
ASSERT(!entry->was_allocated);
|
|
return entry;
|
|
}
|
|
|
|
auto* entry = new DeferredCallEntry;
|
|
entry->was_allocated = true;
|
|
return entry;
|
|
}
|
|
|
|
void Processor::deferred_call_execute_pending()
|
|
{
|
|
ASSERT(m_in_critical);
|
|
|
|
if (!m_pending_deferred_calls)
|
|
return;
|
|
auto* pending_list = m_pending_deferred_calls;
|
|
m_pending_deferred_calls = nullptr;
|
|
|
|
// We pulled the stack of pending deferred calls in LIFO order, so we need to reverse the list first
|
|
auto reverse_list =
|
|
[](DeferredCallEntry* list) -> DeferredCallEntry*
|
|
{
|
|
DeferredCallEntry* rev_list = nullptr;
|
|
while (list) {
|
|
auto next = list->next;
|
|
list->next = rev_list;
|
|
rev_list = list;
|
|
list = next;
|
|
}
|
|
return rev_list;
|
|
};
|
|
pending_list = reverse_list(pending_list);
|
|
|
|
do {
|
|
// Call the appropriate callback handler
|
|
if (pending_list->have_data) {
|
|
pending_list->callback_with_data.handler(pending_list->callback_with_data.data);
|
|
if (pending_list->callback_with_data.free)
|
|
pending_list->callback_with_data.free(pending_list->callback_with_data.data);
|
|
} else {
|
|
pending_list->callback.handler();
|
|
}
|
|
|
|
// Return the entry back to the pool, or free it
|
|
auto* next = pending_list->next;
|
|
if (pending_list->was_allocated)
|
|
delete pending_list;
|
|
else
|
|
deferred_call_return_to_pool(pending_list);
|
|
pending_list = next;
|
|
} while (pending_list);
|
|
}
|
|
|
|
void Processor::deferred_call_queue_entry(DeferredCallEntry* entry)
|
|
{
|
|
ASSERT(m_in_critical);
|
|
entry->next = m_pending_deferred_calls;
|
|
m_pending_deferred_calls = entry;
|
|
}
|
|
|
|
void Processor::deferred_call_queue(void (*callback)())
|
|
{
|
|
// NOTE: If we are called outside of a critical section and outside
|
|
// of an irq handler, the function will be executed before we return!
|
|
ScopedCritical critical;
|
|
auto& cur_proc = Processor::current();
|
|
|
|
auto* entry = cur_proc.deferred_call_get_free();
|
|
entry->have_data = false;
|
|
entry->callback.handler = callback;
|
|
|
|
cur_proc.deferred_call_queue_entry(entry);
|
|
}
|
|
|
|
void Processor::deferred_call_queue(void (*callback)(void*), void* data, void (*free_data)(void*))
|
|
{
|
|
// NOTE: If we are called outside of a critical section and outside
|
|
// of an irq handler, the function will be executed before we return!
|
|
ScopedCritical critical;
|
|
auto& cur_proc = Processor::current();
|
|
|
|
auto* entry = cur_proc.deferred_call_get_free();
|
|
entry->have_data = true;
|
|
entry->callback_with_data.handler = callback;
|
|
entry->callback_with_data.data = data;
|
|
entry->callback_with_data.free = free_data;
|
|
|
|
cur_proc.deferred_call_queue_entry(entry);
|
|
}
|
|
|
|
void Processor::gdt_init()
|
|
{
|
|
m_gdt_length = 0;
|
|
m_gdtr.address = nullptr;
|
|
m_gdtr.limit = 0;
|
|
|
|
write_raw_gdt_entry(0x0000, 0x00000000, 0x00000000);
|
|
write_raw_gdt_entry(GDT_SELECTOR_CODE0, 0x0000ffff, 0x00cf9a00); // code0
|
|
write_raw_gdt_entry(GDT_SELECTOR_DATA0, 0x0000ffff, 0x00cf9200); // data0
|
|
write_raw_gdt_entry(GDT_SELECTOR_CODE3, 0x0000ffff, 0x00cffa00); // code3
|
|
write_raw_gdt_entry(GDT_SELECTOR_DATA3, 0x0000ffff, 0x00cff200); // data3
|
|
|
|
Descriptor tls_descriptor;
|
|
tls_descriptor.low = tls_descriptor.high = 0;
|
|
tls_descriptor.dpl = 3;
|
|
tls_descriptor.segment_present = 1;
|
|
tls_descriptor.granularity = 0;
|
|
tls_descriptor.zero = 0;
|
|
tls_descriptor.operation_size = 1;
|
|
tls_descriptor.descriptor_type = 1;
|
|
tls_descriptor.type = 2;
|
|
write_gdt_entry(GDT_SELECTOR_TLS, tls_descriptor); // tls3
|
|
|
|
Descriptor fs_descriptor;
|
|
fs_descriptor.set_base(this);
|
|
fs_descriptor.set_limit(sizeof(Processor));
|
|
fs_descriptor.dpl = 0;
|
|
fs_descriptor.segment_present = 1;
|
|
fs_descriptor.granularity = 0;
|
|
fs_descriptor.zero = 0;
|
|
fs_descriptor.operation_size = 1;
|
|
fs_descriptor.descriptor_type = 1;
|
|
fs_descriptor.type = 2;
|
|
write_gdt_entry(GDT_SELECTOR_PROC, fs_descriptor); // fs0
|
|
|
|
Descriptor tss_descriptor;
|
|
tss_descriptor.set_base(&m_tss);
|
|
tss_descriptor.set_limit(sizeof(TSS32));
|
|
tss_descriptor.dpl = 0;
|
|
tss_descriptor.segment_present = 1;
|
|
tss_descriptor.granularity = 0;
|
|
tss_descriptor.zero = 0;
|
|
tss_descriptor.operation_size = 1;
|
|
tss_descriptor.descriptor_type = 0;
|
|
tss_descriptor.type = 9;
|
|
write_gdt_entry(GDT_SELECTOR_TSS, tss_descriptor); // tss
|
|
|
|
flush_gdt();
|
|
load_task_register(GDT_SELECTOR_TSS);
|
|
|
|
asm volatile(
|
|
"mov %%ax, %%ds\n"
|
|
"mov %%ax, %%es\n"
|
|
"mov %%ax, %%gs\n"
|
|
"mov %%ax, %%ss\n" ::"a"(GDT_SELECTOR_DATA0)
|
|
: "memory");
|
|
set_fs(GDT_SELECTOR_PROC);
|
|
|
|
// Make sure CS points to the kernel code descriptor.
|
|
asm volatile(
|
|
"ljmpl $" __STRINGIFY(GDT_SELECTOR_CODE0) ", $sanity\n"
|
|
"sanity:\n");
|
|
}
|
|
|
|
void Processor::set_thread_specific(u8* data, size_t len)
|
|
{
|
|
auto& descriptor = get_gdt_entry(GDT_SELECTOR_TLS);
|
|
descriptor.set_base(data);
|
|
descriptor.set_limit(len);
|
|
}
|
|
|
|
}
|
|
|
|
#ifdef DEBUG
|
|
void __assertion_failed(const char* msg, const char* file, unsigned line, const char* func)
|
|
{
|
|
asm volatile("cli");
|
|
klog() << "ASSERTION FAILED: " << msg << "\n"
|
|
<< file << ":" << line << " in " << func;
|
|
|
|
// Switch back to the current process's page tables if there are any.
|
|
// Otherwise stack walking will be a disaster.
|
|
auto process = Process::current();
|
|
if (process)
|
|
MM.enter_process_paging_scope(*process);
|
|
|
|
Kernel::dump_backtrace();
|
|
Processor::halt();
|
|
}
|
|
#endif
|
|
|
|
NonMaskableInterruptDisabler::NonMaskableInterruptDisabler()
|
|
{
|
|
IO::out8(0x70, IO::in8(0x70) | 0x80);
|
|
}
|
|
|
|
NonMaskableInterruptDisabler::~NonMaskableInterruptDisabler()
|
|
{
|
|
IO::out8(0x70, IO::in8(0x70) & 0x7F);
|
|
}
|