2 * AcessOS Microkernel Version
17 #define DEBUG_TRACE_SWITCH 0
18 #define DEBUG_DISABLE_DOUBLEFAULT 1
19 #define DEBUG_VERY_SLOW_SWITCH 0
23 #define TIMER_BASE 1193182
24 #if DEBUG_VERY_SLOW_PERIOD
25 # define TIMER_DIVISOR 1193 //~10Hz switch, with 10 quantum = 1s per thread
27 # define TIMER_DIVISOR 11932 //~100Hz
34 Uint8 State; // 0: Unavaliable, 1: Idle, 2: Active
43 extern void APWait(void); // 16-bit AP pause code
44 extern void APStartup(void); // 16-bit AP startup code
45 extern Uint GetEIP(void); // start.asm
46 extern Uint GetEIP_Sched(void); // proc.asm
47 extern void NewTaskHeader(tThread *Thread, void *Fcn, int nArgs, ...); // Actually takes cdecl args
48 extern Uint Proc_CloneInt(Uint *ESP, Uint32 *CR3);
49 extern Uint32 gaInitPageDir[1024]; // start.asm
50 extern char Kernel_Stack_Top[];
53 extern tThread gThreadZero;
54 extern void Isr8(void); // Double Fault
55 extern void Proc_ReturnToUser(tVAddr Handler, Uint Argument, tVAddr KernelStack);
56 extern char scheduler_return[]; // Return address in SchedulerBase
57 extern char IRQCommon[]; // Common IRQ handler code
58 extern char IRQCommon_handled[]; // IRQCommon call return location
59 extern char GetEIP_Sched_ret[]; // GetEIP call return location
60 extern void SwitchTasks(Uint NewSP, Uint *OldSP, Uint NewIP, Uint *OldIO, Uint CR3);
61 extern void Proc_InitialiseSSE(void);
62 extern void Proc_SaveSSE(Uint DestPtr);
63 extern void Proc_DisableSSE(void);
66 //void ArchThreads_Init(void);
68 void MP_StartAP(int CPU);
69 void MP_SendIPI(Uint8 APICID, int Vector, int DeliveryMode);
71 void Proc_IdleThread(void *Ptr);
72 //void Proc_Start(void);
73 //tThread *Proc_GetCurThread(void);
74 void Proc_ChangeStack(void);
75 // int Proc_NewKThread(void (*Fcn)(void*), void *Data);
76 // int Proc_Clone(Uint *Err, Uint Flags);
77 Uint Proc_MakeUserStack(void);
78 //void Proc_StartUser(Uint Entrypoint, Uint *Bases, int ArgC, char **ArgV, char **EnvP, int DataSize);
79 void Proc_StartProcess(Uint16 SS, Uint Stack, Uint Flags, Uint16 CS, Uint IP) NORETURN;
80 int Proc_Demote(Uint *Err, int Dest, tRegs *Regs);
81 //void Proc_CallFaultHandler(tThread *Thread);
82 //void Proc_DumpThreadCPUState(tThread *Thread);
83 void Proc_Scheduler(int CPU);
86 // --- Multiprocessing ---
88 volatile int giNumInitingCPUs = 0;
89 tMPInfo *gMPFloatPtr = NULL;
90 volatile Uint32 giMP_TimerCount; // Start Count for Local APIC Timer
91 tAPIC *gpMP_LocalAPIC = NULL;
92 Uint8 gaAPIC_to_CPU[256] = {0};
93 int giProc_BootProcessorID = 0;
94 tTSS gaTSSs[MAX_CPUS]; // TSS Array
96 tCPU gaCPUs[MAX_CPUS] = {
97 {.Current = &gThreadZero}
99 tTSS *gTSSs = NULL; // Pointer to TSS array
101 // --- Error Recovery ---
102 char gaDoubleFaultStack[1024] __attribute__ ((section(".padata")));
103 tTSS gDoubleFault_TSS = {
104 .ESP0 = (Uint)&gaDoubleFaultStack[1024],
106 .CR3 = (Uint)gaInitPageDir - KERNEL_BASE,
108 .ESP = (Uint)&gaDoubleFaultStack[1024],
109 .CS = 0x08, .SS = 0x10,
110 .DS = 0x10, .ES = 0x10,
111 .FS = 0x10, .GS = 0x10,
116 * \fn void ArchThreads_Init(void)
117 * \brief Starts the process scheduler
119 void ArchThreads_Init(void)
126 // Mark BSP as active
129 // -- Initialise Multiprocessing
130 // Find MP Floating Table
131 // - EBDA/Last 1Kib (640KiB)
132 for(pos = KERNEL_BASE|0x9F000; pos < (KERNEL_BASE|0xA0000); pos += 16) {
133 if( *(Uint*)(pos) == MPPTR_IDENT ) {
134 Log("Possible %p", pos);
135 if( ByteSum((void*)pos, sizeof(tMPInfo)) != 0 ) continue;
136 gMPFloatPtr = (void*)pos;
140 // - Last KiB (512KiB base mem)
142 for(pos = KERNEL_BASE|0x7F000; pos < (KERNEL_BASE|0x80000); pos += 16) {
143 if( *(Uint*)(pos) == MPPTR_IDENT ) {
144 Log("Possible %p", pos);
145 if( ByteSum((void*)pos, sizeof(tMPInfo)) != 0 ) continue;
146 gMPFloatPtr = (void*)pos;
153 for(pos = KERNEL_BASE|0xE0000; pos < (KERNEL_BASE|0x100000); pos += 16) {
154 if( *(Uint*)(pos) == MPPTR_IDENT ) {
155 Log("Possible %p", pos);
156 if( ByteSum((void*)pos, sizeof(tMPInfo)) != 0 ) continue;
157 gMPFloatPtr = (void*)pos;
163 // If the MP Table Exists, parse it
168 Log("gMPFloatPtr = %p", gMPFloatPtr);
169 Log("*gMPFloatPtr = {");
170 Log("\t.Sig = 0x%08x", gMPFloatPtr->Sig);
171 Log("\t.MPConfig = 0x%08x", gMPFloatPtr->MPConfig);
172 Log("\t.Length = 0x%02x", gMPFloatPtr->Length);
173 Log("\t.Version = 0x%02x", gMPFloatPtr->Version);
174 Log("\t.Checksum = 0x%02x", gMPFloatPtr->Checksum);
175 Log("\t.Features = [0x%02x,0x%02x,0x%02x,0x%02x,0x%02x]",
176 gMPFloatPtr->Features[0], gMPFloatPtr->Features[1],
177 gMPFloatPtr->Features[2], gMPFloatPtr->Features[3],
178 gMPFloatPtr->Features[4]
182 mptable = (void*)( KERNEL_BASE|gMPFloatPtr->MPConfig );
183 Log("mptable = %p", mptable);
185 Log("\t.Sig = 0x%08x", mptable->Sig);
186 Log("\t.BaseTableLength = 0x%04x", mptable->BaseTableLength);
187 Log("\t.SpecRev = 0x%02x", mptable->SpecRev);
188 Log("\t.Checksum = 0x%02x", mptable->Checksum);
189 Log("\t.OEMID = '%8c'", mptable->OemID);
190 Log("\t.ProductID = '%8c'", mptable->ProductID);
191 Log("\t.OEMTablePtr = %p'", mptable->OEMTablePtr);
192 Log("\t.OEMTableSize = 0x%04x", mptable->OEMTableSize);
193 Log("\t.EntryCount = 0x%04x", mptable->EntryCount);
194 Log("\t.LocalAPICMemMap = 0x%08x", mptable->LocalAPICMemMap);
195 Log("\t.ExtendedTableLen = 0x%04x", mptable->ExtendedTableLen);
196 Log("\t.ExtendedTableChecksum = 0x%02x", mptable->ExtendedTableChecksum);
199 gpMP_LocalAPIC = (void*)MM_MapHWPages(mptable->LocalAPICMemMap, 1);
201 ents = mptable->Entries;
204 for( i = 0; i < mptable->EntryCount; i ++ )
211 Log("%i: Processor", i);
212 Log("\t.APICID = %i", ents->Proc.APICID);
213 Log("\t.APICVer = 0x%02x", ents->Proc.APICVer);
214 Log("\t.CPUFlags = 0x%02x", ents->Proc.CPUFlags);
215 Log("\t.CPUSignature = 0x%08x", ents->Proc.CPUSignature);
216 Log("\t.FeatureFlags = 0x%08x", ents->Proc.FeatureFlags);
219 if( !(ents->Proc.CPUFlags & 1) ) {
224 // Check if there is too many processors
225 if(giNumCPUs >= MAX_CPUS) {
226 giNumCPUs ++; // If `giNumCPUs` > MAX_CPUS later, it will be clipped
230 // Initialise CPU Info
231 gaAPIC_to_CPU[ents->Proc.APICID] = giNumCPUs;
232 gaCPUs[giNumCPUs].APICID = ents->Proc.APICID;
233 gaCPUs[giNumCPUs].State = 0;
237 if( ents->Proc.CPUFlags & 2 ) {
238 giProc_BootProcessorID = giNumCPUs-1;
247 Log("\t.ID = %i", ents->Bus.ID);
248 Log("\t.TypeString = '%6C'", ents->Bus.TypeString);
252 Log("%i: I/O APIC", i);
253 Log("\t.ID = %i", ents->IOAPIC.ID);
254 Log("\t.Version = 0x%02x", ents->IOAPIC.Version);
255 Log("\t.Flags = 0x%02x", ents->IOAPIC.Flags);
256 Log("\t.Addr = 0x%08x", ents->IOAPIC.Addr);
258 case 3: // I/O Interrupt Assignment
260 Log("%i: I/O Interrupt Assignment", i);
261 Log("\t.IntType = %i", ents->IOInt.IntType);
262 Log("\t.Flags = 0x%04x", ents->IOInt.Flags);
263 Log("\t.SourceBusID = 0x%02x", ents->IOInt.SourceBusID);
264 Log("\t.SourceBusIRQ = 0x%02x", ents->IOInt.SourceBusIRQ);
265 Log("\t.DestAPICID = 0x%02x", ents->IOInt.DestAPICID);
266 Log("\t.DestAPICIRQ = 0x%02x", ents->IOInt.DestAPICIRQ);
268 case 4: // Local Interrupt Assignment
270 Log("%i: Local Interrupt Assignment", i);
271 Log("\t.IntType = %i", ents->LocalInt.IntType);
272 Log("\t.Flags = 0x%04x", ents->LocalInt.Flags);
273 Log("\t.SourceBusID = 0x%02x", ents->LocalInt.SourceBusID);
274 Log("\t.SourceBusIRQ = 0x%02x", ents->LocalInt.SourceBusIRQ);
275 Log("\t.DestLocalAPICID = 0x%02x", ents->LocalInt.DestLocalAPICID);
276 Log("\t.DestLocalAPICIRQ = 0x%02x", ents->LocalInt.DestLocalAPICIRQ);
279 Log("%i: Unknown (%i)", i, ents->Type);
283 ents = (void*)( (Uint)ents + entSize );
286 if( giNumCPUs > MAX_CPUS ) {
287 Warning("Too many CPUs detected (%i), only using %i of them", giNumCPUs, MAX_CPUS);
288 giNumCPUs = MAX_CPUS;
293 Log("No MP Table was found, assuming uniprocessor\n");
302 #if !DEBUG_DISABLE_DOUBLEFAULT
303 // Initialise Double Fault TSS
304 gGDT[5].BaseLow = (Uint)&gDoubleFault_TSS & 0xFFFF;
305 gGDT[5].BaseMid = (Uint)&gDoubleFault_TSS >> 16;
306 gGDT[5].BaseHi = (Uint)&gDoubleFault_TSS >> 24;
308 // Set double fault IDT to use the new TSS
309 gIDT[8].OffsetLo = 0;
311 gIDT[8].Flags = 0x8500;
312 gIDT[8].OffsetHi = 0;
315 // Set timer frequency
316 outb(0x43, 0x34); // Set Channel 0, Low/High, Rate Generator
317 outb(0x40, TIMER_DIVISOR&0xFF); // Low Byte of Divisor
318 outb(0x40, (TIMER_DIVISOR>>8)&0xFF); // High Byte
320 Log_Debug("Proc", "PIT Frequency %i.%03i Hz",
321 TIMER_BASE/TIMER_DIVISOR,
322 ((Uint64)TIMER_BASE*1000/TIMER_DIVISOR)%1000
326 // Get the count setting for APIC timer
327 Log("Determining APIC Count");
328 __asm__ __volatile__ ("sti");
329 while( giMP_TimerCount == 0 ) __asm__ __volatile__ ("hlt");
330 __asm__ __volatile__ ("cli");
331 Log("APIC Count %i", giMP_TimerCount);
333 Uint64 freq = giMP_TimerCount;
334 freq /= TIMER_DIVISOR;
336 if( (freq /= 1000) < 2*1000)
337 Log("Bus Frequency %i KHz", freq);
338 else if( (freq /= 1000) < 2*1000)
339 Log("Bus Frequency %i MHz", freq);
340 else if( (freq /= 1000) < 2*1000)
341 Log("Bus Frequency %i GHz", freq);
343 Log("Bus Frequency %i THz", freq);
346 // Initialise Normal TSS(s)
347 for(pos=0;pos<giNumCPUs;pos++)
352 gTSSs[pos].SS0 = 0x10;
353 gTSSs[pos].ESP0 = 0; // Set properly by scheduler
354 gGDT[6+pos].BaseLow = ((Uint)(&gTSSs[pos])) & 0xFFFF;
355 gGDT[6+pos].BaseMid = ((Uint)(&gTSSs[pos]) >> 16) & 0xFFFF;
356 gGDT[6+pos].BaseHi = ((Uint)(&gTSSs[pos])) >> 24;
361 // Load the BSP's TSS
362 __asm__ __volatile__ ("ltr %%ax"::"a"(0x30));
363 // Set Current Thread and CPU Number in DR0 and DR1
364 __asm__ __volatile__ ("mov %0, %%db0"::"r"(&gThreadZero));
365 __asm__ __volatile__ ("mov %0, %%db1"::"r"(0));
367 gaCPUs[0].Current = &gThreadZero;
368 gThreadZero.CurCPU = 0;
370 gThreadZero.MemState.CR3 = (Uint)gaInitPageDir - KERNEL_BASE;
372 // Create Per-Process Data Block
373 if( !MM_Allocate(MM_PPD_CFG) )
375 Panic("OOM - No space for initial Per-Process Config");
378 // Initialise SSE support
379 Proc_InitialiseSSE();
386 void MP_StartAP(int CPU)
388 Log("Starting AP %i (APIC %i)", CPU, gaCPUs[CPU].APICID);
390 // Set location of AP startup code and mark for a warm restart
391 *(Uint16*)(KERNEL_BASE|0x467) = (Uint)&APWait - (KERNEL_BASE|0xFFFF0);
392 *(Uint16*)(KERNEL_BASE|0x469) = 0xFFFF;
393 outb(0x70, 0x0F); outb(0x71, 0x0A); // Set warm reset flag
394 MP_SendIPI(gaCPUs[CPU].APICID, 0, 5); // Init IPI
397 inb(0x80); inb(0x80); inb(0x80); inb(0x80);
399 // TODO: Use a better address, preferably registered with the MM
400 // - MM_AllocDMA mabye?
402 *(Uint8*)(KERNEL_BASE|0x11000) = 0xEA; // Far JMP
403 *(Uint16*)(KERNEL_BASE|0x11001) = (Uint)&APStartup - (KERNEL_BASE|0xFFFF0); // IP
404 *(Uint16*)(KERNEL_BASE|0x11003) = 0xFFFF; // CS
405 // Send a Startup-IPI to make the CPU execute at 0x11000 (which we
407 MP_SendIPI(gaCPUs[CPU].APICID, 0x11, 6); // StartupIPI
413 * \brief Send an Inter-Processor Interrupt
414 * \param APICID Processor's Local APIC ID
415 * \param Vector Argument of some kind
416 * \param DeliveryMode Type of signal?
418 void MP_SendIPI(Uint8 APICID, int Vector, int DeliveryMode)
423 val = (Uint)APICID << 24;
424 Log("*%p = 0x%08x", &gpMP_LocalAPIC->ICR[1], val);
425 gpMP_LocalAPIC->ICR[1].Val = val;
427 val = ((DeliveryMode & 7) << 8) | (Vector & 0xFF);
428 Log("*%p = 0x%08x", &gpMP_LocalAPIC->ICR[0], val);
429 gpMP_LocalAPIC->ICR[0].Val = val;
433 void Proc_IdleThread(void *Ptr)
436 cpu->IdleThread->ThreadName = strdup("Idle Thread");
437 Threads_SetPriority( cpu->IdleThread, -1 ); // Never called randomly
438 cpu->IdleThread->Quantum = 1; // 1 slice quantum
446 * \fn void Proc_Start(void)
447 * \brief Start process scheduler
449 void Proc_Start(void)
458 for( i = 0; i < giNumCPUs; i ++ )
460 if(i) gaCPUs[i].Current = NULL;
463 tid = Proc_NewKThread(Proc_IdleThread, &gaCPUs[i]);
464 gaCPUs[i].IdleThread = Threads_GetThread(tid);
467 if( i != giProc_BootProcessorID ) {
472 // BSP still should run the current task
473 gaCPUs[0].Current = &gThreadZero;
475 // Start interrupts and wait for APs to come up
476 Log("Waiting for APs to come up\n");
477 __asm__ __volatile__ ("sti");
478 while( giNumInitingCPUs ) __asm__ __volatile__ ("hlt");
481 tid = Proc_NewKThread(Proc_IdleThread, &gaCPUs[0]);
482 gaCPUs[0].IdleThread = Threads_GetThread(tid);
485 gaCPUs[0].Current = &gThreadZero;
487 // while( gaCPUs[0].IdleThread == NULL )
490 // Start Interrupts (and hence scheduler)
491 __asm__ __volatile__("sti");
493 MM_FinishVirtualInit();
497 * \fn tThread *Proc_GetCurThread(void)
498 * \brief Gets the current thread
500 tThread *Proc_GetCurThread(void)
503 return gaCPUs[ GetCPUNum() ].Current;
505 return gaCPUs[ 0 ].Current;
510 * \fn void Proc_ChangeStack(void)
511 * \brief Swaps the current stack for a new one (in the proper stack reigon)
513 void Proc_ChangeStack(void)
517 Uint curBase, newBase;
519 __asm__ __volatile__ ("mov %%esp, %0":"=r"(esp));
520 __asm__ __volatile__ ("mov %%ebp, %0":"=r"(ebp));
525 newBase = MM_NewKStack();
528 Panic("What the?? Unable to allocate space for initial kernel stack");
532 curBase = (Uint)&Kernel_Stack_Top;
534 LOG("curBase = 0x%x, newBase = 0x%x", curBase, newBase);
536 // Get ESP as a used size
538 LOG("memcpy( %p, %p, 0x%x )", (void*)(newBase - esp), (void*)(curBase - esp), esp );
540 memcpy( (void*)(newBase - esp), (void*)(curBase - esp), esp );
541 // Get ESP as an offset in the new stack
544 ebp = newBase - (curBase - ebp);
546 // Repair EBPs & Stack Addresses
547 // Catches arguments also, but may trash stack-address-like values
548 for(tmpEbp = esp; tmpEbp < newBase; tmpEbp += 4)
550 if(oldEsp < *(Uint*)tmpEbp && *(Uint*)tmpEbp < curBase)
551 *(Uint*)tmpEbp += newBase - curBase;
554 Proc_GetCurThread()->KernelStack = newBase;
556 __asm__ __volatile__ ("mov %0, %%esp"::"r"(esp));
557 __asm__ __volatile__ ("mov %0, %%ebp"::"r"(ebp));
560 void Proc_ClearThread(tThread *Thread)
562 Log_Warning("Proc", "TODO: Nuke address space etc");
563 if(Thread->SavedState.SSE) {
564 free(Thread->SavedState.SSE);
565 Thread->SavedState.SSE = NULL;
569 int Proc_NewKThread(void (*Fcn)(void*), void *Data)
572 tThread *newThread, *cur;
574 cur = Proc_GetCurThread();
575 newThread = Threads_CloneTCB(0);
576 if(!newThread) return -1;
579 newThread->MemState.CR3 = cur->MemState.CR3;
582 newThread->KernelStack = MM_NewKStack();
584 if(newThread->KernelStack == 0) {
589 esp = newThread->KernelStack;
590 *(Uint*)(esp-=4) = (Uint)Data; // Data (shadowed)
591 *(Uint*)(esp-=4) = 1; // Number of params
592 *(Uint*)(esp-=4) = (Uint)Fcn; // Function to call
593 *(Uint*)(esp-=4) = (Uint)newThread; // Thread ID
595 newThread->SavedState.ESP = esp;
596 newThread->SavedState.EIP = (Uint)&NewTaskHeader;
597 newThread->SavedState.SSE = NULL;
598 // Log("New (KThread) %p, esp = %p", newThread->SavedState.EIP, newThread->SavedState.ESP);
601 Threads_AddActive(newThread);
603 return newThread->TID;
607 * \fn int Proc_Clone(Uint *Err, Uint Flags)
608 * \brief Clone the current process
610 int Proc_Clone(Uint Flags)
613 tThread *cur = Proc_GetCurThread();
617 if( !(Flags & CLONE_VM) ) {
618 Log_Error("Proc", "Proc_Clone: Don't leave CLONE_VM unset, use Proc_NewKThread instead");
623 newThread = Threads_CloneTCB(Flags);
624 if(!newThread) return -1;
626 newThread->KernelStack = cur->KernelStack;
629 eip = Proc_CloneInt(&newThread->SavedState.ESP, &newThread->MemState.CR3);
634 newThread->SavedState.EIP = eip;
635 newThread->SavedState.SSE = NULL;
636 newThread->SavedState.bSSEModified = 0;
639 if( newThread->MemState.CR3 == 0 ) {
640 Log_Error("Proc", "Proc_Clone: MM_Clone failed");
641 Threads_Delete(newThread);
645 // Add the new thread to the run queue
646 Threads_AddActive(newThread);
647 return newThread->TID;
651 * \fn int Proc_SpawnWorker(void)
652 * \brief Spawns a new worker thread
654 int Proc_SpawnWorker(void (*Fcn)(void*), void *Data)
657 Uint stack_contents[4];
660 new = Threads_CloneThreadZero();
662 Warning("Proc_SpawnWorker - Out of heap space!\n");
666 // Create the stack contents
667 stack_contents[3] = (Uint)Data;
668 stack_contents[2] = 1;
669 stack_contents[1] = (Uint)Fcn;
670 stack_contents[0] = (Uint)new;
672 // Create a new worker stack (in PID0's address space)
673 new->KernelStack = MM_NewWorkerStack(stack_contents, sizeof(stack_contents));
675 // Save core machine state
676 new->SavedState.ESP = new->KernelStack - sizeof(stack_contents);
677 new->SavedState.EIP = (Uint)NewTaskHeader;
678 new->SavedState.SSE = NULL;
679 new->SavedState.bSSEModified = 0;
682 new->Status = THREAD_STAT_PREINIT;
683 Threads_AddActive( new );
689 * \fn Uint Proc_MakeUserStack(void)
690 * \brief Creates a new user stack
692 Uint Proc_MakeUserStack(void)
695 Uint base = USER_STACK_TOP - USER_STACK_SZ;
697 // Check Prospective Space
698 for( i = USER_STACK_SZ >> 12; i--; )
699 if( MM_GetPhysAddr( base + (i<<12) ) != 0 )
702 if(i != -1) return 0;
704 // Allocate Stack - Allocate incrementally to clean up MM_Dump output
705 for( i = 0; i < USER_STACK_SZ/0x1000; i++ )
707 if( !MM_Allocate( base + (i<<12) ) )
709 Warning("OOM: Proc_MakeUserStack");
714 return base + USER_STACK_SZ;
717 void Proc_StartUser(Uint Entrypoint, Uint Base, int ArgC, char **ArgV, int DataSize)
724 // Copy data to the user stack and free original buffer
725 stack = (void*)Proc_MakeUserStack();
726 stack -= DataSize/sizeof(*stack);
727 memcpy( stack, ArgV, DataSize );
730 // Adjust Arguments and environment
733 Uint delta = (Uint)stack - (Uint)ArgV;
734 ArgV = (char**)stack;
735 for( i = 0; ArgV[i]; i++ ) ArgV[i] += delta;
737 for( i = 0; envp[i]; i++ ) envp[i] += delta;
740 // User Mode Segments
741 ss = 0x23; cs = 0x1B;
744 *--stack = (Uint)envp;
745 *--stack = (Uint)ArgV;
746 *--stack = (Uint)ArgC;
749 Proc_StartProcess(ss, (Uint)stack, 0x202, cs, Entrypoint);
752 void Proc_StartProcess(Uint16 SS, Uint Stack, Uint Flags, Uint16 CS, Uint IP)
754 Uint *stack = (void*)Stack;
755 *--stack = SS; //Stack Segment
756 *--stack = Stack; //Stack Pointer
757 *--stack = Flags; //EFLAGS (Resvd (0x2) and IF (0x20))
758 *--stack = CS; //Code Segment
761 *--stack = 0xAAAAAAAA; // eax
762 *--stack = 0xCCCCCCCC; // ecx
763 *--stack = 0xDDDDDDDD; // edx
764 *--stack = 0xBBBBBBBB; // ebx
765 *--stack = 0xD1D1D1D1; // edi
766 *--stack = 0x54545454; // esp - NOT POPED
767 *--stack = 0x51515151; // esi
768 *--stack = 0xB4B4B4B4; // ebp
775 __asm__ __volatile__ (
776 "mov %%eax,%%esp;\n\t" // Set stack pointer
782 "iret;\n\t" : : "a" (stack));
787 * \fn int Proc_Demote(Uint *Err, int Dest, tRegs *Regs)
788 * \brief Demotes a process to a lower permission level
789 * \param Err Pointer to user's errno
790 * \param Dest New Permission Level
791 * \param Regs Pointer to user's register structure
793 int Proc_Demote(Uint *Err, int Dest, tRegs *Regs)
795 int cpl = Regs->cs & 3;
797 if(Dest > 3 || Dest < 0) {
808 // Change the Segment Registers
809 Regs->cs = (((Dest+1)<<4) | Dest) - 8;
810 Regs->ss = ((Dest+1)<<4) | Dest;
811 // Check if the GP Segs are GDT, then change them
812 if(!(Regs->ds & 4)) Regs->ds = ((Dest+1)<<4) | Dest;
813 if(!(Regs->es & 4)) Regs->es = ((Dest+1)<<4) | Dest;
814 if(!(Regs->fs & 4)) Regs->fs = ((Dest+1)<<4) | Dest;
815 if(!(Regs->gs & 4)) Regs->gs = ((Dest+1)<<4) | Dest;
821 * \brief Calls a signal handler in user mode
822 * \note Used for signals
824 void Proc_CallFaultHandler(tThread *Thread)
826 // Rewinds the stack and calls the user function
828 Proc_ReturnToUser( Thread->FaultHandler, Thread->CurFaultNum, Thread->KernelStack );
832 void Proc_DumpThreadCPUState(tThread *Thread)
834 if( Thread->CurCPU > -1 )
836 int maxBacktraceDistance = 6;
840 if( Thread->CurCPU != GetCPUNum() ) {
841 Log(" Currently running");
845 // Backtrace to find the IRQ entrypoint
846 // - This will usually only be called by an IRQ, so this should
848 __asm__ __volatile__ ("mov %%ebp, %0" : "=r" (stack));
849 while( maxBacktraceDistance -- )
854 if( stack[1] == (tVAddr)&IRQCommon_handled ) {
855 regs = (void*)stack[2];
859 stack = (void*)stack[0];
863 Log(" Unable to find IRQ Entry");
867 Log(" at %04x:%08x", regs->cs, regs->eip);
871 tVAddr diffFromScheduler = Thread->SavedState.EIP - (tVAddr)SwitchTasks;
872 tVAddr diffFromClone = Thread->SavedState.EIP - (tVAddr)Proc_CloneInt;
873 tVAddr diffFromSpawn = Thread->SavedState.EIP - (tVAddr)NewTaskHeader;
875 if( diffFromClone > 0 && diffFromClone < 40 ) // When I last checked, .newTask was at .+27
877 Log(" Creating process");
881 if( diffFromSpawn == 0 )
883 Log(" Creating thread");
887 if( diffFromScheduler > 0 && diffFromScheduler < 128 ) // When I last checked, GetEIP was at .+0x30
890 Log(" At %04x:%08x", Thread->SavedState.UserCS, Thread->SavedState.UserEIP);
894 Log(" Just created (unknown %p)", Thread->SavedState.EIP);
897 void Proc_Reschedule(void)
899 tThread *nextthread, *curthread;
900 int cpu = GetCPUNum();
902 // TODO: Wait for the lock?
903 if(IS_LOCKED(&glThreadListLock)) return;
905 curthread = Proc_GetCurThread();
907 nextthread = Threads_GetNextToRun(cpu, curthread);
910 nextthread = gaCPUs[cpu].IdleThread;
911 if(!nextthread || nextthread == curthread)
914 #if DEBUG_TRACE_SWITCH
915 LogF("\nSwitching to task %i, CR3 = 0x%x, EIP = %p, ESP = %p\n",
917 nextthread->MemState.CR3,
918 nextthread->SavedState.EIP,
919 nextthread->SavedState.ESP
924 gaCPUs[cpu].Current = nextthread;
925 gTSSs[cpu].ESP0 = nextthread->KernelStack-4;
926 __asm__ __volatile__("mov %0, %%db0\n\t" : : "r"(nextthread) );
928 // Save FPU/MMX/XMM/SSE state
929 if( curthread->SavedState.SSE )
931 Proc_SaveSSE( ((Uint)curthread->SavedState.SSE + 0xF) & ~0xF );
932 curthread->SavedState.bSSEModified = 0;
937 nextthread->SavedState.ESP, &curthread->SavedState.ESP,
938 nextthread->SavedState.EIP, &curthread->SavedState.EIP,
939 nextthread->MemState.CR3
946 * \fn void Proc_Scheduler(int CPU)
947 * \brief Swap current thread and clears dead threads
949 void Proc_Scheduler(int CPU)
953 // If the spinlock is set, let it complete
954 if(IS_LOCKED(&glThreadListLock)) return;
956 // Get current thread
957 thread = gaCPUs[CPU].Current;
963 // Reduce remaining quantum and continue timeslice if non-zero
964 if( thread->Remaining-- )
966 // Reset quantum for next call
967 thread->Remaining = thread->Quantum;
969 // TODO: Make this more stable somehow
970 __asm__ __volatile__("mov %%ebp, %0" : "=r" (ebp));
971 regs = (tRegs*)(ebp+(2+2)*4); // EBP,Ret + CPU,CurThread
972 thread->SavedState.UserCS = regs->cs;
973 thread->SavedState.UserEIP = regs->eip;
975 if(thread->bInstrTrace) {
976 regs->eflags |= 0x100; // Set TF
977 Log("%p De-scheduled", thread);
980 regs->eflags &= ~0x100; // Clear TF
987 gpMP_LocalAPIC->EOI.Val = 0;
991 __asm__ __volatile__ ("sti");
997 EXPORT(Proc_SpawnWorker);