2 * AcessOS Microkernel Version
16 #define DEBUG_TRACE_SWITCH 0
17 #define DEBUG_DISABLE_DOUBLEFAULT 1
20 #define SWITCH_MAGIC 0xFF5317C8 // FF SWITCH - There is no code in this area
22 #define TIMER_BASE 1193182
23 #define TIMER_DIVISOR 11932 //~100Hz
30 Uint8 State; // 0: Unavaliable, 1: Idle, 2: Active
40 extern void APWait(void); // 16-bit AP pause code
41 extern void APStartup(void); // 16-bit AP startup code
42 extern Uint GetEIP(void); // start.asm
43 extern int GetCPUNum(void); // start.asm
44 extern Uint32 gaInitPageDir[1024]; // start.asm
45 extern char Kernel_Stack_Top[];
46 extern tShortSpinlock glThreadListLock;
49 extern tThread gThreadZero;
50 extern void Isr8(void); // Double Fault
51 extern void Proc_ReturnToUser(tVAddr Handler, Uint Argument, tVAddr KernelStack);
52 extern void scheduler_return; // Return address in SchedulerBase
53 extern void IRQCommon; // Common IRQ handler code
56 void ArchThreads_Init(void);
58 void MP_StartAP(int CPU);
59 void MP_SendIPI(Uint8 APICID, int Vector, int DeliveryMode);
61 //void Proc_Start(void);
62 //tThread *Proc_GetCurThread(void);
63 void Proc_ChangeStack(void);
64 // int Proc_Clone(Uint *Err, Uint Flags);
65 Uint Proc_MakeUserStack(void);
66 void Proc_StartUser(Uint Entrypoint, Uint *Bases, int ArgC, char **ArgV, char **EnvP, int DataSize);
67 void Proc_StartProcess(Uint16 SS, Uint Stack, Uint Flags, Uint16 CS, Uint IP);
68 int Proc_Demote(Uint *Err, int Dest, tRegs *Regs);
69 void Proc_CallFaultHandler(tThread *Thread);
70 void Proc_DumpThreadCPUState(tThread *Thread);
71 void Proc_Scheduler(int CPU);
74 // --- Multiprocessing ---
76 volatile int giNumInitingCPUs = 0;
77 tMPInfo *gMPFloatPtr = NULL;
78 volatile Uint32 giMP_TimerCount; // Start Count for Local APIC Timer
79 tAPIC *gpMP_LocalAPIC = NULL;
80 Uint8 gaAPIC_to_CPU[256] = {0};
81 tCPU gaCPUs[MAX_CPUS];
82 tTSS gaTSSs[MAX_CPUS]; // TSS Array
83 int giProc_BootProcessorID = 0;
85 tThread *gCurrentThread = NULL;
86 tThread *gpIdleThread = NULL;
89 Uint32 *gPML4s[4] = NULL;
91 tTSS *gTSSs = NULL; // Pointer to TSS array
93 // --- Error Recovery ---
94 char gaDoubleFaultStack[1024] __attribute__ ((section(".padata")));
95 tTSS gDoubleFault_TSS = {
96 .ESP0 = (Uint)&gaDoubleFaultStack[1024],
98 .CR3 = (Uint)gaInitPageDir - KERNEL_BASE,
100 .ESP = (Uint)&gaDoubleFaultStack[1024],
101 .CS = 0x08, .SS = 0x10,
102 .DS = 0x10, .ES = 0x10,
103 .FS = 0x10, .GS = 0x10,
108 * \fn void ArchThreads_Init(void)
109 * \brief Starts the process scheduler
111 void ArchThreads_Init(void)
118 // Mark BSP as active
121 // -- Initialise Multiprocessing
122 // Find MP Floating Table
123 // - EBDA/Last 1Kib (640KiB)
124 for(pos = KERNEL_BASE|0x9F000; pos < (KERNEL_BASE|0xA0000); pos += 16) {
125 if( *(Uint*)(pos) == MPPTR_IDENT ) {
126 Log("Possible %p", pos);
127 if( ByteSum((void*)pos, sizeof(tMPInfo)) != 0 ) continue;
128 gMPFloatPtr = (void*)pos;
132 // - Last KiB (512KiB base mem)
134 for(pos = KERNEL_BASE|0x7F000; pos < (KERNEL_BASE|0x80000); pos += 16) {
135 if( *(Uint*)(pos) == MPPTR_IDENT ) {
136 Log("Possible %p", pos);
137 if( ByteSum((void*)pos, sizeof(tMPInfo)) != 0 ) continue;
138 gMPFloatPtr = (void*)pos;
145 for(pos = KERNEL_BASE|0xE0000; pos < (KERNEL_BASE|0x100000); pos += 16) {
146 if( *(Uint*)(pos) == MPPTR_IDENT ) {
147 Log("Possible %p", pos);
148 if( ByteSum((void*)pos, sizeof(tMPInfo)) != 0 ) continue;
149 gMPFloatPtr = (void*)pos;
155 // If the MP Table Exists, parse it
160 Log("gMPFloatPtr = %p", gMPFloatPtr);
161 Log("*gMPFloatPtr = {");
162 Log("\t.Sig = 0x%08x", gMPFloatPtr->Sig);
163 Log("\t.MPConfig = 0x%08x", gMPFloatPtr->MPConfig);
164 Log("\t.Length = 0x%02x", gMPFloatPtr->Length);
165 Log("\t.Version = 0x%02x", gMPFloatPtr->Version);
166 Log("\t.Checksum = 0x%02x", gMPFloatPtr->Checksum);
167 Log("\t.Features = [0x%02x,0x%02x,0x%02x,0x%02x,0x%02x]",
168 gMPFloatPtr->Features[0], gMPFloatPtr->Features[1],
169 gMPFloatPtr->Features[2], gMPFloatPtr->Features[3],
170 gMPFloatPtr->Features[4]
174 mptable = (void*)( KERNEL_BASE|gMPFloatPtr->MPConfig );
175 Log("mptable = %p", mptable);
177 Log("\t.Sig = 0x%08x", mptable->Sig);
178 Log("\t.BaseTableLength = 0x%04x", mptable->BaseTableLength);
179 Log("\t.SpecRev = 0x%02x", mptable->SpecRev);
180 Log("\t.Checksum = 0x%02x", mptable->Checksum);
181 Log("\t.OEMID = '%8c'", mptable->OemID);
182 Log("\t.ProductID = '%8c'", mptable->ProductID);
183 Log("\t.OEMTablePtr = %p'", mptable->OEMTablePtr);
184 Log("\t.OEMTableSize = 0x%04x", mptable->OEMTableSize);
185 Log("\t.EntryCount = 0x%04x", mptable->EntryCount);
186 Log("\t.LocalAPICMemMap = 0x%08x", mptable->LocalAPICMemMap);
187 Log("\t.ExtendedTableLen = 0x%04x", mptable->ExtendedTableLen);
188 Log("\t.ExtendedTableChecksum = 0x%02x", mptable->ExtendedTableChecksum);
191 gpMP_LocalAPIC = (void*)MM_MapHWPages(mptable->LocalAPICMemMap, 1);
193 ents = mptable->Entries;
196 for( i = 0; i < mptable->EntryCount; i ++ )
203 Log("%i: Processor", i);
204 Log("\t.APICID = %i", ents->Proc.APICID);
205 Log("\t.APICVer = 0x%02x", ents->Proc.APICVer);
206 Log("\t.CPUFlags = 0x%02x", ents->Proc.CPUFlags);
207 Log("\t.CPUSignature = 0x%08x", ents->Proc.CPUSignature);
208 Log("\t.FeatureFlags = 0x%08x", ents->Proc.FeatureFlags);
211 if( !(ents->Proc.CPUFlags & 1) ) {
216 // Check if there is too many processors
217 if(giNumCPUs >= MAX_CPUS) {
218 giNumCPUs ++; // If `giNumCPUs` > MAX_CPUS later, it will be clipped
222 // Initialise CPU Info
223 gaAPIC_to_CPU[ents->Proc.APICID] = giNumCPUs;
224 gaCPUs[giNumCPUs].APICID = ents->Proc.APICID;
225 gaCPUs[giNumCPUs].State = 0;
229 if( ents->Proc.CPUFlags & 2 ) {
230 giProc_BootProcessorID = giNumCPUs-1;
239 Log("\t.ID = %i", ents->Bus.ID);
240 Log("\t.TypeString = '%6C'", ents->Bus.TypeString);
244 Log("%i: I/O APIC", i);
245 Log("\t.ID = %i", ents->IOAPIC.ID);
246 Log("\t.Version = 0x%02x", ents->IOAPIC.Version);
247 Log("\t.Flags = 0x%02x", ents->IOAPIC.Flags);
248 Log("\t.Addr = 0x%08x", ents->IOAPIC.Addr);
250 case 3: // I/O Interrupt Assignment
252 Log("%i: I/O Interrupt Assignment", i);
253 Log("\t.IntType = %i", ents->IOInt.IntType);
254 Log("\t.Flags = 0x%04x", ents->IOInt.Flags);
255 Log("\t.SourceBusID = 0x%02x", ents->IOInt.SourceBusID);
256 Log("\t.SourceBusIRQ = 0x%02x", ents->IOInt.SourceBusIRQ);
257 Log("\t.DestAPICID = 0x%02x", ents->IOInt.DestAPICID);
258 Log("\t.DestAPICIRQ = 0x%02x", ents->IOInt.DestAPICIRQ);
260 case 4: // Local Interrupt Assignment
262 Log("%i: Local Interrupt Assignment", i);
263 Log("\t.IntType = %i", ents->LocalInt.IntType);
264 Log("\t.Flags = 0x%04x", ents->LocalInt.Flags);
265 Log("\t.SourceBusID = 0x%02x", ents->LocalInt.SourceBusID);
266 Log("\t.SourceBusIRQ = 0x%02x", ents->LocalInt.SourceBusIRQ);
267 Log("\t.DestLocalAPICID = 0x%02x", ents->LocalInt.DestLocalAPICID);
268 Log("\t.DestLocalAPICIRQ = 0x%02x", ents->LocalInt.DestLocalAPICIRQ);
271 Log("%i: Unknown (%i)", i, ents->Type);
275 ents = (void*)( (Uint)ents + entSize );
278 if( giNumCPUs > MAX_CPUS ) {
279 Warning("Too many CPUs detected (%i), only using %i of them", giNumCPUs, MAX_CPUS);
280 giNumCPUs = MAX_CPUS;
285 Log("No MP Table was found, assuming uniprocessor\n");
292 MM_FinishVirtualInit();
295 #if !DEBUG_DISABLE_DOUBLEFAULT
296 // Initialise Double Fault TSS
297 gGDT[5].BaseLow = (Uint)&gDoubleFault_TSS & 0xFFFF;
298 gGDT[5].BaseMid = (Uint)&gDoubleFault_TSS >> 16;
299 gGDT[5].BaseHi = (Uint)&gDoubleFault_TSS >> 24;
301 // Set double fault IDT to use the new TSS
302 gIDT[8].OffsetLo = 0;
304 gIDT[8].Flags = 0x8500;
305 gIDT[8].OffsetHi = 0;
308 // Set timer frequency
309 outb(0x43, 0x34); // Set Channel 0, Low/High, Rate Generator
310 outb(0x40, TIMER_DIVISOR&0xFF); // Low Byte of Divisor
311 outb(0x40, (TIMER_DIVISOR>>8)&0xFF); // High Byte
313 Log("Timer Frequency %i.%03i Hz",
314 TIMER_BASE/TIMER_DIVISOR,
315 ((Uint64)TIMER_BASE*1000/TIMER_DIVISOR)%1000
319 // Get the count setting for APIC timer
320 Log("Determining APIC Count");
321 __asm__ __volatile__ ("sti");
322 while( giMP_TimerCount == 0 ) __asm__ __volatile__ ("hlt");
323 __asm__ __volatile__ ("cli");
324 Log("APIC Count %i", giMP_TimerCount);
326 Uint64 freq = giMP_TimerCount;
327 freq /= TIMER_DIVISOR;
329 if( (freq /= 1000) < 2*1000)
330 Log("Bus Frequency %i KHz", freq);
331 else if( (freq /= 1000) < 2*1000)
332 Log("Bus Frequency %i MHz", freq);
333 else if( (freq /= 1000) < 2*1000)
334 Log("Bus Frequency %i GHz", freq);
336 Log("Bus Frequency %i THz", freq);
339 // Initialise Normal TSS(s)
340 for(pos=0;pos<giNumCPUs;pos++)
345 gTSSs[pos].SS0 = 0x10;
346 gTSSs[pos].ESP0 = 0; // Set properly by scheduler
347 gGDT[6+pos].BaseLow = ((Uint)(&gTSSs[pos])) & 0xFFFF;
348 gGDT[6+pos].BaseMid = ((Uint)(&gTSSs[pos]) >> 16) & 0xFFFF;
349 gGDT[6+pos].BaseHi = ((Uint)(&gTSSs[pos])) >> 24;
354 // Load the BSP's TSS
355 __asm__ __volatile__ ("ltr %%ax"::"a"(0x30));
356 // Set Current Thread and CPU Number in DR0 and DR1
357 __asm__ __volatile__ ("mov %0, %%db0"::"r"(&gThreadZero));
358 __asm__ __volatile__ ("mov %0, %%db1"::"r"(0));
361 gaCPUs[0].Current = &gThreadZero;
363 gCurrentThread = &gThreadZero;
365 gThreadZero.CurCPU = 0;
368 gThreadZero.MemState.PDP[0] = 0;
369 gThreadZero.MemState.PDP[1] = 0;
370 gThreadZero.MemState.PDP[2] = 0;
372 gThreadZero.MemState.CR3 = (Uint)gaInitPageDir - KERNEL_BASE;
375 // Create Per-Process Data Block
376 if( !MM_Allocate(MM_PPD_CFG) )
378 Panic("OOM - No space for initiali Per-Process Config");
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;
434 * \fn void Proc_Start(void)
435 * \brief Start process scheduler
437 void Proc_Start(void)
445 for( i = 0; i < giNumCPUs; i ++ )
448 if(i) gaCPUs[i].Current = NULL;
451 if( (tid = Proc_Clone(0, 0)) == 0)
453 for(;;) HALT(); // Just yeilds
455 gaCPUs[i].IdleThread = Threads_GetThread(tid);
456 gaCPUs[i].IdleThread->ThreadName = (char*)"Idle Thread";
457 Threads_SetPriority( gaCPUs[i].IdleThread, -1 ); // Never called randomly
458 gaCPUs[i].IdleThread->Quantum = 1; // 1 slice quantum
462 if( i != giProc_BootProcessorID ) {
467 // BSP still should run the current task
468 gaCPUs[0].Current = &gThreadZero;
470 // Start interrupts and wait for APs to come up
471 Log("Waiting for APs to come up\n");
472 __asm__ __volatile__ ("sti");
473 while( giNumInitingCPUs ) __asm__ __volatile__ ("hlt");
476 if(Proc_Clone(0, 0) == 0)
478 gpIdleThread = Proc_GetCurThread();
479 gpIdleThread->ThreadName = strdup("Idle Thread");
480 Threads_SetPriority( gpIdleThread, -1 ); // Never called randomly
481 gpIdleThread->Quantum = 1; // 1 slice quantum
482 for(;;) HALT(); // Just yeilds
486 gCurrentThread = &gThreadZero;
488 // Start Interrupts (and hence scheduler)
489 __asm__ __volatile__("sti");
491 MM_FinishVirtualInit();
495 * \fn tThread *Proc_GetCurThread(void)
496 * \brief Gets the current thread
498 tThread *Proc_GetCurThread(void)
501 return gaCPUs[ GetCPUNum() ].Current;
503 return gCurrentThread;
508 * \fn void Proc_ChangeStack(void)
509 * \brief Swaps the current stack for a new one (in the proper stack reigon)
511 void Proc_ChangeStack(void)
515 Uint curBase, newBase;
517 __asm__ __volatile__ ("mov %%esp, %0":"=r"(esp));
518 __asm__ __volatile__ ("mov %%ebp, %0":"=r"(ebp));
523 newBase = MM_NewKStack();
526 Panic("What the?? Unable to allocate space for initial kernel stack");
530 curBase = (Uint)&Kernel_Stack_Top;
532 LOG("curBase = 0x%x, newBase = 0x%x", curBase, newBase);
534 // Get ESP as a used size
536 LOG("memcpy( %p, %p, 0x%x )", (void*)(newBase - esp), (void*)(curBase - esp), esp );
538 memcpy( (void*)(newBase - esp), (void*)(curBase - esp), esp );
539 // Get ESP as an offset in the new stack
542 ebp = newBase - (curBase - ebp);
544 // Repair EBPs & Stack Addresses
545 // Catches arguments also, but may trash stack-address-like values
546 for(tmpEbp = esp; tmpEbp < newBase; tmpEbp += 4)
548 if(oldEsp < *(Uint*)tmpEbp && *(Uint*)tmpEbp < curBase)
549 *(Uint*)tmpEbp += newBase - curBase;
552 Proc_GetCurThread()->KernelStack = newBase;
554 __asm__ __volatile__ ("mov %0, %%esp"::"r"(esp));
555 __asm__ __volatile__ ("mov %0, %%ebp"::"r"(ebp));
559 * \fn int Proc_Clone(Uint *Err, Uint Flags)
560 * \brief Clone the current process
562 int Proc_Clone(Uint *Err, Uint Flags)
565 tThread *cur = Proc_GetCurThread();
568 __asm__ __volatile__ ("mov %%esp, %0": "=r"(esp));
569 __asm__ __volatile__ ("mov %%ebp, %0": "=r"(ebp));
571 newThread = Threads_CloneTCB(Err, Flags);
572 if(!newThread) return -1;
574 // Initialise Memory Space (New Addr space or kernel stack)
575 if(Flags & CLONE_VM) {
576 newThread->MemState.CR3 = MM_Clone();
578 if(newThread->MemState.CR3 == 0) {
579 Threads_Kill(newThread, -2);
582 newThread->KernelStack = cur->KernelStack;
584 Uint tmpEbp, oldEsp = esp;
588 # warning "PAE Unimplemented"
590 newThread->MemState.CR3 = cur->MemState.CR3;
594 newThread->KernelStack = MM_NewKStack();
596 if(newThread->KernelStack == 0) {
597 Threads_Kill(newThread, -2);
601 // Get ESP as a used size
602 esp = cur->KernelStack - esp;
604 memcpy( (void*)(newThread->KernelStack - esp), (void*)(cur->KernelStack - esp), esp );
605 // Get ESP as an offset in the new stack
606 esp = newThread->KernelStack - esp;
608 ebp = newThread->KernelStack - (cur->KernelStack - ebp);
610 // Repair EBPs & Stack Addresses
611 // Catches arguments also, but may trash stack-address-like values
612 for(tmpEbp = esp; tmpEbp < newThread->KernelStack; tmpEbp += 4)
614 if(oldEsp < *(Uint*)tmpEbp && *(Uint*)tmpEbp < cur->KernelStack)
615 *(Uint*)tmpEbp += newThread->KernelStack - cur->KernelStack;
619 // Save core machine state
620 newThread->SavedState.ESP = esp;
621 newThread->SavedState.EBP = ebp;
623 if(eip == SWITCH_MAGIC) {
624 __asm__ __volatile__ ("mov %0, %%db0" : : "r" (newThread) );
628 gpMP_LocalAPIC->EOI.Val = 0;
631 outb(0x20, 0x20); // ACK Timer and return as child
632 __asm__ __volatile__ ("sti"); // Restart interrupts
637 newThread->SavedState.EIP = eip;
639 // Lock list and add to active
640 Threads_AddActive(newThread);
642 return newThread->TID;
646 * \fn int Proc_SpawnWorker(void)
647 * \brief Spawns a new worker thread
649 int Proc_SpawnWorker(void)
654 cur = Proc_GetCurThread();
657 new = Threads_CloneThreadZero();
659 Warning("Proc_SpawnWorker - Out of heap space!\n");
662 // Create a new worker stack (in PID0's address space)
663 // - The stack is relocated by this function
664 new->KernelStack = MM_NewWorkerStack();
666 // Get ESP and EBP based in the new stack
667 __asm__ __volatile__ ("mov %%esp, %0": "=r"(esp));
668 __asm__ __volatile__ ("mov %%ebp, %0": "=r"(ebp));
669 esp = new->KernelStack - (cur->KernelStack - esp);
670 ebp = new->KernelStack - (cur->KernelStack - ebp);
672 // Save core machine state
673 new->SavedState.ESP = esp;
674 new->SavedState.EBP = ebp;
676 if(eip == SWITCH_MAGIC) {
677 __asm__ __volatile__ ("mov %0, %%db0" : : "r"(new));
681 gpMP_LocalAPIC->EOI.Val = 0;
684 outb(0x20, 0x20); // ACK Timer and return as child
685 __asm__ __volatile__ ("sti"); // Restart interrupts
690 new->SavedState.EIP = eip;
692 Threads_AddActive( new );
698 * \fn Uint Proc_MakeUserStack(void)
699 * \brief Creates a new user stack
701 Uint Proc_MakeUserStack(void)
704 Uint base = USER_STACK_TOP - USER_STACK_SZ;
706 // Check Prospective Space
707 for( i = USER_STACK_SZ >> 12; i--; )
708 if( MM_GetPhysAddr( base + (i<<12) ) != 0 )
711 if(i != -1) return 0;
713 // Allocate Stack - Allocate incrementally to clean up MM_Dump output
714 for( i = 0; i < USER_STACK_SZ/0x1000; i++ )
716 if( !MM_Allocate( base + (i<<12) ) )
718 Warning("OOM: Proc_MakeUserStack");
723 return base + USER_STACK_SZ;
727 * \fn void Proc_StartUser(Uint Entrypoint, Uint *Bases, int ArgC, char **ArgV, char **EnvP, int DataSize)
728 * \brief Starts a user task
730 void Proc_StartUser(Uint Entrypoint, Uint *Bases, int ArgC, char **ArgV, char **EnvP, int DataSize)
732 Uint *stack = (void*)Proc_MakeUserStack();
737 //Log("stack = %p", stack);
740 stack -= DataSize/sizeof(*stack);
741 memcpy( stack, ArgV, DataSize );
743 //Log("stack = %p", stack);
747 // Adjust Arguments and environment
748 delta = (Uint)stack - (Uint)ArgV;
749 ArgV = (char**)stack;
750 for( i = 0; ArgV[i]; i++ )
754 // Do we care about EnvP?
757 for( i = 0; EnvP[i]; i++ )
762 // User Mode Segments
763 ss = 0x23; cs = 0x1B;
766 *--stack = (Uint)EnvP;
767 *--stack = (Uint)ArgV;
768 *--stack = (Uint)ArgC;
771 *--stack = 0; // Return Address
773 Proc_StartProcess(ss, (Uint)stack, 0x202, cs, Entrypoint);
776 void Proc_StartProcess(Uint16 SS, Uint Stack, Uint Flags, Uint16 CS, Uint IP)
778 Uint *stack = (void*)Stack;
779 *--stack = SS; //Stack Segment
780 *--stack = Stack; //Stack Pointer
781 *--stack = Flags; //EFLAGS (Resvd (0x2) and IF (0x20))
782 *--stack = CS; //Code Segment
785 *--stack = 0xAAAAAAAA; // eax
786 *--stack = 0xCCCCCCCC; // ecx
787 *--stack = 0xDDDDDDDD; // edx
788 *--stack = 0xBBBBBBBB; // ebx
789 *--stack = 0xD1D1D1D1; // edi
790 *--stack = 0x54545454; // esp - NOT POPED
791 *--stack = 0x51515151; // esi
792 *--stack = 0xB4B4B4B4; // ebp
799 __asm__ __volatile__ (
800 "mov %%eax,%%esp;\n\t" // Set stack pointer
806 "iret;\n\t" : : "a" (stack));
811 * \fn int Proc_Demote(Uint *Err, int Dest, tRegs *Regs)
812 * \brief Demotes a process to a lower permission level
813 * \param Err Pointer to user's errno
814 * \param Dest New Permission Level
815 * \param Regs Pointer to user's register structure
817 int Proc_Demote(Uint *Err, int Dest, tRegs *Regs)
819 int cpl = Regs->cs & 3;
821 if(Dest > 3 || Dest < 0) {
832 // Change the Segment Registers
833 Regs->cs = (((Dest+1)<<4) | Dest) - 8;
834 Regs->ss = ((Dest+1)<<4) | Dest;
835 // Check if the GP Segs are GDT, then change them
836 if(!(Regs->ds & 4)) Regs->ds = ((Dest+1)<<4) | Dest;
837 if(!(Regs->es & 4)) Regs->es = ((Dest+1)<<4) | Dest;
838 if(!(Regs->fs & 4)) Regs->fs = ((Dest+1)<<4) | Dest;
839 if(!(Regs->gs & 4)) Regs->gs = ((Dest+1)<<4) | Dest;
845 * \brief Calls a signal handler in user mode
846 * \note Used for signals
848 void Proc_CallFaultHandler(tThread *Thread)
850 // Rewinds the stack and calls the user function
852 Proc_ReturnToUser( Thread->FaultHandler, Thread->CurFaultNum, Thread->KernelStack );
856 void Proc_DumpThreadCPUState(tThread *Thread)
858 Uint32 *stack = (void *)Thread->SavedState.EBP; // EBP = ESP after call and PUSH
860 if( Thread->CurCPU > -1 )
862 Log(" Currently running");
867 tVAddr diffFromScheduler = Thread->SavedState.EIP - (tVAddr)Proc_Scheduler;
868 tVAddr diffFromClone = Thread->SavedState.EIP - (tVAddr)Proc_Clone;
869 tVAddr diffFromSpawn = Thread->SavedState.EIP - (tVAddr)Proc_SpawnWorker;
871 if( diffFromClone > 0 && diffFromClone < 512 ) // When I last checked, GetEIP was at .+0x183
873 // Just spawned full thread
874 Log(" Creating full thread");
878 if( diffFromSpawn > 0 && diffFromSpawn < 512 ) // When I last checked, GetEIP was at .+0x99
880 // Just spawned worker thread
881 Log(" Creating worker thread");
885 if( diffFromScheduler > 0 && diffFromScheduler < 256 ) // When I last checked, GetEIP was at .+0x60
887 if( stack[1] == (Uint32)&IRQCommon + 25 )
889 tRegs *regs = (void *) stack[2];
890 Log(" oldebp = 0x%08x, ret = 0x%08x, regs = 0x%x",
891 stack[0], stack[1], stack[2]
894 // [EBP+0x04] = Return Addr
895 // [EBP+0x08] = Arg 1 (CPU Number)
896 // [EBP+0x0C] = Arg 2 (Thread)
897 // [EBP+0x10] = GS (start of tRegs)
898 Log(" IRQ%i from %02x:%08x", regs->int_num regs->cs, regs->eip);
900 if( stack[1] == (Uint32)&scheduler_return )
904 tRegs *regs = (void *) &stack[4];
905 Log(" oldebp = 0x%08x, ret = 0x%08x, cpu = %i, thread = 0x%x",
906 stack[0], stack[1], stack[2], stack[3]);
908 // [EBP+0x04] = Return Addr
909 // [EBP+0x08] = Arg 1 (CPU Number)
910 // [EBP+0x0C] = Arg 2 (Thread)
911 // [EBP+0x10] = GS (start of tRegs)
912 Log(" At %02x:%08x", regs->cs, regs->eip);
916 Log(" Just created");
920 * \fn void Proc_Scheduler(int CPU)
921 * \brief Swap current thread and clears dead threads
923 void Proc_Scheduler(int CPU)
928 // If the spinlock is set, let it complete
929 if(IS_LOCKED(&glThreadListLock)) return;
931 // Get current thread
933 thread = gaCPUs[CPU].Current;
935 thread = gCurrentThread;
940 // Reduce remaining quantum and continue timeslice if non-zero
941 if( thread->Remaining-- )
943 // Reset quantum for next call
944 thread->Remaining = thread->Quantum;
947 __asm__ __volatile__ ( "mov %%esp, %0" : "=r" (esp) );
948 __asm__ __volatile__ ( "mov %%ebp, %0" : "=r" (ebp) );
950 if(eip == SWITCH_MAGIC) return; // Check if a switch happened
952 // Save machine state
953 thread->SavedState.ESP = esp;
954 thread->SavedState.EBP = ebp;
955 thread->SavedState.EIP = eip;
958 // Get next thread to run
959 thread = Threads_GetNextToRun(CPU, thread);
961 // No avaliable tasks, just go into low power mode (idle thread)
964 thread = gaCPUs[CPU].IdleThread;
965 Log("CPU %i Running Idle Thread", CPU);
967 thread = gpIdleThread;
971 // Set current thread
973 gaCPUs[CPU].Current = thread;
975 gCurrentThread = thread;
978 #if DEBUG_TRACE_SWITCH
979 Log("Switching to task %i, CR3 = 0x%x, EIP = %p",
981 thread->MemState.CR3,
982 thread->SavedState.EIP
986 #if USE_MP // MP Debug
987 // Log("CPU = %i, Thread %p", CPU, thread);
990 // Update Kernel Stack pointer
991 gTSSs[CPU].ESP0 = thread->KernelStack-4;
994 if(thread->SavedState.ESP > 0xC0000000
995 && thread->SavedState.ESP < thread->KernelStack-0x2000) {
996 Log_Warning("Proc", "Possible bad ESP %p (PID %i)", thread->SavedState.ESP);
1001 # error "Todo: Implement PAE Address space switching"
1004 __asm__ __volatile__ (
1005 "mov %4, %%cr3\n\t" // Set address space
1006 "mov %1, %%esp\n\t" // Restore ESP
1007 "mov %2, %%ebp\n\t" // and EBP
1008 "jmp *%3" : : // And return to where we saved state (Proc_Clone or Proc_Scheduler)
1009 "a"(SWITCH_MAGIC), "b"(thread->SavedState.ESP),
1010 "d"(thread->SavedState.EBP), "c"(thread->SavedState.EIP),
1011 "r"(thread->MemState.CR3)
1014 for(;;); // Shouldn't reach here
1018 EXPORT(Proc_SpawnWorker);