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
35 Uint8 State; // 0: Unavaliable, 1: Idle, 2: Active
45 extern void APWait(void); // 16-bit AP pause code
46 extern void APStartup(void); // 16-bit AP startup code
47 extern Uint GetEIP(void); // start.asm
48 extern Uint GetEIP_Sched(void); // proc.asm
49 extern void NewTaskHeader(tThread *Thread, void *Fcn, int nArgs, ...); // Actually takes cdecl args
50 extern Uint32 gaInitPageDir[1024]; // start.asm
51 extern char Kernel_Stack_Top[];
52 extern tShortSpinlock glThreadListLock;
55 extern tThread gThreadZero;
56 extern void Isr8(void); // Double Fault
57 extern void Proc_ReturnToUser(tVAddr Handler, Uint Argument, tVAddr KernelStack);
58 extern void scheduler_return; // Return address in SchedulerBase
59 extern void IRQCommon; // Common IRQ handler code
60 extern void IRQCommon_handled; // IRQCommon call return location
61 extern void GetEIP_Sched_ret; // GetEIP call return location
64 //void ArchThreads_Init(void);
66 void MP_StartAP(int CPU);
67 void MP_SendIPI(Uint8 APICID, int Vector, int DeliveryMode);
69 //void Proc_Start(void);
70 //tThread *Proc_GetCurThread(void);
71 void Proc_ChangeStack(void);
72 // int Proc_Clone(Uint *Err, Uint Flags);
73 Uint Proc_MakeUserStack(void);
74 //void Proc_StartUser(Uint Entrypoint, Uint *Bases, int ArgC, char **ArgV, char **EnvP, int DataSize);
75 void Proc_StartProcess(Uint16 SS, Uint Stack, Uint Flags, Uint16 CS, Uint IP);
76 int Proc_Demote(Uint *Err, int Dest, tRegs *Regs);
77 //void Proc_CallFaultHandler(tThread *Thread);
78 //void Proc_DumpThreadCPUState(tThread *Thread);
79 void Proc_Scheduler(int CPU);
82 // --- Multiprocessing ---
84 volatile int giNumInitingCPUs = 0;
85 tMPInfo *gMPFloatPtr = NULL;
86 volatile Uint32 giMP_TimerCount; // Start Count for Local APIC Timer
87 tAPIC *gpMP_LocalAPIC = NULL;
88 Uint8 gaAPIC_to_CPU[256] = {0};
89 tCPU gaCPUs[MAX_CPUS];
90 tTSS gaTSSs[MAX_CPUS]; // TSS Array
91 int giProc_BootProcessorID = 0;
93 tThread *gCurrentThread = NULL;
94 tThread *gpIdleThread = NULL;
96 tTSS *gTSSs = NULL; // Pointer to TSS array
98 // --- Error Recovery ---
99 char gaDoubleFaultStack[1024] __attribute__ ((section(".padata")));
100 tTSS gDoubleFault_TSS = {
101 .ESP0 = (Uint)&gaDoubleFaultStack[1024],
103 .CR3 = (Uint)gaInitPageDir - KERNEL_BASE,
105 .ESP = (Uint)&gaDoubleFaultStack[1024],
106 .CS = 0x08, .SS = 0x10,
107 .DS = 0x10, .ES = 0x10,
108 .FS = 0x10, .GS = 0x10,
113 * \fn void ArchThreads_Init(void)
114 * \brief Starts the process scheduler
116 void ArchThreads_Init(void)
123 // Mark BSP as active
126 // -- Initialise Multiprocessing
127 // Find MP Floating Table
128 // - EBDA/Last 1Kib (640KiB)
129 for(pos = KERNEL_BASE|0x9F000; pos < (KERNEL_BASE|0xA0000); pos += 16) {
130 if( *(Uint*)(pos) == MPPTR_IDENT ) {
131 Log("Possible %p", pos);
132 if( ByteSum((void*)pos, sizeof(tMPInfo)) != 0 ) continue;
133 gMPFloatPtr = (void*)pos;
137 // - Last KiB (512KiB base mem)
139 for(pos = KERNEL_BASE|0x7F000; pos < (KERNEL_BASE|0x80000); pos += 16) {
140 if( *(Uint*)(pos) == MPPTR_IDENT ) {
141 Log("Possible %p", pos);
142 if( ByteSum((void*)pos, sizeof(tMPInfo)) != 0 ) continue;
143 gMPFloatPtr = (void*)pos;
150 for(pos = KERNEL_BASE|0xE0000; pos < (KERNEL_BASE|0x100000); pos += 16) {
151 if( *(Uint*)(pos) == MPPTR_IDENT ) {
152 Log("Possible %p", pos);
153 if( ByteSum((void*)pos, sizeof(tMPInfo)) != 0 ) continue;
154 gMPFloatPtr = (void*)pos;
160 // If the MP Table Exists, parse it
165 Log("gMPFloatPtr = %p", gMPFloatPtr);
166 Log("*gMPFloatPtr = {");
167 Log("\t.Sig = 0x%08x", gMPFloatPtr->Sig);
168 Log("\t.MPConfig = 0x%08x", gMPFloatPtr->MPConfig);
169 Log("\t.Length = 0x%02x", gMPFloatPtr->Length);
170 Log("\t.Version = 0x%02x", gMPFloatPtr->Version);
171 Log("\t.Checksum = 0x%02x", gMPFloatPtr->Checksum);
172 Log("\t.Features = [0x%02x,0x%02x,0x%02x,0x%02x,0x%02x]",
173 gMPFloatPtr->Features[0], gMPFloatPtr->Features[1],
174 gMPFloatPtr->Features[2], gMPFloatPtr->Features[3],
175 gMPFloatPtr->Features[4]
179 mptable = (void*)( KERNEL_BASE|gMPFloatPtr->MPConfig );
180 Log("mptable = %p", mptable);
182 Log("\t.Sig = 0x%08x", mptable->Sig);
183 Log("\t.BaseTableLength = 0x%04x", mptable->BaseTableLength);
184 Log("\t.SpecRev = 0x%02x", mptable->SpecRev);
185 Log("\t.Checksum = 0x%02x", mptable->Checksum);
186 Log("\t.OEMID = '%8c'", mptable->OemID);
187 Log("\t.ProductID = '%8c'", mptable->ProductID);
188 Log("\t.OEMTablePtr = %p'", mptable->OEMTablePtr);
189 Log("\t.OEMTableSize = 0x%04x", mptable->OEMTableSize);
190 Log("\t.EntryCount = 0x%04x", mptable->EntryCount);
191 Log("\t.LocalAPICMemMap = 0x%08x", mptable->LocalAPICMemMap);
192 Log("\t.ExtendedTableLen = 0x%04x", mptable->ExtendedTableLen);
193 Log("\t.ExtendedTableChecksum = 0x%02x", mptable->ExtendedTableChecksum);
196 gpMP_LocalAPIC = (void*)MM_MapHWPages(mptable->LocalAPICMemMap, 1);
198 ents = mptable->Entries;
201 for( i = 0; i < mptable->EntryCount; i ++ )
208 Log("%i: Processor", i);
209 Log("\t.APICID = %i", ents->Proc.APICID);
210 Log("\t.APICVer = 0x%02x", ents->Proc.APICVer);
211 Log("\t.CPUFlags = 0x%02x", ents->Proc.CPUFlags);
212 Log("\t.CPUSignature = 0x%08x", ents->Proc.CPUSignature);
213 Log("\t.FeatureFlags = 0x%08x", ents->Proc.FeatureFlags);
216 if( !(ents->Proc.CPUFlags & 1) ) {
221 // Check if there is too many processors
222 if(giNumCPUs >= MAX_CPUS) {
223 giNumCPUs ++; // If `giNumCPUs` > MAX_CPUS later, it will be clipped
227 // Initialise CPU Info
228 gaAPIC_to_CPU[ents->Proc.APICID] = giNumCPUs;
229 gaCPUs[giNumCPUs].APICID = ents->Proc.APICID;
230 gaCPUs[giNumCPUs].State = 0;
234 if( ents->Proc.CPUFlags & 2 ) {
235 giProc_BootProcessorID = giNumCPUs-1;
244 Log("\t.ID = %i", ents->Bus.ID);
245 Log("\t.TypeString = '%6C'", ents->Bus.TypeString);
249 Log("%i: I/O APIC", i);
250 Log("\t.ID = %i", ents->IOAPIC.ID);
251 Log("\t.Version = 0x%02x", ents->IOAPIC.Version);
252 Log("\t.Flags = 0x%02x", ents->IOAPIC.Flags);
253 Log("\t.Addr = 0x%08x", ents->IOAPIC.Addr);
255 case 3: // I/O Interrupt Assignment
257 Log("%i: I/O Interrupt Assignment", i);
258 Log("\t.IntType = %i", ents->IOInt.IntType);
259 Log("\t.Flags = 0x%04x", ents->IOInt.Flags);
260 Log("\t.SourceBusID = 0x%02x", ents->IOInt.SourceBusID);
261 Log("\t.SourceBusIRQ = 0x%02x", ents->IOInt.SourceBusIRQ);
262 Log("\t.DestAPICID = 0x%02x", ents->IOInt.DestAPICID);
263 Log("\t.DestAPICIRQ = 0x%02x", ents->IOInt.DestAPICIRQ);
265 case 4: // Local Interrupt Assignment
267 Log("%i: Local Interrupt Assignment", i);
268 Log("\t.IntType = %i", ents->LocalInt.IntType);
269 Log("\t.Flags = 0x%04x", ents->LocalInt.Flags);
270 Log("\t.SourceBusID = 0x%02x", ents->LocalInt.SourceBusID);
271 Log("\t.SourceBusIRQ = 0x%02x", ents->LocalInt.SourceBusIRQ);
272 Log("\t.DestLocalAPICID = 0x%02x", ents->LocalInt.DestLocalAPICID);
273 Log("\t.DestLocalAPICIRQ = 0x%02x", ents->LocalInt.DestLocalAPICIRQ);
276 Log("%i: Unknown (%i)", i, ents->Type);
280 ents = (void*)( (Uint)ents + entSize );
283 if( giNumCPUs > MAX_CPUS ) {
284 Warning("Too many CPUs detected (%i), only using %i of them", giNumCPUs, MAX_CPUS);
285 giNumCPUs = MAX_CPUS;
290 Log("No MP Table was found, assuming uniprocessor\n");
299 #if !DEBUG_DISABLE_DOUBLEFAULT
300 // Initialise Double Fault TSS
301 gGDT[5].BaseLow = (Uint)&gDoubleFault_TSS & 0xFFFF;
302 gGDT[5].BaseMid = (Uint)&gDoubleFault_TSS >> 16;
303 gGDT[5].BaseHi = (Uint)&gDoubleFault_TSS >> 24;
305 // Set double fault IDT to use the new TSS
306 gIDT[8].OffsetLo = 0;
308 gIDT[8].Flags = 0x8500;
309 gIDT[8].OffsetHi = 0;
312 // Set timer frequency
313 outb(0x43, 0x34); // Set Channel 0, Low/High, Rate Generator
314 outb(0x40, TIMER_DIVISOR&0xFF); // Low Byte of Divisor
315 outb(0x40, (TIMER_DIVISOR>>8)&0xFF); // High Byte
317 Log("Timer Frequency %i.%03i Hz",
318 TIMER_BASE/TIMER_DIVISOR,
319 ((Uint64)TIMER_BASE*1000/TIMER_DIVISOR)%1000
323 // Get the count setting for APIC timer
324 Log("Determining APIC Count");
325 __asm__ __volatile__ ("sti");
326 while( giMP_TimerCount == 0 ) __asm__ __volatile__ ("hlt");
327 __asm__ __volatile__ ("cli");
328 Log("APIC Count %i", giMP_TimerCount);
330 Uint64 freq = giMP_TimerCount;
331 freq /= TIMER_DIVISOR;
333 if( (freq /= 1000) < 2*1000)
334 Log("Bus Frequency %i KHz", freq);
335 else if( (freq /= 1000) < 2*1000)
336 Log("Bus Frequency %i MHz", freq);
337 else if( (freq /= 1000) < 2*1000)
338 Log("Bus Frequency %i GHz", freq);
340 Log("Bus Frequency %i THz", freq);
343 // Initialise Normal TSS(s)
344 for(pos=0;pos<giNumCPUs;pos++)
349 gTSSs[pos].SS0 = 0x10;
350 gTSSs[pos].ESP0 = 0; // Set properly by scheduler
351 gGDT[6+pos].BaseLow = ((Uint)(&gTSSs[pos])) & 0xFFFF;
352 gGDT[6+pos].BaseMid = ((Uint)(&gTSSs[pos]) >> 16) & 0xFFFF;
353 gGDT[6+pos].BaseHi = ((Uint)(&gTSSs[pos])) >> 24;
358 // Load the BSP's TSS
359 __asm__ __volatile__ ("ltr %%ax"::"a"(0x30));
360 // Set Current Thread and CPU Number in DR0 and DR1
361 __asm__ __volatile__ ("mov %0, %%db0"::"r"(&gThreadZero));
362 __asm__ __volatile__ ("mov %0, %%db1"::"r"(0));
365 gaCPUs[0].Current = &gThreadZero;
367 gCurrentThread = &gThreadZero;
369 gThreadZero.CurCPU = 0;
371 gThreadZero.MemState.CR3 = (Uint)gaInitPageDir - KERNEL_BASE;
373 // Create Per-Process Data Block
374 if( !MM_Allocate(MM_PPD_CFG) )
376 Panic("OOM - No space for initial Per-Process Config");
384 void MP_StartAP(int CPU)
386 Log("Starting AP %i (APIC %i)", CPU, gaCPUs[CPU].APICID);
388 // Set location of AP startup code and mark for a warm restart
389 *(Uint16*)(KERNEL_BASE|0x467) = (Uint)&APWait - (KERNEL_BASE|0xFFFF0);
390 *(Uint16*)(KERNEL_BASE|0x469) = 0xFFFF;
391 outb(0x70, 0x0F); outb(0x71, 0x0A); // Set warm reset flag
392 MP_SendIPI(gaCPUs[CPU].APICID, 0, 5); // Init IPI
395 inb(0x80); inb(0x80); inb(0x80); inb(0x80);
397 // TODO: Use a better address, preferably registered with the MM
398 // - MM_AllocDMA mabye?
400 *(Uint8*)(KERNEL_BASE|0x11000) = 0xEA; // Far JMP
401 *(Uint16*)(KERNEL_BASE|0x11001) = (Uint)&APStartup - (KERNEL_BASE|0xFFFF0); // IP
402 *(Uint16*)(KERNEL_BASE|0x11003) = 0xFFFF; // CS
403 // Send a Startup-IPI to make the CPU execute at 0x11000 (which we
405 MP_SendIPI(gaCPUs[CPU].APICID, 0x11, 6); // StartupIPI
411 * \brief Send an Inter-Processor Interrupt
412 * \param APICID Processor's Local APIC ID
413 * \param Vector Argument of some kind
414 * \param DeliveryMode Type of signal?
416 void MP_SendIPI(Uint8 APICID, int Vector, int DeliveryMode)
421 val = (Uint)APICID << 24;
422 Log("*%p = 0x%08x", &gpMP_LocalAPIC->ICR[1], val);
423 gpMP_LocalAPIC->ICR[1].Val = val;
425 val = ((DeliveryMode & 7) << 8) | (Vector & 0xFF);
426 Log("*%p = 0x%08x", &gpMP_LocalAPIC->ICR[0], val);
427 gpMP_LocalAPIC->ICR[0].Val = val;
432 * \fn void Proc_Start(void)
433 * \brief Start process scheduler
435 void Proc_Start(void)
443 for( i = 0; i < giNumCPUs; i ++ )
446 if(i) gaCPUs[i].Current = NULL;
449 if( (tid = Proc_Clone(0, 0)) == 0)
451 for(;;) HALT(); // Just yeilds
453 gaCPUs[i].IdleThread = Threads_GetThread(tid);
454 gaCPUs[i].IdleThread->ThreadName = (char*)"Idle Thread";
455 Threads_SetPriority( gaCPUs[i].IdleThread, -1 ); // Never called randomly
456 gaCPUs[i].IdleThread->Quantum = 1; // 1 slice quantum
460 if( i != giProc_BootProcessorID ) {
465 // BSP still should run the current task
466 gaCPUs[0].Current = &gThreadZero;
468 // Start interrupts and wait for APs to come up
469 Log("Waiting for APs to come up\n");
470 __asm__ __volatile__ ("sti");
471 while( giNumInitingCPUs ) __asm__ __volatile__ ("hlt");
474 if(Proc_Clone(0) == 0)
476 gpIdleThread = Proc_GetCurThread();
477 gpIdleThread->ThreadName = strdup("Idle Thread");
478 Threads_SetPriority( gpIdleThread, -1 ); // Never called randomly
479 gpIdleThread->Quantum = 1; // 1 slice quantum
480 for(;;) HALT(); // Just yeilds
484 gCurrentThread = &gThreadZero;
486 // Start Interrupts (and hence scheduler)
487 __asm__ __volatile__("sti");
489 MM_FinishVirtualInit();
493 * \fn tThread *Proc_GetCurThread(void)
494 * \brief Gets the current thread
496 tThread *Proc_GetCurThread(void)
499 return gaCPUs[ GetCPUNum() ].Current;
501 return gCurrentThread;
506 * \fn void Proc_ChangeStack(void)
507 * \brief Swaps the current stack for a new one (in the proper stack reigon)
509 void Proc_ChangeStack(void)
513 Uint curBase, newBase;
515 __asm__ __volatile__ ("mov %%esp, %0":"=r"(esp));
516 __asm__ __volatile__ ("mov %%ebp, %0":"=r"(ebp));
521 newBase = MM_NewKStack();
524 Panic("What the?? Unable to allocate space for initial kernel stack");
528 curBase = (Uint)&Kernel_Stack_Top;
530 LOG("curBase = 0x%x, newBase = 0x%x", curBase, newBase);
532 // Get ESP as a used size
534 LOG("memcpy( %p, %p, 0x%x )", (void*)(newBase - esp), (void*)(curBase - esp), esp );
536 memcpy( (void*)(newBase - esp), (void*)(curBase - esp), esp );
537 // Get ESP as an offset in the new stack
540 ebp = newBase - (curBase - ebp);
542 // Repair EBPs & Stack Addresses
543 // Catches arguments also, but may trash stack-address-like values
544 for(tmpEbp = esp; tmpEbp < newBase; tmpEbp += 4)
546 if(oldEsp < *(Uint*)tmpEbp && *(Uint*)tmpEbp < curBase)
547 *(Uint*)tmpEbp += newBase - curBase;
550 Proc_GetCurThread()->KernelStack = newBase;
552 __asm__ __volatile__ ("mov %0, %%esp"::"r"(esp));
553 __asm__ __volatile__ ("mov %0, %%ebp"::"r"(ebp));
557 * \fn int Proc_Clone(Uint *Err, Uint Flags)
558 * \brief Clone the current process
560 int Proc_Clone(Uint Flags)
563 tThread *cur = Proc_GetCurThread();
566 __asm__ __volatile__ ("mov %%esp, %0": "=r"(esp));
567 __asm__ __volatile__ ("mov %%ebp, %0": "=r"(ebp));
569 newThread = Threads_CloneTCB(NULL, Flags);
570 if(!newThread) return -1;
572 // Initialise Memory Space (New Addr space or kernel stack)
573 if(Flags & CLONE_VM) {
574 newThread->MemState.CR3 = MM_Clone();
576 if(newThread->MemState.CR3 == 0) {
577 Threads_Kill(newThread, -2);
580 newThread->KernelStack = cur->KernelStack;
582 Uint tmpEbp, oldEsp = esp;
585 newThread->MemState.CR3 = cur->MemState.CR3;
588 newThread->KernelStack = MM_NewKStack();
590 if(newThread->KernelStack == 0) {
591 Threads_Kill(newThread, -2);
595 // Get ESP as a used size
596 esp = cur->KernelStack - esp;
598 memcpy( (void*)(newThread->KernelStack - esp), (void*)(cur->KernelStack - esp), esp );
599 // Get ESP as an offset in the new stack
600 esp = newThread->KernelStack - esp;
602 ebp = newThread->KernelStack - (cur->KernelStack - ebp);
604 // Repair EBPs & Stack Addresses
605 // Catches arguments also, but may trash stack-address-like values
606 for(tmpEbp = esp; tmpEbp < newThread->KernelStack; tmpEbp += 4)
608 if(oldEsp < *(Uint*)tmpEbp && *(Uint*)tmpEbp < cur->KernelStack)
609 *(Uint*)tmpEbp += newThread->KernelStack - cur->KernelStack;
613 // Save core machine state
614 newThread->SavedState.ESP = esp;
615 newThread->SavedState.EBP = ebp;
618 //__asm__ __volatile__ ("mov %0, %%db0" : : "r" (newThread) );
622 gpMP_LocalAPIC->EOI.Val = 0;
625 outb(0x20, 0x20); // ACK Timer and return as child
626 __asm__ __volatile__ ("sti"); // Restart interrupts
631 newThread->SavedState.EIP = eip;
633 // Lock list and add to active
634 Threads_AddActive(newThread);
636 return newThread->TID;
640 * \fn int Proc_SpawnWorker(void)
641 * \brief Spawns a new worker thread
643 int Proc_SpawnWorker(void (*Fcn)(void*), void *Data)
646 Uint stack_contents[4];
649 new = Threads_CloneThreadZero();
651 Warning("Proc_SpawnWorker - Out of heap space!\n");
655 // Create the stack contents
656 stack_contents[3] = (Uint)Data;
657 stack_contents[2] = 1;
658 stack_contents[1] = (Uint)Fcn;
659 stack_contents[0] = (Uint)new;
661 // Create a new worker stack (in PID0's address space)
662 new->KernelStack = MM_NewWorkerStack(stack_contents, sizeof(stack_contents));
664 // Save core machine state
665 new->SavedState.ESP = new->KernelStack - sizeof(stack_contents);
666 new->SavedState.EBP = 0;
667 new->SavedState.EIP = (Uint)NewTaskHeader;
670 new->Status = THREAD_STAT_PREINIT;
671 Threads_AddActive( new );
677 * \fn Uint Proc_MakeUserStack(void)
678 * \brief Creates a new user stack
680 Uint Proc_MakeUserStack(void)
683 Uint base = USER_STACK_TOP - USER_STACK_SZ;
685 // Check Prospective Space
686 for( i = USER_STACK_SZ >> 12; i--; )
687 if( MM_GetPhysAddr( base + (i<<12) ) != 0 )
690 if(i != -1) return 0;
692 // Allocate Stack - Allocate incrementally to clean up MM_Dump output
693 for( i = 0; i < USER_STACK_SZ/0x1000; i++ )
695 if( !MM_Allocate( base + (i<<12) ) )
697 Warning("OOM: Proc_MakeUserStack");
702 return base + USER_STACK_SZ;
706 * \fn void Proc_StartUser(Uint Entrypoint, Uint *Bases, int ArgC, char **ArgV, char **EnvP, int DataSize)
707 * \brief Starts a user task
709 void Proc_StartUser(Uint Entrypoint, Uint *Bases, int ArgC, char **ArgV, char **EnvP, int DataSize)
711 Uint *stack = (void*)Proc_MakeUserStack();
716 //Log("stack = %p", stack);
719 stack -= DataSize/sizeof(*stack);
720 memcpy( stack, ArgV, DataSize );
722 //Log("stack = %p", stack);
726 // Adjust Arguments and environment
727 delta = (Uint)stack - (Uint)ArgV;
728 ArgV = (char**)stack;
729 for( i = 0; ArgV[i]; i++ )
733 // Do we care about EnvP?
736 for( i = 0; EnvP[i]; i++ )
741 // User Mode Segments
742 ss = 0x23; cs = 0x1B;
745 *--stack = (Uint)EnvP;
746 *--stack = (Uint)ArgV;
747 *--stack = (Uint)ArgC;
750 *--stack = 0; // Return Address
752 Proc_StartProcess(ss, (Uint)stack, 0x202, cs, Entrypoint);
755 void Proc_StartProcess(Uint16 SS, Uint Stack, Uint Flags, Uint16 CS, Uint IP)
757 Uint *stack = (void*)Stack;
758 *--stack = SS; //Stack Segment
759 *--stack = Stack; //Stack Pointer
760 *--stack = Flags; //EFLAGS (Resvd (0x2) and IF (0x20))
761 *--stack = CS; //Code Segment
764 *--stack = 0xAAAAAAAA; // eax
765 *--stack = 0xCCCCCCCC; // ecx
766 *--stack = 0xDDDDDDDD; // edx
767 *--stack = 0xBBBBBBBB; // ebx
768 *--stack = 0xD1D1D1D1; // edi
769 *--stack = 0x54545454; // esp - NOT POPED
770 *--stack = 0x51515151; // esi
771 *--stack = 0xB4B4B4B4; // ebp
778 __asm__ __volatile__ (
779 "mov %%eax,%%esp;\n\t" // Set stack pointer
785 "iret;\n\t" : : "a" (stack));
790 * \fn int Proc_Demote(Uint *Err, int Dest, tRegs *Regs)
791 * \brief Demotes a process to a lower permission level
792 * \param Err Pointer to user's errno
793 * \param Dest New Permission Level
794 * \param Regs Pointer to user's register structure
796 int Proc_Demote(Uint *Err, int Dest, tRegs *Regs)
798 int cpl = Regs->cs & 3;
800 if(Dest > 3 || Dest < 0) {
811 // Change the Segment Registers
812 Regs->cs = (((Dest+1)<<4) | Dest) - 8;
813 Regs->ss = ((Dest+1)<<4) | Dest;
814 // Check if the GP Segs are GDT, then change them
815 if(!(Regs->ds & 4)) Regs->ds = ((Dest+1)<<4) | Dest;
816 if(!(Regs->es & 4)) Regs->es = ((Dest+1)<<4) | Dest;
817 if(!(Regs->fs & 4)) Regs->fs = ((Dest+1)<<4) | Dest;
818 if(!(Regs->gs & 4)) Regs->gs = ((Dest+1)<<4) | Dest;
824 * \brief Calls a signal handler in user mode
825 * \note Used for signals
827 void Proc_CallFaultHandler(tThread *Thread)
829 // Rewinds the stack and calls the user function
831 Proc_ReturnToUser( Thread->FaultHandler, Thread->CurFaultNum, Thread->KernelStack );
835 void Proc_DumpThreadCPUState(tThread *Thread)
837 if( Thread->CurCPU > -1 )
839 int maxBacktraceDistance = 6;
843 if( Thread->CurCPU != GetCPUNum() ) {
844 Log(" Currently running");
848 // Backtrace to find the IRQ entrypoint
849 // - This will usually only be called by an IRQ, so this should
851 __asm__ __volatile__ ("mov %%ebp, %0" : "=r" (stack));
852 while( maxBacktraceDistance -- )
857 if( stack[1] == (tVAddr)&IRQCommon_handled ) {
858 regs = (void*)stack[2];
862 stack = (void*)stack[0];
866 Log(" Unable to find IRQ Entry");
870 Log(" at %04x:%08x", regs->cs, regs->eip);
875 tVAddr diffFromScheduler = Thread->SavedState.EIP - (tVAddr)Proc_Scheduler;
876 tVAddr diffFromClone = Thread->SavedState.EIP - (tVAddr)Proc_Clone;
877 tVAddr diffFromSpawn = Thread->SavedState.EIP - (tVAddr)Proc_SpawnWorker;
879 if( diffFromClone > 0 && diffFromClone < 512 ) // When I last checked, GetEIP was at .+0x183
881 Log(" Creating full thread");
885 if( diffFromSpawn > 0 && diffFromSpawn < 512 ) // When I last checked, GetEIP was at .+0x99
887 Log(" Creating worker thread");
891 if( diffFromScheduler > 0 && diffFromScheduler < 256 ) // When I last checked, GetEIP was at .+0x60
894 MM_ReadFromAddrSpace(Thread->MemState.CR3, Thread->SavedState.EBP, data, 12);
895 if( data[1] == (Uint32)&IRQCommon + 25 )
897 tRegs *regs = (void *) data[2];
898 Log(" oldebp = 0x%08x, ret = 0x%08x, regs = 0x%x",
899 data[0], data[1], data[2]
902 // [EBP+0x04] = Return Addr
903 // [EBP+0x08] = Arg 1 (CPU Number)
904 // [EBP+0x0C] = Arg 2 (Thread)
905 // [EBP+0x10] = GS (start of tRegs)
906 Log(" IRQ%i from %02x:%08x", regs->int_num regs->cs, regs->eip);
908 if( stack[1] == (Uint32)&scheduler_return )
912 Log(" At %04x:%08x", Thread->SavedState.UserCS, Thread->SavedState.UserEIP);
916 Log(" Just created (unknow %p)", Thread->SavedState.EIP);
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;
941 // Reduce remaining quantum and continue timeslice if non-zero
942 if( thread->Remaining-- )
944 // Reset quantum for next call
945 thread->Remaining = thread->Quantum;
948 __asm__ __volatile__ ( "mov %%esp, %0" : "=r" (esp) );
949 __asm__ __volatile__ ( "mov %%ebp, %0" : "=r" (ebp) );
952 __asm__ __volatile__ ( "nop" : : : "eax","ebx","ecx","edx","edi","esi");
953 regs = (tRegs*)(ebp+(2+2)*4); // EBP,Ret + CPU,CurThread
955 thread = gaCPUs[CPU].Current;
957 thread = gCurrentThread;
959 if(thread->bInstrTrace) {
960 regs->eflags |= 0x100; // Set TF
961 // LogF("Tracing enabled\n");
962 Log("%p Scheduled (EIP = %p)", thread, thread->SavedState.EIP);
965 regs->eflags &= ~0x100;
967 return; // Check if a switch happened
970 // Save machine state
971 thread->SavedState.ESP = esp;
972 thread->SavedState.EBP = ebp;
973 thread->SavedState.EIP = eip;
975 // TODO: Make this more stable somehow
976 regs = (tRegs*)(ebp+(2+2)*4); // EBP,Ret + CPU,CurThread
977 thread->SavedState.UserCS = regs->cs;
978 thread->SavedState.UserEIP = regs->eip;
980 if(thread->bInstrTrace) {
981 regs->eflags |= 0x100; // Set TF
982 Log("%p De-scheduled", thread);
985 regs->eflags &= ~0x100; // Clear TF
988 // Get next thread to run
989 thread = Threads_GetNextToRun(CPU, thread);
992 // No avaliable tasks, just go into low power mode (idle thread)
995 thread = gaCPUs[CPU].IdleThread;
996 Log("CPU %i Running Idle Thread", CPU);
998 thread = gpIdleThread;
1002 #if DEBUG_TRACE_SWITCH
1003 if(thread && thread != Proc_GetCurThread() ) {
1004 Log("Switching to task %i(%s), CR3 = 0x%x, EIP = %p",
1007 thread->MemState.CR3,
1008 thread->SavedState.EIP
1013 // Set current thread
1015 gaCPUs[CPU].Current = thread;
1017 gCurrentThread = thread;
1020 #if USE_MP // MP Debug
1021 // Log("CPU = %i, Thread %p", CPU, thread);
1024 // Update Kernel Stack pointer
1025 gTSSs[CPU].ESP0 = thread->KernelStack-4;
1028 if(thread->SavedState.ESP > 0xC0000000
1029 && thread->SavedState.ESP < thread->KernelStack-0x2000) {
1030 Log_Warning("Proc", "Possible bad ESP %p (PID %i)", thread->SavedState.ESP);
1034 if( thread->bInstrTrace ) {
1035 Log("%p Scheduled (EIP = %p)", thread, thread->SavedState.EIP);
1038 // Set thread pointer
1039 __asm__ __volatile__("mov %0, %%db0\n\t" : : "r"(thread) );
1041 __asm__ __volatile__ (
1042 "mov %3, %%cr3\n\t" // Set address space
1043 "mov %0, %%esp\n\t" // Restore ESP
1044 "mov %1, %%ebp\n\t" // and EBP
1047 "or %4, 72(%%ebp)\n\t" // or trace flag to eflags (2+2+4+8+2)*4
1049 "xor %%eax, %%eax\n\t"
1050 "jmp *%2" : : // And return to where we saved state (Proc_Clone or Proc_Scheduler)
1051 "r"(thread->SavedState.ESP),
1052 "r"(thread->SavedState.EBP),
1053 "r"(thread->SavedState.EIP),
1054 "r"(thread->MemState.CR3),
1055 "r"(thread->bInstrTrace&&thread->SavedState.EIP==(Uint)&GetEIP_Sched_ret?0x100:0)
1057 for(;;); // Shouldn't reach here
1061 EXPORT(Proc_SpawnWorker);