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, Uint *CR3);
49 extern Uint32 gaInitPageDir[1024]; // start.asm
50 extern char Kernel_Stack_Top[];
51 extern tShortSpinlock glThreadListLock;
54 extern tThread gThreadZero;
55 extern void Isr8(void); // Double Fault
56 extern void Proc_ReturnToUser(tVAddr Handler, Uint Argument, tVAddr KernelStack);
57 extern void scheduler_return; // Return address in SchedulerBase
58 extern void IRQCommon; // Common IRQ handler code
59 extern void IRQCommon_handled; // IRQCommon call return location
60 extern void GetEIP_Sched_ret; // GetEIP call return location
61 extern void Threads_AddToDelete(tThread *Thread);
62 extern void SwitchTasks(Uint NewSP, Uint *OldSP, Uint NewIP, Uint *OldIO, Uint CR3);
65 //void ArchThreads_Init(void);
67 void MP_StartAP(int CPU);
68 void MP_SendIPI(Uint8 APICID, int Vector, int DeliveryMode);
70 void Proc_IdleThread(void *Ptr);
71 //void Proc_Start(void);
72 //tThread *Proc_GetCurThread(void);
73 void Proc_ChangeStack(void);
74 int Proc_NewKThread(void (*Fcn)(void*), void *Data);
75 // int Proc_Clone(Uint *Err, Uint Flags);
76 Uint Proc_MakeUserStack(void);
77 //void Proc_StartUser(Uint Entrypoint, Uint *Bases, int ArgC, char **ArgV, char **EnvP, int DataSize);
78 void Proc_StartProcess(Uint16 SS, Uint Stack, Uint Flags, Uint16 CS, Uint IP);
79 int Proc_Demote(Uint *Err, int Dest, tRegs *Regs);
80 //void Proc_CallFaultHandler(tThread *Thread);
81 //void Proc_DumpThreadCPUState(tThread *Thread);
82 void Proc_Scheduler(int CPU);
85 // --- Multiprocessing ---
87 volatile int giNumInitingCPUs = 0;
88 tMPInfo *gMPFloatPtr = NULL;
89 volatile Uint32 giMP_TimerCount; // Start Count for Local APIC Timer
90 tAPIC *gpMP_LocalAPIC = NULL;
91 Uint8 gaAPIC_to_CPU[256] = {0};
92 int giProc_BootProcessorID = 0;
93 tTSS gaTSSs[MAX_CPUS]; // TSS Array
95 tCPU gaCPUs[MAX_CPUS];
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));
364 gaCPUs[0].Current = &gThreadZero;
365 gThreadZero.CurCPU = 0;
367 gThreadZero.MemState.CR3 = (Uint)gaInitPageDir - KERNEL_BASE;
369 // Create Per-Process Data Block
370 if( !MM_Allocate(MM_PPD_CFG) )
372 Panic("OOM - No space for initial Per-Process Config");
380 void MP_StartAP(int CPU)
382 Log("Starting AP %i (APIC %i)", CPU, gaCPUs[CPU].APICID);
384 // Set location of AP startup code and mark for a warm restart
385 *(Uint16*)(KERNEL_BASE|0x467) = (Uint)&APWait - (KERNEL_BASE|0xFFFF0);
386 *(Uint16*)(KERNEL_BASE|0x469) = 0xFFFF;
387 outb(0x70, 0x0F); outb(0x71, 0x0A); // Set warm reset flag
388 MP_SendIPI(gaCPUs[CPU].APICID, 0, 5); // Init IPI
391 inb(0x80); inb(0x80); inb(0x80); inb(0x80);
393 // TODO: Use a better address, preferably registered with the MM
394 // - MM_AllocDMA mabye?
396 *(Uint8*)(KERNEL_BASE|0x11000) = 0xEA; // Far JMP
397 *(Uint16*)(KERNEL_BASE|0x11001) = (Uint)&APStartup - (KERNEL_BASE|0xFFFF0); // IP
398 *(Uint16*)(KERNEL_BASE|0x11003) = 0xFFFF; // CS
399 // Send a Startup-IPI to make the CPU execute at 0x11000 (which we
401 MP_SendIPI(gaCPUs[CPU].APICID, 0x11, 6); // StartupIPI
407 * \brief Send an Inter-Processor Interrupt
408 * \param APICID Processor's Local APIC ID
409 * \param Vector Argument of some kind
410 * \param DeliveryMode Type of signal?
412 void MP_SendIPI(Uint8 APICID, int Vector, int DeliveryMode)
417 val = (Uint)APICID << 24;
418 Log("*%p = 0x%08x", &gpMP_LocalAPIC->ICR[1], val);
419 gpMP_LocalAPIC->ICR[1].Val = val;
421 val = ((DeliveryMode & 7) << 8) | (Vector & 0xFF);
422 Log("*%p = 0x%08x", &gpMP_LocalAPIC->ICR[0], val);
423 gpMP_LocalAPIC->ICR[0].Val = val;
427 void Proc_IdleThread(void *Ptr)
430 cpu->IdleThread->ThreadName = strdup("Idle Thread");
431 Threads_SetPriority( cpu->IdleThread, -1 ); // Never called randomly
432 cpu->IdleThread->Quantum = 1; // 1 slice quantum
440 * \fn void Proc_Start(void)
441 * \brief Start process scheduler
443 void Proc_Start(void)
452 for( i = 0; i < giNumCPUs; i ++ )
454 if(i) gaCPUs[i].Current = NULL;
457 tid = Proc_NewKThread(Proc_IdleThread, &gaCPUs[i]);
458 gaCPUs[i].IdleThread = Threads_GetThread(tid);
461 if( i != giProc_BootProcessorID ) {
466 // BSP still should run the current task
467 gaCPUs[0].Current = &gThreadZero;
469 // Start interrupts and wait for APs to come up
470 Log("Waiting for APs to come up\n");
471 __asm__ __volatile__ ("sti");
472 while( giNumInitingCPUs ) __asm__ __volatile__ ("hlt");
475 tid = Proc_NewKThread(Proc_IdleThread, &gaCPUs[0]);
476 gaCPUs[0].IdleThread = Threads_GetThread(tid);
479 gaCPUs[0].Current = &gThreadZero;
481 // while( gaCPUs[0].IdleThread == NULL )
484 // Start Interrupts (and hence scheduler)
485 __asm__ __volatile__("sti");
487 MM_FinishVirtualInit();
491 * \fn tThread *Proc_GetCurThread(void)
492 * \brief Gets the current thread
494 tThread *Proc_GetCurThread(void)
497 return gaCPUs[ GetCPUNum() ].Current;
499 return gaCPUs[ 0 ].Current;
504 * \fn void Proc_ChangeStack(void)
505 * \brief Swaps the current stack for a new one (in the proper stack reigon)
507 void Proc_ChangeStack(void)
511 Uint curBase, newBase;
513 __asm__ __volatile__ ("mov %%esp, %0":"=r"(esp));
514 __asm__ __volatile__ ("mov %%ebp, %0":"=r"(ebp));
519 newBase = MM_NewKStack();
522 Panic("What the?? Unable to allocate space for initial kernel stack");
526 curBase = (Uint)&Kernel_Stack_Top;
528 LOG("curBase = 0x%x, newBase = 0x%x", curBase, newBase);
530 // Get ESP as a used size
532 LOG("memcpy( %p, %p, 0x%x )", (void*)(newBase - esp), (void*)(curBase - esp), esp );
534 memcpy( (void*)(newBase - esp), (void*)(curBase - esp), esp );
535 // Get ESP as an offset in the new stack
538 ebp = newBase - (curBase - ebp);
540 // Repair EBPs & Stack Addresses
541 // Catches arguments also, but may trash stack-address-like values
542 for(tmpEbp = esp; tmpEbp < newBase; tmpEbp += 4)
544 if(oldEsp < *(Uint*)tmpEbp && *(Uint*)tmpEbp < curBase)
545 *(Uint*)tmpEbp += newBase - curBase;
548 Proc_GetCurThread()->KernelStack = newBase;
550 __asm__ __volatile__ ("mov %0, %%esp"::"r"(esp));
551 __asm__ __volatile__ ("mov %0, %%ebp"::"r"(ebp));
554 int Proc_NewKThread(void (*Fcn)(void*), void *Data)
557 tThread *newThread, *cur;
559 cur = Proc_GetCurThread();
560 newThread = Threads_CloneTCB(NULL, 0);
561 if(!newThread) return -1;
564 newThread->MemState.CR3 = cur->MemState.CR3;
567 newThread->KernelStack = MM_NewKStack();
569 if(newThread->KernelStack == 0) {
574 esp = newThread->KernelStack;
575 *(Uint*)(esp-=4) = (Uint)Data; // Data (shadowed)
576 *(Uint*)(esp-=4) = 1; // Number of params
577 *(Uint*)(esp-=4) = (Uint)Fcn; // Function to call
578 *(Uint*)(esp-=4) = (Uint)newThread; // Thread ID
580 newThread->SavedState.ESP = esp;
581 newThread->SavedState.EIP = (Uint)&NewTaskHeader;
582 Log("New (KThread) %p, esp = %p\n", newThread->SavedState.EIP, newThread->SavedState.ESP);
585 Threads_AddActive(newThread);
587 return newThread->TID;
591 * \fn int Proc_Clone(Uint *Err, Uint Flags)
592 * \brief Clone the current process
594 int Proc_Clone(Uint Flags)
597 tThread *cur = Proc_GetCurThread();
601 if( !(Flags & CLONE_VM) ) {
602 Log_Error("Proc", "Proc_Clone: Don't leave CLONE_VM unset, use Proc_NewKThread instead");
607 newThread = Threads_CloneTCB(NULL, Flags);
608 if(!newThread) return -1;
610 newThread->KernelStack = cur->KernelStack;
613 eip = Proc_CloneInt(&newThread->SavedState.ESP, &newThread->MemState.CR3);
618 newThread->SavedState.EIP = eip;
621 if( newThread->MemState.CR3 == 0 ) {
622 Log_Error("Proc", "Proc_Clone: MM_Clone failed");
623 Threads_AddToDelete(newThread);
627 // Add the new thread to the run queue
628 Threads_AddActive(newThread);
629 return newThread->TID;
633 * \fn int Proc_SpawnWorker(void)
634 * \brief Spawns a new worker thread
636 int Proc_SpawnWorker(void (*Fcn)(void*), void *Data)
639 Uint stack_contents[4];
642 new = Threads_CloneThreadZero();
644 Warning("Proc_SpawnWorker - Out of heap space!\n");
648 // Create the stack contents
649 stack_contents[3] = (Uint)Data;
650 stack_contents[2] = 1;
651 stack_contents[1] = (Uint)Fcn;
652 stack_contents[0] = (Uint)new;
654 // Create a new worker stack (in PID0's address space)
655 new->KernelStack = MM_NewWorkerStack(stack_contents, sizeof(stack_contents));
657 // Save core machine state
658 new->SavedState.ESP = new->KernelStack - sizeof(stack_contents);
659 new->SavedState.EBP = 0;
660 new->SavedState.EIP = (Uint)NewTaskHeader;
663 new->Status = THREAD_STAT_PREINIT;
664 Threads_AddActive( new );
670 * \fn Uint Proc_MakeUserStack(void)
671 * \brief Creates a new user stack
673 Uint Proc_MakeUserStack(void)
676 Uint base = USER_STACK_TOP - USER_STACK_SZ;
678 // Check Prospective Space
679 for( i = USER_STACK_SZ >> 12; i--; )
680 if( MM_GetPhysAddr( base + (i<<12) ) != 0 )
683 if(i != -1) return 0;
685 // Allocate Stack - Allocate incrementally to clean up MM_Dump output
686 for( i = 0; i < USER_STACK_SZ/0x1000; i++ )
688 if( !MM_Allocate( base + (i<<12) ) )
690 Warning("OOM: Proc_MakeUserStack");
695 return base + USER_STACK_SZ;
699 * \fn void Proc_StartUser(Uint Entrypoint, Uint *Bases, int ArgC, char **ArgV, char **EnvP, int DataSize)
700 * \brief Starts a user task
702 void Proc_StartUser(Uint Entrypoint, Uint *Bases, int ArgC, char **ArgV, char **EnvP, int DataSize)
704 Uint *stack = (void*)Proc_MakeUserStack();
709 //Log("stack = %p", stack);
712 stack -= DataSize/sizeof(*stack);
713 memcpy( stack, ArgV, DataSize );
715 //Log("stack = %p", stack);
719 // Adjust Arguments and environment
720 delta = (Uint)stack - (Uint)ArgV;
721 ArgV = (char**)stack;
722 for( i = 0; ArgV[i]; i++ )
726 // Do we care about EnvP?
729 for( i = 0; EnvP[i]; i++ )
734 // User Mode Segments
735 ss = 0x23; cs = 0x1B;
738 *--stack = (Uint)EnvP;
739 *--stack = (Uint)ArgV;
740 *--stack = (Uint)ArgC;
743 *--stack = 0; // Return Address
745 Proc_StartProcess(ss, (Uint)stack, 0x202, cs, Entrypoint);
748 void Proc_StartProcess(Uint16 SS, Uint Stack, Uint Flags, Uint16 CS, Uint IP)
750 Uint *stack = (void*)Stack;
751 *--stack = SS; //Stack Segment
752 *--stack = Stack; //Stack Pointer
753 *--stack = Flags; //EFLAGS (Resvd (0x2) and IF (0x20))
754 *--stack = CS; //Code Segment
757 *--stack = 0xAAAAAAAA; // eax
758 *--stack = 0xCCCCCCCC; // ecx
759 *--stack = 0xDDDDDDDD; // edx
760 *--stack = 0xBBBBBBBB; // ebx
761 *--stack = 0xD1D1D1D1; // edi
762 *--stack = 0x54545454; // esp - NOT POPED
763 *--stack = 0x51515151; // esi
764 *--stack = 0xB4B4B4B4; // ebp
771 __asm__ __volatile__ (
772 "mov %%eax,%%esp;\n\t" // Set stack pointer
778 "iret;\n\t" : : "a" (stack));
783 * \fn int Proc_Demote(Uint *Err, int Dest, tRegs *Regs)
784 * \brief Demotes a process to a lower permission level
785 * \param Err Pointer to user's errno
786 * \param Dest New Permission Level
787 * \param Regs Pointer to user's register structure
789 int Proc_Demote(Uint *Err, int Dest, tRegs *Regs)
791 int cpl = Regs->cs & 3;
793 if(Dest > 3 || Dest < 0) {
804 // Change the Segment Registers
805 Regs->cs = (((Dest+1)<<4) | Dest) - 8;
806 Regs->ss = ((Dest+1)<<4) | Dest;
807 // Check if the GP Segs are GDT, then change them
808 if(!(Regs->ds & 4)) Regs->ds = ((Dest+1)<<4) | Dest;
809 if(!(Regs->es & 4)) Regs->es = ((Dest+1)<<4) | Dest;
810 if(!(Regs->fs & 4)) Regs->fs = ((Dest+1)<<4) | Dest;
811 if(!(Regs->gs & 4)) Regs->gs = ((Dest+1)<<4) | Dest;
817 * \brief Calls a signal handler in user mode
818 * \note Used for signals
820 void Proc_CallFaultHandler(tThread *Thread)
822 // Rewinds the stack and calls the user function
824 Proc_ReturnToUser( Thread->FaultHandler, Thread->CurFaultNum, Thread->KernelStack );
828 void Proc_DumpThreadCPUState(tThread *Thread)
830 if( Thread->CurCPU > -1 )
832 int maxBacktraceDistance = 6;
836 if( Thread->CurCPU != GetCPUNum() ) {
837 Log(" Currently running");
841 // Backtrace to find the IRQ entrypoint
842 // - This will usually only be called by an IRQ, so this should
844 __asm__ __volatile__ ("mov %%ebp, %0" : "=r" (stack));
845 while( maxBacktraceDistance -- )
850 if( stack[1] == (tVAddr)&IRQCommon_handled ) {
851 regs = (void*)stack[2];
855 stack = (void*)stack[0];
859 Log(" Unable to find IRQ Entry");
863 Log(" at %04x:%08x", regs->cs, regs->eip);
868 tVAddr diffFromScheduler = Thread->SavedState.EIP - (tVAddr)SwitchTasks;
869 tVAddr diffFromClone = Thread->SavedState.EIP - (tVAddr)Proc_CloneInt;
870 tVAddr diffFromSpawn = Thread->SavedState.EIP - (tVAddr)NewTaskHeader;
872 if( diffFromClone > 0 && diffFromClone < 40 ) // When I last checked, .newTask was at .+27
874 Log(" Creating process");
878 if( diffFromSpawn == 0 )
880 Log(" Creating thread");
884 if( diffFromScheduler > 0 && diffFromScheduler < 128 ) // When I last checked, GetEIP was at .+0x30
887 MM_ReadFromAddrSpace(Thread->MemState.CR3, Thread->SavedState.EBP, data, 12);
888 if( data[1] == (Uint32)&IRQCommon + 25 )
890 tRegs *regs = (void *) data[2];
891 Log(" oldebp = 0x%08x, ret = 0x%08x, regs = 0x%x",
892 data[0], data[1], data[2]
895 // [EBP+0x04] = Return Addr
896 // [EBP+0x08] = Arg 1 (CPU Number)
897 // [EBP+0x0C] = Arg 2 (Thread)
898 // [EBP+0x10] = GS (start of tRegs)
899 Log(" IRQ%i from %02x:%08x", regs->int_num regs->cs, regs->eip);
901 if( stack[1] == (Uint32)&scheduler_return )
905 Log(" At %04x:%08x", Thread->SavedState.UserCS, Thread->SavedState.UserEIP);
909 Log(" Just created (unknown %p)", Thread->SavedState.EIP);
912 void Proc_Reschedule(void)
914 tThread *nextthread, *curthread;
915 int cpu = GetCPUNum();
917 // TODO: Wait for it?
918 if(IS_LOCKED(&glThreadListLock)) return;
920 curthread = Proc_GetCurThread();
922 nextthread = Threads_GetNextToRun(cpu, curthread);
925 nextthread = gaCPUs[cpu].IdleThread;
926 if(!nextthread || nextthread == curthread)
929 #if DEBUG_TRACE_SWITCH
930 LogF("\nSwitching to task %i, CR3 = 0x%x, EIP = %p, ESP = %p\n",
932 nextthread->MemState.CR3,
933 nextthread->SavedState.EIP,
934 nextthread->SavedState.ESP
939 gaCPUs[cpu].Current = nextthread;
940 gTSSs[cpu].ESP0 = nextthread->KernelStack-4;
941 __asm__ __volatile__("mov %0, %%db0\n\t" : : "r"(nextthread) );
944 nextthread->SavedState.ESP, &curthread->SavedState.ESP,
945 nextthread->SavedState.EIP, &curthread->SavedState.EIP,
946 nextthread->MemState.CR3
952 * \fn void Proc_Scheduler(int CPU)
953 * \brief Swap current thread and clears dead threads
955 void Proc_Scheduler(int CPU)
959 // If the spinlock is set, let it complete
960 if(IS_LOCKED(&glThreadListLock)) return;
962 // Get current thread
963 thread = gaCPUs[CPU].Current;
969 // Reduce remaining quantum and continue timeslice if non-zero
970 if( thread->Remaining-- )
972 // Reset quantum for next call
973 thread->Remaining = thread->Quantum;
975 // TODO: Make this more stable somehow
976 __asm__ __volatile__("mov %%ebp, %0" : "=r" (ebp));
977 regs = (tRegs*)(ebp+(2+2)*4); // EBP,Ret + CPU,CurThread
978 thread->SavedState.UserCS = regs->cs;
979 thread->SavedState.UserEIP = regs->eip;
981 if(thread->bInstrTrace) {
982 regs->eflags |= 0x100; // Set TF
983 Log("%p De-scheduled", thread);
986 regs->eflags &= ~0x100; // Clear TF
993 gpMP_LocalAPIC->EOI.Val = 0;
997 __asm__ __volatile__ ("sti");
1003 EXPORT(Proc_SpawnWorker);