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27  */
28 
29 #define IOKIT_ENABLE_SHARED_PTR
30 
31 #include <ptrauth.h>
32 #include <IOKit/IOInterruptEventSource.h>
33 #include <IOKit/IOKitDebug.h>
34 #include <IOKit/IOLib.h>
35 #include <IOKit/IOService.h>
36 #include <IOKit/IOInterrupts.h>
37 #include <IOKit/IOTimeStamp.h>
38 #include <IOKit/IOWorkLoop.h>
39 #include <IOKit/IOInterruptAccountingPrivate.h>
40 #include <libkern/Block_private.h>
41 
42 #if IOKITSTATS
43 
44 #define IOStatisticsInitializeCounter() \
45 do { \
46 	IOStatistics::setCounterType(IOEventSource::reserved->counter, kIOStatisticsInterruptEventSourceCounter); \
47 } while (0)
48 
49 #define IOStatisticsCheckForWork() \
50 do { \
51 	IOStatistics::countInterruptCheckForWork(IOEventSource::reserved->counter); \
52 } while (0)
53 
54 #define IOStatisticsInterrupt() \
55 do { \
56 	IOStatistics::countInterrupt(IOEventSource::reserved->counter); \
57 } while (0)
58 
59 #else
60 
61 #define IOStatisticsInitializeCounter()
62 #define IOStatisticsCheckForWork()
63 #define IOStatisticsInterrupt()
64 
65 #endif // IOKITSTATS
66 
67 #define super IOEventSource
68 
69 OSDefineMetaClassAndStructors(IOInterruptEventSource, IOEventSource)
70 OSMetaClassDefineReservedUnused(IOInterruptEventSource, 0);
71 OSMetaClassDefineReservedUnused(IOInterruptEventSource, 1);
72 OSMetaClassDefineReservedUnused(IOInterruptEventSource, 2);
73 OSMetaClassDefineReservedUnused(IOInterruptEventSource, 3);
74 OSMetaClassDefineReservedUnused(IOInterruptEventSource, 4);
75 OSMetaClassDefineReservedUnused(IOInterruptEventSource, 5);
76 OSMetaClassDefineReservedUnused(IOInterruptEventSource, 6);
77 OSMetaClassDefineReservedUnused(IOInterruptEventSource, 7);
78 
79 bool
init(OSObject * inOwner,Action inAction,IOService * inProvider,int inIntIndex)80 IOInterruptEventSource::init(OSObject *inOwner,
81     Action inAction,
82     IOService *inProvider,
83     int inIntIndex)
84 {
85 	bool res = true;
86 
87 	if (inIntIndex < 0) {
88 		return false;
89 	}
90 
91 	if (!super::init(inOwner, (IOEventSourceAction) inAction)) {
92 		return false;
93 	}
94 
95 	reserved = IOMallocType(ExpansionData);
96 
97 	provider = inProvider;
98 	producerCount = consumerCount = 0;
99 	autoDisable = explicitDisable = false;
100 	intIndex = ~inIntIndex;
101 
102 	// Assumes inOwner holds a reference(retain) on the provider
103 	if (inProvider) {
104 		if (IA_ANY_STATISTICS_ENABLED) {
105 			/*
106 			 * We only treat this as an "interrupt" if it has a provider; if it does,
107 			 * set up the objects necessary to track interrupt statistics.  Interrupt
108 			 * event sources without providers are most likely being used as simple
109 			 * event source in order to poke at workloops and kick off work.
110 			 *
111 			 * We also avoid try to avoid interrupt accounting overhead if none of
112 			 * the statistics are enabled.
113 			 */
114 			reserved->statistics = IOMallocType(IOInterruptAccountingData);
115 
116 			reserved->statistics->owner = this;
117 		}
118 
119 		res = (kIOReturnSuccess == registerInterruptHandler(inProvider, inIntIndex));
120 
121 		if (res) {
122 			intIndex = inIntIndex;
123 		}
124 	}
125 
126 	IOStatisticsInitializeCounter();
127 
128 	return res;
129 }
130 
131 IOReturn
registerInterruptHandler(IOService * inProvider,int inIntIndex)132 IOInterruptEventSource::registerInterruptHandler(IOService *inProvider,
133     int inIntIndex)
134 {
135 	IOReturn ret;
136 	int intType;
137 	IOInterruptAction intHandler;
138 
139 	ret = inProvider->getInterruptType(inIntIndex, &intType);
140 	if (kIOReturnSuccess != ret) {
141 		return ret;
142 	}
143 
144 	autoDisable = (intType == kIOInterruptTypeLevel);
145 	if (autoDisable) {
146 		intHandler = OSMemberFunctionCast(IOInterruptAction,
147 		    this, &IOInterruptEventSource::disableInterruptOccurred);
148 	} else {
149 		intHandler = OSMemberFunctionCast(IOInterruptAction,
150 		    this, &IOInterruptEventSource::normalInterruptOccurred);
151 	}
152 
153 	ret = provider->registerInterrupt(inIntIndex, this, intHandler);
154 
155 	/*
156 	 * Add statistics to the provider.  The setWorkLoop convention should ensure
157 	 * that we always go down the unregister path before we register (outside of
158 	 * init()), so we don't have to worry that we will invoke addInterruptStatistics
159 	 * erroneously.
160 	 */
161 	if ((ret == kIOReturnSuccess) && (reserved->statistics)) {
162 		/*
163 		 * Stash the normal index value, for the sake of debugging.
164 		 */
165 		reserved->statistics->interruptIndex = inIntIndex;
166 
167 		/*
168 		 * We need to hook the interrupt information up to the provider so that it
169 		 * can find the statistics for this interrupt when desired.  The provider is
170 		 * responsible for maintaining the reporter for a particular interrupt, and
171 		 * needs a handle on the statistics so that it can request that the reporter
172 		 * be updated as needed.  Errors are considered "soft" for the moment (it
173 		 * will either panic, or fail in a way such that we can still service the
174 		 * interrupt).
175 		 */
176 		provider->addInterruptStatistics(reserved->statistics, inIntIndex);
177 
178 		/*
179 		 * Add the statistics object to the global list of statistics objects; this
180 		 * is an aid to debugging (we can trivially find statistics for all eligible
181 		 * interrupts, and dump them; potentially helpful if the system is wedged
182 		 * due to interrupt activity).
183 		 */
184 		interruptAccountingDataAddToList(reserved->statistics);
185 	}
186 
187 	return ret;
188 }
189 
190 void
unregisterInterruptHandler(IOService * inProvider,int inIntIndex)191 IOInterruptEventSource::unregisterInterruptHandler(IOService *inProvider,
192     int inIntIndex)
193 {
194 	if (reserved->statistics) {
195 		interruptAccountingDataRemoveFromList(reserved->statistics);
196 		provider->removeInterruptStatistics(reserved->statistics->interruptIndex);
197 	}
198 
199 	provider->unregisterInterrupt(inIntIndex);
200 }
201 
202 
203 OSSharedPtr<IOInterruptEventSource>
interruptEventSource(OSObject * inOwner,Action inAction,IOService * inProvider,int inIntIndex)204 IOInterruptEventSource::interruptEventSource(OSObject *inOwner,
205     Action inAction,
206     IOService *inProvider,
207     int inIntIndex)
208 {
209 	OSSharedPtr<IOInterruptEventSource> me = OSMakeShared<IOInterruptEventSource>();
210 
211 	if (me && !me->init(inOwner, inAction, inProvider, inIntIndex)) {
212 		return nullptr;
213 	}
214 
215 	return me;
216 }
217 
218 OSSharedPtr<IOInterruptEventSource>
interruptEventSource(OSObject * inOwner,IOService * inProvider,int inIntIndex,ActionBlock inAction)219 IOInterruptEventSource::interruptEventSource(OSObject *inOwner,
220     IOService *inProvider,
221     int inIntIndex,
222     ActionBlock inAction)
223 {
224 	OSSharedPtr<IOInterruptEventSource> ies;
225 	ies = IOInterruptEventSource::interruptEventSource(inOwner, (Action) NULL, inProvider, inIntIndex);
226 	if (ies) {
227 		ies->setActionBlock((IOEventSource::ActionBlock) inAction);
228 	}
229 
230 	return ies;
231 }
232 
233 void
free()234 IOInterruptEventSource::free()
235 {
236 	if (provider && intIndex >= 0) {
237 		unregisterInterruptHandler(provider, intIndex);
238 	}
239 
240 	if (reserved) {
241 		if (reserved->statistics) {
242 			IOFreeType(reserved->statistics, IOInterruptAccountingData);
243 		}
244 
245 		IOFreeType(reserved, ExpansionData);
246 	}
247 
248 	super::free();
249 }
250 
251 void
enable()252 IOInterruptEventSource::enable()
253 {
254 	if (provider && intIndex >= 0) {
255 		provider->enableInterrupt(intIndex);
256 		explicitDisable = false;
257 		enabled = true;
258 	}
259 }
260 
261 void
disable()262 IOInterruptEventSource::disable()
263 {
264 	if (provider && intIndex >= 0) {
265 		provider->disableInterrupt(intIndex);
266 		explicitDisable = true;
267 		enabled = false;
268 	}
269 }
270 
271 void
setWorkLoop(IOWorkLoop * inWorkLoop)272 IOInterruptEventSource::setWorkLoop(IOWorkLoop *inWorkLoop)
273 {
274 	if (inWorkLoop) {
275 		super::setWorkLoop(inWorkLoop);
276 	}
277 
278 	if (provider) {
279 		if (!inWorkLoop) {
280 			if (intIndex >= 0) {
281 				/*
282 				 * It isn't necessarily safe to wait until free() to unregister the interrupt;
283 				 * our provider may disappear.
284 				 */
285 				unregisterInterruptHandler(provider, intIndex);
286 				intIndex = ~intIndex;
287 			}
288 		} else if ((intIndex < 0) && (kIOReturnSuccess == registerInterruptHandler(provider, ~intIndex))) {
289 			intIndex = ~intIndex;
290 		}
291 	}
292 
293 	if (!inWorkLoop) {
294 		super::setWorkLoop(inWorkLoop);
295 	}
296 }
297 
298 const IOService *
getProvider() const299 IOInterruptEventSource::getProvider() const
300 {
301 	return provider;
302 }
303 
304 int
getIntIndex() const305 IOInterruptEventSource::getIntIndex() const
306 {
307 	return intIndex;
308 }
309 
310 bool
getAutoDisable() const311 IOInterruptEventSource::getAutoDisable() const
312 {
313 	return autoDisable;
314 }
315 
316 bool
checkForWork()317 IOInterruptEventSource::checkForWork()
318 {
319 	uint64_t startSystemTime = 0;
320 	uint64_t endSystemTime = 0;
321 	uint64_t startCPUTime = 0;
322 	uint64_t endCPUTime = 0;
323 	unsigned int cacheProdCount = producerCount;
324 	int numInts = cacheProdCount - consumerCount;
325 	IOEventSource::Action intAction = action;
326 	ActionBlock intActionBlock = (ActionBlock) actionBlock;
327 	void *address;
328 	bool trace = (gIOKitTrace & kIOTraceIntEventSource) ? true : false;
329 
330 	if (kActionBlock & flags) {
331 		address = ptrauth_nop_cast(void *, _Block_get_invoke_fn((struct Block_layout *)intActionBlock));
332 	} else {
333 		address = ptrauth_nop_cast(void *, intAction);
334 	}
335 
336 	IOStatisticsCheckForWork();
337 
338 	if (numInts > 0) {
339 		if (trace) {
340 			IOTimeStampStartConstant(IODBG_INTES(IOINTES_ACTION),
341 			    VM_KERNEL_ADDRHIDE(address),
342 			    VM_KERNEL_ADDRHIDE(owner),
343 			    VM_KERNEL_ADDRHIDE(this), VM_KERNEL_ADDRHIDE(workLoop));
344 		}
345 
346 		if (reserved->statistics) {
347 			if (IA_GET_STATISTIC_ENABLED(kInterruptAccountingSecondLevelSystemTimeIndex)) {
348 				startSystemTime = mach_absolute_time();
349 			}
350 
351 			if (IA_GET_STATISTIC_ENABLED(kInterruptAccountingSecondLevelCPUTimeIndex)) {
352 				startCPUTime = thread_get_runtime_self();
353 			}
354 		}
355 
356 		// Call the handler
357 		if (kActionBlock & flags) {
358 			(intActionBlock)(this, numInts);
359 		} else {
360 			((IOInterruptEventAction)intAction)(owner, this, numInts);
361 		}
362 
363 		if (reserved->statistics) {
364 			if (IA_GET_STATISTIC_ENABLED(kInterruptAccountingSecondLevelCountIndex)) {
365 				IA_ADD_VALUE(&reserved->statistics->interruptStatistics[kInterruptAccountingSecondLevelCountIndex], 1);
366 			}
367 
368 			if (IA_GET_STATISTIC_ENABLED(kInterruptAccountingSecondLevelCPUTimeIndex)) {
369 				endCPUTime = thread_get_runtime_self();
370 				IA_ADD_VALUE(&reserved->statistics->interruptStatistics[kInterruptAccountingSecondLevelCPUTimeIndex], endCPUTime - startCPUTime);
371 			}
372 
373 			if (IA_GET_STATISTIC_ENABLED(kInterruptAccountingSecondLevelSystemTimeIndex)) {
374 				endSystemTime = mach_absolute_time();
375 				IA_ADD_VALUE(&reserved->statistics->interruptStatistics[kInterruptAccountingSecondLevelSystemTimeIndex], endSystemTime - startSystemTime);
376 			}
377 		}
378 
379 		if (trace) {
380 			IOTimeStampEndConstant(IODBG_INTES(IOINTES_ACTION),
381 			    VM_KERNEL_ADDRHIDE(address),
382 			    VM_KERNEL_ADDRHIDE(owner),
383 			    VM_KERNEL_ADDRHIDE(this), VM_KERNEL_ADDRHIDE(workLoop));
384 		}
385 
386 		consumerCount = cacheProdCount;
387 		if (autoDisable && !explicitDisable) {
388 			enable();
389 		}
390 	} else if (numInts < 0) {
391 		if (trace) {
392 			IOTimeStampStartConstant(IODBG_INTES(IOINTES_ACTION),
393 			    VM_KERNEL_ADDRHIDE(address),
394 			    VM_KERNEL_ADDRHIDE(owner),
395 			    VM_KERNEL_ADDRHIDE(this), VM_KERNEL_ADDRHIDE(workLoop));
396 		}
397 
398 		if (reserved->statistics) {
399 			if (IA_GET_STATISTIC_ENABLED(kInterruptAccountingSecondLevelSystemTimeIndex)) {
400 				startSystemTime = mach_absolute_time();
401 			}
402 
403 			if (IA_GET_STATISTIC_ENABLED(kInterruptAccountingSecondLevelCPUTimeIndex)) {
404 				startCPUTime = thread_get_runtime_self();
405 			}
406 		}
407 
408 		// Call the handler
409 		if (kActionBlock & flags) {
410 			(intActionBlock)(this, numInts);
411 		} else {
412 			((IOInterruptEventAction)intAction)(owner, this, numInts);
413 		}
414 
415 		if (reserved->statistics) {
416 			if (IA_GET_STATISTIC_ENABLED(kInterruptAccountingSecondLevelSystemTimeIndex)) {
417 				endSystemTime = mach_absolute_time();
418 				IA_ADD_VALUE(&reserved->statistics->interruptStatistics[kInterruptAccountingSecondLevelSystemTimeIndex], endSystemTime - startSystemTime);
419 			}
420 
421 			if (IA_GET_STATISTIC_ENABLED(kInterruptAccountingSecondLevelCPUTimeIndex)) {
422 				endCPUTime = thread_get_runtime_self();
423 				IA_ADD_VALUE(&reserved->statistics->interruptStatistics[kInterruptAccountingSecondLevelCPUTimeIndex], endCPUTime - startCPUTime);
424 			}
425 
426 			if (IA_GET_STATISTIC_ENABLED(kInterruptAccountingSecondLevelCountIndex)) {
427 				IA_ADD_VALUE(&reserved->statistics->interruptStatistics[kInterruptAccountingSecondLevelCountIndex], 1);
428 			}
429 		}
430 
431 		if (trace) {
432 			IOTimeStampEndConstant(IODBG_INTES(IOINTES_ACTION),
433 			    VM_KERNEL_ADDRHIDE(address),
434 			    VM_KERNEL_ADDRHIDE(owner),
435 			    VM_KERNEL_ADDRHIDE(this), VM_KERNEL_ADDRHIDE(workLoop));
436 		}
437 
438 		consumerCount = cacheProdCount;
439 		if (autoDisable && !explicitDisable) {
440 			enable();
441 		}
442 	}
443 
444 	return false;
445 }
446 
447 void
normalInterruptOccurred(void *,IOService *,int)448 IOInterruptEventSource::normalInterruptOccurred
449 (void */*refcon*/, IOService */*prov*/, int /*source*/)
450 {
451 	bool trace = (gIOKitTrace & kIOTraceIntEventSource) ? true : false;
452 
453 	IOStatisticsInterrupt();
454 	producerCount++;
455 
456 	if (trace) {
457 		IOTimeStampStartConstant(IODBG_INTES(IOINTES_SEMA), VM_KERNEL_ADDRHIDE(this), VM_KERNEL_ADDRHIDE(owner));
458 	}
459 
460 	if (reserved->statistics) {
461 		if (reserved->statistics->enablePrimaryTimestamp) {
462 			reserved->statistics->primaryTimestamp = mach_absolute_time();
463 		}
464 		if (IA_GET_STATISTIC_ENABLED(kInterruptAccountingFirstLevelCountIndex)) {
465 			IA_ADD_VALUE(&reserved->statistics->interruptStatistics[kInterruptAccountingFirstLevelCountIndex], 1);
466 		}
467 	}
468 
469 	signalWorkAvailable();
470 
471 	if (trace) {
472 		IOTimeStampEndConstant(IODBG_INTES(IOINTES_SEMA), VM_KERNEL_ADDRHIDE(this), VM_KERNEL_ADDRHIDE(owner));
473 	}
474 }
475 
476 void
disableInterruptOccurred(void *,IOService * prov,int source)477 IOInterruptEventSource::disableInterruptOccurred
478 (void */*refcon*/, IOService *prov, int source)
479 {
480 	bool trace = (gIOKitTrace & kIOTraceIntEventSource) ? true : false;
481 
482 	prov->disableInterrupt(source); /* disable the interrupt */
483 
484 	IOStatisticsInterrupt();
485 	producerCount++;
486 
487 	if (trace) {
488 		IOTimeStampStartConstant(IODBG_INTES(IOINTES_SEMA), VM_KERNEL_ADDRHIDE(this), VM_KERNEL_ADDRHIDE(owner));
489 	}
490 
491 	if (reserved->statistics) {
492 		if (reserved->statistics->enablePrimaryTimestamp) {
493 			reserved->statistics->primaryTimestamp = mach_absolute_time();
494 		}
495 		if (IA_GET_STATISTIC_ENABLED(kInterruptAccountingFirstLevelCountIndex)) {
496 			IA_ADD_VALUE(&reserved->statistics->interruptStatistics[kInterruptAccountingFirstLevelCountIndex], 1);
497 		}
498 	}
499 
500 	signalWorkAvailable();
501 
502 	if (trace) {
503 		IOTimeStampEndConstant(IODBG_INTES(IOINTES_SEMA), VM_KERNEL_ADDRHIDE(this), VM_KERNEL_ADDRHIDE(owner));
504 	}
505 }
506 
507 void
interruptOccurred(void * _refcon,IOService * prov,int source)508 IOInterruptEventSource::interruptOccurred
509 (void *_refcon, IOService *prov, int source)
510 {
511 	if (autoDisable && prov) {
512 		disableInterruptOccurred(_refcon, prov, source);
513 	} else {
514 		normalInterruptOccurred(_refcon, prov, source);
515 	}
516 }
517 
518 IOReturn
warmCPU(uint64_t abstime)519 IOInterruptEventSource::warmCPU
520 (uint64_t abstime)
521 {
522 	return ml_interrupt_prewarm(abstime);
523 }
524 
525 void
enablePrimaryInterruptTimestamp(bool enable)526 IOInterruptEventSource::enablePrimaryInterruptTimestamp(bool enable)
527 {
528 	if (reserved->statistics) {
529 		reserved->statistics->enablePrimaryTimestamp = enable;
530 	}
531 }
532 
533 uint64_t
getPrimaryInterruptTimestamp()534 IOInterruptEventSource::getPrimaryInterruptTimestamp()
535 {
536 	if (reserved->statistics && reserved->statistics->enablePrimaryTimestamp) {
537 		return reserved->statistics->primaryTimestamp;
538 	}
539 	return -1ULL;
540 }
541