X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/ff6e181ae92fc6f1e89841290f461d1f2f9badd9..94ff46dc2849db4d43eaaf144872decc522aafb4:/iokit/Kernel/IOCommandGate.cpp diff --git a/iokit/Kernel/IOCommandGate.cpp b/iokit/Kernel/IOCommandGate.cpp index 8f3f46713..1ae9bcf08 100644 --- a/iokit/Kernel/IOCommandGate.cpp +++ b/iokit/Kernel/IOCommandGate.cpp @@ -1,15 +1,20 @@ /* - * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved. + * Copyright (c) 1998-2000, 2009-2010 Apple Inc. All rights reserved. + * + * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * - * @APPLE_LICENSE_HEADER_START@ - * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in - * compliance with the License. Please obtain a copy of the License at - * http://www.opensource.apple.com/apsl/ and read it before using this - * file. - * + * compliance with the License. The rights granted to you under the License + * may not be used to create, or enable the creation or redistribution of, + * unlawful or unlicensed copies of an Apple operating system, or to + * circumvent, violate, or enable the circumvention or violation of, any + * terms of an Apple operating system software license agreement. + * + * Please obtain a copy of the License at + * http://www.opensource.apple.com/apsl/ and read it before using this file. + * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, @@ -17,18 +22,25 @@ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. - * - * @APPLE_LICENSE_HEADER_END@ + * + * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ +#include + #include #include #include #include +#include #define super IOEventSource OSDefineMetaClassAndStructors(IOCommandGate, IOEventSource) +#if __LP64__ OSMetaClassDefineReservedUnused(IOCommandGate, 0); +#else +OSMetaClassDefineReservedUsed(IOCommandGate, 0); +#endif OSMetaClassDefineReservedUnused(IOCommandGate, 1); OSMetaClassDefineReservedUnused(IOCommandGate, 2); OSMetaClassDefineReservedUnused(IOCommandGate, 3); @@ -37,130 +49,285 @@ OSMetaClassDefineReservedUnused(IOCommandGate, 5); OSMetaClassDefineReservedUnused(IOCommandGate, 6); OSMetaClassDefineReservedUnused(IOCommandGate, 7); -bool IOCommandGate::checkForWork() { return false; } +#if IOKITSTATS + +#define IOStatisticsInitializeCounter() \ +do { \ + IOStatistics::setCounterType(IOEventSource::reserved->counter, kIOStatisticsCommandGateCounter); \ +} while (0) + +#define IOStatisticsActionCall() \ +do { \ + IOStatistics::countCommandGateActionCall(IOEventSource::reserved->counter); \ +} while (0) + +#else -bool IOCommandGate::init(OSObject *inOwner, Action inAction) +#define IOStatisticsInitializeCounter() +#define IOStatisticsActionCall() + +#endif /* IOKITSTATS */ + +bool +IOCommandGate::init(OSObject *inOwner, Action inAction) { - return super::init(inOwner, (IOEventSource::Action) inAction); + bool res = super::init(inOwner, (IOEventSource::Action) inAction); + if (res) { + IOStatisticsInitializeCounter(); + } + + return res; } IOCommandGate * IOCommandGate::commandGate(OSObject *inOwner, Action inAction) { - IOCommandGate *me = new IOCommandGate; + IOCommandGate *me = new IOCommandGate; - if (me && !me->init(inOwner, inAction)) { - me->release(); - return 0; - } + if (me && !me->init(inOwner, inAction)) { + me->release(); + return NULL; + } - return me; + return me; } -IOReturn IOCommandGate::runCommand(void *arg0, void *arg1, - void *arg2, void *arg3) +/* virtual */ void +IOCommandGate::disable() { - IOReturn res; + if (workLoop && !workLoop->inGate()) { + OSReportWithBacktrace("IOCommandGate::disable() called when not gated"); + } - if (!enabled) - return kIOReturnNotPermitted; + super::disable(); +} - if (!action) - return kIOReturnNoResources; +/* virtual */ void +IOCommandGate::enable() +{ + if (workLoop) { + closeGate(); + super::enable(); + wakeupGate(&enabled, /* oneThread */ false); // Unblock sleeping threads + openGate(); + } +} - // closeGate is recursive so don't worry if we already hold the lock. - IOTimeStampConstant(IODBG_CMDQ(IOCMDQ_ACTION), - (unsigned int) action, (unsigned int) owner); +/* virtual */ void +IOCommandGate::free() +{ + if (workLoop) { + setWorkLoop(NULL); + } + super::free(); +} - closeGate(); - res = (*(Action) action)(owner, arg0, arg1, arg2, arg3); - openGate(); +enum{ + kSleepersRemoved = 0x00000001, + kSleepersWaitEnabled = 0x00000002, + kSleepersActions = 0x00000100, + kSleepersActionsMask = 0xffffff00, +}; - return res; +/* virtual */ void +IOCommandGate::setWorkLoop(IOWorkLoop *inWorkLoop) +{ + IOWorkLoop * wl; + uintptr_t * sleepersP = (uintptr_t *) &reserved; + bool defer; + + if (!inWorkLoop && (wl = workLoop)) { // tearing down + wl->closeGate(); + *sleepersP |= kSleepersRemoved; + while (*sleepersP & kSleepersWaitEnabled) { + thread_wakeup_with_result(&enabled, THREAD_INTERRUPTED); + sleepGate(sleepersP, THREAD_UNINT); + } + *sleepersP &= ~kSleepersWaitEnabled; + defer = (0 != (kSleepersActionsMask & *sleepersP)); + if (!defer) { + super::setWorkLoop(NULL); + *sleepersP &= ~kSleepersRemoved; + } + wl->openGate(); + return; + } + + super::setWorkLoop(inWorkLoop); } -IOReturn IOCommandGate::runAction(Action inAction, - void *arg0, void *arg1, - void *arg2, void *arg3) +IOReturn +IOCommandGate::runCommand(void *arg0, void *arg1, + void *arg2, void *arg3) { - IOReturn res; - - if (!enabled) - return kIOReturnNotPermitted; - - if (!inAction) - return kIOReturnBadArgument; + return runAction((Action) action, arg0, arg1, arg2, arg3); +} - IOTimeStampConstant(IODBG_CMDQ(IOCMDQ_ACTION), - (unsigned int) inAction, (unsigned int) owner); +IOReturn +IOCommandGate::attemptCommand(void *arg0, void *arg1, + void *arg2, void *arg3) +{ + return attemptAction((Action) action, arg0, arg1, arg2, arg3); +} - // closeGate is recursive so don't worry if we already hold the lock. - closeGate(); - res = (*inAction)(owner, arg0, arg1, arg2, arg3); - openGate(); - return res; +static IOReturn +IOCommandGateActionToBlock(OSObject *owner, + void *arg0, void *arg1, + void *arg2, void *arg3) +{ + return ((IOEventSource::ActionBlock) arg0)(); } -IOReturn IOCommandGate::attemptCommand(void *arg0, void *arg1, - void *arg2, void *arg3) +IOReturn +IOCommandGate::runActionBlock(ActionBlock _action) { - IOReturn res; + return runAction(&IOCommandGateActionToBlock, _action); +} - if (!enabled) - return kIOReturnNotPermitted; +IOReturn +IOCommandGate::runAction(Action inAction, + void *arg0, void *arg1, + void *arg2, void *arg3) +{ + IOWorkLoop * wl; + uintptr_t * sleepersP; + + if (!inAction) { + return kIOReturnBadArgument; + } + if (!(wl = workLoop)) { + return kIOReturnNotReady; + } + + // closeGate is recursive needn't worry if we already hold the lock. + wl->closeGate(); + sleepersP = (uintptr_t *) &reserved; + + // If the command gate is disabled and we aren't on the workloop thread + // itself then sleep until we get enabled. + IOReturn res; + if (!wl->onThread()) { + while (!enabled) { + IOReturn sleepResult = kIOReturnSuccess; + if (workLoop) { + *sleepersP |= kSleepersWaitEnabled; + sleepResult = wl->sleepGate(&enabled, THREAD_INTERRUPTIBLE); + *sleepersP &= ~kSleepersWaitEnabled; + } + bool wakeupTearDown = (!workLoop || (0 != (*sleepersP & kSleepersRemoved))); + if ((kIOReturnSuccess != sleepResult) || wakeupTearDown) { + wl->openGate(); + + if (wakeupTearDown) { + wl->wakeupGate(sleepersP, false); // No further resources used + } + return kIOReturnAborted; + } + } + } + + bool trace = (gIOKitTrace & kIOTraceCommandGates) ? true : false; + + if (trace) { + IOTimeStampStartConstant(IODBG_CMDQ(IOCMDQ_ACTION), + VM_KERNEL_ADDRHIDE(inAction), VM_KERNEL_ADDRHIDE(owner)); + } + + IOStatisticsActionCall(); + + // Must be gated and on the work loop or enabled + + *sleepersP += kSleepersActions; + res = (*inAction)(owner, arg0, arg1, arg2, arg3); + *sleepersP -= kSleepersActions; + + if (trace) { + IOTimeStampEndConstant(IODBG_CMDQ(IOCMDQ_ACTION), + VM_KERNEL_ADDRHIDE(inAction), VM_KERNEL_ADDRHIDE(owner)); + } + + if (kSleepersRemoved == ((kSleepersActionsMask | kSleepersRemoved) & *sleepersP)) { + // no actions outstanding + *sleepersP &= ~kSleepersRemoved; + super::setWorkLoop(NULL); + } + + wl->openGate(); + + return res; +} - if (!action) - return kIOReturnNoResources; +IOReturn +IOCommandGate::attemptAction(Action inAction, + void *arg0, void *arg1, + void *arg2, void *arg3) +{ + IOReturn res; + IOWorkLoop * wl; - // Try to hold the lock if can't get return immediately. - if (!tryCloseGate()) - return kIOReturnCannotLock; + if (!inAction) { + return kIOReturnBadArgument; + } + if (!(wl = workLoop)) { + return kIOReturnNotReady; + } - // closeGate is recursive so don't worry if we already hold the lock. - IOTimeStampConstant(IODBG_CMDQ(IOCMDQ_ACTION), - (unsigned int) action, (unsigned int) owner); + // Try to close the gate if can't get return immediately. + if (!wl->tryCloseGate()) { + return kIOReturnCannotLock; + } - res = (*(Action) action)(owner, arg0, arg1, arg2, arg3); - openGate(); + // If the command gate is disabled then sleep until we get a wakeup + if (!wl->onThread() && !enabled) { + res = kIOReturnNotPermitted; + } else { + bool trace = (gIOKitTrace & kIOTraceCommandGates) ? true : false; - return res; -} + if (trace) { + IOTimeStampStartConstant(IODBG_CMDQ(IOCMDQ_ACTION), + VM_KERNEL_ADDRHIDE(inAction), VM_KERNEL_ADDRHIDE(owner)); + } -IOReturn IOCommandGate::attemptAction(Action inAction, - void *arg0, void *arg1, - void *arg2, void *arg3) -{ - IOReturn res; + IOStatisticsActionCall(); - if (!enabled) - return kIOReturnNotPermitted; + res = (*inAction)(owner, arg0, arg1, arg2, arg3); - if (!inAction) - return kIOReturnBadArgument; + if (trace) { + IOTimeStampEndConstant(IODBG_CMDQ(IOCMDQ_ACTION), + VM_KERNEL_ADDRHIDE(inAction), VM_KERNEL_ADDRHIDE(owner)); + } + } - // Try to close the gate if can't get return immediately. - if (!tryCloseGate()) - return kIOReturnCannotLock; + wl->openGate(); - IOTimeStampConstant(IODBG_CMDQ(IOCMDQ_ACTION), - (unsigned int) inAction, (unsigned int) owner); + return res; +} - res = (*inAction)(owner, arg0, arg1, arg2, arg3); - openGate(); +IOReturn +IOCommandGate::commandSleep(void *event, UInt32 interruptible) +{ + if (!workLoop->inGate()) { + /* The equivalent of 'msleep' while not holding the mutex is invalid */ + panic("invalid commandSleep while not holding the gate"); + } - return res; + return sleepGate(event, interruptible); } -IOReturn IOCommandGate::commandSleep(void *event, UInt32 interruptible) +IOReturn +IOCommandGate::commandSleep(void *event, AbsoluteTime deadline, UInt32 interruptible) { - if (!workLoop->inGate()) - return kIOReturnNotPermitted; + if (!workLoop->inGate()) { + /* The equivalent of 'msleep' while not holding the mutex is invalid */ + panic("invalid commandSleep while not holding the gate"); + } - return sleepGate(event, interruptible); + return sleepGate(event, deadline, interruptible); } -void IOCommandGate::commandWakeup(void *event, bool oneThread) +void +IOCommandGate::commandWakeup(void *event, bool oneThread) { - wakeupGate(event, oneThread); + wakeupGate(event, oneThread); }