iokit/Kernel/IOCommandGate.cpp

   1 /*
   2  * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 #include <IOKit/IOCommandGate.h>
  29 #include <IOKit/IOWorkLoop.h>
  30 #include <IOKit/IOReturn.h>
  31 #include <IOKit/IOTimeStamp.h>
  32
  33 #define super IOEventSource
  34
  35 OSDefineMetaClassAndStructors(IOCommandGate, IOEventSource)
  36 OSMetaClassDefineReservedUnused(IOCommandGate, 0);
  37 OSMetaClassDefineReservedUnused(IOCommandGate, 1);
  38 OSMetaClassDefineReservedUnused(IOCommandGate, 2);
  39 OSMetaClassDefineReservedUnused(IOCommandGate, 3);
  40 OSMetaClassDefineReservedUnused(IOCommandGate, 4);
  41 OSMetaClassDefineReservedUnused(IOCommandGate, 5);
  42 OSMetaClassDefineReservedUnused(IOCommandGate, 6);
  43 OSMetaClassDefineReservedUnused(IOCommandGate, 7);
  44
  45 bool IOCommandGate::checkForWork() { return false; }
  46
  47 bool IOCommandGate::init(OSObject *inOwner, Action inAction)
  48 {
  49     return super::init(inOwner, (IOEventSource::Action) inAction);
  50 }
  51
  52 IOCommandGate *
  53 IOCommandGate::commandGate(OSObject *inOwner, Action inAction)
  54 {
  55     IOCommandGate *me = new IOCommandGate;
  56
  57     if (me && !me->init(inOwner, inAction)) {
  58         me->release();
  59         return 0;
  60     }
  61
  62     return me;
  63 }
  64
  65 IOReturn IOCommandGate::runCommand(void *arg0, void *arg1,
  66                                    void *arg2, void *arg3)
  67 {
  68     IOReturn res;
  69
  70     if (!enabled)
  71         return kIOReturnNotPermitted;
  72
  73     if (!action)
  74         return kIOReturnNoResources;
  75
  76     // closeGate is recursive so don't worry if we already hold the lock.
  77     IOTimeStampConstant(IODBG_CMDQ(IOCMDQ_ACTION),
  78                         (unsigned int) action, (unsigned int) owner);
  79
  80     closeGate();
  81     res = (*(Action) action)(owner, arg0, arg1, arg2, arg3);
  82     openGate();
  83
  84     return res;
  85 }
  86
  87 IOReturn IOCommandGate::runAction(Action inAction,
  88                                   void *arg0, void *arg1,
  89                                   void *arg2, void *arg3)
  90 {
  91     IOReturn res;
  92
  93     if (!enabled)
  94         return kIOReturnNotPermitted;
  95
  96     if (!inAction)
  97         return kIOReturnBadArgument;
  98
  99     IOTimeStampConstant(IODBG_CMDQ(IOCMDQ_ACTION),
 100                         (unsigned int) inAction, (unsigned int) owner);
 101
 102     // closeGate is recursive so don't worry if we already hold the lock.
 103     closeGate();
 104     res = (*inAction)(owner, arg0, arg1, arg2, arg3);
 105     openGate();
 106
 107     return res;
 108 }
 109
 110 IOReturn IOCommandGate::attemptCommand(void *arg0, void *arg1,
 111                                        void *arg2, void *arg3)
 112 {
 113     IOReturn res;
 114
 115     if (!enabled)
 116         return kIOReturnNotPermitted;
 117
 118     if (!action)
 119         return kIOReturnNoResources;
 120
 121     // Try to hold the lock if can't get return immediately.
 122     if (!tryCloseGate())
 123         return kIOReturnCannotLock;
 124
 125     // closeGate is recursive so don't worry if we already hold the lock.
 126     IOTimeStampConstant(IODBG_CMDQ(IOCMDQ_ACTION),
 127                         (unsigned int) action, (unsigned int) owner);
 128
 129     res = (*(Action) action)(owner, arg0, arg1, arg2, arg3);
 130     openGate();
 131
 132     return res;
 133 }
 134
 135 IOReturn IOCommandGate::attemptAction(Action inAction,
 136                                       void *arg0, void *arg1,
 137                                       void *arg2, void *arg3)
 138 {
 139     IOReturn res;
 140
 141     if (!enabled)
 142         return kIOReturnNotPermitted;
 143
 144     if (!inAction)
 145         return kIOReturnBadArgument;
 146
 147     // Try to close the gate if can't get return immediately.
 148     if (!tryCloseGate())
 149         return kIOReturnCannotLock;
 150
 151     IOTimeStampConstant(IODBG_CMDQ(IOCMDQ_ACTION),
 152                         (unsigned int) inAction, (unsigned int) owner);
 153
 154     res = (*inAction)(owner, arg0, arg1, arg2, arg3);
 155     openGate();
 156
 157     return res;
 158 }
 159
 160 IOReturn IOCommandGate::commandSleep(void *event, UInt32 interruptible)
 161 {
 162     if (!workLoop->inGate())
 163         return kIOReturnNotPermitted;
 164
 165     return sleepGate(event, interruptible);
 166 }
 167
 168 void IOCommandGate::commandWakeup(void *event, bool oneThread)
 169 {
 170     wakeupGate(event, oneThread);
 171 }