iokit/Kernel/IOCommandGate.cpp

   1 /*
   2  * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_OSREFERENCE_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
  10  * License may not be used to create, or enable the creation or
  11  * redistribution of, unlawful or unlicensed copies of an Apple operating
  12  * system, or to circumvent, violate, or enable the circumvention or
  13  * violation of, any terms of an Apple operating system software license
  14  * agreement.
  15  *
  16  * Please obtain a copy of the License at
  17  * http://www.opensource.apple.com/apsl/ and read it before using this
  18  * file.
  19  *
  20  * The Original Code and all software distributed under the License are
  21  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  22  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  23  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  25  * Please see the License for the specific language governing rights and
  26  * limitations under the License.
  27  *
  28  * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
  29  */
  30 #include <IOKit/IOCommandGate.h>
  31 #include <IOKit/IOWorkLoop.h>
  32 #include <IOKit/IOReturn.h>
  33 #include <IOKit/IOTimeStamp.h>
  34
  35 #define super IOEventSource
  36
  37 OSDefineMetaClassAndStructors(IOCommandGate, IOEventSource)
  38 OSMetaClassDefineReservedUnused(IOCommandGate, 0);
  39 OSMetaClassDefineReservedUnused(IOCommandGate, 1);
  40 OSMetaClassDefineReservedUnused(IOCommandGate, 2);
  41 OSMetaClassDefineReservedUnused(IOCommandGate, 3);
  42 OSMetaClassDefineReservedUnused(IOCommandGate, 4);
  43 OSMetaClassDefineReservedUnused(IOCommandGate, 5);
  44 OSMetaClassDefineReservedUnused(IOCommandGate, 6);
  45 OSMetaClassDefineReservedUnused(IOCommandGate, 7);
  46
  47 bool IOCommandGate::checkForWork() { return false; }
  48
  49 bool IOCommandGate::init(OSObject *inOwner, Action inAction)
  50 {
  51     return super::init(inOwner, (IOEventSource::Action) inAction);
  52 }
  53
  54 IOCommandGate *
  55 IOCommandGate::commandGate(OSObject *inOwner, Action inAction)
  56 {
  57     IOCommandGate *me = new IOCommandGate;
  58
  59     if (me && !me->init(inOwner, inAction)) {
  60         me->release();
  61         return 0;
  62     }
  63
  64     return me;
  65 }
  66
  67 IOReturn IOCommandGate::runCommand(void *arg0, void *arg1,
  68                                    void *arg2, void *arg3)
  69 {
  70     IOReturn res;
  71
  72     if (!enabled)
  73         return kIOReturnNotPermitted;
  74
  75     if (!action)
  76         return kIOReturnNoResources;
  77
  78     // closeGate is recursive so don't worry if we already hold the lock.
  79     IOTimeStampConstant(IODBG_CMDQ(IOCMDQ_ACTION),
  80                         (unsigned int) action, (unsigned int) owner);
  81
  82     closeGate();
  83     res = (*(Action) action)(owner, arg0, arg1, arg2, arg3);
  84     openGate();
  85
  86     return res;
  87 }
  88
  89 IOReturn IOCommandGate::runAction(Action inAction,
  90                                   void *arg0, void *arg1,
  91                                   void *arg2, void *arg3)
  92 {
  93     IOReturn res;
  94
  95     if (!enabled)
  96         return kIOReturnNotPermitted;
  97
  98     if (!inAction)
  99         return kIOReturnBadArgument;
 100
 101     IOTimeStampConstant(IODBG_CMDQ(IOCMDQ_ACTION),
 102                         (unsigned int) inAction, (unsigned int) owner);
 103
 104     // closeGate is recursive so don't worry if we already hold the lock.
 105     closeGate();
 106     res = (*inAction)(owner, arg0, arg1, arg2, arg3);
 107     openGate();
 108
 109     return res;
 110 }
 111
 112 IOReturn IOCommandGate::attemptCommand(void *arg0, void *arg1,
 113                                        void *arg2, void *arg3)
 114 {
 115     IOReturn res;
 116
 117     if (!enabled)
 118         return kIOReturnNotPermitted;
 119
 120     if (!action)
 121         return kIOReturnNoResources;
 122
 123     // Try to hold the lock if can't get return immediately.
 124     if (!tryCloseGate())
 125         return kIOReturnCannotLock;
 126
 127     // closeGate is recursive so don't worry if we already hold the lock.
 128     IOTimeStampConstant(IODBG_CMDQ(IOCMDQ_ACTION),
 129                         (unsigned int) action, (unsigned int) owner);
 130
 131     res = (*(Action) action)(owner, arg0, arg1, arg2, arg3);
 132     openGate();
 133
 134     return res;
 135 }
 136
 137 IOReturn IOCommandGate::attemptAction(Action inAction,
 138                                       void *arg0, void *arg1,
 139                                       void *arg2, void *arg3)
 140 {
 141     IOReturn res;
 142
 143     if (!enabled)
 144         return kIOReturnNotPermitted;
 145
 146     if (!inAction)
 147         return kIOReturnBadArgument;
 148
 149     // Try to close the gate if can't get return immediately.
 150     if (!tryCloseGate())
 151         return kIOReturnCannotLock;
 152
 153     IOTimeStampConstant(IODBG_CMDQ(IOCMDQ_ACTION),
 154                         (unsigned int) inAction, (unsigned int) owner);
 155
 156     res = (*inAction)(owner, arg0, arg1, arg2, arg3);
 157     openGate();
 158
 159     return res;
 160 }
 161
 162 IOReturn IOCommandGate::commandSleep(void *event, UInt32 interruptible)
 163 {
 164     if (!workLoop->inGate())
 165         return kIOReturnNotPermitted;
 166
 167     return sleepGate(event, interruptible);
 168 }
 169
 170 void IOCommandGate::commandWakeup(void *event, bool oneThread)
 171 {
 172     wakeupGate(event, oneThread);
 173 }