| 1 | /*␊ |
| 2 | * Copyright (c) 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 | ␊ |
| 29 | /*␊ |
| 30 | *␊ |
| 31 | *␉Copyright (c) 2000 Apple Computer, Inc. All rights reserved.␊ |
| 32 | *␊ |
| 33 | *␉HISTORY␊ |
| 34 | *␊ |
| 35 | *␉2001-01-17␉gvdl␉Re-implement on IOCommandGate::commandSleep␊ |
| 36 | *␉11/13/2000␉CJS␉Created IOCommandPool class and implementation␊ |
| 37 | *␊ |
| 38 | */␊ |
| 39 | ␊ |
| 40 | /*!␊ |
| 41 | * @header IOCommandPool␊ |
| 42 | * @abstract␊ |
| 43 | * This header contains the IOCommandPool class definition.␊ |
| 44 | */␊ |
| 45 | ␊ |
| 46 | #ifndef _IOKIT_IO_COMMAND_POOL_H_␊ |
| 47 | #define _IOKIT_IO_COMMAND_POOL_H_␊ |
| 48 | ␊ |
| 49 | /*␊ |
| 50 | * Kernel␊ |
| 51 | */␊ |
| 52 | ␊ |
| 53 | #if defined(KERNEL) && defined(__cplusplus)␊ |
| 54 | ␊ |
| 55 | #include <kern/kern_types.h>␊ |
| 56 | #include <kern/queue.h>␊ |
| 57 | #include <IOKit/IOCommand.h>␊ |
| 58 | #include <IOKit/IOCommandGate.h>␊ |
| 59 | #include <IOKit/IOService.h>␊ |
| 60 | #include <IOKit/IOWorkLoop.h>␊ |
| 61 | ␊ |
| 62 | /*!␊ |
| 63 | * @class IOCommandPool␊ |
| 64 | * @abstract Manipulates a pool of commands which inherit from IOCommand.␊ |
| 65 | * @discussion␊ |
| 66 | * The IOCommandPool class is used to manipulate a pool of commands which␊ |
| 67 | * inherit from IOCommand. It includes a factory method to create a pool␊ |
| 68 | * of a certain size. Once the factory method is invoked, the semaphore␊ |
| 69 | * is set to zero. The caller must then put commands in the pool by creating␊ |
| 70 | * the command (via the controller's factory method or a memory allocation)␊ |
| 71 | * and calling the returnCommand method with the newly created command as its␊ |
| 72 | * argument.␊ |
| 73 | */␊ |
| 74 | ␊ |
| 75 | class IOCommandPool : public OSObject␊ |
| 76 | {␊ |
| 77 | ␉␊ |
| 78 | OSDeclareDefaultStructors(IOCommandPool)␊ |
| 79 | ␊ |
| 80 | ␊ |
| 81 | protected:␊ |
| 82 | ␊ |
| 83 | queue_head_t fQueueHead;␉/* head of the queue of elements available */␊ |
| 84 | UInt32 fSleepers;␉␉/* Count of threads sleeping on this pool */␊ |
| 85 | IOCommandGate *fSerializer;␉/* command gate used for serializing pool access */␊ |
| 86 | ␊ |
| 87 | /*! @struct ExpansionData␊ |
| 88 | @discussion This structure will be used to expand the capablilties of the IOEventSource in the future.␊ |
| 89 | */ ␊ |
| 90 | struct ExpansionData { };␊ |
| 91 | ␊ |
| 92 | /*! @var reserved␊ |
| 93 | Reserved for future use. (Internal use only) */␊ |
| 94 | ExpansionData *reserved;␊ |
| 95 | ␊ |
| 96 | /*!␊ |
| 97 | * @const kIOCommandPoolDefaultSize␊ |
| 98 | * @abstract The default size of any command pool.␊ |
| 99 | * @discussion␊ |
| 100 | * kIOCommandPoolDefaultSize is the default size of any command pool.␊ |
| 101 | * The default size was determined to be the smallest size for which␊ |
| 102 | * a pool makes sense.␊ |
| 103 | */␊ |
| 104 | ␊ |
| 105 | static const UInt32 kIOCommandPoolDefaultSize = 2;␊ |
| 106 | ␊ |
| 107 | /*␊ |
| 108 | * Free all of this object's outstanding resources.␊ |
| 109 | */␊ |
| 110 | ␊ |
| 111 | virtual void free(void);␊ |
| 112 | ␊ |
| 113 | ␊ |
| 114 | public:␊ |
| 115 | ␊ |
| 116 | /*!␊ |
| 117 | * @function initWithWorkLoop␊ |
| 118 | * @abstract Primary initializer for an IOCommandPool object.␊ |
| 119 | * @discussion Primary initializer for an IOCommandPool.␊ |
| 120 | * Should probably use IOCommandPool::withWorkLoop() as it is easier to use.␊ |
| 121 | * @param inWorkLoop␊ |
| 122 | * The workloop that this command pool should synchronize with.␊ |
| 123 | * @result Returns true if command pool was successfully initialized.␊ |
| 124 | */␊ |
| 125 | virtual bool initWithWorkLoop(IOWorkLoop *workLoop);␊ |
| 126 | ␊ |
| 127 | /*!␊ |
| 128 | * @function withWorkLoop␊ |
| 129 | * @abstract Primary factory method for the IOCommandPool class␊ |
| 130 | * @discussion␊ |
| 131 | * The withWorkLoop method is what is known as a factory method. It creates␊ |
| 132 | * a new instance of an IOCommandPool and returns a pointer to that object.␊ |
| 133 | * @param inWorkLoop␊ |
| 134 | * The workloop that this command pool should synchronize with.␊ |
| 135 | * @result␊ |
| 136 | * Returns a pointer to an instance of IOCommandPool if successful,␊ |
| 137 | * otherwise NULL.␊ |
| 138 | */␊ |
| 139 | ␊ |
| 140 | static IOCommandPool *withWorkLoop(IOWorkLoop *inWorkLoop);␊ |
| 141 | ␊ |
| 142 | /*!␊ |
| 143 | * @function init␊ |
| 144 | * @abstract Should never be used, obsolete. See initWithWorkLoop.␊ |
| 145 | */␊ |
| 146 | virtual bool init(IOService *inOwner,␊ |
| 147 | IOWorkLoop *inWorkLoop,␊ |
| 148 | UInt32 inSize = kIOCommandPoolDefaultSize);␊ |
| 149 | ␊ |
| 150 | /*!␊ |
| 151 | * @function withWorkLoop␊ |
| 152 | * @abstract Should never be used, obsolete. See IOCommandPool::withWorkLoop.␊ |
| 153 | */␊ |
| 154 | static IOCommandPool *commandPool(IOService *inOwner,␊ |
| 155 | IOWorkLoop *inWorkLoop,␊ |
| 156 | UInt32 inSize = kIOCommandPoolDefaultSize);␊ |
| 157 | ␊ |
| 158 | ␊ |
| 159 | /*!␊ |
| 160 | * @function getCommand␊ |
| 161 | * @discussion The getCommand method is used to get a pointer to an object of type IOCommand from the pool.␊ |
| 162 | * @param blockForCommand␊ |
| 163 | * If the caller would like to have its thread slept until a command is␊ |
| 164 | * available, it should pass true, else false.␊ |
| 165 | * @result␊ |
| 166 | * If the caller passes true in blockForCommand, getCommand guarantees that␊ |
| 167 | * the result will be a pointer to an IOCommand object from the pool. If␊ |
| 168 | * the caller passes false, s/he is responsible for checking whether a non-NULL␊ |
| 169 | * pointer was returned.␊ |
| 170 | */␊ |
| 171 | ␊ |
| 172 | virtual IOCommand *getCommand(bool blockForCommand = true);␊ |
| 173 | ␊ |
| 174 | /*!␊ |
| 175 | * @function returnCommand␊ |
| 176 | * @discussion␊ |
| 177 | * The returnCommand method is used to place an object of type IOCommand␊ |
| 178 | * into the pool, whether it be the first time, or the 1000th time.␊ |
| 179 | * @param commmand␊ |
| 180 | * The command to place in the pool.␊ |
| 181 | */␊ |
| 182 | ␊ |
| 183 | virtual void returnCommand(IOCommand *command);␊ |
| 184 | ␊ |
| 185 | protected:␊ |
| 186 | ␊ |
| 187 | /*!␊ |
| 188 | * @function gatedGetCommand␊ |
| 189 | * @discussion␊ |
| 190 | * The gatedGetCommand method is used to serialize the extraction of a ␊ |
| 191 | * command from the pool behind a command gate, runAction-ed by getCommand.␊ |
| 192 | * @param vCommand␊ |
| 193 | * A pointer to a pointer to an IOCommand object where the returned␊ |
| 194 | * command will be stored.␊ |
| 195 | * @param vBlock␊ |
| 196 | * A bool that indicates whether to block the request until a command␊ |
| 197 | * becomes available.␊ |
| 198 | * @result␊ |
| 199 | * Returns kIOReturnNoResources if no command is available and the client␊ |
| 200 | * doesn't wish to block until one does become available.␊ |
| 201 | * kIOReturnSuccess if the vCommand argument is valid.␊ |
| 202 | */␊ |
| 203 | virtual IOReturn gatedGetCommand(IOCommand **command, bool blockForCommand);␊ |
| 204 | ␊ |
| 205 | /*!␊ |
| 206 | * @function gatedReturnCommand␊ |
| 207 | * @discussion␊ |
| 208 | * The gatedReturnCommand method is used to serialize the return of a ␊ |
| 209 | * command to the pool behind a command gate, runAction-ed by returnCommand.␊ |
| 210 | * @param vCommand␊ |
| 211 | * A pointer to the IOCommand object to be returned to the pool.␊ |
| 212 | * @result␊ |
| 213 | * Always returns kIOReturnSuccess if the vCommand argument is valid.␊ |
| 214 | */␊ |
| 215 | virtual IOReturn gatedReturnCommand(IOCommand *command);␊ |
| 216 | ␊ |
| 217 | private:␊ |
| 218 | OSMetaClassDeclareReservedUnused(IOCommandPool, 0);␊ |
| 219 | OSMetaClassDeclareReservedUnused(IOCommandPool, 1);␊ |
| 220 | OSMetaClassDeclareReservedUnused(IOCommandPool, 2);␊ |
| 221 | OSMetaClassDeclareReservedUnused(IOCommandPool, 3);␊ |
| 222 | OSMetaClassDeclareReservedUnused(IOCommandPool, 4);␊ |
| 223 | OSMetaClassDeclareReservedUnused(IOCommandPool, 5);␊ |
| 224 | OSMetaClassDeclareReservedUnused(IOCommandPool, 6);␊ |
| 225 | OSMetaClassDeclareReservedUnused(IOCommandPool, 7);␊ |
| 226 | };␊ |
| 227 | ␊ |
| 228 | #endif␉/* defined(KERNEL) && defined(__cplusplus) */␊ |
| 229 | ␊ |
| 230 | #endif␉/* _IOKIT_IO_COMMAND_POOL_H_ */␊ |
| 231 | |
