| 1 | /*␊ |
| 2 | * Copyright (c) 1998-2008 Apple Inc. All rights reserved.␊ |
| 3 | *␊ |
| 4 | * @APPLE_LICENSE_HEADER_START@␊ |
| 5 | * ␊ |
| 6 | * The contents of this file constitute Original Code as defined in and␊ |
| 7 | * are subject to the Apple Public Source License Version 1.1 (the␊ |
| 8 | * "License"). You may not use this file except in compliance with the␊ |
| 9 | * License. Please obtain a copy of the License at␊ |
| 10 | * http://www.apple.com/publicsource and read it before using this file.␊ |
| 11 | * ␊ |
| 12 | * This Original Code and all software distributed under the License are␊ |
| 13 | * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER␊ |
| 14 | * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,␊ |
| 15 | * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,␊ |
| 16 | * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the␊ |
| 17 | * License for the specific language governing rights and limitations␊ |
| 18 | * under the License.␊ |
| 19 | * ␊ |
| 20 | * @APPLE_LICENSE_HEADER_END@␊ |
| 21 | */␊ |
| 22 | ␊ |
| 23 | #ifndef _IOPACKETQUEUE_H␊ |
| 24 | #define _IOPACKETQUEUE_H␊ |
| 25 | ␊ |
| 26 | #include <libkern/c++/OSObject.h>␊ |
| 27 | #include <IOKit/IOLocks.h>␊ |
| 28 | extern "C" {␊ |
| 29 | #include <sys/kpi_mbuf.h>␊ |
| 30 | }␊ |
| 31 | // Forward declarations.␊ |
| 32 | //␊ |
| 33 | struct mbuf;␊ |
| 34 | struct IOMbufQueue;␊ |
| 35 | ␊ |
| 36 | // We do not want the enqueue/dequeue macros defined in queue.h.␊ |
| 37 | //␊ |
| 38 | // #warning queue.h should not be included␊ |
| 39 | #undef enqueue(queue,elt)␊ |
| 40 | #undef dequeue(queue)␊ |
| 41 | ␊ |
| 42 | /*! @class IOPacketQueue␊ |
| 43 | @abstract Implements a bounded FIFO queue of mbuf packets. ␊ |
| 44 | @discussion Packets are␊ |
| 45 | removed from the head of the queue (dequeue), and new packets are added␊ |
| 46 | to the tail of the queue (enqueue). A spinlock is used to synchronize␊ |
| 47 | access to the queue between methods that have a "lock" prefix. ␊ |
| 48 | */␊ |
| 49 | ␊ |
| 50 | class IOPacketQueue : public OSObject␊ |
| 51 | { ␊ |
| 52 | OSDeclareDefaultStructors( IOPacketQueue )␊ |
| 53 | ␊ |
| 54 | protected:␊ |
| 55 | IOMbufQueue * _queue; // mbuf queue␊ |
| 56 | IOSimpleLock * _lock; // spinlock for synchronized methods␊ |
| 57 | ␊ |
| 58 | struct ExpansionData { };␊ |
| 59 | /*! @var reserved␊ |
| 60 | Reserved for future use. (Internal use only) */␊ |
| 61 | ExpansionData *_reserved;␊ |
| 62 | ␊ |
| 63 | /*! @function free␊ |
| 64 | @abstract Frees the IOPacketQueue object.␊ |
| 65 | @discussion All packets held by the queue are released back to the free␊ |
| 66 | pool, resource are deallocated, then super::free() is called. ␊ |
| 67 | */␊ |
| 68 | ␊ |
| 69 | virtual void free();␊ |
| 70 | ␊ |
| 71 | /*! @var IOPacketQueueDefaultCapacity ␊ |
| 72 | @abstract Describes the default capacity of the ␊ |
| 73 | queue object. ␊ |
| 74 | @discussion The capacity is only observed by the enqueue() method.␊ |
| 75 | Therefore, it is possible for the size of the queue to exceed its␊ |
| 76 | capacity when other methods, such as prepend(), are used to add packets␊ |
| 77 | to the queue. ␊ |
| 78 | */␊ |
| 79 | ␊ |
| 80 | static const UInt32 IOPacketQueueDefaultCapacity = 100;␊ |
| 81 | ␊ |
| 82 | public:␊ |
| 83 | ␊ |
| 84 | /*! @function withCapacity␊ |
| 85 | @abstract Factory method that constructs and initializes an␊ |
| 86 | IOPacketQueue object.␊ |
| 87 | @param capacity The initial capacity of the queue object. Can be␊ |
| 88 | later changed by calling the setCapacity() method.␊ |
| 89 | @result Returns an IOPacketQueue instance on success, or 0 otherwise. ␊ |
| 90 | */␊ |
| 91 | ␊ |
| 92 | static IOPacketQueue * withCapacity(UInt32 capacity = ␊ |
| 93 | IOPacketQueueDefaultCapacity);␊ |
| 94 | ␊ |
| 95 | /*! @function initWithCapacity␊ |
| 96 | @abstract Initializes an IOPacketQueue object.␊ |
| 97 | @discussion This method initializes an IOPacketQueue object with the given capacity.␊ |
| 98 | @param capacity The initial capacity of the queue. Can be later changed␊ |
| 99 | by calling the setCapacity() method.␊ |
| 100 | @result Returns true if initialized successfully, false otherwise. ␊ |
| 101 | */␊ |
| 102 | ␊ |
| 103 | virtual bool initWithCapacity(UInt32 capacity = ␊ |
| 104 | IOPacketQueueDefaultCapacity);␊ |
| 105 | ␊ |
| 106 | /*! @function getSize␊ |
| 107 | @abstract Gets the size of the queue.␊ |
| 108 | @result Returns the number of packets currently held by the queue. ␊ |
| 109 | */␊ |
| 110 | ␊ |
| 111 | virtual UInt32 getSize() const;␊ |
| 112 | ␊ |
| 113 | /*! @function setCapacity␊ |
| 114 | @abstract Changes the capacity of the queue.␊ |
| 115 | @param capacity The new capacity.␊ |
| 116 | @result Returns true if the new capacity was accepted, false otherwise. ␊ |
| 117 | */␊ |
| 118 | ␊ |
| 119 | virtual bool setCapacity(UInt32 capacity);␊ |
| 120 | ␊ |
| 121 | /*! @function getCapacity␊ |
| 122 | @abstract Gets the current capacity of the queue.␊ |
| 123 | @result Returns the current queue capacity. ␊ |
| 124 | */␊ |
| 125 | ␊ |
| 126 | virtual UInt32 getCapacity() const;␊ |
| 127 | ␊ |
| 128 | /*! @function peek␊ |
| 129 | @abstract Examines the packet at the head of the queue without␊ |
| 130 | removing it from the queue.␊ |
| 131 | @discussion A following call to peek() or dequeue() will return␊ |
| 132 | the same packet. The caller must never modify the mbuf packet returned.␊ |
| 133 | @result Returns the packet at the head of the queue. ␊ |
| 134 | */␊ |
| 135 | ␊ |
| 136 | virtual const mbuf_t peek() const;␊ |
| 137 | ␊ |
| 138 | /*! @function prepend␊ |
| 139 | @abstract Adds a chain of packets to the head of the queue.␊ |
| 140 | @param m A chain of packets to add to the head of the queue. ␊ |
| 141 | */␊ |
| 142 | ␊ |
| 143 | virtual void prepend(mbuf_t m);␊ |
| 144 | ␊ |
| 145 | /*! @function prepend␊ |
| 146 | @abstract Removes all packets from the specified queue, and adds them␊ |
| 147 | to the head of this queue.␊ |
| 148 | @param queue The source IOPacketQueue object containing the packets to␊ |
| 149 | be transferred. ␊ |
| 150 | */␊ |
| 151 | ␊ |
| 152 | virtual void prepend(IOPacketQueue * queue);␊ |
| 153 | ␊ |
| 154 | /*! @function lockPrepend␊ |
| 155 | @abstract Adds a chain of packets to the head of a synchronized queue.␊ |
| 156 | @discussion A spinlock is used to synchronize access to the queue.␊ |
| 157 | @param m A chain of packets to add to the head of the queue.␊ |
| 158 | @result Always returns true. ␊ |
| 159 | */␊ |
| 160 | ␊ |
| 161 | virtual void lockPrepend(mbuf_t m);␊ |
| 162 | ␊ |
| 163 | /*! @function enqueue␊ |
| 164 | @abstract Adds a chain of packets to the tail of the queue.␊ |
| 165 | @discussion Packets are not added if the size of the queue has reached␊ |
| 166 | its capacity.␊ |
| 167 | @param m A chain of packets to add to the tail of the queue.␊ |
| 168 | @result Returns true on success, or false to indicate over-capacity and refusal␊ |
| 169 | to accept the packet chain provided. ␊ |
| 170 | */␊ |
| 171 | ␊ |
| 172 | virtual bool enqueue(mbuf_t m);␊ |
| 173 | ␊ |
| 174 | /*! @function enqueue␊ |
| 175 | @abstract Removes all packets from the specified queue, and adds them␊ |
| 176 | to the tail of this queue.␊ |
| 177 | @param queue The source IOPacketQueue object containing the packets to␊ |
| 178 | be transferred.␊ |
| 179 | @result Always returns true. ␊ |
| 180 | */␊ |
| 181 | ␊ |
| 182 | virtual bool enqueue(IOPacketQueue * queue);␊ |
| 183 | ␊ |
| 184 | /*! @function enqueueWithDrop␊ |
| 185 | @abstract Adds a chain of packets to the tail of the queue. ␊ |
| 186 | @discussion Packets are␊ |
| 187 | dropped if the size of the queue has reached its capacity.␊ |
| 188 | @param m A chain of packets to add to the tail of the queue.␊ |
| 189 | @result Returns the number of packets dropped and freed by the queue. ␊ |
| 190 | */␊ |
| 191 | ␊ |
| 192 | virtual UInt32 enqueueWithDrop(mbuf_t m);␊ |
| 193 | ␊ |
| 194 | /*! @function lockEnqueue␊ |
| 195 | @abstract Adds a chain of packets to the tail of a synchronized queue.␊ |
| 196 | @discussion Packets are not added if the size of the queue has reached␊ |
| 197 | its capacity. A spinlock is used to synchronize access to the queue.␊ |
| 198 | @param m A chain of packets to add to the tail of the queue.␊ |
| 199 | @result Returns true on success, or false to indicate over-capacity and refusal␊ |
| 200 | to accept the packet chain provided.␊ |
| 201 | */␊ |
| 202 | ␊ |
| 203 | virtual bool lockEnqueue(mbuf_t m);␊ |
| 204 | ␊ |
| 205 | /*! @function lockEnqueueWithDrop␊ |
| 206 | @abstract Adds a chain of packets to the tail of a synchronized queue.␊ |
| 207 | @discussion Packets are dropped if the size of the queue has reached its capacity. A spinlock is used to synchronize access to the queue.␊ |
| 208 | @param m A chain of packets to add to the tail of the queue.␊ |
| 209 | @result Returns the number of packets dropped and freed by the queue. ␊ |
| 210 | */␊ |
| 211 | ␊ |
| 212 | virtual UInt32 lockEnqueueWithDrop(mbuf_t m);␊ |
| 213 | ␊ |
| 214 | /*! @function dequeue␊ |
| 215 | @abstract Removes a single packet from the head of the queue.␊ |
| 216 | @result Returns a packet removed from the head of the queue, or NULL if the␊ |
| 217 | queue was empty. ␊ |
| 218 | */␊ |
| 219 | ␊ |
| 220 | virtual mbuf_t dequeue();␊ |
| 221 | ␊ |
| 222 | /*! @function lockDequeue␊ |
| 223 | @abstract Removes a single packet from the head of a synchronized queue.␊ |
| 224 | @discussion A spinlock is used to synchronize access to the queue.␊ |
| 225 | @result Returns a packet removed from the head of the queue, or NULL if the␊ |
| 226 | queue was empty. ␊ |
| 227 | */␊ |
| 228 | ␊ |
| 229 | virtual mbuf_t lockDequeue();␊ |
| 230 | ␊ |
| 231 | /*! @function dequeueAll␊ |
| 232 | @abstract Removes all packets from the queue and returns the head of the␊ |
| 233 | packet chain.␊ |
| 234 | @discussion The size of the queue is cleared to zero.␊ |
| 235 | @result Returns the head of a packet chain linking all packets that were held␊ |
| 236 | in the queue, or NULL if the queue was empty. ␊ |
| 237 | */␊ |
| 238 | ␊ |
| 239 | virtual mbuf_t dequeueAll();␊ |
| 240 | ␊ |
| 241 | /*! @function lockDequeueAll␊ |
| 242 | @abstract Removes all packets from a synchronized queue and returns the␊ |
| 243 | head of the packet chain.␊ |
| 244 | @discussion The size of the queue is cleared to zero. A spinlock is used␊ |
| 245 | to synchronize access to the queue.␊ |
| 246 | @result Returns the head of a packet chain linking all packets that were held␊ |
| 247 | in the queue, or NULL if the queue was empty. ␊ |
| 248 | */␊ |
| 249 | ␊ |
| 250 | virtual mbuf_t lockDequeueAll();␊ |
| 251 | ␊ |
| 252 | /*! @function flush␊ |
| 253 | @abstract Frees all packets currently held in the queue and releases them␊ |
| 254 | back to the free mbuf pool.␊ |
| 255 | @discussion The size of the queue is cleared to zero.␊ |
| 256 | @result Returns the number of packets freed. ␊ |
| 257 | */␊ |
| 258 | ␊ |
| 259 | virtual UInt32 flush();␊ |
| 260 | ␊ |
| 261 | /*! @function lockFlush␊ |
| 262 | @abstract Frees all packets currently held in a synchronized queue and␊ |
| 263 | releases them back to the free mbuf pool.␊ |
| 264 | @discussion The size of the queue is cleared to zero. A spinlock is used␊ |
| 265 | to synchronize access to the queue.␊ |
| 266 | @result Returns the number of packets freed. ␊ |
| 267 | */␊ |
| 268 | ␊ |
| 269 | virtual UInt32 lockFlush();␊ |
| 270 | ␊ |
| 271 | // Virtual Pad functions␊ |
| 272 | OSMetaClassDeclareReservedUnused( IOPacketQueue, 0);␊ |
| 273 | OSMetaClassDeclareReservedUnused( IOPacketQueue, 1);␊ |
| 274 | OSMetaClassDeclareReservedUnused( IOPacketQueue, 2);␊ |
| 275 | OSMetaClassDeclareReservedUnused( IOPacketQueue, 3);␊ |
| 276 | OSMetaClassDeclareReservedUnused( IOPacketQueue, 4);␊ |
| 277 | OSMetaClassDeclareReservedUnused( IOPacketQueue, 5);␊ |
| 278 | OSMetaClassDeclareReservedUnused( IOPacketQueue, 6);␊ |
| 279 | OSMetaClassDeclareReservedUnused( IOPacketQueue, 7);␊ |
| 280 | OSMetaClassDeclareReservedUnused( IOPacketQueue, 8);␊ |
| 281 | OSMetaClassDeclareReservedUnused( IOPacketQueue, 9);␊ |
| 282 | OSMetaClassDeclareReservedUnused( IOPacketQueue, 10);␊ |
| 283 | OSMetaClassDeclareReservedUnused( IOPacketQueue, 11);␊ |
| 284 | OSMetaClassDeclareReservedUnused( IOPacketQueue, 12);␊ |
| 285 | OSMetaClassDeclareReservedUnused( IOPacketQueue, 13);␊ |
| 286 | OSMetaClassDeclareReservedUnused( IOPacketQueue, 14);␊ |
| 287 | OSMetaClassDeclareReservedUnused( IOPacketQueue, 15);␊ |
| 288 | };␊ |
| 289 | ␊ |
| 290 | #endif /* !_IOPACKETQUEUE_H */␊ |
| 291 | |
