src/mem/packet.hh

   1 /*
   2  * Copyright (c) 2006 The Regents of The University of Michigan
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are
   7  * met: redistributions of source code must retain the above copyright
   8  * notice, this list of conditions and the following disclaimer;
   9  * redistributions in binary form must reproduce the above copyright
  10  * notice, this list of conditions and the following disclaimer in the
  11  * documentation and/or other materials provided with the distribution;
  12  * neither the name of the copyright holders nor the names of its
  13  * contributors may be used to endorse or promote products derived from
  14  * this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  17  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  18  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  19  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  20  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  21  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  22  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  26  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  *
  28  * Authors: Ron Dreslinski
  29  *          Steve Reinhardt
  30  *          Ali Saidi
  31  */
  32
  33 /**
  34  * @file
  35  * Declaration of the Packet class.
  36  */
  37
  38 #ifndef __MEM_PACKET_HH__
  39 #define __MEM_PACKET_HH__
  40
  41 #include <cassert>
  42 #include <list>
  43 #include <bitset>
  44
  45 #include "base/cast.hh"
  46 #include "base/compiler.hh"
  47 #include "base/fast_alloc.hh"
  48 #include "base/flags.hh"
  49 #include "base/misc.hh"
  50 #include "base/printable.hh"
  51 #include "base/types.hh"
  52 #include "mem/request.hh"
  53 #include "sim/core.hh"
  54
  55 struct Packet;
  56 typedef Packet *PacketPtr;
  57 typedef uint8_t* PacketDataPtr;
  58 typedef std::list<PacketPtr> PacketList;
  59
  60 class MemCmd
  61 {
  62     friend class Packet;
  63
  64   public:
  65     /**
  66      * List of all commands associated with a packet.
  67      */
  68     enum Command
  69     {
  70         InvalidCmd,
  71         ReadReq,
  72         ReadResp,
  73         ReadRespWithInvalidate,
  74         WriteReq,
  75         WriteResp,
  76         Writeback,
  77         SoftPFReq,
  78         HardPFReq,
  79         SoftPFResp,
  80         HardPFResp,
  81         WriteInvalidateReq,
  82         WriteInvalidateResp,
  83         UpgradeReq,
  84         UpgradeResp,
  85         ReadExReq,
  86         ReadExResp,
  87         LoadLockedReq,
  88         StoreCondReq,
  89         StoreCondResp,
  90         SwapReq,
  91         SwapResp,
  92         MessageReq,
  93         MessageResp,
  94         // Error responses
  95         // @TODO these should be classified as responses rather than
  96         // requests; coding them as requests initially for backwards
  97         // compatibility
  98         NetworkNackError,  // nacked at network layer (not by protocol)
  99         InvalidDestError,  // packet dest field invalid
 100         BadAddressError,   // memory address invalid
 101         // Fake simulator-only commands
 102         PrintReq,       // Print state matching address
 103         NUM_MEM_CMDS
 104     };
 105
 106   private:
 107     /**
 108      * List of command attributes.
 109      */
 110     enum Attribute
 111     {
 112         IsRead,         //!< Data flows from responder to requester
 113         IsWrite,        //!< Data flows from requester to responder
 114         IsPrefetch,     //!< Not a demand access
 115         IsInvalidate,
 116         NeedsExclusive, //!< Requires exclusive copy to complete in-cache
 117         IsRequest,      //!< Issued by requester
 118         IsResponse,     //!< Issue by responder
 119         NeedsResponse,  //!< Requester needs response from target
 120         IsSWPrefetch,
 121         IsHWPrefetch,
 122         IsLlsc,         //!< Alpha/MIPS LL or SC access
 123         HasData,        //!< There is an associated payload
 124         IsError,        //!< Error response
 125         IsPrint,        //!< Print state matching address (for debugging)
 126         NUM_COMMAND_ATTRIBUTES
 127     };
 128
 129     /**
 130      * Structure that defines attributes and other data associated
 131      * with a Command.
 132      */
 133     struct CommandInfo
 134     {
 135         /// Set of attribute flags.
 136         const std::bitset<NUM_COMMAND_ATTRIBUTES> attributes;
 137         /// Corresponding response for requests; InvalidCmd if no
 138         /// response is applicable.
 139         const Command response;
 140         /// String representation (for printing)
 141         const std::string str;
 142     };
 143
 144     /// Array to map Command enum to associated info.
 145     static const CommandInfo commandInfo[];
 146
 147   private:
 148
 149     Command cmd;
 150
 151     bool
 152     testCmdAttrib(MemCmd::Attribute attrib) const
 153     {
 154         return commandInfo[cmd].attributes[attrib] != 0;
 155     }
 156
 157   public:
 158
 159     bool isRead() const         { return testCmdAttrib(IsRead); }
 160     bool isWrite()  const       { return testCmdAttrib(IsWrite); }
 161     bool isRequest() const      { return testCmdAttrib(IsRequest); }
 162     bool isResponse() const     { return testCmdAttrib(IsResponse); }
 163     bool needsExclusive() const { return testCmdAttrib(NeedsExclusive); }
 164     bool needsResponse() const  { return testCmdAttrib(NeedsResponse); }
 165     bool isInvalidate() const   { return testCmdAttrib(IsInvalidate); }
 166     bool hasData() const        { return testCmdAttrib(HasData); }
 167     bool isReadWrite() const    { return isRead() && isWrite(); }
 168     bool isLLSC() const         { return testCmdAttrib(IsLlsc); }
 169     bool isError() const        { return testCmdAttrib(IsError); }
 170     bool isPrint() const        { return testCmdAttrib(IsPrint); }
 171
 172     const Command
 173     responseCommand() const
 174     {
 175         return commandInfo[cmd].response;
 176     }
 177
 178     /// Return the string to a cmd given by idx.
 179     const std::string &toString() const { return commandInfo[cmd].str; }
 180     int toInt() const { return (int)cmd; }
 181
 182     MemCmd(Command _cmd) : cmd(_cmd) { }
 183     MemCmd(int _cmd) : cmd((Command)_cmd) { }
 184     MemCmd() : cmd(InvalidCmd) { }
 185
 186     bool operator==(MemCmd c2) const { return (cmd == c2.cmd); }
 187     bool operator!=(MemCmd c2) const { return (cmd != c2.cmd); }
 188 };
 189
 190 /**
 191  * A Packet is used to encapsulate a transfer between two objects in
 192  * the memory system (e.g., the L1 and L2 cache).  (In contrast, a
 193  * single Request travels all the way from the requester to the
 194  * ultimate destination and back, possibly being conveyed by several
 195  * different Packets along the way.)
 196  */
 197 class Packet : public FastAlloc, public Printable
 198 {
 199   public:
 200     typedef uint32_t FlagsType;
 201     typedef ::Flags<FlagsType> Flags;
 202     typedef short NodeID;
 203
 204   private:
 205     static const FlagsType PUBLIC_FLAGS           = 0x00000000;
 206     static const FlagsType PRIVATE_FLAGS          = 0x00007F0F;
 207     static const FlagsType COPY_FLAGS             = 0x0000000F;
 208
 209     static const FlagsType SHARED                 = 0x00000001;
 210     // Special control flags
 211     /// Special timing-mode atomic snoop for multi-level coherence.
 212     static const FlagsType EXPRESS_SNOOP          = 0x00000002;
 213     /// Does supplier have exclusive copy?
 214     /// Useful for multi-level coherence.
 215     static const FlagsType SUPPLY_EXCLUSIVE       = 0x00000004;
 216     // Snoop response flags
 217     static const FlagsType MEM_INHIBIT            = 0x00000008;
 218     /// Are the 'addr' and 'size' fields valid?
 219     static const FlagsType VALID_ADDR             = 0x00000100;
 220     static const FlagsType VALID_SIZE             = 0x00000200;
 221     /// Is the 'src' field valid?
 222     static const FlagsType VALID_SRC              = 0x00000400;
 223     static const FlagsType VALID_DST              = 0x00000800;
 224     /// Is the data pointer set to a value that shouldn't be freed
 225     /// when the packet is destroyed?
 226     static const FlagsType STATIC_DATA            = 0x00001000;
 227     /// The data pointer points to a value that should be freed when
 228     /// the packet is destroyed.
 229     static const FlagsType DYNAMIC_DATA           = 0x00002000;
 230     /// the data pointer points to an array (thus delete []) needs to
 231     /// be called on it rather than simply delete.
 232     static const FlagsType ARRAY_DATA             = 0x00004000;
 233
 234     Flags flags;
 235
 236   public:
 237     typedef MemCmd::Command Command;
 238
 239     /// The command field of the packet.
 240     MemCmd cmd;
 241
 242     /// A pointer to the original request.
 243     RequestPtr req;
 244
 245   private:
 246    /**
 247     * A pointer to the data being transfered.  It can be differnt
 248     * sizes at each level of the heirarchy so it belongs in the
 249     * packet, not request. This may or may not be populated when a
 250     * responder recieves the packet. If not populated it memory should
 251     * be allocated.
 252     */
 253     PacketDataPtr data;
 254
 255     /// The address of the request.  This address could be virtual or
 256     /// physical, depending on the system configuration.
 257     Addr addr;
 258
 259     /// The size of the request or transfer.
 260     int size;
 261
 262     /**
 263      * Device address (e.g., bus ID) of the source of the
 264      * transaction. The source is not responsible for setting this
 265      * field; it is set implicitly by the interconnect when the packet
 266      * is first sent.
 267      */
 268     NodeID src;
 269
 270     /**
 271      * Device address (e.g., bus ID) of the destination of the
 272      * transaction. The special value Broadcast indicates that the
 273      * packet should be routed based on its address. This field is
 274      * initialized in the constructor and is thus always valid (unlike
 275      * addr, size, and src).
 276      */
 277     NodeID dest;
 278
 279     /**
 280      * The original value of the command field.  Only valid when the
 281      * current command field is an error condition; in that case, the
 282      * previous contents of the command field are copied here.  This
 283      * field is *not* set on non-error responses.
 284      */
 285     MemCmd origCmd;
 286
 287   public:
 288     /// Used to calculate latencies for each packet.
 289     Tick time;
 290
 291     /// The time at which the packet will be fully transmitted
 292     Tick finishTime;
 293
 294     /// The time at which the first chunk of the packet will be transmitted
 295     Tick firstWordTime;
 296
 297     /// The special destination address indicating that the packet
 298     /// should be routed based on its address.
 299     static const NodeID Broadcast = -1;
 300
 301     /**
 302      * A virtual base opaque structure used to hold state associated
 303      * with the packet but specific to the sending device (e.g., an
 304      * MSHR).  A pointer to this state is returned in the packet's
 305      * response so that the sender can quickly look up the state
 306      * needed to process it.  A specific subclass would be derived
 307      * from this to carry state specific to a particular sending
 308      * device.
 309      */
 310     struct SenderState
 311     {
 312         virtual ~SenderState() {}
 313     };
 314
 315     /**
 316      * Object used to maintain state of a PrintReq.  The senderState
 317      * field of a PrintReq should always be of this type.
 318      */
 319     class PrintReqState : public SenderState, public FastAlloc
 320     {
 321       private:
 322         /**
 323          * An entry in the label stack.
 324          */
 325         struct LabelStackEntry
 326         {
 327             const std::string label;
 328             std::string *prefix;
 329             bool labelPrinted;
 330             LabelStackEntry(const std::string &_label, std::string *_prefix);
 331         };
 332
 333         typedef std::list<LabelStackEntry> LabelStack;
 334         LabelStack labelStack;
 335
 336         std::string *curPrefixPtr;
 337
 338       public:
 339         std::ostream &os;
 340         const int verbosity;
 341
 342         PrintReqState(std::ostream &os, int verbosity = 0);
 343         ~PrintReqState();
 344
 345         /**
 346          * Returns the current line prefix.
 347          */
 348         const std::string &curPrefix() { return *curPrefixPtr; }
 349
 350         /**
 351          * Push a label onto the label stack, and prepend the given
 352          * prefix string onto the current prefix.  Labels will only be
 353          * printed if an object within the label's scope is printed.
 354          */
 355         void pushLabel(const std::string &lbl,
 356                        const std::string &prefix = "  ");
 357
 358         /**
 359          * Pop a label off the label stack.
 360          */
 361         void popLabel();
 362
 363         /**
 364          * Print all of the pending unprinted labels on the
 365          * stack. Called by printObj(), so normally not called by
 366          * users unless bypassing printObj().
 367          */
 368         void printLabels();
 369
 370         /**
 371          * Print a Printable object to os, because it matched the
 372          * address on a PrintReq.
 373          */
 374         void printObj(Printable *obj);
 375     };
 376
 377     /**
 378      * This packet's sender state.  Devices should use dynamic_cast<>
 379      * to cast to the state appropriate to the sender.  The intent of
 380      * this variable is to allow a device to attach extra information
 381      * to a request.  A response packet must return the sender state
 382      * that was attached to the original request (even if a new packet
 383      * is created).
 384      */
 385     SenderState *senderState;
 386
 387     /// Return the string name of the cmd field (for debugging and
 388     /// tracing).
 389     const std::string &cmdString() const { return cmd.toString(); }
 390
 391     /// Return the index of this command.
 392     inline int cmdToIndex() const { return cmd.toInt(); }
 393
 394     bool isRead() const         { return cmd.isRead(); }
 395     bool isWrite()  const       { return cmd.isWrite(); }
 396     bool isRequest() const      { return cmd.isRequest(); }
 397     bool isResponse() const     { return cmd.isResponse(); }
 398     bool needsExclusive() const { return cmd.needsExclusive(); }
 399     bool needsResponse() const  { return cmd.needsResponse(); }
 400     bool isInvalidate() const   { return cmd.isInvalidate(); }
 401     bool hasData() const        { return cmd.hasData(); }
 402     bool isReadWrite() const    { return cmd.isReadWrite(); }
 403     bool isLLSC() const         { return cmd.isLLSC(); }
 404     bool isError() const        { return cmd.isError(); }
 405     bool isPrint() const        { return cmd.isPrint(); }
 406
 407     // Snoop flags
 408     void assertMemInhibit()     { flags.set(MEM_INHIBIT); }
 409     bool memInhibitAsserted()   { return flags.isSet(MEM_INHIBIT); }
 410     void assertShared()         { flags.set(SHARED); }
 411     bool sharedAsserted()       { return flags.isSet(SHARED); }
 412
 413     // Special control flags
 414     void setExpressSnoop()      { flags.set(EXPRESS_SNOOP); }
 415     bool isExpressSnoop()       { return flags.isSet(EXPRESS_SNOOP); }
 416     void setSupplyExclusive()   { flags.set(SUPPLY_EXCLUSIVE); }
 417     bool isSupplyExclusive()    { return flags.isSet(SUPPLY_EXCLUSIVE); }
 418
 419     // Network error conditions... encapsulate them as methods since
 420     // their encoding keeps changing (from result field to command
 421     // field, etc.)
 422     void
 423     setNacked()
 424     {
 425         assert(isResponse());
 426         cmd = MemCmd::NetworkNackError;
 427     }
 428
 429     void
 430     setBadAddress()
 431     {
 432         assert(isResponse());
 433         cmd = MemCmd::BadAddressError;
 434     }
 435
 436     bool wasNacked() const     { return cmd == MemCmd::NetworkNackError; }
 437     bool hadBadAddress() const { return cmd == MemCmd::BadAddressError; }
 438     void copyError(Packet *pkt) { assert(pkt->isError()); cmd = pkt->cmd; }
 439
 440     /// Accessor function to get the source index of the packet.
 441     NodeID getSrc() const    { assert(flags.isSet(VALID_SRC)); return src; }
 442     /// Accessor function to set the source index of the packet.
 443     void setSrc(NodeID _src) { src = _src; flags.set(VALID_SRC); }
 444     /// Reset source field, e.g. to retransmit packet on different bus.
 445     void clearSrc() { flags.clear(VALID_SRC); }
 446
 447     /// Accessor function for the destination index of the packet.
 448     NodeID getDest() const     { assert(flags.isSet(VALID_DST)); return dest; }
 449     /// Accessor function to set the destination index of the packet.
 450     void setDest(NodeID _dest) { dest = _dest; flags.set(VALID_DST); }
 451
 452     Addr getAddr() const { assert(flags.isSet(VALID_ADDR)); return addr; }
 453     int getSize() const  { assert(flags.isSet(VALID_SIZE)); return size; }
 454     Addr getOffset(int blkSize) const { return getAddr() & (Addr)(blkSize - 1); }
 455
 456     /**
 457      * Constructor.  Note that a Request object must be constructed
 458      * first, but the Requests's physical address and size fields need
 459      * not be valid. The command and destination addresses must be
 460      * supplied.
 461      */
 462     Packet(Request *_req, MemCmd _cmd, NodeID _dest)
 463         :  flags(VALID_DST), cmd(_cmd), req(_req), data(NULL),
 464            dest(_dest), time(curTick), senderState(NULL)
 465     {
 466         if (req->hasPaddr()) {
 467             addr = req->getPaddr();
 468             flags.set(VALID_ADDR);
 469         }
 470         if (req->hasSize()) {
 471             size = req->getSize();
 472             flags.set(VALID_SIZE);
 473         }
 474     }
 475
 476     /**
 477      * Alternate constructor if you are trying to create a packet with
 478      * a request that is for a whole block, not the address from the
 479      * req.  this allows for overriding the size/addr of the req.
 480      */
 481     Packet(Request *_req, MemCmd _cmd, NodeID _dest, int _blkSize)
 482         :  flags(VALID_DST), cmd(_cmd), req(_req), data(NULL),
 483            dest(_dest), time(curTick), senderState(NULL)
 484     {
 485         if (req->hasPaddr()) {
 486             addr = req->getPaddr() & ~(_blkSize - 1);
 487             flags.set(VALID_ADDR);
 488         }
 489         size = _blkSize;
 490         flags.set(VALID_SIZE);
 491     }
 492
 493     /**
 494      * Alternate constructor for copying a packet.  Copy all fields
 495      * *except* if the original packet's data was dynamic, don't copy
 496      * that, as we can't guarantee that the new packet's lifetime is
 497      * less than that of the original packet.  In this case the new
 498      * packet should allocate its own data.
 499      */
 500     Packet(Packet *pkt, bool clearFlags = false)
 501         :  cmd(pkt->cmd), req(pkt->req),
 502            data(pkt->flags.isSet(STATIC_DATA) ? pkt->data : NULL),
 503            addr(pkt->addr), size(pkt->size), src(pkt->src), dest(pkt->dest),
 504            time(curTick), senderState(pkt->senderState)
 505     {
 506         if (!clearFlags)
 507             flags.set(pkt->flags & COPY_FLAGS);
 508
 509         flags.set(pkt->flags & (VALID_ADDR|VALID_SIZE|VALID_SRC|VALID_DST));
 510         flags.set(pkt->flags & STATIC_DATA);
 511     }
 512
 513     /**
 514      * clean up packet variables
 515      */
 516     ~Packet()
 517     {
 518         // If this is a request packet for which there's no response,
 519         // delete the request object here, since the requester will
 520         // never get the chance.
 521         if (req && isRequest() && !needsResponse())
 522             delete req;
 523         deleteData();
 524     }
 525
 526     /**
 527      * Reinitialize packet address and size from the associated
 528      * Request object, and reset other fields that may have been
 529      * modified by a previous transaction.  Typically called when a
 530      * statically allocated Request/Packet pair is reused for multiple
 531      * transactions.
 532      */
 533     void
 534     reinitFromRequest()
 535     {
 536         assert(req->hasPaddr());
 537         flags = 0;
 538         addr = req->getPaddr();
 539         size = req->getSize();
 540         time = req->time();
 541
 542         flags.set(VALID_ADDR|VALID_SIZE);
 543         deleteData();
 544     }
 545
 546     /**
 547      * Take a request packet and modify it in place to be suitable for
 548      * returning as a response to that request.  The source and
 549      * destination fields are *not* modified, as is appropriate for
 550      * atomic accesses.
 551      */
 552     void
 553     makeResponse()
 554     {
 555         assert(needsResponse());
 556         assert(isRequest());
 557         origCmd = cmd;
 558         cmd = cmd.responseCommand();
 559
 560         dest = src;
 561         flags.set(VALID_DST, flags.isSet(VALID_SRC));
 562         flags.clear(VALID_SRC);
 563     }
 564
 565     void
 566     makeAtomicResponse()
 567     {
 568         makeResponse();
 569     }
 570
 571     void
 572     makeTimingResponse()
 573     {
 574         makeResponse();
 575     }
 576
 577     /**
 578      * Take a request packet that has been returned as NACKED and
 579      * modify it so that it can be sent out again. Only packets that
 580      * need a response can be NACKED, so verify that that is true.
 581      */
 582     void
 583     reinitNacked()
 584     {
 585         assert(wasNacked());
 586         cmd = origCmd;
 587         assert(needsResponse());
 588         setDest(Broadcast);
 589     }
 590
 591
 592     /**
 593      * Set the data pointer to the following value that should not be
 594      * freed.
 595      */
 596     template <typename T>
 597     void
 598     dataStatic(T *p)
 599     {
 600         assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA|ARRAY_DATA));
 601         data = (PacketDataPtr)p;
 602         flags.set(STATIC_DATA);
 603     }
 604
 605     /**
 606      * Set the data pointer to a value that should have delete []
 607      * called on it.
 608      */
 609     template <typename T>
 610     void
 611     dataDynamicArray(T *p)
 612     {
 613         assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA|ARRAY_DATA));
 614         data = (PacketDataPtr)p;
 615         flags.set(DYNAMIC_DATA|ARRAY_DATA);
 616     }
 617
 618     /**
 619      * set the data pointer to a value that should have delete called
 620      * on it.
 621      */
 622     template <typename T>
 623     void
 624     dataDynamic(T *p)
 625     {
 626         assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA|ARRAY_DATA));
 627         data = (PacketDataPtr)p;
 628         flags.set(DYNAMIC_DATA);
 629     }
 630
 631     /**
 632      * get a pointer to the data ptr.
 633      */
 634     template <typename T>
 635     T*
 636     getPtr()
 637     {
 638         assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
 639         return (T*)data;
 640     }
 641
 642     /**
 643      * return the value of what is pointed to in the packet.
 644      */
 645     template <typename T>
 646     T get();
 647
 648     /**
 649      * set the value in the data pointer to v.
 650      */
 651     template <typename T>
 652     void set(T v);
 653
 654     /**
 655      * Copy data into the packet from the provided pointer.
 656      */
 657     void
 658     setData(uint8_t *p)
 659     {
 660         std::memcpy(getPtr<uint8_t>(), p, getSize());
 661     }
 662
 663     /**
 664      * Copy data into the packet from the provided block pointer,
 665      * which is aligned to the given block size.
 666      */
 667     void
 668     setDataFromBlock(uint8_t *blk_data, int blkSize)
 669     {
 670         setData(blk_data + getOffset(blkSize));
 671     }
 672
 673     /**
 674      * Copy data from the packet to the provided block pointer, which
 675      * is aligned to the given block size.
 676      */
 677     void
 678     writeData(uint8_t *p)
 679     {
 680         std::memcpy(p, getPtr<uint8_t>(), getSize());
 681     }
 682
 683     /**
 684      * Copy data from the packet to the memory at the provided pointer.
 685      */
 686     void
 687     writeDataToBlock(uint8_t *blk_data, int blkSize)
 688     {
 689         writeData(blk_data + getOffset(blkSize));
 690     }
 691
 692     /**
 693      * delete the data pointed to in the data pointer. Ok to call to
 694      * matter how data was allocted.
 695      */
 696     void
 697     deleteData()
 698     {
 699         if (flags.isSet(ARRAY_DATA))
 700             delete [] data;
 701         else if (flags.isSet(DYNAMIC_DATA))
 702             delete data;
 703
 704         flags.clear(STATIC_DATA|DYNAMIC_DATA|ARRAY_DATA);
 705         data = NULL;
 706     }
 707
 708     /** If there isn't data in the packet, allocate some. */
 709     void
 710     allocate()
 711     {
 712         if (data) {
 713             assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
 714             return;
 715         }
 716
 717         assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
 718         flags.set(DYNAMIC_DATA|ARRAY_DATA);
 719         data = new uint8_t[getSize()];
 720     }
 721
 722
 723     /**
 724      * Check a functional request against a memory value represented
 725      * by a base/size pair and an associated data array.  If the
 726      * functional request is a read, it may be satisfied by the memory
 727      * value.  If the functional request is a write, it may update the
 728      * memory value.
 729      */
 730     bool checkFunctional(Printable *obj, Addr base, int size, uint8_t *data);
 731
 732     /**
 733      * Check a functional request against a memory value stored in
 734      * another packet (i.e. an in-transit request or response).
 735      */
 736     bool
 737     checkFunctional(PacketPtr other)
 738     {
 739         uint8_t *data = other->hasData() ? other->getPtr<uint8_t>() : NULL;
 740         return checkFunctional(other, other->getAddr(), other->getSize(),
 741                                data);
 742     }
 743
 744     /**
 745      * Push label for PrintReq (safe to call unconditionally).
 746      */
 747     void
 748     pushLabel(const std::string &lbl)
 749     {
 750         if (isPrint())
 751             safe_cast<PrintReqState*>(senderState)->pushLabel(lbl);
 752     }
 753
 754     /**
 755      * Pop label for PrintReq (safe to call unconditionally).
 756      */
 757     void
 758     popLabel()
 759     {
 760         if (isPrint())
 761             safe_cast<PrintReqState*>(senderState)->popLabel();
 762     }
 763
 764     void print(std::ostream &o, int verbosity = 0,
 765                const std::string &prefix = "") const;
 766 };
 767
 768 #endif //__MEM_PACKET_HH