src/mem/packet.hh

   1 /*
   2  * Copyright (c) 2006 The Regents of The University of Michigan
   3  * Copyright (c) 2010 Advanced Micro Devices, Inc.
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions are
   8  * met: redistributions of source code must retain the above copyright
   9  * notice, this list of conditions and the following disclaimer;
  10  * redistributions in binary form must reproduce the above copyright
  11  * notice, this list of conditions and the following disclaimer in the
  12  * documentation and/or other materials provided with the distribution;
  13  * neither the name of the copyright holders nor the names of its
  14  * contributors may be used to endorse or promote products derived from
  15  * this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  18  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  19  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  20  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  21  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  22  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  23  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  27  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28  *
  29  * Authors: Ron Dreslinski
  30  *          Steve Reinhardt
  31  *          Ali Saidi
  32  */
  33
  34 /**
  35  * @file
  36  * Declaration of the Packet class.
  37  */
  38
  39 #ifndef __MEM_PACKET_HH__
  40 #define __MEM_PACKET_HH__
  41
  42 #include <bitset>
  43 #include <cassert>
  44 #include <list>
  45
  46 #include "base/cast.hh"
  47 #include "base/compiler.hh"
  48 #include "base/fast_alloc.hh"
  49 #include "base/flags.hh"
  50 #include "base/misc.hh"
  51 #include "base/printable.hh"
  52 #include "base/types.hh"
  53 #include "mem/request.hh"
  54 #include "sim/core.hh"
  55
  56 struct Packet;
  57 typedef Packet *PacketPtr;
  58 typedef uint8_t* PacketDataPtr;
  59 typedef std::list<PacketPtr> PacketList;
  60
  61 class MemCmd
  62 {
  63     friend class Packet;
  64
  65   public:
  66     /**
  67      * List of all commands associated with a packet.
  68      */
  69     enum Command
  70     {
  71         InvalidCmd,
  72         ReadReq,
  73         ReadResp,
  74         ReadRespWithInvalidate,
  75         WriteReq,
  76         WriteResp,
  77         Writeback,
  78         SoftPFReq,
  79         HardPFReq,
  80         SoftPFResp,
  81         HardPFResp,
  82         WriteInvalidateReq,
  83         WriteInvalidateResp,
  84         UpgradeReq,
  85         SCUpgradeReq,           // Special "weak" upgrade for StoreCond
  86         UpgradeResp,
  87         SCUpgradeFailReq,       // Failed SCUpgradeReq in MSHR (never sent)
  88         UpgradeFailResp,        // Valid for SCUpgradeReq only
  89         ReadExReq,
  90         ReadExResp,
  91         LoadLockedReq,
  92         StoreCondReq,
  93         StoreCondFailReq,       // Failed StoreCondReq in MSHR (never sent)
  94         StoreCondResp,
  95         SwapReq,
  96         SwapResp,
  97         MessageReq,
  98         MessageResp,
  99         // Error responses
 100         // @TODO these should be classified as responses rather than
 101         // requests; coding them as requests initially for backwards
 102         // compatibility
 103         NetworkNackError,  // nacked at network layer (not by protocol)
 104         InvalidDestError,  // packet dest field invalid
 105         BadAddressError,   // memory address invalid
 106         // Fake simulator-only commands
 107         PrintReq,       // Print state matching address
 108         FlushReq,      //request for a cache flush
 109         NUM_MEM_CMDS
 110     };
 111
 112   private:
 113     /**
 114      * List of command attributes.
 115      */
 116     enum Attribute
 117     {
 118         IsRead,         //!< Data flows from responder to requester
 119         IsWrite,        //!< Data flows from requester to responder
 120         IsUpgrade,
 121         IsPrefetch,     //!< Not a demand access
 122         IsInvalidate,
 123         NeedsExclusive, //!< Requires exclusive copy to complete in-cache
 124         IsRequest,      //!< Issued by requester
 125         IsResponse,     //!< Issue by responder
 126         NeedsResponse,  //!< Requester needs response from target
 127         IsSWPrefetch,
 128         IsHWPrefetch,
 129         IsLlsc,         //!< Alpha/MIPS LL or SC access
 130         HasData,        //!< There is an associated payload
 131         IsError,        //!< Error response
 132         IsPrint,        //!< Print state matching address (for debugging)
 133         IsFlush,        //!< Flush the address from caches
 134         NUM_COMMAND_ATTRIBUTES
 135     };
 136
 137     /**
 138      * Structure that defines attributes and other data associated
 139      * with a Command.
 140      */
 141     struct CommandInfo
 142     {
 143         /// Set of attribute flags.
 144         const std::bitset<NUM_COMMAND_ATTRIBUTES> attributes;
 145         /// Corresponding response for requests; InvalidCmd if no
 146         /// response is applicable.
 147         const Command response;
 148         /// String representation (for printing)
 149         const std::string str;
 150     };
 151
 152     /// Array to map Command enum to associated info.
 153     static const CommandInfo commandInfo[];
 154
 155   private:
 156
 157     Command cmd;
 158
 159     bool
 160     testCmdAttrib(MemCmd::Attribute attrib) const
 161     {
 162         return commandInfo[cmd].attributes[attrib] != 0;
 163     }
 164
 165   public:
 166
 167     bool isRead() const         { return testCmdAttrib(IsRead); }
 168     bool isWrite() const        { return testCmdAttrib(IsWrite); }
 169     bool isUpgrade() const      { return testCmdAttrib(IsUpgrade); }
 170     bool isRequest() const      { return testCmdAttrib(IsRequest); }
 171     bool isResponse() const     { return testCmdAttrib(IsResponse); }
 172     bool needsExclusive() const { return testCmdAttrib(NeedsExclusive); }
 173     bool needsResponse() const  { return testCmdAttrib(NeedsResponse); }
 174     bool isInvalidate() const   { return testCmdAttrib(IsInvalidate); }
 175     bool hasData() const        { return testCmdAttrib(HasData); }
 176     bool isReadWrite() const    { return isRead() && isWrite(); }
 177     bool isLLSC() const         { return testCmdAttrib(IsLlsc); }
 178     bool isError() const        { return testCmdAttrib(IsError); }
 179     bool isPrint() const        { return testCmdAttrib(IsPrint); }
 180     bool isFlush() const        { return testCmdAttrib(IsFlush); }
 181
 182     const Command
 183     responseCommand() const
 184     {
 185         return commandInfo[cmd].response;
 186     }
 187
 188     /// Return the string to a cmd given by idx.
 189     const std::string &toString() const { return commandInfo[cmd].str; }
 190     int toInt() const { return (int)cmd; }
 191
 192     MemCmd(Command _cmd) : cmd(_cmd) { }
 193     MemCmd(int _cmd) : cmd((Command)_cmd) { }
 194     MemCmd() : cmd(InvalidCmd) { }
 195
 196     bool operator==(MemCmd c2) const { return (cmd == c2.cmd); }
 197     bool operator!=(MemCmd c2) const { return (cmd != c2.cmd); }
 198 };
 199
 200 /**
 201  * A Packet is used to encapsulate a transfer between two objects in
 202  * the memory system (e.g., the L1 and L2 cache).  (In contrast, a
 203  * single Request travels all the way from the requester to the
 204  * ultimate destination and back, possibly being conveyed by several
 205  * different Packets along the way.)
 206  */
 207 class Packet : public FastAlloc, public Printable
 208 {
 209   public:
 210     typedef uint32_t FlagsType;
 211     typedef ::Flags<FlagsType> Flags;
 212     typedef short NodeID;
 213
 214   private:
 215     static const FlagsType PUBLIC_FLAGS           = 0x00000000;
 216     static const FlagsType PRIVATE_FLAGS          = 0x00007F0F;
 217     static const FlagsType COPY_FLAGS             = 0x0000000F;
 218
 219     static const FlagsType SHARED                 = 0x00000001;
 220     // Special control flags
 221     /// Special timing-mode atomic snoop for multi-level coherence.
 222     static const FlagsType EXPRESS_SNOOP          = 0x00000002;
 223     /// Does supplier have exclusive copy?
 224     /// Useful for multi-level coherence.
 225     static const FlagsType SUPPLY_EXCLUSIVE       = 0x00000004;
 226     // Snoop response flags
 227     static const FlagsType MEM_INHIBIT            = 0x00000008;
 228     /// Are the 'addr' and 'size' fields valid?
 229     static const FlagsType VALID_ADDR             = 0x00000100;
 230     static const FlagsType VALID_SIZE             = 0x00000200;
 231     /// Is the 'src' field valid?
 232     static const FlagsType VALID_SRC              = 0x00000400;
 233     static const FlagsType VALID_DST              = 0x00000800;
 234     /// Is the data pointer set to a value that shouldn't be freed
 235     /// when the packet is destroyed?
 236     static const FlagsType STATIC_DATA            = 0x00001000;
 237     /// The data pointer points to a value that should be freed when
 238     /// the packet is destroyed.
 239     static const FlagsType DYNAMIC_DATA           = 0x00002000;
 240     /// the data pointer points to an array (thus delete []) needs to
 241     /// be called on it rather than simply delete.
 242     static const FlagsType ARRAY_DATA             = 0x00004000;
 243
 244     Flags flags;
 245
 246   public:
 247     typedef MemCmd::Command Command;
 248
 249     /// The command field of the packet.
 250     MemCmd cmd;
 251
 252     /// A pointer to the original request.
 253     RequestPtr req;
 254
 255   private:
 256    /**
 257     * A pointer to the data being transfered.  It can be differnt
 258     * sizes at each level of the heirarchy so it belongs in the
 259     * packet, not request. This may or may not be populated when a
 260     * responder recieves the packet. If not populated it memory should
 261     * be allocated.
 262     */
 263     PacketDataPtr data;
 264
 265     /// The address of the request.  This address could be virtual or
 266     /// physical, depending on the system configuration.
 267     Addr addr;
 268
 269     /// The size of the request or transfer.
 270     unsigned size;
 271
 272     /**
 273      * Device address (e.g., bus ID) of the source of the
 274      * transaction. The source is not responsible for setting this
 275      * field; it is set implicitly by the interconnect when the packet
 276      * is first sent.
 277      */
 278     NodeID src;
 279
 280     /**
 281      * Device address (e.g., bus ID) of the destination of the
 282      * transaction. The special value Broadcast indicates that the
 283      * packet should be routed based on its address. This field is
 284      * initialized in the constructor and is thus always valid (unlike
 285      * addr, size, and src).
 286      */
 287     NodeID dest;
 288
 289     /**
 290      * The original value of the command field.  Only valid when the
 291      * current command field is an error condition; in that case, the
 292      * previous contents of the command field are copied here.  This
 293      * field is *not* set on non-error responses.
 294      */
 295     MemCmd origCmd;
 296
 297   public:
 298     /// Used to calculate latencies for each packet.
 299     Tick time;
 300
 301     /// The time at which the packet will be fully transmitted
 302     Tick finishTime;
 303
 304     /// The time at which the first chunk of the packet will be transmitted
 305     Tick firstWordTime;
 306
 307     /// The special destination address indicating that the packet
 308     /// should be routed based on its address.
 309     static const NodeID Broadcast = -1;
 310
 311     /**
 312      * A virtual base opaque structure used to hold state associated
 313      * with the packet but specific to the sending device (e.g., an
 314      * MSHR).  A pointer to this state is returned in the packet's
 315      * response so that the sender can quickly look up the state
 316      * needed to process it.  A specific subclass would be derived
 317      * from this to carry state specific to a particular sending
 318      * device.
 319      */
 320     struct SenderState
 321     {
 322         virtual ~SenderState() {}
 323     };
 324
 325     /**
 326      * Object used to maintain state of a PrintReq.  The senderState
 327      * field of a PrintReq should always be of this type.
 328      */
 329     class PrintReqState : public SenderState, public FastAlloc
 330     {
 331       private:
 332         /**
 333          * An entry in the label stack.
 334          */
 335         struct LabelStackEntry
 336         {
 337             const std::string label;
 338             std::string *prefix;
 339             bool labelPrinted;
 340             LabelStackEntry(const std::string &_label, std::string *_prefix);
 341         };
 342
 343         typedef std::list<LabelStackEntry> LabelStack;
 344         LabelStack labelStack;
 345
 346         std::string *curPrefixPtr;
 347
 348       public:
 349         std::ostream &os;
 350         const int verbosity;
 351
 352         PrintReqState(std::ostream &os, int verbosity = 0);
 353         ~PrintReqState();
 354
 355         /**
 356          * Returns the current line prefix.
 357          */
 358         const std::string &curPrefix() { return *curPrefixPtr; }
 359
 360         /**
 361          * Push a label onto the label stack, and prepend the given
 362          * prefix string onto the current prefix.  Labels will only be
 363          * printed if an object within the label's scope is printed.
 364          */
 365         void pushLabel(const std::string &lbl,
 366                        const std::string &prefix = "  ");
 367
 368         /**
 369          * Pop a label off the label stack.
 370          */
 371         void popLabel();
 372
 373         /**
 374          * Print all of the pending unprinted labels on the
 375          * stack. Called by printObj(), so normally not called by
 376          * users unless bypassing printObj().
 377          */
 378         void printLabels();
 379
 380         /**
 381          * Print a Printable object to os, because it matched the
 382          * address on a PrintReq.
 383          */
 384         void printObj(Printable *obj);
 385     };
 386
 387     /**
 388      * This packet's sender state.  Devices should use dynamic_cast<>
 389      * to cast to the state appropriate to the sender.  The intent of
 390      * this variable is to allow a device to attach extra information
 391      * to a request.  A response packet must return the sender state
 392      * that was attached to the original request (even if a new packet
 393      * is created).
 394      */
 395     SenderState *senderState;
 396
 397     /// Return the string name of the cmd field (for debugging and
 398     /// tracing).
 399     const std::string &cmdString() const { return cmd.toString(); }
 400
 401     /// Return the index of this command.
 402     inline int cmdToIndex() const { return cmd.toInt(); }
 403
 404     bool isRead() const         { return cmd.isRead(); }
 405     bool isWrite() const        { return cmd.isWrite(); }
 406     bool isUpgrade()  const     { return cmd.isUpgrade(); }
 407     bool isRequest() const      { return cmd.isRequest(); }
 408     bool isResponse() const     { return cmd.isResponse(); }
 409     bool needsExclusive() const { return cmd.needsExclusive(); }
 410     bool needsResponse() const  { return cmd.needsResponse(); }
 411     bool isInvalidate() const   { return cmd.isInvalidate(); }
 412     bool hasData() const        { return cmd.hasData(); }
 413     bool isReadWrite() const    { return cmd.isReadWrite(); }
 414     bool isLLSC() const         { return cmd.isLLSC(); }
 415     bool isError() const        { return cmd.isError(); }
 416     bool isPrint() const        { return cmd.isPrint(); }
 417     bool isFlush() const        { return cmd.isFlush(); }
 418
 419     // Snoop flags
 420     void assertMemInhibit()     { flags.set(MEM_INHIBIT); }
 421     bool memInhibitAsserted()   { return flags.isSet(MEM_INHIBIT); }
 422     void assertShared()         { flags.set(SHARED); }
 423     bool sharedAsserted()       { return flags.isSet(SHARED); }
 424
 425     // Special control flags
 426     void setExpressSnoop()      { flags.set(EXPRESS_SNOOP); }
 427     bool isExpressSnoop()       { return flags.isSet(EXPRESS_SNOOP); }
 428     void setSupplyExclusive()   { flags.set(SUPPLY_EXCLUSIVE); }
 429     void clearSupplyExclusive() { flags.clear(SUPPLY_EXCLUSIVE); }
 430     bool isSupplyExclusive()    { return flags.isSet(SUPPLY_EXCLUSIVE); }
 431
 432     // Network error conditions... encapsulate them as methods since
 433     // their encoding keeps changing (from result field to command
 434     // field, etc.)
 435     void
 436     setNacked()
 437     {
 438         assert(isResponse());
 439         cmd = MemCmd::NetworkNackError;
 440     }
 441
 442     void
 443     setBadAddress()
 444     {
 445         assert(isResponse());
 446         cmd = MemCmd::BadAddressError;
 447     }
 448
 449     bool wasNacked() const     { return cmd == MemCmd::NetworkNackError; }
 450     bool hadBadAddress() const { return cmd == MemCmd::BadAddressError; }
 451     void copyError(Packet *pkt) { assert(pkt->isError()); cmd = pkt->cmd; }
 452
 453     bool isSrcValid() { return flags.isSet(VALID_SRC); }
 454     /// Accessor function to get the source index of the packet.
 455     NodeID getSrc() const    { assert(flags.isSet(VALID_SRC)); return src; }
 456     /// Accessor function to set the source index of the packet.
 457     void setSrc(NodeID _src) { src = _src; flags.set(VALID_SRC); }
 458     /// Reset source field, e.g. to retransmit packet on different bus.
 459     void clearSrc() { flags.clear(VALID_SRC); }
 460
 461     bool isDestValid() { return flags.isSet(VALID_DST); }
 462     /// Accessor function for the destination index of the packet.
 463     NodeID getDest() const     { assert(flags.isSet(VALID_DST)); return dest; }
 464     /// Accessor function to set the destination index of the packet.
 465     void setDest(NodeID _dest) { dest = _dest; flags.set(VALID_DST); }
 466
 467     Addr getAddr() const { assert(flags.isSet(VALID_ADDR)); return addr; }
 468     unsigned getSize() const  { assert(flags.isSet(VALID_SIZE)); return size; }
 469     Addr getOffset(int blkSize) const { return getAddr() & (Addr)(blkSize - 1); }
 470
 471     /**
 472      * It has been determined that the SC packet should successfully update
 473      * memory.  Therefore, convert this SC packet to a normal write.
 474      */
 475     void
 476     convertScToWrite()
 477     {
 478         assert(isLLSC());
 479         assert(isWrite());
 480         cmd = MemCmd::WriteReq;
 481     }
 482
 483     /**
 484      * When ruby is in use, Ruby will monitor the cache line and thus M5
 485      * phys memory should treat LL ops as normal reads.
 486      */
 487     void
 488     convertLlToRead()
 489     {
 490         assert(isLLSC());
 491         assert(isRead());
 492         cmd = MemCmd::ReadReq;
 493     }
 494
 495     /**
 496      * Constructor.  Note that a Request object must be constructed
 497      * first, but the Requests's physical address and size fields need
 498      * not be valid. The command and destination addresses must be
 499      * supplied.
 500      */
 501     Packet(Request *_req, MemCmd _cmd, NodeID _dest)
 502         :  flags(VALID_DST), cmd(_cmd), req(_req), data(NULL),
 503            dest(_dest), time(curTick()), senderState(NULL)
 504     {
 505         if (req->hasPaddr()) {
 506             addr = req->getPaddr();
 507             flags.set(VALID_ADDR);
 508         }
 509         if (req->hasSize()) {
 510             size = req->getSize();
 511             flags.set(VALID_SIZE);
 512         }
 513     }
 514
 515     /**
 516      * Alternate constructor if you are trying to create a packet with
 517      * a request that is for a whole block, not the address from the
 518      * req.  this allows for overriding the size/addr of the req.
 519      */
 520     Packet(Request *_req, MemCmd _cmd, NodeID _dest, int _blkSize)
 521         :  flags(VALID_DST), cmd(_cmd), req(_req), data(NULL),
 522            dest(_dest), time(curTick()), senderState(NULL)
 523     {
 524         if (req->hasPaddr()) {
 525             addr = req->getPaddr() & ~(_blkSize - 1);
 526             flags.set(VALID_ADDR);
 527         }
 528         size = _blkSize;
 529         flags.set(VALID_SIZE);
 530     }
 531
 532     /**
 533      * Alternate constructor for copying a packet.  Copy all fields
 534      * *except* if the original packet's data was dynamic, don't copy
 535      * that, as we can't guarantee that the new packet's lifetime is
 536      * less than that of the original packet.  In this case the new
 537      * packet should allocate its own data.
 538      */
 539     Packet(Packet *pkt, bool clearFlags = false)
 540         :  cmd(pkt->cmd), req(pkt->req),
 541            data(pkt->flags.isSet(STATIC_DATA) ? pkt->data : NULL),
 542            addr(pkt->addr), size(pkt->size), src(pkt->src), dest(pkt->dest),
 543            time(curTick()), senderState(pkt->senderState)
 544     {
 545         if (!clearFlags)
 546             flags.set(pkt->flags & COPY_FLAGS);
 547
 548         flags.set(pkt->flags & (VALID_ADDR|VALID_SIZE|VALID_SRC|VALID_DST));
 549         flags.set(pkt->flags & STATIC_DATA);
 550     }
 551
 552     /**
 553      * clean up packet variables
 554      */
 555     ~Packet()
 556     {
 557         // If this is a request packet for which there's no response,
 558         // delete the request object here, since the requester will
 559         // never get the chance.
 560         if (req && isRequest() && !needsResponse())
 561             delete req;
 562         deleteData();
 563     }
 564
 565     /**
 566      * Reinitialize packet address and size from the associated
 567      * Request object, and reset other fields that may have been
 568      * modified by a previous transaction.  Typically called when a
 569      * statically allocated Request/Packet pair is reused for multiple
 570      * transactions.
 571      */
 572     void
 573     reinitFromRequest()
 574     {
 575         assert(req->hasPaddr());
 576         flags = 0;
 577         addr = req->getPaddr();
 578         size = req->getSize();
 579         time = req->time();
 580
 581         flags.set(VALID_ADDR|VALID_SIZE);
 582         deleteData();
 583     }
 584
 585     /**
 586      * Take a request packet and modify it in place to be suitable for
 587      * returning as a response to that request.  The source and
 588      * destination fields are *not* modified, as is appropriate for
 589      * atomic accesses.
 590      */
 591     void
 592     makeResponse()
 593     {
 594         assert(needsResponse());
 595         assert(isRequest());
 596         origCmd = cmd;
 597         cmd = cmd.responseCommand();
 598
 599         // responses are never express, even if the snoop that
 600         // triggered them was
 601         flags.clear(EXPRESS_SNOOP);
 602
 603         dest = src;
 604         flags.set(VALID_DST, flags.isSet(VALID_SRC));
 605         flags.clear(VALID_SRC);
 606     }
 607
 608     void
 609     makeAtomicResponse()
 610     {
 611         makeResponse();
 612     }
 613
 614     void
 615     makeTimingResponse()
 616     {
 617         makeResponse();
 618     }
 619
 620     /**
 621      * Take a request packet that has been returned as NACKED and
 622      * modify it so that it can be sent out again. Only packets that
 623      * need a response can be NACKED, so verify that that is true.
 624      */
 625     void
 626     reinitNacked()
 627     {
 628         assert(wasNacked());
 629         cmd = origCmd;
 630         assert(needsResponse());
 631         setDest(Broadcast);
 632     }
 633
 634     void
 635     setSize(unsigned size)
 636     {
 637         assert(!flags.isSet(VALID_SIZE));
 638
 639         this->size = size;
 640         flags.set(VALID_SIZE);
 641     }
 642
 643
 644     /**
 645      * Set the data pointer to the following value that should not be
 646      * freed.
 647      */
 648     template <typename T>
 649     void
 650     dataStatic(T *p)
 651     {
 652         assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA|ARRAY_DATA));
 653         data = (PacketDataPtr)p;
 654         flags.set(STATIC_DATA);
 655     }
 656
 657     /**
 658      * Set the data pointer to a value that should have delete []
 659      * called on it.
 660      */
 661     template <typename T>
 662     void
 663     dataDynamicArray(T *p)
 664     {
 665         assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA|ARRAY_DATA));
 666         data = (PacketDataPtr)p;
 667         flags.set(DYNAMIC_DATA|ARRAY_DATA);
 668     }
 669
 670     /**
 671      * set the data pointer to a value that should have delete called
 672      * on it.
 673      */
 674     template <typename T>
 675     void
 676     dataDynamic(T *p)
 677     {
 678         assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA|ARRAY_DATA));
 679         data = (PacketDataPtr)p;
 680         flags.set(DYNAMIC_DATA);
 681     }
 682
 683     /**
 684      * get a pointer to the data ptr.
 685      */
 686     template <typename T>
 687     T*
 688     getPtr(bool null_ok = false)
 689     {
 690         assert(null_ok || flags.isSet(STATIC_DATA|DYNAMIC_DATA));
 691         return (T*)data;
 692     }
 693
 694     /**
 695      * return the value of what is pointed to in the packet.
 696      */
 697     template <typename T>
 698     T get();
 699
 700     /**
 701      * set the value in the data pointer to v.
 702      */
 703     template <typename T>
 704     void set(T v);
 705
 706     /**
 707      * Copy data into the packet from the provided pointer.
 708      */
 709     void
 710     setData(uint8_t *p)
 711     {
 712         if (p != getPtr<uint8_t>())
 713             std::memcpy(getPtr<uint8_t>(), p, getSize());
 714     }
 715
 716     /**
 717      * Copy data into the packet from the provided block pointer,
 718      * which is aligned to the given block size.
 719      */
 720     void
 721     setDataFromBlock(uint8_t *blk_data, int blkSize)
 722     {
 723         setData(blk_data + getOffset(blkSize));
 724     }
 725
 726     /**
 727      * Copy data from the packet to the provided block pointer, which
 728      * is aligned to the given block size.
 729      */
 730     void
 731     writeData(uint8_t *p)
 732     {
 733         std::memcpy(p, getPtr<uint8_t>(), getSize());
 734     }
 735
 736     /**
 737      * Copy data from the packet to the memory at the provided pointer.
 738      */
 739     void
 740     writeDataToBlock(uint8_t *blk_data, int blkSize)
 741     {
 742         writeData(blk_data + getOffset(blkSize));
 743     }
 744
 745     /**
 746      * delete the data pointed to in the data pointer. Ok to call to
 747      * matter how data was allocted.
 748      */
 749     void
 750     deleteData()
 751     {
 752         if (flags.isSet(ARRAY_DATA))
 753             delete [] data;
 754         else if (flags.isSet(DYNAMIC_DATA))
 755             delete data;
 756
 757         flags.clear(STATIC_DATA|DYNAMIC_DATA|ARRAY_DATA);
 758         data = NULL;
 759     }
 760
 761     /** If there isn't data in the packet, allocate some. */
 762     void
 763     allocate()
 764     {
 765         if (data) {
 766             assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
 767             return;
 768         }
 769
 770         assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
 771         flags.set(DYNAMIC_DATA|ARRAY_DATA);
 772         data = new uint8_t[getSize()];
 773     }
 774
 775     /**
 776      * Check a functional request against a memory value represented
 777      * by a base/size pair and an associated data array.  If the
 778      * functional request is a read, it may be satisfied by the memory
 779      * value.  If the functional request is a write, it may update the
 780      * memory value.
 781      */
 782     bool checkFunctional(Printable *obj, Addr base, int size, uint8_t *data);
 783
 784     /**
 785      * Check a functional request against a memory value stored in
 786      * another packet (i.e. an in-transit request or response).
 787      */
 788     bool
 789     checkFunctional(PacketPtr other)
 790     {
 791         uint8_t *data = other->hasData() ? other->getPtr<uint8_t>() : NULL;
 792         return checkFunctional(other, other->getAddr(), other->getSize(),
 793                                data);
 794     }
 795
 796     /**
 797      * Push label for PrintReq (safe to call unconditionally).
 798      */
 799     void
 800     pushLabel(const std::string &lbl)
 801     {
 802         if (isPrint())
 803             safe_cast<PrintReqState*>(senderState)->pushLabel(lbl);
 804     }
 805
 806     /**
 807      * Pop label for PrintReq (safe to call unconditionally).
 808      */
 809     void
 810     popLabel()
 811     {
 812         if (isPrint())
 813             safe_cast<PrintReqState*>(senderState)->popLabel();
 814     }
 815
 816     void print(std::ostream &o, int verbosity = 0,
 817                const std::string &prefix = "") const;
 818 };
 819
 820 #endif //__MEM_PACKET_HH