src/rx/rx_rdwr.c

   1  /*
   2   * Copyright 2000, International Business Machines Corporation and others.
   3   * All Rights Reserved.
   4   *
   5   * This software has been released under the terms of the IBM Public
   6   * License.  For details, see the LICENSE file in the top-level source
   7   * directory or online at http://www.openafs.org/dl/license10.html
   8   */
   9
  10 #include <afsconfig.h>
  11 #include <afs/param.h>
  12
  13 #ifdef KERNEL
  14 # ifndef UKERNEL
  15 #  ifdef RX_KERNEL_TRACE
  16 #   include "rx_kcommon.h"
  17 #  endif
  18 #  if defined(AFS_DARWIN_ENV) || defined(AFS_XBSD_ENV)
  19 #   include "afs/sysincludes.h"
  20 #  else
  21 #   include "h/types.h"
  22 #   include "h/time.h"
  23 #   include "h/stat.h"
  24 #   if defined(AFS_AIX_ENV) || defined(AFS_AUX_ENV) || defined(AFS_SUN5_ENV)
  25 #    include "h/systm.h"
  26 #   endif
  27 #   ifdef       AFS_OSF_ENV
  28 #    include <net/net_globals.h>
  29 #   endif /* AFS_OSF_ENV */
  30 #   ifdef AFS_LINUX20_ENV
  31 #    include "h/socket.h"
  32 #   endif
  33 #   include "netinet/in.h"
  34 #   if defined(AFS_SGI_ENV)
  35 #    include "afs/sysincludes.h"
  36 #   endif
  37 #  endif
  38 #  include "afs/afs_args.h"
  39 #  if   (defined(AFS_AUX_ENV) || defined(AFS_AIX_ENV))
  40 #   include "h/systm.h"
  41 #  endif
  42 # else /* !UKERNEL */
  43 #  include "afs/sysincludes.h"
  44 # endif /* !UKERNEL */
  45
  46 # ifdef RXDEBUG
  47 #  undef RXDEBUG                        /* turn off debugging */
  48 # endif /* RXDEBUG */
  49
  50 # include "afs/afs_osi.h"
  51 # include "rx_kmutex.h"
  52 # include "rx/rx_kernel.h"
  53 # include "afs/lock.h"
  54 #else /* KERNEL */
  55 # include <roken.h>
  56 # include <afs/opr.h>
  57 #endif /* KERNEL */
  58
  59 #include "rx.h"
  60 #include "rx_clock.h"
  61 #include "rx_globals.h"
  62 #include "rx_atomic.h"
  63 #include "rx_internal.h"
  64 #include "rx_conn.h"
  65 #include "rx_call.h"
  66 #include "rx_packet.h"
  67
  68 #ifdef RX_LOCKS_DB
  69 /* rxdb_fileID is used to identify the lock location, along with line#. */
  70 static int rxdb_fileID = RXDB_FILE_RX_RDWR;
  71 #endif /* RX_LOCKS_DB */
  72
  73 /* Get the next packet in the receive queue
  74  *
  75  * Dispose of the call's currentPacket, and move the next packet in the
  76  * receive queue into the currentPacket field. If the next packet isn't
  77  * available, then currentPacket is left NULL.
  78  *
  79  * @param call
  80  *      The RX call to manipulate
  81  * @returns
  82  *      0 on success, an error code on failure
  83  *
  84  * @notes
  85  *      Must be called with the call locked. Unlocks the call if returning
  86  *      with an error.
  87  */
  88
  89 static int
  90 rxi_GetNextPacket(struct rx_call *call) {
  91     struct rx_packet *rp;
  92     int error;
  93
  94     if (call->currentPacket != NULL) {
  95 #ifdef RX_TRACK_PACKETS
  96         call->currentPacket->flags |= RX_PKTFLAG_CP;
  97 #endif
  98         rxi_FreePacket(call->currentPacket);
  99         call->currentPacket = NULL;
 100     }
 101
 102     if (opr_queue_IsEmpty(&call->rq))
 103         return 0;
 104
 105     /* Check that next packet available is next in sequence */
 106     rp = opr_queue_First(&call->rq, struct rx_packet, entry);
 107     if (rp->header.seq != call->rnext)
 108         return 0;
 109
 110     opr_queue_Remove(&rp->entry);
 111 #ifdef RX_TRACK_PACKETS
 112     rp->flags &= ~RX_PKTFLAG_RQ;
 113 #endif
 114 #ifdef RXDEBUG_PACKET
 115     call->rqc--;
 116 #endif /* RXDEBUG_PACKET */
 117
 118     /* RXS_CheckPacket called to undo RXS_PreparePacket's work.  It may
 119      * reduce the length of the packet by up to conn->maxTrailerSize,
 120      * to reflect the length of the data + the header. */
 121     if ((error = RXS_CheckPacket(call->conn->securityObject, call, rp))) {
 122         /* Used to merely shut down the call, but now we shut down the whole
 123          * connection since this may indicate an attempt to hijack it */
 124
 125         MUTEX_EXIT(&call->lock);
 126         rxi_ConnectionError(call->conn, error);
 127         MUTEX_ENTER(&call->conn->conn_data_lock);
 128         rp = rxi_SendConnectionAbort(call->conn, rp, 0, 0);
 129         MUTEX_EXIT(&call->conn->conn_data_lock);
 130         rxi_FreePacket(rp);
 131
 132         return error;
 133      }
 134
 135     call->rnext++;
 136     call->currentPacket = rp;
 137 #ifdef RX_TRACK_PACKETS
 138     call->currentPacket->flags |= RX_PKTFLAG_CP;
 139 #endif
 140     call->curvec = 1;   /* 0th vec is always header */
 141
 142     /* begin at the beginning [ more or less ], continue on until the end,
 143      * then stop. */
 144     call->curpos = (char *)call->currentPacket->wirevec[1].iov_base +
 145                    call->conn->securityHeaderSize;
 146     call->curlen = call->currentPacket->wirevec[1].iov_len -
 147                    call->conn->securityHeaderSize;
 148
 149     call->nLeft = call->currentPacket->length;
 150     call->bytesRcvd += call->currentPacket->length;
 151
 152     call->nHardAcks++;
 153
 154     return 0;
 155 }
 156
 157 /* rxi_ReadProc -- internal version.
 158  *
 159  * LOCKS USED -- called at netpri
 160  */
 161 int
 162 rxi_ReadProc(struct rx_call *call, char *buf,
 163              int nbytes)
 164 {
 165     int requestCount;
 166     int code;
 167     unsigned int t;
 168
 169 /* XXXX took out clock_NewTime from here.  Was it needed? */
 170     requestCount = nbytes;
 171
 172     /* Free any packets from the last call to ReadvProc/WritevProc */
 173     if (!opr_queue_IsEmpty(&call->iovq)) {
 174 #ifdef RXDEBUG_PACKET
 175         call->iovqc -=
 176 #endif /* RXDEBUG_PACKET */
 177             rxi_FreePackets(0, &call->iovq);
 178     }
 179
 180     do {
 181         if (call->nLeft == 0) {
 182             /* Get next packet */
 183             MUTEX_ENTER(&call->lock);
 184             for (;;) {
 185                 if (call->error || (call->mode != RX_MODE_RECEIVING)) {
 186                     if (call->error) {
 187                         call->mode = RX_MODE_ERROR;
 188                         MUTEX_EXIT(&call->lock);
 189                         return 0;
 190                     }
 191                     if (call->mode == RX_MODE_SENDING) {
 192                         MUTEX_EXIT(&call->lock);
 193                         rxi_FlushWrite(call);
 194                         MUTEX_ENTER(&call->lock);
 195                         continue;
 196                     }
 197                 }
 198
 199                 code = rxi_GetNextPacket(call);
 200                 if (code)
 201                      return 0;
 202
 203                 if (call->currentPacket) {
 204                     if (!(call->flags & RX_CALL_RECEIVE_DONE)) {
 205                         if (call->nHardAcks > (u_short) rxi_HardAckRate) {
 206                             rxevent_Cancel(&call->delayedAckEvent, call,
 207                                            RX_CALL_REFCOUNT_DELAY);
 208                             rxi_SendAck(call, 0, 0, RX_ACK_DELAY, 0);
 209                         } else {
 210                             /* Delay to consolidate ack packets */
 211                             rxi_PostDelayedAckEvent(call, &rx_hardAckDelay);
 212                         }
 213                     }
 214                     break;
 215                 }
 216
 217                 /*
 218                  * If we reach this point either we have no packets in the
 219                  * receive queue or the next packet in the queue is not the
 220                  * one we are looking for.  There is nothing else for us to
 221                  * do but wait for another packet to arrive.
 222                  */
 223
 224                 /* Are there ever going to be any more packets? */
 225                 if (call->flags & RX_CALL_RECEIVE_DONE) {
 226                     MUTEX_EXIT(&call->lock);
 227                     return requestCount - nbytes;
 228                 }
 229                 /* Wait for in-sequence packet */
 230                 call->flags |= RX_CALL_READER_WAIT;
 231                 clock_NewTime();
 232                 call->startWait = clock_Sec();
 233                 while (call->flags & RX_CALL_READER_WAIT) {
 234 #ifdef  RX_ENABLE_LOCKS
 235                     CV_WAIT(&call->cv_rq, &call->lock);
 236 #else
 237                     osi_rxSleep(&call->rq);
 238 #endif
 239                 }
 240
 241                 call->startWait = 0;
 242 #ifdef RX_ENABLE_LOCKS
 243                 if (call->error) {
 244                     MUTEX_EXIT(&call->lock);
 245                     return 0;
 246                 }
 247 #endif /* RX_ENABLE_LOCKS */
 248             }
 249             MUTEX_EXIT(&call->lock);
 250         } else
 251             /* osi_Assert(cp); */
 252             /* MTUXXX  this should be replaced by some error-recovery code before shipping */
 253             /* yes, the following block is allowed to be the ELSE clause (or not) */
 254             /* It's possible for call->nLeft to be smaller than any particular
 255              * iov_len.  Usually, recvmsg doesn't change the iov_len, since it
 256              * reflects the size of the buffer.  We have to keep track of the
 257              * number of bytes read in the length field of the packet struct.  On
 258              * the final portion of a received packet, it's almost certain that
 259              * call->nLeft will be smaller than the final buffer. */
 260             while (nbytes && call->currentPacket) {
 261                 t = MIN((int)call->curlen, nbytes);
 262                 t = MIN(t, (int)call->nLeft);
 263                 memcpy(buf, call->curpos, t);
 264                 buf += t;
 265                 nbytes -= t;
 266                 call->curpos += t;
 267                 call->curlen -= t;
 268                 call->nLeft -= t;
 269
 270                 if (!call->nLeft) {
 271                     /* out of packet.  Get another one. */
 272 #ifdef RX_TRACK_PACKETS
 273                     call->currentPacket->flags &= ~RX_PKTFLAG_CP;
 274 #endif
 275                     rxi_FreePacket(call->currentPacket);
 276                     call->currentPacket = NULL;
 277                 } else if (!call->curlen) {
 278                     /* need to get another struct iov */
 279                     if (++call->curvec >= call->currentPacket->niovecs) {
 280                         /* current packet is exhausted, get ready for another */
 281                         /* don't worry about curvec and stuff, they get set somewhere else */
 282 #ifdef RX_TRACK_PACKETS
 283                         call->currentPacket->flags &= ~RX_PKTFLAG_CP;
 284 #endif
 285                         rxi_FreePacket(call->currentPacket);
 286                         call->currentPacket = NULL;
 287                         call->nLeft = 0;
 288                     } else {
 289                         call->curpos =
 290                             call->currentPacket->wirevec[call->curvec].iov_base;
 291                         call->curlen =
 292                             call->currentPacket->wirevec[call->curvec].iov_len;
 293                     }
 294                 }
 295             }
 296         if (!nbytes) {
 297             /* user buffer is full, return */
 298             return requestCount;
 299         }
 300
 301     } while (nbytes);
 302
 303     return requestCount;
 304 }
 305
 306 int
 307 rx_ReadProc(struct rx_call *call, char *buf, int nbytes)
 308 {
 309     int bytes;
 310     SPLVAR;
 311
 312     /* Free any packets from the last call to ReadvProc/WritevProc */
 313     if (!opr_queue_IsEmpty(&call->iovq)) {
 314 #ifdef RXDEBUG_PACKET
 315         call->iovqc -=
 316 #endif /* RXDEBUG_PACKET */
 317             rxi_FreePackets(0, &call->iovq);
 318     }
 319
 320     /*
 321      * Most common case, all of the data is in the current iovec.
 322      * We are relying on nLeft being zero unless the call is in receive mode.
 323      */
 324     if (!call->error && call->curlen > nbytes && call->nLeft > nbytes) {
 325         memcpy(buf, call->curpos, nbytes);
 326
 327         call->curpos += nbytes;
 328         call->curlen -= nbytes;
 329         call->nLeft  -= nbytes;
 330
 331         if (!call->nLeft && call->currentPacket != NULL) {
 332             /* out of packet.  Get another one. */
 333             rxi_FreePacket(call->currentPacket);
 334             call->currentPacket = (struct rx_packet *)0;
 335         }
 336         return nbytes;
 337     }
 338
 339     NETPRI;
 340     bytes = rxi_ReadProc(call, buf, nbytes);
 341     USERPRI;
 342     return bytes;
 343 }
 344
 345 /* Optimization for unmarshalling 32 bit integers */
 346 int
 347 rx_ReadProc32(struct rx_call *call, afs_int32 * value)
 348 {
 349     int bytes;
 350     SPLVAR;
 351
 352     /* Free any packets from the last call to ReadvProc/WritevProc */
 353     if (!opr_queue_IsEmpty(&call->iovq)) {
 354 #ifdef RXDEBUG_PACKET
 355         call->iovqc -=
 356 #endif /* RXDEBUG_PACKET */
 357             rxi_FreePackets(0, &call->iovq);
 358     }
 359
 360     /*
 361      * Most common case, all of the data is in the current iovec.
 362      * We are relying on nLeft being zero unless the call is in receive mode.
 363      */
 364     if (!call->error && call->curlen >= sizeof(afs_int32)
 365         && call->nLeft >= sizeof(afs_int32)) {
 366
 367         memcpy((char *)value, call->curpos, sizeof(afs_int32));
 368
 369         call->curpos += sizeof(afs_int32);
 370         call->curlen -= sizeof(afs_int32);
 371         call->nLeft  -= sizeof(afs_int32);
 372
 373         if (!call->nLeft && call->currentPacket != NULL) {
 374             /* out of packet.  Get another one. */
 375             rxi_FreePacket(call->currentPacket);
 376             call->currentPacket = (struct rx_packet *)0;
 377         }
 378         return sizeof(afs_int32);
 379     }
 380
 381     NETPRI;
 382     bytes = rxi_ReadProc(call, (char *)value, sizeof(afs_int32));
 383     USERPRI;
 384
 385     return bytes;
 386 }
 387
 388 /* rxi_FillReadVec
 389  *
 390  * Uses packets in the receive queue to fill in as much of the
 391  * current iovec as possible. Does not block if it runs out
 392  * of packets to complete the iovec. Return true if an ack packet
 393  * was sent, otherwise return false */
 394 int
 395 rxi_FillReadVec(struct rx_call *call, afs_uint32 serial)
 396 {
 397     int didConsume = 0;
 398     int didHardAck = 0;
 399     int code;
 400     unsigned int t;
 401     struct iovec *call_iov;
 402     struct iovec *cur_iov = NULL;
 403
 404     if (call->currentPacket) {
 405         cur_iov = &call->currentPacket->wirevec[call->curvec];
 406     }
 407     call_iov = &call->iov[call->iovNext];
 408
 409     while (!call->error && call->iovNBytes && call->iovNext < call->iovMax) {
 410         if (call->nLeft == 0) {
 411             /* Get next packet */
 412             code = rxi_GetNextPacket(call);
 413             if (code) {
 414                 MUTEX_ENTER(&call->lock);
 415                 return 1;
 416             }
 417
 418             if (call->currentPacket) {
 419                 cur_iov = &call->currentPacket->wirevec[1];
 420                 didConsume = 1;
 421                 continue;
 422             } else {
 423                 break;
 424             }
 425         }
 426
 427         /* It's possible for call->nLeft to be smaller than any particular
 428          * iov_len.  Usually, recvmsg doesn't change the iov_len, since it
 429          * reflects the size of the buffer.  We have to keep track of the
 430          * number of bytes read in the length field of the packet struct.  On
 431          * the final portion of a received packet, it's almost certain that
 432          * call->nLeft will be smaller than the final buffer. */
 433         while (call->iovNBytes
 434                && call->iovNext < call->iovMax
 435                && call->currentPacket) {
 436
 437             t = MIN((int)call->curlen, call->iovNBytes);
 438             t = MIN(t, (int)call->nLeft);
 439             call_iov->iov_base = call->curpos;
 440             call_iov->iov_len = t;
 441             call_iov++;
 442             call->iovNext++;
 443             call->iovNBytes -= t;
 444             call->curpos += t;
 445             call->curlen -= t;
 446             call->nLeft -= t;
 447
 448             if (!call->nLeft) {
 449                 /* out of packet.  Get another one. */
 450 #ifdef RX_TRACK_PACKETS
 451                 call->currentPacket->flags &= ~RX_PKTFLAG_CP;
 452                 call->currentPacket->flags |= RX_PKTFLAG_IOVQ;
 453 #endif
 454                 opr_queue_Append(&call->iovq, &call->currentPacket->entry);
 455 #ifdef RXDEBUG_PACKET
 456                 call->iovqc++;
 457 #endif /* RXDEBUG_PACKET */
 458                 call->currentPacket = NULL;
 459             } else if (!call->curlen) {
 460                 /* need to get another struct iov */
 461                 if (++call->curvec >= call->currentPacket->niovecs) {
 462                     /* current packet is exhausted, get ready for another */
 463                     /* don't worry about curvec and stuff, they get set somewhere else */
 464 #ifdef RX_TRACK_PACKETS
 465                     call->currentPacket->flags &= ~RX_PKTFLAG_CP;
 466                     call->currentPacket->flags |= RX_PKTFLAG_IOVQ;
 467 #endif
 468                     opr_queue_Append(&call->iovq, &call->currentPacket->entry);
 469 #ifdef RXDEBUG_PACKET
 470                     call->iovqc++;
 471 #endif /* RXDEBUG_PACKET */
 472                     call->currentPacket = NULL;
 473                     call->nLeft = 0;
 474                 } else {
 475                     cur_iov++;
 476                     call->curpos = (char *)cur_iov->iov_base;
 477                     call->curlen = cur_iov->iov_len;
 478                 }
 479             }
 480         }
 481     }
 482
 483     /* If we consumed any packets then check whether we need to
 484      * send a hard ack. */
 485     if (didConsume && (!(call->flags & RX_CALL_RECEIVE_DONE))) {
 486         if (call->nHardAcks > (u_short) rxi_HardAckRate) {
 487             rxevent_Cancel(&call->delayedAckEvent, call,
 488                            RX_CALL_REFCOUNT_DELAY);
 489             rxi_SendAck(call, 0, serial, RX_ACK_DELAY, 0);
 490             didHardAck = 1;
 491         } else {
 492             /* Delay to consolidate ack packets */
 493             rxi_PostDelayedAckEvent(call, &rx_hardAckDelay);
 494         }
 495     }
 496     return didHardAck;
 497 }
 498
 499
 500 /* rxi_ReadvProc -- internal version.
 501  *
 502  * Fills in an iovec with pointers to the packet buffers. All packets
 503  * except the last packet (new current packet) are moved to the iovq
 504  * while the application is processing the data.
 505  *
 506  * LOCKS USED -- called at netpri.
 507  */
 508 int
 509 rxi_ReadvProc(struct rx_call *call, struct iovec *iov, int *nio, int maxio,
 510               int nbytes)
 511 {
 512     int bytes;
 513
 514     /* Free any packets from the last call to ReadvProc/WritevProc */
 515     if (!opr_queue_IsEmpty(&call->iovq)) {
 516 #ifdef RXDEBUG_PACKET
 517         call->iovqc -=
 518 #endif /* RXDEBUG_PACKET */
 519             rxi_FreePackets(0, &call->iovq);
 520     }
 521
 522     if (call->mode == RX_MODE_SENDING) {
 523         rxi_FlushWrite(call);
 524     }
 525
 526     MUTEX_ENTER(&call->lock);
 527     if (call->error)
 528         goto error;
 529
 530     /* Get whatever data is currently available in the receive queue.
 531      * If rxi_FillReadVec sends an ack packet then it is possible
 532      * that we will receive more data while we drop the call lock
 533      * to send the packet. Set the RX_CALL_IOVEC_WAIT flag
 534      * here to avoid a race with the receive thread if we send
 535      * hard acks in rxi_FillReadVec. */
 536     call->flags |= RX_CALL_IOVEC_WAIT;
 537     call->iovNBytes = nbytes;
 538     call->iovMax = maxio;
 539     call->iovNext = 0;
 540     call->iov = iov;
 541     rxi_FillReadVec(call, 0);
 542
 543     /* if we need more data then sleep until the receive thread has
 544      * filled in the rest. */
 545     if (!call->error && call->iovNBytes && call->iovNext < call->iovMax
 546         && !(call->flags & RX_CALL_RECEIVE_DONE)) {
 547         call->flags |= RX_CALL_READER_WAIT;
 548         clock_NewTime();
 549         call->startWait = clock_Sec();
 550         while (call->flags & RX_CALL_READER_WAIT) {
 551 #ifdef  RX_ENABLE_LOCKS
 552             CV_WAIT(&call->cv_rq, &call->lock);
 553 #else
 554             osi_rxSleep(&call->rq);
 555 #endif
 556         }
 557         call->startWait = 0;
 558     }
 559     call->flags &= ~RX_CALL_IOVEC_WAIT;
 560
 561     if (call->error)
 562         goto error;
 563
 564     call->iov = NULL;
 565     *nio = call->iovNext;
 566     bytes = nbytes - call->iovNBytes;
 567     MUTEX_EXIT(&call->lock);
 568     return bytes;
 569
 570   error:
 571     MUTEX_EXIT(&call->lock);
 572     call->mode = RX_MODE_ERROR;
 573     return 0;
 574 }
 575
 576 int
 577 rx_ReadvProc(struct rx_call *call, struct iovec *iov, int *nio, int maxio,
 578              int nbytes)
 579 {
 580     int bytes;
 581     SPLVAR;
 582
 583     NETPRI;
 584     bytes = rxi_ReadvProc(call, iov, nio, maxio, nbytes);
 585     USERPRI;
 586     return bytes;
 587 }
 588
 589 /* rxi_WriteProc -- internal version.
 590  *
 591  * LOCKS USED -- called at netpri
 592  */
 593
 594 int
 595 rxi_WriteProc(struct rx_call *call, char *buf,
 596               int nbytes)
 597 {
 598     struct rx_connection *conn = call->conn;
 599     unsigned int t;
 600     int requestCount = nbytes;
 601
 602     /* Free any packets from the last call to ReadvProc/WritevProc */
 603     if (!opr_queue_IsEmpty(&call->iovq)) {
 604 #ifdef RXDEBUG_PACKET
 605         call->iovqc -=
 606 #endif /* RXDEBUG_PACKET */
 607             rxi_FreePackets(0, &call->iovq);
 608     }
 609
 610     if (call->mode != RX_MODE_SENDING) {
 611         if ((conn->type == RX_SERVER_CONNECTION)
 612             && (call->mode == RX_MODE_RECEIVING)) {
 613             call->mode = RX_MODE_SENDING;
 614             if (call->currentPacket) {
 615 #ifdef RX_TRACK_PACKETS
 616                 call->currentPacket->flags &= ~RX_PKTFLAG_CP;
 617 #endif
 618                 rxi_FreePacket(call->currentPacket);
 619                 call->currentPacket = NULL;
 620                 call->nLeft = 0;
 621                 call->nFree = 0;
 622             }
 623         } else {
 624             return 0;
 625         }
 626     }
 627
 628     /* Loop condition is checked at end, so that a write of 0 bytes
 629      * will force a packet to be created--specially for the case where
 630      * there are 0 bytes on the stream, but we must send a packet
 631      * anyway. */
 632     do {
 633         if (call->nFree == 0) {
 634             MUTEX_ENTER(&call->lock);
 635             if (call->error)
 636                 call->mode = RX_MODE_ERROR;
 637             if (!call->error && call->currentPacket) {
 638                 clock_NewTime();        /* Bogus:  need new time package */
 639                 /* The 0, below, specifies that it is not the last packet:
 640                  * there will be others. PrepareSendPacket may
 641                  * alter the packet length by up to
 642                  * conn->securityMaxTrailerSize */
 643                 call->bytesSent += call->currentPacket->length;
 644                 rxi_PrepareSendPacket(call, call->currentPacket, 0);
 645 #ifdef  AFS_GLOBAL_RXLOCK_KERNEL
 646                 /* PrepareSendPacket drops the call lock */
 647                 rxi_WaitforTQBusy(call);
 648 #endif /* AFS_GLOBAL_RXLOCK_KERNEL */
 649 #ifdef RX_TRACK_PACKETS
 650                 call->currentPacket->flags |= RX_PKTFLAG_TQ;
 651 #endif
 652                 opr_queue_Append(&call->tq, &call->currentPacket->entry);
 653 #ifdef RXDEBUG_PACKET
 654                 call->tqc++;
 655 #endif /* RXDEBUG_PACKET */
 656 #ifdef RX_TRACK_PACKETS
 657                 call->currentPacket->flags &= ~RX_PKTFLAG_CP;
 658 #endif
 659                 call->currentPacket = NULL;
 660
 661                 /* If the call is in recovery, let it exhaust its current
 662                  * retransmit queue before forcing it to send new packets
 663                  */
 664                 if (!(call->flags & (RX_CALL_FAST_RECOVER))) {
 665                     rxi_Start(call, 0);
 666                 }
 667             } else if (call->currentPacket) {
 668 #ifdef RX_TRACK_PACKETS
 669                 call->currentPacket->flags &= ~RX_PKTFLAG_CP;
 670 #endif
 671                 rxi_FreePacket(call->currentPacket);
 672                 call->currentPacket = NULL;
 673             }
 674             /* Wait for transmit window to open up */
 675             while (!call->error
 676                    && call->tnext + 1 > call->tfirst + (2 * call->twind)) {
 677                 clock_NewTime();
 678                 call->startWait = clock_Sec();
 679
 680 #ifdef  RX_ENABLE_LOCKS
 681                 CV_WAIT(&call->cv_twind, &call->lock);
 682 #else
 683                 call->flags |= RX_CALL_WAIT_WINDOW_ALLOC;
 684                 osi_rxSleep(&call->twind);
 685 #endif
 686
 687                 call->startWait = 0;
 688 #ifdef RX_ENABLE_LOCKS
 689                 if (call->error) {
 690                     call->mode = RX_MODE_ERROR;
 691                     MUTEX_EXIT(&call->lock);
 692                     return 0;
 693                 }
 694 #endif /* RX_ENABLE_LOCKS */
 695             }
 696             if ((call->currentPacket = rxi_AllocSendPacket(call, nbytes))) {
 697 #ifdef RX_TRACK_PACKETS
 698                 call->currentPacket->flags |= RX_PKTFLAG_CP;
 699 #endif
 700                 call->nFree = call->currentPacket->length;
 701                 call->curvec = 1;       /* 0th vec is always header */
 702                 /* begin at the beginning [ more or less ], continue
 703                  * on until the end, then stop. */
 704                 call->curpos =
 705                     (char *) call->currentPacket->wirevec[1].iov_base +
 706                     call->conn->securityHeaderSize;
 707                 call->curlen =
 708                     call->currentPacket->wirevec[1].iov_len -
 709                     call->conn->securityHeaderSize;
 710             }
 711             if (call->error) {
 712                 call->mode = RX_MODE_ERROR;
 713                 if (call->currentPacket) {
 714 #ifdef RX_TRACK_PACKETS
 715                     call->currentPacket->flags &= ~RX_PKTFLAG_CP;
 716 #endif
 717                     rxi_FreePacket(call->currentPacket);
 718                     call->currentPacket = NULL;
 719                 }
 720                 MUTEX_EXIT(&call->lock);
 721                 return 0;
 722             }
 723             MUTEX_EXIT(&call->lock);
 724         }
 725
 726         if (call->currentPacket && (int)call->nFree < nbytes) {
 727             /* Try to extend the current buffer */
 728             int len, mud;
 729             len = call->currentPacket->length;
 730             mud = rx_MaxUserDataSize(call);
 731             if (mud > len) {
 732                 int want;
 733                 want = MIN(nbytes - (int)call->nFree, mud - len);
 734                 rxi_AllocDataBuf(call->currentPacket, want,
 735                                  RX_PACKET_CLASS_SEND_CBUF);
 736                 if (call->currentPacket->length > (unsigned)mud)
 737                     call->currentPacket->length = mud;
 738                 call->nFree += (call->currentPacket->length - len);
 739             }
 740         }
 741
 742         /* If the remaining bytes fit in the buffer, then store them
 743          * and return.  Don't ship a buffer that's full immediately to
 744          * the peer--we don't know if it's the last buffer yet */
 745
 746         if (!call->currentPacket) {
 747             call->nFree = 0;
 748         }
 749
 750         while (nbytes && call->nFree) {
 751
 752             t = MIN((int)call->curlen, nbytes);
 753             t = MIN((int)call->nFree, t);
 754             memcpy(call->curpos, buf, t);
 755             buf += t;
 756             nbytes -= t;
 757             call->curpos += t;
 758             call->curlen -= (u_short)t;
 759             call->nFree -= (u_short)t;
 760
 761             if (!call->curlen) {
 762                 /* need to get another struct iov */
 763                 if (++call->curvec >= call->currentPacket->niovecs) {
 764                     /* current packet is full, extend or send it */
 765                     call->nFree = 0;
 766                 } else {
 767                     call->curpos =
 768                         call->currentPacket->wirevec[call->curvec].iov_base;
 769                     call->curlen =
 770                         call->currentPacket->wirevec[call->curvec].iov_len;
 771                 }
 772             }
 773         }                       /* while bytes to send and room to send them */
 774
 775         /* might be out of space now */
 776         if (!nbytes) {
 777             return requestCount;
 778         } else;                 /* more data to send, so get another packet and keep going */
 779     } while (nbytes);
 780
 781     return requestCount - nbytes;
 782 }
 783
 784 int
 785 rx_WriteProc(struct rx_call *call, char *buf, int nbytes)
 786 {
 787     int bytes;
 788     int tcurlen;
 789     int tnFree;
 790     char *tcurpos;
 791     SPLVAR;
 792
 793     /* Free any packets from the last call to ReadvProc/WritevProc */
 794     if (!opr_queue_IsEmpty(&call->iovq)) {
 795 #ifdef RXDEBUG_PACKET
 796         call->iovqc -=
 797 #endif /* RXDEBUG_PACKET */
 798             rxi_FreePackets(0, &call->iovq);
 799     }
 800
 801     /*
 802      * Most common case: all of the data fits in the current iovec.
 803      * We are relying on nFree being zero unless the call is in send mode.
 804      */
 805     tcurlen = (int)call->curlen;
 806     tnFree = (int)call->nFree;
 807     if (!call->error && tcurlen >= nbytes && tnFree >= nbytes) {
 808         tcurpos = call->curpos;
 809
 810         memcpy(tcurpos, buf, nbytes);
 811         call->curpos = tcurpos + nbytes;
 812         call->curlen = (u_short)(tcurlen - nbytes);
 813         call->nFree = (u_short)(tnFree - nbytes);
 814         return nbytes;
 815     }
 816
 817     NETPRI;
 818     bytes = rxi_WriteProc(call, buf, nbytes);
 819     USERPRI;
 820     return bytes;
 821 }
 822
 823 /* Optimization for marshalling 32 bit arguments */
 824 int
 825 rx_WriteProc32(struct rx_call *call, afs_int32 * value)
 826 {
 827     int bytes;
 828     int tcurlen;
 829     int tnFree;
 830     char *tcurpos;
 831     SPLVAR;
 832
 833     if (!opr_queue_IsEmpty(&call->iovq)) {
 834 #ifdef RXDEBUG_PACKET
 835         call->iovqc -=
 836 #endif /* RXDEBUG_PACKET */
 837             rxi_FreePackets(0, &call->iovq);
 838     }
 839
 840     /*
 841      * Most common case: all of the data fits in the current iovec.
 842      * We are relying on nFree being zero unless the call is in send mode.
 843      */
 844     tcurlen = call->curlen;
 845     tnFree = call->nFree;
 846     if (!call->error && tcurlen >= sizeof(afs_int32)
 847         && tnFree >= sizeof(afs_int32)) {
 848         tcurpos = call->curpos;
 849
 850         if (!((size_t)tcurpos & (sizeof(afs_int32) - 1))) {
 851             *((afs_int32 *) (tcurpos)) = *value;
 852         } else {
 853             memcpy(tcurpos, (char *)value, sizeof(afs_int32));
 854         }
 855         call->curpos = tcurpos + sizeof(afs_int32);
 856         call->curlen = (u_short)(tcurlen - sizeof(afs_int32));
 857         call->nFree = (u_short)(tnFree - sizeof(afs_int32));
 858         return sizeof(afs_int32);
 859     }
 860
 861     NETPRI;
 862     bytes = rxi_WriteProc(call, (char *)value, sizeof(afs_int32));
 863     USERPRI;
 864     return bytes;
 865 }
 866
 867 /* rxi_WritevAlloc -- internal version.
 868  *
 869  * Fill in an iovec to point to data in packet buffers. The application
 870  * calls rxi_WritevProc when the buffers are full.
 871  *
 872  * LOCKS USED -- called at netpri.
 873  */
 874
 875 static int
 876 rxi_WritevAlloc(struct rx_call *call, struct iovec *iov, int *nio, int maxio,
 877                 int nbytes)
 878 {
 879     struct rx_connection *conn = call->conn;
 880     struct rx_packet *cp;
 881     int requestCount;
 882     int nextio;
 883     /* Temporary values, real work is done in rxi_WritevProc */
 884     int tnFree;
 885     unsigned int tcurvec;
 886     char *tcurpos;
 887     int tcurlen;
 888
 889     requestCount = nbytes;
 890     nextio = 0;
 891
 892     /* Free any packets from the last call to ReadvProc/WritevProc */
 893     if (!opr_queue_IsEmpty(&call->iovq)) {
 894 #ifdef RXDEBUG_PACKET
 895         call->iovqc -=
 896 #endif /* RXDEBUG_PACKET */
 897             rxi_FreePackets(0, &call->iovq);
 898     }
 899
 900     if (call->mode != RX_MODE_SENDING) {
 901         if ((conn->type == RX_SERVER_CONNECTION)
 902             && (call->mode == RX_MODE_RECEIVING)) {
 903             call->mode = RX_MODE_SENDING;
 904             if (call->currentPacket) {
 905 #ifdef RX_TRACK_PACKETS
 906                 call->currentPacket->flags &= ~RX_PKTFLAG_CP;
 907 #endif
 908                 rxi_FreePacket(call->currentPacket);
 909                 call->currentPacket = NULL;
 910                 call->nLeft = 0;
 911                 call->nFree = 0;
 912             }
 913         } else {
 914             return 0;
 915         }
 916     }
 917
 918     /* Set up the iovec to point to data in packet buffers. */
 919     tnFree = call->nFree;
 920     tcurvec = call->curvec;
 921     tcurpos = call->curpos;
 922     tcurlen = call->curlen;
 923     cp = call->currentPacket;
 924     do {
 925         int t;
 926
 927         if (tnFree == 0) {
 928             /* current packet is full, allocate a new one */
 929             MUTEX_ENTER(&call->lock);
 930             cp = rxi_AllocSendPacket(call, nbytes);
 931             MUTEX_EXIT(&call->lock);
 932             if (cp == NULL) {
 933                 /* out of space, return what we have */
 934                 *nio = nextio;
 935                 return requestCount - nbytes;
 936             }
 937 #ifdef RX_TRACK_PACKETS
 938             cp->flags |= RX_PKTFLAG_IOVQ;
 939 #endif
 940             opr_queue_Append(&call->iovq, &cp->entry);
 941 #ifdef RXDEBUG_PACKET
 942             call->iovqc++;
 943 #endif /* RXDEBUG_PACKET */
 944             tnFree = cp->length;
 945             tcurvec = 1;
 946             tcurpos =
 947                 (char *)cp->wirevec[1].iov_base +
 948                 call->conn->securityHeaderSize;
 949             tcurlen = cp->wirevec[1].iov_len - call->conn->securityHeaderSize;
 950         }
 951
 952         if (tnFree < nbytes) {
 953             /* try to extend the current packet */
 954             int len, mud;
 955             len = cp->length;
 956             mud = rx_MaxUserDataSize(call);
 957             if (mud > len) {
 958                 int want;
 959                 want = MIN(nbytes - tnFree, mud - len);
 960                 rxi_AllocDataBuf(cp, want, RX_PACKET_CLASS_SEND_CBUF);
 961                 if (cp->length > (unsigned)mud)
 962                     cp->length = mud;
 963                 tnFree += (cp->length - len);
 964                 if (cp == call->currentPacket) {
 965                     call->nFree += (cp->length - len);
 966                 }
 967             }
 968         }
 969
 970         /* fill in the next entry in the iovec */
 971         t = MIN(tcurlen, nbytes);
 972         t = MIN(tnFree, t);
 973         iov[nextio].iov_base = tcurpos;
 974         iov[nextio].iov_len = t;
 975         nbytes -= t;
 976         tcurpos += t;
 977         tcurlen -= t;
 978         tnFree -= t;
 979         nextio++;
 980
 981         if (!tcurlen) {
 982             /* need to get another struct iov */
 983             if (++tcurvec >= cp->niovecs) {
 984                 /* current packet is full, extend it or move on to next packet */
 985                 tnFree = 0;
 986             } else {
 987                 tcurpos = (char *)cp->wirevec[tcurvec].iov_base;
 988                 tcurlen = cp->wirevec[tcurvec].iov_len;
 989             }
 990         }
 991     } while (nbytes && nextio < maxio);
 992     *nio = nextio;
 993     return requestCount - nbytes;
 994 }
 995
 996 int
 997 rx_WritevAlloc(struct rx_call *call, struct iovec *iov, int *nio, int maxio,
 998                int nbytes)
 999 {
1000     int bytes;
1001     SPLVAR;
1002
1003     NETPRI;
1004     bytes = rxi_WritevAlloc(call, iov, nio, maxio, nbytes);
1005     USERPRI;
1006     return bytes;
1007 }
1008
1009 /* rxi_WritevProc -- internal version.
1010  *
1011  * Send buffers allocated in rxi_WritevAlloc.
1012  *
1013  * LOCKS USED -- called at netpri.
1014  */
1015 int
1016 rxi_WritevProc(struct rx_call *call, struct iovec *iov, int nio, int nbytes)
1017 {
1018 #ifdef RX_TRACK_PACKETS
1019     struct opr_queue *cursor;
1020 #endif
1021     int nextio;
1022     int requestCount;
1023     struct opr_queue tmpq;
1024 #ifdef RXDEBUG_PACKET
1025     u_short tmpqc;
1026 #endif
1027
1028     requestCount = nbytes;
1029     nextio = 0;
1030
1031     MUTEX_ENTER(&call->lock);
1032     if (call->error) {
1033         call->mode = RX_MODE_ERROR;
1034     } else if (call->mode != RX_MODE_SENDING) {
1035         call->error = RX_PROTOCOL_ERROR;
1036     }
1037 #ifdef AFS_GLOBAL_RXLOCK_KERNEL
1038     rxi_WaitforTQBusy(call);
1039 #endif /* AFS_GLOBAL_RXLOCK_KERNEL */
1040
1041     if (call->error) {
1042         call->mode = RX_MODE_ERROR;
1043         MUTEX_EXIT(&call->lock);
1044         if (call->currentPacket) {
1045 #ifdef RX_TRACK_PACKETS
1046             call->currentPacket->flags &= ~RX_PKTFLAG_CP;
1047             call->currentPacket->flags |= RX_PKTFLAG_IOVQ;
1048 #endif
1049             opr_queue_Prepend(&call->iovq, &call->currentPacket->entry);
1050 #ifdef RXDEBUG_PACKET
1051             call->iovqc++;
1052 #endif /* RXDEBUG_PACKET */
1053             call->currentPacket = NULL;
1054         }
1055 #ifdef RXDEBUG_PACKET
1056         call->iovqc -=
1057 #endif /* RXDEBUG_PACKET */
1058             rxi_FreePackets(0, &call->iovq);
1059         return 0;
1060     }
1061
1062     /* Loop through the I/O vector adjusting packet pointers.
1063      * Place full packets back onto the iovq once they are ready
1064      * to send. Set RX_PROTOCOL_ERROR if any problems are found in
1065      * the iovec. We put the loop condition at the end to ensure that
1066      * a zero length write will push a short packet. */
1067     nextio = 0;
1068     opr_queue_Init(&tmpq);
1069 #ifdef RXDEBUG_PACKET
1070     tmpqc = 0;
1071 #endif /* RXDEBUG_PACKET */
1072     do {
1073         if (call->nFree == 0 && call->currentPacket) {
1074             clock_NewTime();    /* Bogus:  need new time package */
1075             /* The 0, below, specifies that it is not the last packet:
1076              * there will be others. PrepareSendPacket may
1077              * alter the packet length by up to
1078              * conn->securityMaxTrailerSize */
1079             call->bytesSent += call->currentPacket->length;
1080             rxi_PrepareSendPacket(call, call->currentPacket, 0);
1081 #ifdef  AFS_GLOBAL_RXLOCK_KERNEL
1082             /* PrepareSendPacket drops the call lock */
1083             rxi_WaitforTQBusy(call);
1084 #endif /* AFS_GLOBAL_RXLOCK_KERNEL */
1085             opr_queue_Append(&tmpq, &call->currentPacket->entry);
1086 #ifdef RXDEBUG_PACKET
1087             tmpqc++;
1088 #endif /* RXDEBUG_PACKET */
1089             call->currentPacket = NULL;
1090
1091             /* The head of the iovq is now the current packet */
1092             if (nbytes) {
1093                 if (opr_queue_IsEmpty(&call->iovq)) {
1094                     MUTEX_EXIT(&call->lock);
1095                     call->error = RX_PROTOCOL_ERROR;
1096 #ifdef RXDEBUG_PACKET
1097                     tmpqc -=
1098 #endif /* RXDEBUG_PACKET */
1099                         rxi_FreePackets(0, &tmpq);
1100                     return 0;
1101                 }
1102                 call->currentPacket = opr_queue_First(&call->iovq,
1103                                                       struct rx_packet,
1104                                                       entry);
1105                 opr_queue_Remove(&call->currentPacket->entry);
1106 #ifdef RX_TRACK_PACKETS
1107                 call->currentPacket->flags &= ~RX_PKTFLAG_IOVQ;
1108                 call->currentPacket->flags |= RX_PKTFLAG_CP;
1109 #endif
1110 #ifdef RXDEBUG_PACKET
1111                 call->iovqc--;
1112 #endif /* RXDEBUG_PACKET */
1113                 call->nFree = call->currentPacket->length;
1114                 call->curvec = 1;
1115                 call->curpos =
1116                     (char *) call->currentPacket->wirevec[1].iov_base +
1117                     call->conn->securityHeaderSize;
1118                 call->curlen =
1119                     call->currentPacket->wirevec[1].iov_len -
1120                     call->conn->securityHeaderSize;
1121             }
1122         }
1123
1124         if (nbytes) {
1125             /* The next iovec should point to the current position */
1126             if (iov[nextio].iov_base != call->curpos
1127                 || iov[nextio].iov_len > (int)call->curlen) {
1128                 call->error = RX_PROTOCOL_ERROR;
1129                 MUTEX_EXIT(&call->lock);
1130                 if (call->currentPacket) {
1131 #ifdef RX_TRACK_PACKETS
1132                     call->currentPacket->flags &= ~RX_PKTFLAG_CP;
1133 #endif
1134                     opr_queue_Prepend(&tmpq, &call->currentPacket->entry);
1135 #ifdef RXDEBUG_PACKET
1136                     tmpqc++;
1137 #endif /* RXDEBUG_PACKET */
1138                     call->currentPacket = NULL;
1139                 }
1140 #ifdef RXDEBUG_PACKET
1141                 tmpqc -=
1142 #endif /* RXDEBUG_PACKET */
1143                     rxi_FreePackets(0, &tmpq);
1144                 return 0;
1145             }
1146             nbytes -= iov[nextio].iov_len;
1147             call->curpos += iov[nextio].iov_len;
1148             call->curlen -= iov[nextio].iov_len;
1149             call->nFree -= iov[nextio].iov_len;
1150             nextio++;
1151             if (call->curlen == 0) {
1152                 if (++call->curvec > call->currentPacket->niovecs) {
1153                     call->nFree = 0;
1154                 } else {
1155                     call->curpos =
1156                         call->currentPacket->wirevec[call->curvec].iov_base;
1157                     call->curlen =
1158                         call->currentPacket->wirevec[call->curvec].iov_len;
1159                 }
1160             }
1161         }
1162     } while (nbytes && nextio < nio);
1163
1164     /* Move the packets from the temporary queue onto the transmit queue.
1165      * We may end up with more than call->twind packets on the queue. */
1166
1167 #ifdef RX_TRACK_PACKETS
1168     for (opr_queue_Scan(&tmpq, cursor))
1169     {
1170         struct rx_packet *p = opr_queue_Entry(cursor, struct rx_packet, entry);
1171         p->flags |= RX_PKTFLAG_TQ;
1172     }
1173 #endif
1174     if (call->error)
1175         call->mode = RX_MODE_ERROR;
1176
1177     opr_queue_SpliceAppend(&call->tq, &tmpq);
1178
1179     /* If the call is in recovery, let it exhaust its current retransmit
1180      * queue before forcing it to send new packets
1181      */
1182     if (!(call->flags & RX_CALL_FAST_RECOVER)) {
1183         rxi_Start(call, 0);
1184     }
1185
1186     /* Wait for the length of the transmit queue to fall below call->twind */
1187     while (!call->error && call->tnext + 1 > call->tfirst + (2 * call->twind)) {
1188         clock_NewTime();
1189         call->startWait = clock_Sec();
1190 #ifdef  RX_ENABLE_LOCKS
1191         CV_WAIT(&call->cv_twind, &call->lock);
1192 #else
1193         call->flags |= RX_CALL_WAIT_WINDOW_ALLOC;
1194         osi_rxSleep(&call->twind);
1195 #endif
1196         call->startWait = 0;
1197     }
1198
1199     if (call->error) {
1200         call->mode = RX_MODE_ERROR;
1201         call->currentPacket = NULL;
1202         MUTEX_EXIT(&call->lock);
1203         if (call->currentPacket) {
1204 #ifdef RX_TRACK_PACKETS
1205             call->currentPacket->flags &= ~RX_PKTFLAG_CP;
1206 #endif
1207             rxi_FreePacket(call->currentPacket);
1208         }
1209         return 0;
1210     }
1211     MUTEX_EXIT(&call->lock);
1212
1213     return requestCount - nbytes;
1214 }
1215
1216 int
1217 rx_WritevProc(struct rx_call *call, struct iovec *iov, int nio, int nbytes)
1218 {
1219     int bytes;
1220     SPLVAR;
1221
1222     NETPRI;
1223     bytes = rxi_WritevProc(call, iov, nio, nbytes);
1224     USERPRI;
1225     return bytes;
1226 }
1227
1228 /* Flush any buffered data to the stream, switch to read mode
1229  * (clients) or to EOF mode (servers)
1230  *
1231  * LOCKS HELD: called at netpri.
1232  */
1233 void
1234 rxi_FlushWrite(struct rx_call *call)
1235 {
1236     struct rx_packet *cp = NULL;
1237
1238     /* Free any packets from the last call to ReadvProc/WritevProc */
1239     if (!opr_queue_IsEmpty(&call->iovq)) {
1240 #ifdef RXDEBUG_PACKET
1241         call->iovqc -=
1242 #endif /* RXDEBUG_PACKET */
1243             rxi_FreePackets(0, &call->iovq);
1244     }
1245
1246     if (call->mode == RX_MODE_SENDING) {
1247
1248         call->mode =
1249             (call->conn->type ==
1250              RX_CLIENT_CONNECTION ? RX_MODE_RECEIVING : RX_MODE_EOF);
1251
1252 #ifdef RX_KERNEL_TRACE
1253         {
1254             int glockOwner = ISAFS_GLOCK();
1255             if (!glockOwner)
1256                 AFS_GLOCK();
1257             afs_Trace3(afs_iclSetp, CM_TRACE_WASHERE, ICL_TYPE_STRING,
1258                        __FILE__, ICL_TYPE_INT32, __LINE__, ICL_TYPE_POINTER,
1259                        call);
1260             if (!glockOwner)
1261                 AFS_GUNLOCK();
1262         }
1263 #endif
1264
1265         MUTEX_ENTER(&call->lock);
1266         if (call->error)
1267             call->mode = RX_MODE_ERROR;
1268
1269         cp = call->currentPacket;
1270
1271         if (cp) {
1272             /* cp->length is only supposed to be the user's data */
1273             /* cp->length was already set to (then-current)
1274              * MaxUserDataSize or less. */
1275 #ifdef RX_TRACK_PACKETS
1276             cp->flags &= ~RX_PKTFLAG_CP;
1277 #endif
1278             cp->length -= call->nFree;
1279             call->currentPacket = (struct rx_packet *)0;
1280             call->nFree = 0;
1281         } else {
1282             cp = rxi_AllocSendPacket(call, 0);
1283             if (!cp) {
1284                 /* Mode can no longer be MODE_SENDING */
1285                 return;
1286             }
1287             cp->length = 0;
1288             cp->niovecs = 2;    /* header + space for rxkad stuff */
1289             call->nFree = 0;
1290         }
1291
1292         /* The 1 specifies that this is the last packet */
1293         call->bytesSent += cp->length;
1294         rxi_PrepareSendPacket(call, cp, 1);
1295 #ifdef  AFS_GLOBAL_RXLOCK_KERNEL
1296         /* PrepareSendPacket drops the call lock */
1297         rxi_WaitforTQBusy(call);
1298 #endif /* AFS_GLOBAL_RXLOCK_KERNEL */
1299 #ifdef RX_TRACK_PACKETS
1300         cp->flags |= RX_PKTFLAG_TQ;
1301 #endif
1302         opr_queue_Append(&call->tq, &cp->entry);
1303 #ifdef RXDEBUG_PACKET
1304         call->tqc++;
1305 #endif /* RXDEBUG_PACKET */
1306
1307         /* If the call is in recovery, let it exhaust its current retransmit
1308          * queue before forcing it to send new packets
1309          */
1310         if (!(call->flags & RX_CALL_FAST_RECOVER)) {
1311             rxi_Start(call, 0);
1312         }
1313         MUTEX_EXIT(&call->lock);
1314     }
1315 }
1316
1317 /* Flush any buffered data to the stream, switch to read mode
1318  * (clients) or to EOF mode (servers) */
1319 void
1320 rx_FlushWrite(struct rx_call *call)
1321 {
1322     SPLVAR;
1323     NETPRI;
1324     rxi_FlushWrite(call);
1325     USERPRI;
1326 }