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 #endif /* KERNEL */
  57
  58 #include "rx.h"
  59 #include "rx_clock.h"
  60 #include "rx_queue.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 /* rxi_ReadProc -- internal version.
  73  *
  74  * LOCKS USED -- called at netpri
  75  */
  76 int
  77 rxi_ReadProc(struct rx_call *call, char *buf,
  78              int nbytes)
  79 {
  80     struct rx_packet *rp;
  81     int requestCount;
  82     unsigned int t;
  83
  84 /* XXXX took out clock_NewTime from here.  Was it needed? */
  85     requestCount = nbytes;
  86
  87     /* Free any packets from the last call to ReadvProc/WritevProc */
  88     if (queue_IsNotEmpty(&call->iovq)) {
  89 #ifdef RXDEBUG_PACKET
  90         call->iovqc -=
  91 #endif /* RXDEBUG_PACKET */
  92             rxi_FreePackets(0, &call->iovq);
  93     }
  94
  95     do {
  96         if (call->nLeft == 0) {
  97             /* Get next packet */
  98             MUTEX_ENTER(&call->lock);
  99             for (;;) {
 100                 if (call->error || (call->mode != RX_MODE_RECEIVING)) {
 101                     if (call->error) {
 102                         call->mode = RX_MODE_ERROR;
 103                         MUTEX_EXIT(&call->lock);
 104                         return 0;
 105                     }
 106                     if (call->mode == RX_MODE_SENDING) {
 107                         MUTEX_EXIT(&call->lock);
 108                         rxi_FlushWrite(call);
 109                         MUTEX_ENTER(&call->lock);
 110                         continue;
 111                     }
 112                 }
 113                 if (queue_IsNotEmpty(&call->rq)) {
 114                     /* Check that next packet available is next in sequence */
 115                     rp = queue_First(&call->rq, rx_packet);
 116                     if (rp->header.seq == call->rnext) {
 117                         afs_int32 error;
 118                         struct rx_connection *conn = call->conn;
 119                         queue_Remove(rp);
 120 #ifdef RX_TRACK_PACKETS
 121                         rp->flags &= ~RX_PKTFLAG_RQ;
 122 #endif
 123 #ifdef RXDEBUG_PACKET
 124                         call->rqc--;
 125 #endif /* RXDEBUG_PACKET */
 126
 127                         /* RXS_CheckPacket called to undo RXS_PreparePacket's
 128                          * work.  It may reduce the length of the packet by up
 129                          * to conn->maxTrailerSize, to reflect the length of the
 130                          * data + the header. */
 131                         if ((error =
 132                              RXS_CheckPacket(conn->securityObject, call,
 133                                              rp))) {
 134                             /* Used to merely shut down the call, but now we
 135                              * shut down the whole connection since this may
 136                              * indicate an attempt to hijack it */
 137
 138                             MUTEX_EXIT(&call->lock);
 139                             rxi_ConnectionError(conn, error);
 140                             MUTEX_ENTER(&conn->conn_data_lock);
 141                             rp = rxi_SendConnectionAbort(conn, rp, 0, 0);
 142                             MUTEX_EXIT(&conn->conn_data_lock);
 143                             rxi_FreePacket(rp);
 144
 145                             return 0;
 146                         }
 147                         call->rnext++;
 148                         call->currentPacket = rp;
 149 #ifdef RX_TRACK_PACKETS
 150                         call->currentPacket->flags |= RX_PKTFLAG_CP;
 151 #endif
 152                         call->curvec = 1;       /* 0th vec is always header */
 153                         /* begin at the beginning [ more or less ], continue
 154                          * on until the end, then stop. */
 155                         call->curpos =
 156                             (char *) call->currentPacket->wirevec[1].iov_base +
 157                             call->conn->securityHeaderSize;
 158                         call->curlen =
 159                             call->currentPacket->wirevec[1].iov_len -
 160                             call->conn->securityHeaderSize;
 161
 162                         /* Notice that this code works correctly if the data
 163                          * size is 0 (which it may be--no reply arguments from
 164                          * server, for example).  This relies heavily on the
 165                          * fact that the code below immediately frees the packet
 166                          * (no yields, etc.).  If it didn't, this would be a
 167                          * problem because a value of zero for call->nLeft
 168                          * normally means that there is no read packet */
 169                         call->nLeft = call->currentPacket->length;
 170                         hadd32(call->bytesRcvd, call->currentPacket->length);
 171
 172                         /* Send a hard ack for every rxi_HardAckRate+1 packets
 173                          * consumed. Otherwise schedule an event to send
 174                          * the hard ack later on.
 175                          */
 176                         call->nHardAcks++;
 177                         if (!(call->flags & RX_CALL_RECEIVE_DONE)) {
 178                             if (call->nHardAcks > (u_short) rxi_HardAckRate) {
 179                                 rxevent_Cancel(&call->delayedAckEvent, call,
 180                                                RX_CALL_REFCOUNT_DELAY);
 181                                 rxi_SendAck(call, 0, 0, RX_ACK_DELAY, 0);
 182                             } else {
 183                                 /* Delay to consolidate ack packets */
 184                                 rxi_PostDelayedAckEvent(call,
 185                                                         &rx_hardAckDelay);
 186                             }
 187                         }
 188                         break;
 189                     }
 190                 }
 191
 192                 /*
 193                  * If we reach this point either we have no packets in the
 194                  * receive queue or the next packet in the queue is not the
 195                  * one we are looking for.  There is nothing else for us to
 196                  * do but wait for another packet to arrive.
 197                  */
 198
 199                 /* Are there ever going to be any more packets? */
 200                 if (call->flags & RX_CALL_RECEIVE_DONE) {
 201                     MUTEX_EXIT(&call->lock);
 202                     return requestCount - nbytes;
 203                 }
 204                 /* Wait for in-sequence packet */
 205                 call->flags |= RX_CALL_READER_WAIT;
 206                 clock_NewTime();
 207                 call->startWait = clock_Sec();
 208                 while (call->flags & RX_CALL_READER_WAIT) {
 209 #ifdef  RX_ENABLE_LOCKS
 210                     CV_WAIT(&call->cv_rq, &call->lock);
 211 #else
 212                     osi_rxSleep(&call->rq);
 213 #endif
 214                 }
 215
 216                 call->startWait = 0;
 217 #ifdef RX_ENABLE_LOCKS
 218                 if (call->error) {
 219                     MUTEX_EXIT(&call->lock);
 220                     return 0;
 221                 }
 222 #endif /* RX_ENABLE_LOCKS */
 223             }
 224             MUTEX_EXIT(&call->lock);
 225         } else
 226             /* osi_Assert(cp); */
 227             /* MTUXXX  this should be replaced by some error-recovery code before shipping */
 228             /* yes, the following block is allowed to be the ELSE clause (or not) */
 229             /* It's possible for call->nLeft to be smaller than any particular
 230              * iov_len.  Usually, recvmsg doesn't change the iov_len, since it
 231              * reflects the size of the buffer.  We have to keep track of the
 232              * number of bytes read in the length field of the packet struct.  On
 233              * the final portion of a received packet, it's almost certain that
 234              * call->nLeft will be smaller than the final buffer. */
 235             while (nbytes && call->currentPacket) {
 236                 t = MIN((int)call->curlen, nbytes);
 237                 t = MIN(t, (int)call->nLeft);
 238                 memcpy(buf, call->curpos, t);
 239                 buf += t;
 240                 nbytes -= t;
 241                 call->curpos += t;
 242                 call->curlen -= t;
 243                 call->nLeft -= t;
 244
 245                 if (!call->nLeft) {
 246                     /* out of packet.  Get another one. */
 247 #ifdef RX_TRACK_PACKETS
 248                     call->currentPacket->flags &= ~RX_PKTFLAG_CP;
 249 #endif
 250                     rxi_FreePacket(call->currentPacket);
 251                     call->currentPacket = NULL;
 252                 } else if (!call->curlen) {
 253                     /* need to get another struct iov */
 254                     if (++call->curvec >= call->currentPacket->niovecs) {
 255                         /* current packet is exhausted, get ready for another */
 256                         /* don't worry about curvec and stuff, they get set somewhere else */
 257 #ifdef RX_TRACK_PACKETS
 258                         call->currentPacket->flags &= ~RX_PKTFLAG_CP;
 259 #endif
 260                         rxi_FreePacket(call->currentPacket);
 261                         call->currentPacket = NULL;
 262                         call->nLeft = 0;
 263                     } else {
 264                         call->curpos =
 265                             call->currentPacket->wirevec[call->curvec].iov_base;
 266                         call->curlen =
 267                             call->currentPacket->wirevec[call->curvec].iov_len;
 268                     }
 269                 }
 270             }
 271         if (!nbytes) {
 272             /* user buffer is full, return */
 273             return requestCount;
 274         }
 275
 276     } while (nbytes);
 277
 278     return requestCount;
 279 }
 280
 281 int
 282 rx_ReadProc(struct rx_call *call, char *buf, int nbytes)
 283 {
 284     int bytes;
 285     SPLVAR;
 286
 287     /* Free any packets from the last call to ReadvProc/WritevProc */
 288     if (!queue_IsEmpty(&call->iovq)) {
 289 #ifdef RXDEBUG_PACKET
 290         call->iovqc -=
 291 #endif /* RXDEBUG_PACKET */
 292             rxi_FreePackets(0, &call->iovq);
 293     }
 294
 295     /*
 296      * Most common case, all of the data is in the current iovec.
 297      * We are relying on nLeft being zero unless the call is in receive mode.
 298      */
 299     if (!call->error && call->curlen > nbytes && call->nLeft > nbytes) {
 300         memcpy(buf, call->curpos, nbytes);
 301
 302         call->curpos += nbytes;
 303         call->curlen -= nbytes;
 304         call->nLeft  -= nbytes;
 305
 306         if (!call->nLeft && call->currentPacket != NULL) {
 307             /* out of packet.  Get another one. */
 308             rxi_FreePacket(call->currentPacket);
 309             call->currentPacket = (struct rx_packet *)0;
 310         }
 311         return nbytes;
 312     }
 313
 314     NETPRI;
 315     bytes = rxi_ReadProc(call, buf, nbytes);
 316     USERPRI;
 317     return bytes;
 318 }
 319
 320 /* Optimization for unmarshalling 32 bit integers */
 321 int
 322 rx_ReadProc32(struct rx_call *call, afs_int32 * value)
 323 {
 324     int bytes;
 325     SPLVAR;
 326
 327     /* Free any packets from the last call to ReadvProc/WritevProc */
 328     if (!queue_IsEmpty(&call->iovq)) {
 329 #ifdef RXDEBUG_PACKET
 330         call->iovqc -=
 331 #endif /* RXDEBUG_PACKET */
 332             rxi_FreePackets(0, &call->iovq);
 333     }
 334
 335     /*
 336      * Most common case, all of the data is in the current iovec.
 337      * We are relying on nLeft being zero unless the call is in receive mode.
 338      */
 339     if (!call->error && call->curlen >= sizeof(afs_int32)
 340         && call->nLeft >= sizeof(afs_int32)) {
 341
 342         memcpy((char *)value, call->curpos, sizeof(afs_int32));
 343
 344         call->curpos += sizeof(afs_int32);
 345         call->curlen -= sizeof(afs_int32);
 346         call->nLeft  -= sizeof(afs_int32);
 347
 348         if (!call->nLeft && call->currentPacket != NULL) {
 349             /* out of packet.  Get another one. */
 350             rxi_FreePacket(call->currentPacket);
 351             call->currentPacket = (struct rx_packet *)0;
 352         }
 353         return sizeof(afs_int32);
 354     }
 355
 356     NETPRI;
 357     bytes = rxi_ReadProc(call, (char *)value, sizeof(afs_int32));
 358     USERPRI;
 359
 360     return bytes;
 361 }
 362
 363 /* rxi_FillReadVec
 364  *
 365  * Uses packets in the receive queue to fill in as much of the
 366  * current iovec as possible. Does not block if it runs out
 367  * of packets to complete the iovec. Return true if an ack packet
 368  * was sent, otherwise return false */
 369 int
 370 rxi_FillReadVec(struct rx_call *call, afs_uint32 serial)
 371 {
 372     int didConsume = 0;
 373     int didHardAck = 0;
 374     unsigned int t;
 375     struct rx_packet *rp;
 376     struct iovec *call_iov;
 377     struct iovec *cur_iov = NULL;
 378
 379     if (call->currentPacket) {
 380         cur_iov = &call->currentPacket->wirevec[call->curvec];
 381     }
 382     call_iov = &call->iov[call->iovNext];
 383
 384     while (!call->error && call->iovNBytes && call->iovNext < call->iovMax) {
 385         if (call->nLeft == 0) {
 386             /* Get next packet */
 387             if (queue_IsNotEmpty(&call->rq)) {
 388                 /* Check that next packet available is next in sequence */
 389                 rp = queue_First(&call->rq, rx_packet);
 390                 if (rp->header.seq == call->rnext) {
 391                     afs_int32 error;
 392                     struct rx_connection *conn = call->conn;
 393                     queue_Remove(rp);
 394 #ifdef RX_TRACK_PACKETS
 395                     rp->flags &= ~RX_PKTFLAG_RQ;
 396 #endif
 397 #ifdef RXDEBUG_PACKET
 398                     call->rqc--;
 399 #endif /* RXDEBUG_PACKET */
 400
 401                     /* RXS_CheckPacket called to undo RXS_PreparePacket's
 402                      * work.  It may reduce the length of the packet by up
 403                      * to conn->maxTrailerSize, to reflect the length of the
 404                      * data + the header. */
 405                     if ((error =
 406                          RXS_CheckPacket(conn->securityObject, call, rp))) {
 407                         /* Used to merely shut down the call, but now we
 408                          * shut down the whole connection since this may
 409                          * indicate an attempt to hijack it */
 410
 411                         MUTEX_EXIT(&call->lock);
 412                         rxi_ConnectionError(conn, error);
 413                         MUTEX_ENTER(&conn->conn_data_lock);
 414                         rp = rxi_SendConnectionAbort(conn, rp, 0, 0);
 415                         MUTEX_EXIT(&conn->conn_data_lock);
 416                         rxi_FreePacket(rp);
 417                         MUTEX_ENTER(&call->lock);
 418
 419                         return 1;
 420                     }
 421                     call->rnext++;
 422                     call->currentPacket = rp;
 423 #ifdef RX_TRACK_PACKETS
 424                     call->currentPacket->flags |= RX_PKTFLAG_CP;
 425 #endif
 426                     call->curvec = 1;   /* 0th vec is always header */
 427                     cur_iov = &call->currentPacket->wirevec[1];
 428                     /* begin at the beginning [ more or less ], continue
 429                      * on until the end, then stop. */
 430                     call->curpos =
 431                         (char *)call->currentPacket->wirevec[1].iov_base +
 432                         call->conn->securityHeaderSize;
 433                     call->curlen =
 434                         call->currentPacket->wirevec[1].iov_len -
 435                         call->conn->securityHeaderSize;
 436
 437                     /* Notice that this code works correctly if the data
 438                      * size is 0 (which it may be--no reply arguments from
 439                      * server, for example).  This relies heavily on the
 440                      * fact that the code below immediately frees the packet
 441                      * (no yields, etc.).  If it didn't, this would be a
 442                      * problem because a value of zero for call->nLeft
 443                      * normally means that there is no read packet */
 444                     call->nLeft = call->currentPacket->length;
 445                     hadd32(call->bytesRcvd, call->currentPacket->length);
 446
 447                     /* Send a hard ack for every rxi_HardAckRate+1 packets
 448                      * consumed. Otherwise schedule an event to send
 449                      * the hard ack later on.
 450                      */
 451                     call->nHardAcks++;
 452                     didConsume = 1;
 453                     continue;
 454                 }
 455             }
 456             break;
 457         }
 458
 459         /* It's possible for call->nLeft to be smaller than any particular
 460          * iov_len.  Usually, recvmsg doesn't change the iov_len, since it
 461          * reflects the size of the buffer.  We have to keep track of the
 462          * number of bytes read in the length field of the packet struct.  On
 463          * the final portion of a received packet, it's almost certain that
 464          * call->nLeft will be smaller than the final buffer. */
 465         while (call->iovNBytes
 466                && call->iovNext < call->iovMax
 467                && call->currentPacket) {
 468
 469             t = MIN((int)call->curlen, call->iovNBytes);
 470             t = MIN(t, (int)call->nLeft);
 471             call_iov->iov_base = call->curpos;
 472             call_iov->iov_len = t;
 473             call_iov++;
 474             call->iovNext++;
 475             call->iovNBytes -= t;
 476             call->curpos += t;
 477             call->curlen -= t;
 478             call->nLeft -= t;
 479
 480             if (!call->nLeft) {
 481                 /* out of packet.  Get another one. */
 482 #ifdef RX_TRACK_PACKETS
 483                 call->currentPacket->flags &= ~RX_PKTFLAG_CP;
 484                 call->currentPacket->flags |= RX_PKTFLAG_IOVQ;
 485 #endif
 486                 queue_Append(&call->iovq, call->currentPacket);
 487 #ifdef RXDEBUG_PACKET
 488                 call->iovqc++;
 489 #endif /* RXDEBUG_PACKET */
 490                 call->currentPacket = NULL;
 491             } else if (!call->curlen) {
 492                 /* need to get another struct iov */
 493                 if (++call->curvec >= call->currentPacket->niovecs) {
 494                     /* current packet is exhausted, get ready for another */
 495                     /* don't worry about curvec and stuff, they get set somewhere else */
 496 #ifdef RX_TRACK_PACKETS
 497                     call->currentPacket->flags &= ~RX_PKTFLAG_CP;
 498                     call->currentPacket->flags |= RX_PKTFLAG_IOVQ;
 499 #endif
 500                     queue_Append(&call->iovq, call->currentPacket);
 501 #ifdef RXDEBUG_PACKET
 502                     call->iovqc++;
 503 #endif /* RXDEBUG_PACKET */
 504                     call->currentPacket = NULL;
 505                     call->nLeft = 0;
 506                 } else {
 507                     cur_iov++;
 508                     call->curpos = (char *)cur_iov->iov_base;
 509                     call->curlen = cur_iov->iov_len;
 510                 }
 511             }
 512         }
 513     }
 514
 515     /* If we consumed any packets then check whether we need to
 516      * send a hard ack. */
 517     if (didConsume && (!(call->flags & RX_CALL_RECEIVE_DONE))) {
 518         if (call->nHardAcks > (u_short) rxi_HardAckRate) {
 519             rxevent_Cancel(&call->delayedAckEvent, call,
 520                            RX_CALL_REFCOUNT_DELAY);
 521             rxi_SendAck(call, 0, serial, RX_ACK_DELAY, 0);
 522             didHardAck = 1;
 523         } else {
 524             /* Delay to consolidate ack packets */
 525             rxi_PostDelayedAckEvent(call, &rx_hardAckDelay);
 526         }
 527     }
 528     return didHardAck;
 529 }
 530
 531
 532 /* rxi_ReadvProc -- internal version.
 533  *
 534  * Fills in an iovec with pointers to the packet buffers. All packets
 535  * except the last packet (new current packet) are moved to the iovq
 536  * while the application is processing the data.
 537  *
 538  * LOCKS USED -- called at netpri.
 539  */
 540 int
 541 rxi_ReadvProc(struct rx_call *call, struct iovec *iov, int *nio, int maxio,
 542               int nbytes)
 543 {
 544     int bytes;
 545
 546     /* Free any packets from the last call to ReadvProc/WritevProc */
 547     if (queue_IsNotEmpty(&call->iovq)) {
 548 #ifdef RXDEBUG_PACKET
 549         call->iovqc -=
 550 #endif /* RXDEBUG_PACKET */
 551             rxi_FreePackets(0, &call->iovq);
 552     }
 553
 554     if (call->mode == RX_MODE_SENDING) {
 555         rxi_FlushWrite(call);
 556     }
 557
 558     MUTEX_ENTER(&call->lock);
 559     if (call->error)
 560         goto error;
 561
 562     /* Get whatever data is currently available in the receive queue.
 563      * If rxi_FillReadVec sends an ack packet then it is possible
 564      * that we will receive more data while we drop the call lock
 565      * to send the packet. Set the RX_CALL_IOVEC_WAIT flag
 566      * here to avoid a race with the receive thread if we send
 567      * hard acks in rxi_FillReadVec. */
 568     call->flags |= RX_CALL_IOVEC_WAIT;
 569     call->iovNBytes = nbytes;
 570     call->iovMax = maxio;
 571     call->iovNext = 0;
 572     call->iov = iov;
 573     rxi_FillReadVec(call, 0);
 574
 575     /* if we need more data then sleep until the receive thread has
 576      * filled in the rest. */
 577     if (!call->error && call->iovNBytes && call->iovNext < call->iovMax
 578         && !(call->flags & RX_CALL_RECEIVE_DONE)) {
 579         call->flags |= RX_CALL_READER_WAIT;
 580         clock_NewTime();
 581         call->startWait = clock_Sec();
 582         while (call->flags & RX_CALL_READER_WAIT) {
 583 #ifdef  RX_ENABLE_LOCKS
 584             CV_WAIT(&call->cv_rq, &call->lock);
 585 #else
 586             osi_rxSleep(&call->rq);
 587 #endif
 588         }
 589         call->startWait = 0;
 590     }
 591     call->flags &= ~RX_CALL_IOVEC_WAIT;
 592
 593     if (call->error)
 594         goto error;
 595
 596     call->iov = NULL;
 597     *nio = call->iovNext;
 598     bytes = nbytes - call->iovNBytes;
 599     MUTEX_EXIT(&call->lock);
 600     return bytes;
 601
 602   error:
 603     MUTEX_EXIT(&call->lock);
 604     call->mode = RX_MODE_ERROR;
 605     return 0;
 606 }
 607
 608 int
 609 rx_ReadvProc(struct rx_call *call, struct iovec *iov, int *nio, int maxio,
 610              int nbytes)
 611 {
 612     int bytes;
 613     SPLVAR;
 614
 615     NETPRI;
 616     bytes = rxi_ReadvProc(call, iov, nio, maxio, nbytes);
 617     USERPRI;
 618     return bytes;
 619 }
 620
 621 /* rxi_WriteProc -- internal version.
 622  *
 623  * LOCKS USED -- called at netpri
 624  */
 625
 626 int
 627 rxi_WriteProc(struct rx_call *call, char *buf,
 628               int nbytes)
 629 {
 630     struct rx_connection *conn = call->conn;
 631     unsigned int t;
 632     int requestCount = nbytes;
 633
 634     /* Free any packets from the last call to ReadvProc/WritevProc */
 635     if (queue_IsNotEmpty(&call->iovq)) {
 636 #ifdef RXDEBUG_PACKET
 637         call->iovqc -=
 638 #endif /* RXDEBUG_PACKET */
 639             rxi_FreePackets(0, &call->iovq);
 640     }
 641
 642     if (call->mode != RX_MODE_SENDING) {
 643         if ((conn->type == RX_SERVER_CONNECTION)
 644             && (call->mode == RX_MODE_RECEIVING)) {
 645             call->mode = RX_MODE_SENDING;
 646             if (call->currentPacket) {
 647 #ifdef RX_TRACK_PACKETS
 648                 call->currentPacket->flags &= ~RX_PKTFLAG_CP;
 649 #endif
 650                 rxi_FreePacket(call->currentPacket);
 651                 call->currentPacket = NULL;
 652                 call->nLeft = 0;
 653                 call->nFree = 0;
 654             }
 655         } else {
 656             return 0;
 657         }
 658     }
 659
 660     /* Loop condition is checked at end, so that a write of 0 bytes
 661      * will force a packet to be created--specially for the case where
 662      * there are 0 bytes on the stream, but we must send a packet
 663      * anyway. */
 664     do {
 665         if (call->nFree == 0) {
 666             MUTEX_ENTER(&call->lock);
 667             if (call->error)
 668                 call->mode = RX_MODE_ERROR;
 669             if (!call->error && call->currentPacket) {
 670                 clock_NewTime();        /* Bogus:  need new time package */
 671                 /* The 0, below, specifies that it is not the last packet:
 672                  * there will be others. PrepareSendPacket may
 673                  * alter the packet length by up to
 674                  * conn->securityMaxTrailerSize */
 675                 hadd32(call->bytesSent, call->currentPacket->length);
 676                 rxi_PrepareSendPacket(call, call->currentPacket, 0);
 677 #ifdef  AFS_GLOBAL_RXLOCK_KERNEL
 678                 /* PrepareSendPacket drops the call lock */
 679                 rxi_WaitforTQBusy(call);
 680 #endif /* AFS_GLOBAL_RXLOCK_KERNEL */
 681 #ifdef RX_TRACK_PACKETS
 682                 call->currentPacket->flags |= RX_PKTFLAG_TQ;
 683 #endif
 684                 queue_Append(&call->tq, call->currentPacket);
 685 #ifdef RXDEBUG_PACKET
 686                 call->tqc++;
 687 #endif /* RXDEBUG_PACKET */
 688 #ifdef RX_TRACK_PACKETS
 689                 call->currentPacket->flags &= ~RX_PKTFLAG_CP;
 690 #endif
 691                 call->currentPacket = NULL;
 692
 693                 /* If the call is in recovery, let it exhaust its current
 694                  * retransmit queue before forcing it to send new packets
 695                  */
 696                 if (!(call->flags & (RX_CALL_FAST_RECOVER))) {
 697                     rxi_Start(call, 0);
 698                 }
 699             } else if (call->currentPacket) {
 700 #ifdef RX_TRACK_PACKETS
 701                 call->currentPacket->flags &= ~RX_PKTFLAG_CP;
 702 #endif
 703                 rxi_FreePacket(call->currentPacket);
 704                 call->currentPacket = NULL;
 705             }
 706             /* Wait for transmit window to open up */
 707             while (!call->error
 708                    && call->tnext + 1 > call->tfirst + (2 * call->twind)) {
 709                 clock_NewTime();
 710                 call->startWait = clock_Sec();
 711
 712 #ifdef  RX_ENABLE_LOCKS
 713                 CV_WAIT(&call->cv_twind, &call->lock);
 714 #else
 715                 call->flags |= RX_CALL_WAIT_WINDOW_ALLOC;
 716                 osi_rxSleep(&call->twind);
 717 #endif
 718
 719                 call->startWait = 0;
 720 #ifdef RX_ENABLE_LOCKS
 721                 if (call->error) {
 722                     call->mode = RX_MODE_ERROR;
 723                     MUTEX_EXIT(&call->lock);
 724                     return 0;
 725                 }
 726 #endif /* RX_ENABLE_LOCKS */
 727             }
 728             if ((call->currentPacket = rxi_AllocSendPacket(call, nbytes))) {
 729 #ifdef RX_TRACK_PACKETS
 730                 call->currentPacket->flags |= RX_PKTFLAG_CP;
 731 #endif
 732                 call->nFree = call->currentPacket->length;
 733                 call->curvec = 1;       /* 0th vec is always header */
 734                 /* begin at the beginning [ more or less ], continue
 735                  * on until the end, then stop. */
 736                 call->curpos =
 737                     (char *) call->currentPacket->wirevec[1].iov_base +
 738                     call->conn->securityHeaderSize;
 739                 call->curlen =
 740                     call->currentPacket->wirevec[1].iov_len -
 741                     call->conn->securityHeaderSize;
 742             }
 743             if (call->error) {
 744                 call->mode = RX_MODE_ERROR;
 745                 if (call->currentPacket) {
 746 #ifdef RX_TRACK_PACKETS
 747                     call->currentPacket->flags &= ~RX_PKTFLAG_CP;
 748 #endif
 749                     rxi_FreePacket(call->currentPacket);
 750                     call->currentPacket = NULL;
 751                 }
 752                 MUTEX_EXIT(&call->lock);
 753                 return 0;
 754             }
 755             MUTEX_EXIT(&call->lock);
 756         }
 757
 758         if (call->currentPacket && (int)call->nFree < nbytes) {
 759             /* Try to extend the current buffer */
 760             int len, mud;
 761             len = call->currentPacket->length;
 762             mud = rx_MaxUserDataSize(call);
 763             if (mud > len) {
 764                 int want;
 765                 want = MIN(nbytes - (int)call->nFree, mud - len);
 766                 rxi_AllocDataBuf(call->currentPacket, want,
 767                                  RX_PACKET_CLASS_SEND_CBUF);
 768                 if (call->currentPacket->length > (unsigned)mud)
 769                     call->currentPacket->length = mud;
 770                 call->nFree += (call->currentPacket->length - len);
 771             }
 772         }
 773
 774         /* If the remaining bytes fit in the buffer, then store them
 775          * and return.  Don't ship a buffer that's full immediately to
 776          * the peer--we don't know if it's the last buffer yet */
 777
 778         if (!call->currentPacket) {
 779             call->nFree = 0;
 780         }
 781
 782         while (nbytes && call->nFree) {
 783
 784             t = MIN((int)call->curlen, nbytes);
 785             t = MIN((int)call->nFree, t);
 786             memcpy(call->curpos, buf, t);
 787             buf += t;
 788             nbytes -= t;
 789             call->curpos += t;
 790             call->curlen -= (u_short)t;
 791             call->nFree -= (u_short)t;
 792
 793             if (!call->curlen) {
 794                 /* need to get another struct iov */
 795                 if (++call->curvec >= call->currentPacket->niovecs) {
 796                     /* current packet is full, extend or send it */
 797                     call->nFree = 0;
 798                 } else {
 799                     call->curpos =
 800                         call->currentPacket->wirevec[call->curvec].iov_base;
 801                     call->curlen =
 802                         call->currentPacket->wirevec[call->curvec].iov_len;
 803                 }
 804             }
 805         }                       /* while bytes to send and room to send them */
 806
 807         /* might be out of space now */
 808         if (!nbytes) {
 809             return requestCount;
 810         } else;                 /* more data to send, so get another packet and keep going */
 811     } while (nbytes);
 812
 813     return requestCount - nbytes;
 814 }
 815
 816 int
 817 rx_WriteProc(struct rx_call *call, char *buf, int nbytes)
 818 {
 819     int bytes;
 820     int tcurlen;
 821     int tnFree;
 822     char *tcurpos;
 823     SPLVAR;
 824
 825     /* Free any packets from the last call to ReadvProc/WritevProc */
 826     if (queue_IsNotEmpty(&call->iovq)) {
 827 #ifdef RXDEBUG_PACKET
 828         call->iovqc -=
 829 #endif /* RXDEBUG_PACKET */
 830             rxi_FreePackets(0, &call->iovq);
 831     }
 832
 833     /*
 834      * Most common case: all of the data fits in the current iovec.
 835      * We are relying on nFree being zero unless the call is in send mode.
 836      */
 837     tcurlen = (int)call->curlen;
 838     tnFree = (int)call->nFree;
 839     if (!call->error && tcurlen >= nbytes && tnFree >= nbytes) {
 840         tcurpos = call->curpos;
 841
 842         memcpy(tcurpos, buf, nbytes);
 843         call->curpos = tcurpos + nbytes;
 844         call->curlen = (u_short)(tcurlen - nbytes);
 845         call->nFree = (u_short)(tnFree - nbytes);
 846         return nbytes;
 847     }
 848
 849     NETPRI;
 850     bytes = rxi_WriteProc(call, buf, nbytes);
 851     USERPRI;
 852     return bytes;
 853 }
 854
 855 /* Optimization for marshalling 32 bit arguments */
 856 int
 857 rx_WriteProc32(struct rx_call *call, afs_int32 * value)
 858 {
 859     int bytes;
 860     int tcurlen;
 861     int tnFree;
 862     char *tcurpos;
 863     SPLVAR;
 864
 865     if (queue_IsNotEmpty(&call->iovq)) {
 866 #ifdef RXDEBUG_PACKET
 867         call->iovqc -=
 868 #endif /* RXDEBUG_PACKET */
 869             rxi_FreePackets(0, &call->iovq);
 870     }
 871
 872     /*
 873      * Most common case: all of the data fits in the current iovec.
 874      * We are relying on nFree being zero unless the call is in send mode.
 875      */
 876     tcurlen = call->curlen;
 877     tnFree = call->nFree;
 878     if (!call->error && tcurlen >= sizeof(afs_int32)
 879         && tnFree >= sizeof(afs_int32)) {
 880         tcurpos = call->curpos;
 881
 882         if (!((size_t)tcurpos & (sizeof(afs_int32) - 1))) {
 883             *((afs_int32 *) (tcurpos)) = *value;
 884         } else {
 885             memcpy(tcurpos, (char *)value, sizeof(afs_int32));
 886         }
 887         call->curpos = tcurpos + sizeof(afs_int32);
 888         call->curlen = (u_short)(tcurlen - sizeof(afs_int32));
 889         call->nFree = (u_short)(tnFree - sizeof(afs_int32));
 890         return sizeof(afs_int32);
 891     }
 892
 893     NETPRI;
 894     bytes = rxi_WriteProc(call, (char *)value, sizeof(afs_int32));
 895     USERPRI;
 896     return bytes;
 897 }
 898
 899 /* rxi_WritevAlloc -- internal version.
 900  *
 901  * Fill in an iovec to point to data in packet buffers. The application
 902  * calls rxi_WritevProc when the buffers are full.
 903  *
 904  * LOCKS USED -- called at netpri.
 905  */
 906
 907 static int
 908 rxi_WritevAlloc(struct rx_call *call, struct iovec *iov, int *nio, int maxio,
 909                 int nbytes)
 910 {
 911     struct rx_connection *conn = call->conn;
 912     struct rx_packet *cp;
 913     int requestCount;
 914     int nextio;
 915     /* Temporary values, real work is done in rxi_WritevProc */
 916     int tnFree;
 917     unsigned int tcurvec;
 918     char *tcurpos;
 919     int tcurlen;
 920
 921     requestCount = nbytes;
 922     nextio = 0;
 923
 924     /* Free any packets from the last call to ReadvProc/WritevProc */
 925     if (queue_IsNotEmpty(&call->iovq)) {
 926 #ifdef RXDEBUG_PACKET
 927         call->iovqc -=
 928 #endif /* RXDEBUG_PACKET */
 929             rxi_FreePackets(0, &call->iovq);
 930     }
 931
 932     if (call->mode != RX_MODE_SENDING) {
 933         if ((conn->type == RX_SERVER_CONNECTION)
 934             && (call->mode == RX_MODE_RECEIVING)) {
 935             call->mode = RX_MODE_SENDING;
 936             if (call->currentPacket) {
 937 #ifdef RX_TRACK_PACKETS
 938                 call->currentPacket->flags &= ~RX_PKTFLAG_CP;
 939 #endif
 940                 rxi_FreePacket(call->currentPacket);
 941                 call->currentPacket = NULL;
 942                 call->nLeft = 0;
 943                 call->nFree = 0;
 944             }
 945         } else {
 946             return 0;
 947         }
 948     }
 949
 950     /* Set up the iovec to point to data in packet buffers. */
 951     tnFree = call->nFree;
 952     tcurvec = call->curvec;
 953     tcurpos = call->curpos;
 954     tcurlen = call->curlen;
 955     cp = call->currentPacket;
 956     do {
 957         int t;
 958
 959         if (tnFree == 0) {
 960             /* current packet is full, allocate a new one */
 961             MUTEX_ENTER(&call->lock);
 962             cp = rxi_AllocSendPacket(call, nbytes);
 963             MUTEX_EXIT(&call->lock);
 964             if (cp == NULL) {
 965                 /* out of space, return what we have */
 966                 *nio = nextio;
 967                 return requestCount - nbytes;
 968             }
 969 #ifdef RX_TRACK_PACKETS
 970             cp->flags |= RX_PKTFLAG_IOVQ;
 971 #endif
 972             queue_Append(&call->iovq, cp);
 973 #ifdef RXDEBUG_PACKET
 974             call->iovqc++;
 975 #endif /* RXDEBUG_PACKET */
 976             tnFree = cp->length;
 977             tcurvec = 1;
 978             tcurpos =
 979                 (char *)cp->wirevec[1].iov_base +
 980                 call->conn->securityHeaderSize;
 981             tcurlen = cp->wirevec[1].iov_len - call->conn->securityHeaderSize;
 982         }
 983
 984         if (tnFree < nbytes) {
 985             /* try to extend the current packet */
 986             int len, mud;
 987             len = cp->length;
 988             mud = rx_MaxUserDataSize(call);
 989             if (mud > len) {
 990                 int want;
 991                 want = MIN(nbytes - tnFree, mud - len);
 992                 rxi_AllocDataBuf(cp, want, RX_PACKET_CLASS_SEND_CBUF);
 993                 if (cp->length > (unsigned)mud)
 994                     cp->length = mud;
 995                 tnFree += (cp->length - len);
 996                 if (cp == call->currentPacket) {
 997                     call->nFree += (cp->length - len);
 998                 }
 999             }
1000         }
1001
1002         /* fill in the next entry in the iovec */
1003         t = MIN(tcurlen, nbytes);
1004         t = MIN(tnFree, t);
1005         iov[nextio].iov_base = tcurpos;
1006         iov[nextio].iov_len = t;
1007         nbytes -= t;
1008         tcurpos += t;
1009         tcurlen -= t;
1010         tnFree -= t;
1011         nextio++;
1012
1013         if (!tcurlen) {
1014             /* need to get another struct iov */
1015             if (++tcurvec >= cp->niovecs) {
1016                 /* current packet is full, extend it or move on to next packet */
1017                 tnFree = 0;
1018             } else {
1019                 tcurpos = (char *)cp->wirevec[tcurvec].iov_base;
1020                 tcurlen = cp->wirevec[tcurvec].iov_len;
1021             }
1022         }
1023     } while (nbytes && nextio < maxio);
1024     *nio = nextio;
1025     return requestCount - nbytes;
1026 }
1027
1028 int
1029 rx_WritevAlloc(struct rx_call *call, struct iovec *iov, int *nio, int maxio,
1030                int nbytes)
1031 {
1032     int bytes;
1033     SPLVAR;
1034
1035     NETPRI;
1036     bytes = rxi_WritevAlloc(call, iov, nio, maxio, nbytes);
1037     USERPRI;
1038     return bytes;
1039 }
1040
1041 /* rxi_WritevProc -- internal version.
1042  *
1043  * Send buffers allocated in rxi_WritevAlloc.
1044  *
1045  * LOCKS USED -- called at netpri.
1046  */
1047 int
1048 rxi_WritevProc(struct rx_call *call, struct iovec *iov, int nio, int nbytes)
1049 {
1050 #ifdef RX_TRACK_PACKETS
1051     struct rx_packet *p, *np;
1052 #endif
1053     int nextio;
1054     int requestCount;
1055     struct rx_queue tmpq;
1056 #ifdef RXDEBUG_PACKET
1057     u_short tmpqc;
1058 #endif
1059
1060     requestCount = nbytes;
1061     nextio = 0;
1062
1063     MUTEX_ENTER(&call->lock);
1064     if (call->error) {
1065         call->mode = RX_MODE_ERROR;
1066     } else if (call->mode != RX_MODE_SENDING) {
1067         call->error = RX_PROTOCOL_ERROR;
1068     }
1069 #ifdef AFS_GLOBAL_RXLOCK_KERNEL
1070     rxi_WaitforTQBusy(call);
1071 #endif /* AFS_GLOBAL_RXLOCK_KERNEL */
1072
1073     if (call->error) {
1074         call->mode = RX_MODE_ERROR;
1075         MUTEX_EXIT(&call->lock);
1076         if (call->currentPacket) {
1077 #ifdef RX_TRACK_PACKETS
1078             call->currentPacket->flags &= ~RX_PKTFLAG_CP;
1079             call->currentPacket->flags |= RX_PKTFLAG_IOVQ;
1080 #endif
1081             queue_Prepend(&call->iovq, call->currentPacket);
1082 #ifdef RXDEBUG_PACKET
1083             call->iovqc++;
1084 #endif /* RXDEBUG_PACKET */
1085             call->currentPacket = NULL;
1086         }
1087 #ifdef RXDEBUG_PACKET
1088         call->iovqc -=
1089 #endif /* RXDEBUG_PACKET */
1090             rxi_FreePackets(0, &call->iovq);
1091         return 0;
1092     }
1093
1094     /* Loop through the I/O vector adjusting packet pointers.
1095      * Place full packets back onto the iovq once they are ready
1096      * to send. Set RX_PROTOCOL_ERROR if any problems are found in
1097      * the iovec. We put the loop condition at the end to ensure that
1098      * a zero length write will push a short packet. */
1099     nextio = 0;
1100     queue_Init(&tmpq);
1101 #ifdef RXDEBUG_PACKET
1102     tmpqc = 0;
1103 #endif /* RXDEBUG_PACKET */
1104     do {
1105         if (call->nFree == 0 && call->currentPacket) {
1106             clock_NewTime();    /* Bogus:  need new time package */
1107             /* The 0, below, specifies that it is not the last packet:
1108              * there will be others. PrepareSendPacket may
1109              * alter the packet length by up to
1110              * conn->securityMaxTrailerSize */
1111             hadd32(call->bytesSent, call->currentPacket->length);
1112             rxi_PrepareSendPacket(call, call->currentPacket, 0);
1113 #ifdef  AFS_GLOBAL_RXLOCK_KERNEL
1114             /* PrepareSendPacket drops the call lock */
1115             rxi_WaitforTQBusy(call);
1116 #endif /* AFS_GLOBAL_RXLOCK_KERNEL */
1117             queue_Append(&tmpq, call->currentPacket);
1118 #ifdef RXDEBUG_PACKET
1119             tmpqc++;
1120 #endif /* RXDEBUG_PACKET */
1121             call->currentPacket = NULL;
1122
1123             /* The head of the iovq is now the current packet */
1124             if (nbytes) {
1125                 if (queue_IsEmpty(&call->iovq)) {
1126                     MUTEX_EXIT(&call->lock);
1127                     call->error = RX_PROTOCOL_ERROR;
1128 #ifdef RXDEBUG_PACKET
1129                     tmpqc -=
1130 #endif /* RXDEBUG_PACKET */
1131                         rxi_FreePackets(0, &tmpq);
1132                     return 0;
1133                 }
1134                 call->currentPacket = queue_First(&call->iovq, rx_packet);
1135                 queue_Remove(call->currentPacket);
1136 #ifdef RX_TRACK_PACKETS
1137                 call->currentPacket->flags &= ~RX_PKTFLAG_IOVQ;
1138                 call->currentPacket->flags |= RX_PKTFLAG_CP;
1139 #endif
1140 #ifdef RXDEBUG_PACKET
1141                 call->iovqc--;
1142 #endif /* RXDEBUG_PACKET */
1143                 call->nFree = call->currentPacket->length;
1144                 call->curvec = 1;
1145                 call->curpos =
1146                     (char *) call->currentPacket->wirevec[1].iov_base +
1147                     call->conn->securityHeaderSize;
1148                 call->curlen =
1149                     call->currentPacket->wirevec[1].iov_len -
1150                     call->conn->securityHeaderSize;
1151             }
1152         }
1153
1154         if (nbytes) {
1155             /* The next iovec should point to the current position */
1156             if (iov[nextio].iov_base != call->curpos
1157                 || iov[nextio].iov_len > (int)call->curlen) {
1158                 call->error = RX_PROTOCOL_ERROR;
1159                 MUTEX_EXIT(&call->lock);
1160                 if (call->currentPacket) {
1161 #ifdef RX_TRACK_PACKETS
1162                     call->currentPacket->flags &= ~RX_PKTFLAG_CP;
1163 #endif
1164                     queue_Prepend(&tmpq, call->currentPacket);
1165 #ifdef RXDEBUG_PACKET
1166                     tmpqc++;
1167 #endif /* RXDEBUG_PACKET */
1168                     call->currentPacket = NULL;
1169                 }
1170 #ifdef RXDEBUG_PACKET
1171                 tmpqc -=
1172 #endif /* RXDEBUG_PACKET */
1173                     rxi_FreePackets(0, &tmpq);
1174                 return 0;
1175             }
1176             nbytes -= iov[nextio].iov_len;
1177             call->curpos += iov[nextio].iov_len;
1178             call->curlen -= iov[nextio].iov_len;
1179             call->nFree -= iov[nextio].iov_len;
1180             nextio++;
1181             if (call->curlen == 0) {
1182                 if (++call->curvec > call->currentPacket->niovecs) {
1183                     call->nFree = 0;
1184                 } else {
1185                     call->curpos =
1186                         call->currentPacket->wirevec[call->curvec].iov_base;
1187                     call->curlen =
1188                         call->currentPacket->wirevec[call->curvec].iov_len;
1189                 }
1190             }
1191         }
1192     } while (nbytes && nextio < nio);
1193
1194     /* Move the packets from the temporary queue onto the transmit queue.
1195      * We may end up with more than call->twind packets on the queue. */
1196
1197 #ifdef RX_TRACK_PACKETS
1198     for (queue_Scan(&tmpq, p, np, rx_packet))
1199     {
1200         p->flags |= RX_PKTFLAG_TQ;
1201     }
1202 #endif
1203
1204     if (call->error)
1205         call->mode = RX_MODE_ERROR;
1206
1207     queue_SpliceAppend(&call->tq, &tmpq);
1208
1209     /* If the call is in recovery, let it exhaust its current retransmit
1210      * queue before forcing it to send new packets
1211      */
1212     if (!(call->flags & RX_CALL_FAST_RECOVER)) {
1213         rxi_Start(call, 0);
1214     }
1215
1216     /* Wait for the length of the transmit queue to fall below call->twind */
1217     while (!call->error && call->tnext + 1 > call->tfirst + (2 * call->twind)) {
1218         clock_NewTime();
1219         call->startWait = clock_Sec();
1220 #ifdef  RX_ENABLE_LOCKS
1221         CV_WAIT(&call->cv_twind, &call->lock);
1222 #else
1223         call->flags |= RX_CALL_WAIT_WINDOW_ALLOC;
1224         osi_rxSleep(&call->twind);
1225 #endif
1226         call->startWait = 0;
1227     }
1228
1229     if (call->error) {
1230         call->mode = RX_MODE_ERROR;
1231         call->currentPacket = NULL;
1232         MUTEX_EXIT(&call->lock);
1233         if (call->currentPacket) {
1234 #ifdef RX_TRACK_PACKETS
1235             call->currentPacket->flags &= ~RX_PKTFLAG_CP;
1236 #endif
1237             rxi_FreePacket(call->currentPacket);
1238         }
1239         return 0;
1240     }
1241     MUTEX_EXIT(&call->lock);
1242
1243     return requestCount - nbytes;
1244 }
1245
1246 int
1247 rx_WritevProc(struct rx_call *call, struct iovec *iov, int nio, int nbytes)
1248 {
1249     int bytes;
1250     SPLVAR;
1251
1252     NETPRI;
1253     bytes = rxi_WritevProc(call, iov, nio, nbytes);
1254     USERPRI;
1255     return bytes;
1256 }
1257
1258 /* Flush any buffered data to the stream, switch to read mode
1259  * (clients) or to EOF mode (servers)
1260  *
1261  * LOCKS HELD: called at netpri.
1262  */
1263 void
1264 rxi_FlushWrite(struct rx_call *call)
1265 {
1266     struct rx_packet *cp = NULL;
1267
1268     /* Free any packets from the last call to ReadvProc/WritevProc */
1269     if (queue_IsNotEmpty(&call->iovq)) {
1270 #ifdef RXDEBUG_PACKET
1271         call->iovqc -=
1272 #endif /* RXDEBUG_PACKET */
1273             rxi_FreePackets(0, &call->iovq);
1274     }
1275
1276     if (call->mode == RX_MODE_SENDING) {
1277
1278         call->mode =
1279             (call->conn->type ==
1280              RX_CLIENT_CONNECTION ? RX_MODE_RECEIVING : RX_MODE_EOF);
1281
1282 #ifdef RX_KERNEL_TRACE
1283         {
1284             int glockOwner = ISAFS_GLOCK();
1285             if (!glockOwner)
1286                 AFS_GLOCK();
1287             afs_Trace3(afs_iclSetp, CM_TRACE_WASHERE, ICL_TYPE_STRING,
1288                        __FILE__, ICL_TYPE_INT32, __LINE__, ICL_TYPE_POINTER,
1289                        call);
1290             if (!glockOwner)
1291                 AFS_GUNLOCK();
1292         }
1293 #endif
1294
1295         MUTEX_ENTER(&call->lock);
1296         if (call->error)
1297             call->mode = RX_MODE_ERROR;
1298
1299         cp = call->currentPacket;
1300
1301         if (cp) {
1302             /* cp->length is only supposed to be the user's data */
1303             /* cp->length was already set to (then-current)
1304              * MaxUserDataSize or less. */
1305 #ifdef RX_TRACK_PACKETS
1306             cp->flags &= ~RX_PKTFLAG_CP;
1307 #endif
1308             cp->length -= call->nFree;
1309             call->currentPacket = (struct rx_packet *)0;
1310             call->nFree = 0;
1311         } else {
1312             cp = rxi_AllocSendPacket(call, 0);
1313             if (!cp) {
1314                 /* Mode can no longer be MODE_SENDING */
1315                 return;
1316             }
1317             cp->length = 0;
1318             cp->niovecs = 2;    /* header + space for rxkad stuff */
1319             call->nFree = 0;
1320         }
1321
1322         /* The 1 specifies that this is the last packet */
1323         hadd32(call->bytesSent, cp->length);
1324         rxi_PrepareSendPacket(call, cp, 1);
1325 #ifdef  AFS_GLOBAL_RXLOCK_KERNEL
1326         /* PrepareSendPacket drops the call lock */
1327         rxi_WaitforTQBusy(call);
1328 #endif /* AFS_GLOBAL_RXLOCK_KERNEL */
1329 #ifdef RX_TRACK_PACKETS
1330         cp->flags |= RX_PKTFLAG_TQ;
1331 #endif
1332         queue_Append(&call->tq, cp);
1333 #ifdef RXDEBUG_PACKET
1334         call->tqc++;
1335 #endif /* RXDEBUG_PACKET */
1336
1337         /* If the call is in recovery, let it exhaust its current retransmit
1338          * queue before forcing it to send new packets
1339          */
1340         if (!(call->flags & RX_CALL_FAST_RECOVER)) {
1341             rxi_Start(call, 0);
1342         }
1343         MUTEX_EXIT(&call->lock);
1344     }
1345 }
1346
1347 /* Flush any buffered data to the stream, switch to read mode
1348  * (clients) or to EOF mode (servers) */
1349 void
1350 rx_FlushWrite(struct rx_call *call)
1351 {
1352     SPLVAR;
1353     NETPRI;
1354     rxi_FlushWrite(call);
1355     USERPRI;
1356 }