bsd/netat/adsp_Read.c

   1 /*
   2  * Copyright (c) 2000-2007 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*
  29  *
  30  * dspRead.c
  31  *
  32  * From v01.17 08/22/90 mbs
  33  *    Modified for MP, 1996 by Tuyen Nguyen
  34  *   Modified, April 9, 1997 by Tuyen Nguyen for MacOSX.
  35  */
  36
  37 #include <sys/errno.h>
  38 #include <sys/types.h>
  39 #include <sys/param.h>
  40 #include <machine/spl.h>
  41 #include <sys/systm.h>
  42 #include <sys/kernel.h>
  43 #include <sys/proc.h>
  44 #include <sys/filedesc.h>
  45 #include <sys/fcntl.h>
  46 #include <sys/mbuf.h>
  47 #include <sys/socket.h>
  48 #include <sys/socketvar.h>
  49
  50 #include <netat/sysglue.h>
  51 #include <netat/appletalk.h>
  52 #include <netat/at_pcb.h>
  53 #include <netat/debug.h>
  54 #include <netat/adsp.h>
  55 #include <netat/adsp_internal.h>
  56
  57 /*
  58  * CheckReadQueue
  59  *
  60  * Checks to see if there is any data in the receive queue.  If there
  61  * is data, a pb and the data are queued to the user.
  62  *
  63  *
  64  */
  65 extern int adsp_check;
  66
  67 int CheckReadQueue(sp)          /* (CCBPtr sp) */
  68     register CCBPtr sp;
  69 {
  70     register struct adspcmd *pb;
  71     unsigned short cnt;
  72     char eom = 0;
  73     register gbuf_t *mp;
  74     register gbuf_t *tmp;
  75     gref_t *gref;
  76
  77     dPrintf(D_M_ADSP, D_L_TRACE, ("CheckReadQueue: sp=0x%x\n", (unsigned)sp));
  78     KERNEL_DEBUG(DBG_ADSP_READ, 0, sp, sp->rbuf_mb, sp->rpb, sp->delay);
  79     trace_mbufs(D_M_ADSP_LOW, "    bCQR m", sp->rbuf_mb);
  80
  81     while (sp->rData && (pb = sp->rpb)) {               /* have data */
  82         dPrintf(D_M_ADSP, D_L_TRACE,
  83                  (" pb=0x%p, gref=0x%p, ioc=0x%p, reqCount=%d (have data)\n",
  84                   pb, pb->gref, pb->ioc, pb->u.ioParams.reqCount));
  85         KERNEL_DEBUG(DBG_ADSP_READ, 1, pb, pb->gref, pb->ioc, pb->u.ioParams.reqCount);
  86         if (pb->u.ioParams.reqCount == 0) {
  87             pb->ioResult = 0;
  88             sp->rpb = pb->qLink;
  89             if (pb->ioc) {
  90                 KERNEL_DEBUG(DBG_ADSP_READ, 2, pb, pb->gref, pb->ioc, 0);
  91                 adspioc_ack(0, (gbuf_t *)pb->ioc, pb->gref);
  92             } else {
  93                 KERNEL_DEBUG(DBG_ADSP_READ, 3, pb, pb->gref, 0, 0);
  94                 completepb(sp, pb);
  95             }
  96             continue;
  97         }
  98
  99         /* take the first packet off of sp->rbuf_mb or sp->crbuf_mb */
 100         if ((mp = sp->rbuf_mb)) {       /* Get header for oldest data */
 101             KERNEL_DEBUG(DBG_ADSP_READ, 4, pb, mp, gbuf_msgsize(mp), gbuf_next(mp));
 102             sp->rbuf_mb = gbuf_next(mp);
 103             gbuf_next(mp) = 0;
 104             eom = 1;
 105         } else if ((mp = sp->crbuf_mb)) {
 106             KERNEL_DEBUG(DBG_ADSP_READ, 5, pb, mp, gbuf_msgsize(mp), gbuf_next(mp));
 107             sp->crbuf_mb = 0;
 108             eom = 0;
 109         }
 110
 111         /* Get the first (reqCount-actCount) bytes and tack them onto
 112            the end of pb->mp.  If eom is set, put the remainder of the
 113            data onto the front of sp->rbuf_mb, otherwise sp->crbuf_mb. */
 114         cnt = gbuf_msgsize(mp); /* # of data bytes in it. */
 115         if (cnt > (unsigned short)(pb->u.ioParams.reqCount - pb->u.ioParams.actCount)) {
 116             cnt = pb->u.ioParams.reqCount - pb->u.ioParams.actCount;
 117             /* m_split returns the tail */
 118             if (!(tmp = (gbuf_t *)m_split(mp, cnt, M_DONTWAIT))) {
 119                 cnt = 0;
 120                 tmp = mp;
 121             }
 122             if (eom) {
 123                 gbuf_next(tmp) = sp->rbuf_mb;
 124                 sp->rbuf_mb = tmp;
 125                 eom = 0;
 126             } else
 127                 sp->crbuf_mb = tmp;
 128         }
 129         if (cnt) {
 130             pb->u.ioParams.actCount += cnt;
 131             gbuf_linkb(pb->mp, mp);
 132         }
 133
 134         pb->u.ioParams.eom = eom;
 135         /*
 136          * Now clean up receive buffer to remove all of the data
 137          * we just copied
 138          */
 139         if ((sp->rbuf_mb == 0) &&
 140             (sp->crbuf_mb == 0)) /* no more data blocks */
 141             sp->rData = 0;
 142         /*
 143          * If we've filled the parameter block, unlink it from read
 144          * queue and complete it. We also need to do this if the connection
 145          * is closed && there is no more stuff to read.
 146          */
 147         if (eom || (pb->u.ioParams.actCount >= pb->u.ioParams.reqCount) ||
 148             ((sp->state == sClosed) && (!sp->rData)) ) {
 149               /* end of message, message is full, connection
 150                * is closed and all data has been delivered,
 151                * or we are not to "delay" data delivery.
 152                */
 153             pb->ioResult = 0;
 154             sp->rpb = pb->qLink; /* dequeue request */
 155             if (pb->ioc) {      /* data to be delivered at the time of the */
 156                 mp = gbuf_cont(pb->mp); /* ioctl call */
 157                 gbuf_cont(pb->mp) = 0;
 158                 gref = (gref_t *)pb->gref;
 159                 adspioc_ack(0, (gbuf_t *)pb->ioc, pb->gref);
 160                 dPrintf(D_M_ADSP, D_L_TRACE, ("    (pb->ioc) mp=%p\n", mp));
 161                 KERNEL_DEBUG(DBG_ADSP_READ, 0x0A, pb,  mp,
 162                              gbuf_next(mp), gbuf_cont(mp));
 163                 SndMsgUp(gref, mp);
 164                 dPrintf(D_M_ADSP, D_L_TRACE,
 165                         ("    (data) size req=%d\n", pb->u.ioParams.actCount));
 166                 KERNEL_DEBUG(DBG_ADSP_READ, 0x0B, pb, pb->ioc,
 167                              pb->u.ioParams.reqCount, pb->u.ioParams.actCount);
 168             } else {            /* complete an queued async request */
 169                 KERNEL_DEBUG(DBG_ADSP_READ, 0x0C, pb, sp,
 170                              pb->u.ioParams.actCount, sp->delay);
 171                 completepb(sp, pb);
 172             }
 173         }
 174     }   /* while */
 175
 176     if ((pb = sp->rpb)) {               /* if there is an outstanding request */
 177         dPrintf(D_M_ADSP, D_L_TRACE,
 178                  (" pb=0x%p, ioc=0x%p, reqCount=%d (no more data)\n",
 179                   pb, pb->ioc, pb->u.ioParams.reqCount));
 180         KERNEL_DEBUG(DBG_ADSP_READ, 0x0D, pb, pb->ioc,
 181                      pb->u.ioParams.reqCount, pb->u.ioParams.actCount);
 182
 183         if (sp->state == sClosed) {
 184             while (pb) {
 185                     KERNEL_DEBUG(DBG_ADSP_READ, 0x0E, pb, sp, pb->ioc, 0);
 186                     pb->ioResult = 0;
 187                     pb->u.ioParams.actCount = 0;
 188                     pb->u.ioParams.eom = 0;
 189                     sp->rpb = pb->qLink;
 190                     if (pb->ioc) {
 191                             adspioc_ack(0, (gbuf_t *)pb->ioc, pb->gref);
 192                     } else {
 193                             completepb(sp, pb);
 194                     }
 195                     pb = sp->rpb;
 196             }
 197         } else if (pb->ioc) {   /* if request not complete and this
 198                                  * is an active ioctl, release user */
 199             sp->rpb = pb->qLink;
 200             pb->ioResult = 1;
 201             tmp = gbuf_cont(pb->mp); /* detatch perhaps delayed data */
 202             gbuf_cont(pb->mp) = 0;
 203             if ((mp = gbuf_copym(pb->mp))) { /* otherwise, duplicate user request */
 204                     KERNEL_DEBUG(DBG_ADSP_READ, 0x0F, pb, sp, pb->mp, 0);
 205                     adspioc_ack(0, (gbuf_t *)pb->ioc, pb->gref);        /* release user */
 206                     pb = (struct adspcmd *)gbuf_rptr(mp); /* get new parameter block */
 207                     pb->ioc = 0;
 208                     pb->mp = mp;
 209                     gbuf_cont(pb->mp) = tmp; /* reattach data */
 210                     pb->qLink = sp->rpb; /* requeue the duplicate at the head */
 211                     sp->rpb = pb;
 212             } else {            /* there is no data left, but no space
 213                                  * to duplicate the parameter block, so
 214                                  * put what must be a non EOM message
 215                                  * back on the current receive queue, and
 216                                  * error out the user
 217                                  */
 218                     KERNEL_DEBUG(DBG_ADSP_READ, 0x10, pb, sp, pb->mp, 0);
 219                     if (tmp) {
 220                             sp->crbuf_mb = tmp;
 221                             sp->rData = 1;
 222                     }
 223                     pb->ioResult = errDSPQueueSize;
 224                     adspioc_ack(ENOBUFS, (gbuf_t *)pb->ioc, pb->gref);
 225             }
 226         }
 227     }
 228     /*
 229      * The receive window has opened.  If was previously closed, then we
 230      * need to notify the other guy that we now have room to receive more
 231      * data.  But, in order to cut down on lots of small data packets,
 232      * we'll wait until the recieve buffer  is /14 empy before telling
 233      * him that there's room in our receive buffer.
 234      */
 235     if (sp->rbufFull && (CalcRecvWdw(sp) > (sp->rbuflen >> 2))) {
 236         sp->rbufFull = 0;
 237         sp->sendDataAck = 1;
 238         sp->callSend = 1;
 239     }
 240
 241     KERNEL_DEBUG(DBG_ADSP_READ, 0x11, sp, 0, 0, 0);
 242     trace_mbufs(D_M_ADSP_LOW, "    eCQR m", sp->rbuf_mb);
 243     return 0;
 244 }
 245
 246 /*
 247  * CheckAttn
 248  *
 249  * Checks to see if there is any attention data and passes the data back
 250  * in the passed in pb.
 251  *
 252  * INPUTS:
 253  *      sp
 254  *      pb
 255  *
 256  * OUTPUTS:
 257  *
 258  */
 259 int CheckAttn(CCBPtr, struct adspcmd *);
 260
 261 int CheckAttn(sp, pb)           /* (CCBPtr sp) */
 262     register CCBPtr sp;
 263     register struct adspcmd *pb;
 264 {
 265     gbuf_t *mp;
 266     gref_t *gref = 0;
 267
 268     dPrintf(D_M_ADSP, D_L_TRACE,
 269             ("CheckAttn: sp=0x%x, pb=0x%x\n", (unsigned)sp, (unsigned)pb));
 270
 271     if ((mp = sp->attn_mb)) {
 272
 273         /*
 274          * Deliver the attention data to the user.
 275          */
 276         gref = (gref_t *)pb->gref;
 277         pb->u.attnParams.attnSize = sp->attnSize;
 278         pb->u.attnParams.attnCode = sp->attnCode;
 279         if (!sp->attnSize) {
 280             gbuf_freem(mp);
 281             mp = 0;
 282         }
 283         sp->userFlags &= ~eAttention;
 284         /*
 285          * Now clean up receive buffer to remove all of the data
 286          * we just copied
 287          */
 288         sp->attn_mb = 0;
 289         pb->ioResult = 0;
 290     } else {
 291         /*
 292          * No data...
 293          */
 294         pb->u.attnParams.attnSize = 0;
 295         pb->u.attnParams.attnCode = 0;
 296         pb->ioResult = 1;       /* not done */
 297     }
 298     adspioc_ack(0, (gbuf_t *)pb->ioc, pb->gref);
 299     if (mp) {
 300         SndMsgUp(gref, mp);
 301         }
 302     return 0;
 303 }
 304
 305 /*
 306  * adspRead
 307  *
 308  * INPUTS:
 309  *      --> sp                  stream pointer
 310  *      --> pb                  user request parameter block
 311  *
 312  * OUTPUTS:
 313  *      <-- actCount            actual number of bytes read
 314  *      <-- eom                 one if end-of-message, zero otherwise
 315  *
 316  * ERRORS:
 317  *      errRefNum               bad connection refnum
 318  *      errState
 319  *      errFwdReset             read terminated by forward reset
 320  *      errAborted              request aborted by Remove or Close call
 321  */
 322 int adspRead(sp, pb)            /* (DSPPBPtr pb) */
 323     register CCBPtr sp;
 324     register struct adspcmd *pb;
 325 {
 326     register gbuf_t *mp;
 327
 328     dPrintf(D_M_ADSP, D_L_TRACE,
 329             ("adspRead: sp=0x%x, pb=0x%x\n", (unsigned)sp, (unsigned)pb));
 330
 331     KERNEL_DEBUG(DBG_ADSP_READ, 0x12, sp, pb, sp->state, sp->rData);
 332
 333     if (sp == 0) {
 334         pb->ioResult = errRefNum;
 335         return EINVAL;
 336     }
 337
 338     /*
 339      * It's OK to read on a closed, or closing session
 340      */
 341     if (sp->state != sOpen && sp->state != sClosing && sp->state != sClosed) {
 342         pb->ioResult = errState;
 343         return EINVAL;
 344     }
 345     if (sp->rData && (sp->rpb == 0)) { /* if data, and no queue of pbs */
 346         qAddToEnd((struct qlink **)&sp->rpb, (struct qlink *)pb); /* deliver data to user directly */
 347         CheckReadQueue(sp);
 348     } else if ((pb->u.ioParams.reqCount == 0) && (sp->rpb == 0)) {
 349             /* empty read */
 350             pb->ioResult = 0;
 351             adspioc_ack(0, (gbuf_t *)pb->ioc, pb->gref);
 352             return 0;
 353     } else {
 354         pb->ioResult = 1;
 355         if ((mp = gbuf_copym(pb->mp))) { /* otherwise, duplicate user request */
 356                 adspioc_ack(0, (gbuf_t *)pb->ioc, pb->gref);    /* release user */
 357                 pb = (struct adspcmd *)gbuf_rptr(mp);   /* get new parameter block */
 358                 pb->ioc = 0;
 359                 pb->mp = mp;
 360                 qAddToEnd((struct qlink **)&sp->rpb, (struct qlink *)pb); /* and queue it for later */
 361         } else {
 362                 pb->ioResult = errDSPQueueSize;
 363                 return ENOBUFS;
 364         }
 365     }
 366
 367     if (sp->callSend) {
 368         CheckSend(sp);          /* If recv window opened, we might */
 369                                 /* send an unsolicited ACK. */
 370     }
 371     return 0;
 372 }
 373
 374 /*
 375  * dspReadAttention
 376  *
 377  * INPUTS:
 378  *      --> sp                  stream pointer
 379  *      --> pb                  user request parameter block
 380  *
 381  * OUTPUTS:
 382  *      <-- NONE
 383  *
 384  * ERRORS:
 385  *      errRefNum               bad connection refnum
 386  *      errState                connection is not in the right state
 387  */
 388 int adspReadAttention(sp, pb)           /* (DSPPBPtr pb) */
 389     register CCBPtr sp;
 390     register struct adspcmd *pb;
 391 {
 392     dPrintf(D_M_ADSP, D_L_TRACE,
 393             ("adspReadAttention: sp=0x%x, pb=0x%x\n", (unsigned)sp, (unsigned)pb));
 394     if (sp == 0) {
 395         pb->ioResult = errRefNum;
 396         return EINVAL;
 397     }
 398
 399     /*
 400      * It's OK to read on a closed, or closing session
 401      */
 402     if (sp->state != sOpen && sp->state != sClosing && sp->state != sClosed) {
 403         pb->ioResult = errState;
 404         return EINVAL;
 405     }
 406
 407     CheckAttn(sp, pb);          /* Anything in the attention queue */
 408     CheckReadQueue(sp);         /* check to see if receive window has opened */
 409     if (sp->callSend) {
 410         CheckSend(sp);          /* If recv window opened, we might */
 411                                 /* send an unsolicited ACK. */
 412         }
 413     return 0;
 414 } /* adspReadAttention */