1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */ 26 /* All Rights Reserved */ 27 28 29 30 /* 31 * Pseudo Terminal Slave Driver. 32 * 33 * The pseudo-tty subsystem simulates a terminal connection, where the master 34 * side represents the terminal and the slave represents the user process's 35 * special device end point. The master device is set up as a cloned device 36 * where its major device number is the major for the clone device and its minor 37 * device number is the major for the ptm driver. There are no nodes in the file 38 * system for master devices. The master pseudo driver is opened using the 39 * open(2) system call with /dev/ptmx as the device parameter. The clone open 40 * finds the next available minor device for the ptm major device. 41 * 42 * A master device is available only if it and its corresponding slave device 43 * are not already open. When the master device is opened, the corresponding 44 * slave device is automatically locked out. Only one open is allowed on a 45 * master device. Multiple opens are allowed on the slave device. After both 46 * the master and slave have been opened, the user has two file descriptors 47 * which are the end points of a full duplex connection composed of two streams 48 * which are automatically connected at the master and slave drivers. The user 49 * may then push modules onto either side of the stream pair. 50 * 51 * The master and slave drivers pass all messages to their adjacent queues. 52 * Only the M_FLUSH needs some processing. Because the read queue of one side 53 * is connected to the write queue of the other, the FLUSHR flag is changed to 54 * the FLUSHW flag and vice versa. When the master device is closed an M_HANGUP 55 * message is sent to the slave device which will render the device 56 * unusable. The process on the slave side gets the EIO when attempting to write 57 * on that stream but it will be able to read any data remaining on the stream 58 * head read queue. When all the data has been read, read() returns 0 59 * indicating that the stream can no longer be used. On the last close of the 60 * slave device, a 0-length message is sent to the master device. When the 61 * application on the master side issues a read() or getmsg() and 0 is returned, 62 * the user of the master device decides whether to issue a close() that 63 * dismantles the pseudo-terminal subsystem. If the master device is not closed, 64 * the pseudo-tty subsystem will be available to another user to open the slave 65 * device. 66 * 67 * Synchronization: 68 * 69 * All global data synchronization between ptm/pts is done via global 70 * ptms_lock mutex which is initialized at system boot time from 71 * ptms_initspace (called from space.c). 72 * 73 * Individual fields of pt_ttys structure (except ptm_rdq, pts_rdq and 74 * pt_nullmsg) are protected by pt_ttys.pt_lock mutex. 75 * 76 * PT_ENTER_READ/PT_ENTER_WRITE are reference counter based read-write locks 77 * which allow reader locks to be reacquired by the same thread (usual 78 * reader/writer locks can't be used for that purpose since it is illegal for 79 * a thread to acquire a lock it already holds, even as a reader). The sole 80 * purpose of these macros is to guarantee that the peer queue will not 81 * disappear (due to closing peer) while it is used. It is safe to use 82 * PT_ENTER_READ/PT_EXIT_READ brackets across calls like putq/putnext (since 83 * they are not real locks but reference counts). 84 * 85 * PT_ENTER_WRITE/PT_EXIT_WRITE brackets are used ONLY in master/slave 86 * open/close paths to modify ptm_rdq and pts_rdq fields. These fields should 87 * be set to appropriate queues *after* qprocson() is called during open (to 88 * prevent peer from accessing the queue with incomplete plumbing) and set to 89 * NULL before qprocsoff() is called during close. 90 * 91 * The pt_nullmsg field is only used in open/close routines and it is also 92 * protected by PT_ENTER_WRITE/PT_EXIT_WRITE brackets to avoid extra mutex 93 * holds. 94 * 95 * Lock Ordering: 96 * 97 * If both ptms_lock and per-pty lock should be held, ptms_lock should always 98 * be entered first, followed by per-pty lock. 99 * 100 * See ptms.h, ptm.c and ptms_conf.c fore more information. 101 * 102 */ 103 104 #include <sys/types.h> 105 #include <sys/param.h> 106 #include <sys/sysmacros.h> 107 #include <sys/stream.h> 108 #include <sys/stropts.h> 109 #include <sys/stat.h> 110 #include <sys/errno.h> 111 #include <sys/debug.h> 112 #include <sys/cmn_err.h> 113 #include <sys/ptms.h> 114 #include <sys/systm.h> 115 #include <sys/modctl.h> 116 #include <sys/conf.h> 117 #include <sys/ddi.h> 118 #include <sys/sunddi.h> 119 #include <sys/cred.h> 120 #include <sys/zone.h> 121 122 #ifdef DEBUG 123 int pts_debug = 0; 124 #define DBG(a) if (pts_debug) cmn_err(CE_NOTE, a) 125 #else 126 #define DBG(a) 127 #endif 128 129 static int ptsopen(queue_t *, dev_t *, int, int, cred_t *); 130 static int ptsclose(queue_t *, int, cred_t *); 131 static void ptswput(queue_t *, mblk_t *); 132 static void ptsrsrv(queue_t *); 133 static void ptswsrv(queue_t *); 134 135 /* 136 * Slave Stream Pseudo Terminal Module: stream data structure definitions 137 */ 138 static struct module_info pts_info = { 139 0xface, 140 "pts", 141 0, 142 512, 143 512, 144 128 145 }; 146 147 static struct qinit ptsrint = { 148 NULL, 149 (int (*)()) ptsrsrv, 150 ptsopen, 151 ptsclose, 152 NULL, 153 &pts_info, 154 NULL 155 }; 156 157 static struct qinit ptswint = { 158 (int (*)()) ptswput, 159 (int (*)()) ptswsrv, 160 NULL, 161 NULL, 162 NULL, 163 &pts_info, 164 NULL 165 }; 166 167 static struct streamtab ptsinfo = { 168 &ptsrint, 169 &ptswint, 170 NULL, 171 NULL 172 }; 173 174 static int pts_devinfo(dev_info_t *, ddi_info_cmd_t, void *, void **); 175 static int pts_attach(dev_info_t *, ddi_attach_cmd_t); 176 static int pts_detach(dev_info_t *, ddi_detach_cmd_t); 177 178 #define PTS_CONF_FLAG (D_NEW | D_MP) 179 180 /* 181 * this will define (struct cb_ops cb_pts_ops) and (struct dev_ops pts_ops) 182 */ 183 DDI_DEFINE_STREAM_OPS(pts_ops, nulldev, nulldev, \ 184 pts_attach, pts_detach, nodev, \ 185 pts_devinfo, PTS_CONF_FLAG, &ptsinfo, ddi_quiesce_not_supported); 186 187 /* 188 * Module linkage information for the kernel. 189 */ 190 191 static struct modldrv modldrv = { 192 &mod_driverops, /* Type of module. This one is a pseudo driver */ 193 "Slave Stream Pseudo Terminal driver 'pts'", 194 &pts_ops, /* driver ops */ 195 }; 196 197 static struct modlinkage modlinkage = { 198 MODREV_1, 199 { &modldrv, NULL } 200 }; 201 202 int 203 _init(void) 204 { 205 int rc; 206 207 if ((rc = mod_install(&modlinkage)) == 0) 208 ptms_init(); 209 return (rc); 210 } 211 212 213 int 214 _fini(void) 215 { 216 return (mod_remove(&modlinkage)); 217 } 218 219 int 220 _info(struct modinfo *modinfop) 221 { 222 return (mod_info(&modlinkage, modinfop)); 223 } 224 225 static int 226 pts_attach(dev_info_t *devi, ddi_attach_cmd_t cmd) 227 { 228 if (cmd != DDI_ATTACH) 229 return (DDI_FAILURE); 230 231 mutex_enter(&ptms_lock); 232 pts_dip = devi; 233 mutex_exit(&ptms_lock); 234 235 return (DDI_SUCCESS); 236 } 237 238 /*ARGSUSED*/ 239 static int 240 pts_detach(dev_info_t *devi, ddi_detach_cmd_t cmd) 241 { 242 if (cmd != DDI_DETACH) 243 return (DDI_FAILURE); 244 245 /* 246 * For now, pts cannot be detached. 247 */ 248 return (DDI_FAILURE); 249 } 250 251 /*ARGSUSED*/ 252 static int 253 pts_devinfo(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg, 254 void **result) 255 { 256 int error; 257 258 switch (infocmd) { 259 case DDI_INFO_DEVT2DEVINFO: 260 if (pts_dip == NULL) { 261 error = DDI_FAILURE; 262 } else { 263 *result = (void *)pts_dip; 264 error = DDI_SUCCESS; 265 } 266 break; 267 case DDI_INFO_DEVT2INSTANCE: 268 *result = (void *)0; 269 error = DDI_SUCCESS; 270 break; 271 default: 272 error = DDI_FAILURE; 273 } 274 return (error); 275 } 276 277 /* ARGSUSED */ 278 /* 279 * Open the slave device. Reject a clone open and do not allow the 280 * driver to be pushed. If the slave/master pair is locked or if 281 * the master is not open, return EACCESS. 282 * Upon success, store the write queue pointer in private data and 283 * set the PTSOPEN bit in the pt_state field. 284 */ 285 static int 286 ptsopen( 287 queue_t *rqp, /* pointer to the read side queue */ 288 dev_t *devp, /* pointer to stream tail's dev */ 289 int oflag, /* the user open(2) supplied flags */ 290 int sflag, /* open state flag */ 291 cred_t *credp) /* credentials */ 292 { 293 struct pt_ttys *ptsp; 294 mblk_t *mp; 295 mblk_t *mop; /* ptr to a setopts message block */ 296 minor_t dminor = getminor(*devp); 297 struct stroptions *sop; 298 299 DDBG("entering ptsopen(%d)", dminor); 300 301 if (sflag != 0) { 302 return (EINVAL); 303 } 304 305 mutex_enter(&ptms_lock); 306 ptsp = ptms_minor2ptty(dminor); 307 308 if (ptsp == NULL) { 309 mutex_exit(&ptms_lock); 310 return (ENXIO); 311 } 312 mutex_enter(&ptsp->pt_lock); 313 314 /* 315 * Prevent opens from zones other than the one blessed by ptm. We 316 * can't even allow the global zone to open all pts's, as it would 317 * otherwise inproperly be able to claim pts's already opened by zones. 318 */ 319 if (ptsp->pt_zoneid != getzoneid()) { 320 mutex_exit(&ptsp->pt_lock); 321 mutex_exit(&ptms_lock); 322 return (EPERM); 323 } 324 325 /* 326 * Allow reopen of this device. 327 */ 328 if (rqp->q_ptr != NULL) { 329 ASSERT(rqp->q_ptr == ptsp); 330 ASSERT(ptsp->pts_rdq == rqp); 331 mutex_exit(&ptsp->pt_lock); 332 mutex_exit(&ptms_lock); 333 return (0); 334 } 335 336 DDBGP("ptsopen: p = %p\n", (uintptr_t)ptsp); 337 DDBG("ptsopen: state = %x\n", ptsp->pt_state); 338 339 340 ASSERT(ptsp->pt_minor == dminor); 341 342 if ((ptsp->pt_state & PTLOCK) || !(ptsp->pt_state & PTMOPEN)) { 343 mutex_exit(&ptsp->pt_lock); 344 mutex_exit(&ptms_lock); 345 return (EAGAIN); 346 } 347 348 /* 349 * if already, open simply return... 350 */ 351 if (ptsp->pt_state & PTSOPEN) { 352 ASSERT(rqp->q_ptr == ptsp); 353 ASSERT(ptsp->pts_rdq == rqp); 354 mutex_exit(&ptsp->pt_lock); 355 mutex_exit(&ptms_lock); 356 return (0); 357 } 358 359 /* 360 * Allocate message block for setting stream head options. 361 */ 362 if ((mop = allocb(sizeof (struct stroptions), BPRI_MED)) == NULL) { 363 mutex_exit(&ptsp->pt_lock); 364 mutex_exit(&ptms_lock); 365 return (ENOMEM); 366 } 367 368 /* 369 * Slave should send zero-length message to a master when it is 370 * closing. If memory is low at that time, master will not detect slave 371 * closes, this pty will not be deallocated. So, preallocate this 372 * zero-length message block early. 373 */ 374 if ((mp = allocb(0, BPRI_MED)) == NULL) { 375 mutex_exit(&ptsp->pt_lock); 376 mutex_exit(&ptms_lock); 377 freemsg(mop); 378 return (ENOMEM); 379 } 380 381 ptsp->pt_state |= PTSOPEN; 382 383 WR(rqp)->q_ptr = rqp->q_ptr = ptsp; 384 385 mutex_exit(&ptsp->pt_lock); 386 mutex_exit(&ptms_lock); 387 388 qprocson(rqp); 389 390 /* 391 * After qprocson pts driver is fully plumbed into the stream and can 392 * send/receive messages. Setting pts_rdq will allow master side to send 393 * messages to the slave. This setting can't occur before qprocson() is 394 * finished because slave is not ready to process them. 395 */ 396 PT_ENTER_WRITE(ptsp); 397 ptsp->pts_rdq = rqp; 398 ASSERT(ptsp->pt_nullmsg == NULL); 399 ptsp->pt_nullmsg = mp; 400 PT_EXIT_WRITE(ptsp); 401 402 /* 403 * set up hi/lo water marks on stream head read queue 404 * and add controlling tty if not set 405 */ 406 407 mop->b_datap->db_type = M_SETOPTS; 408 mop->b_wptr += sizeof (struct stroptions); 409 sop = (struct stroptions *)mop->b_rptr; 410 sop->so_flags = SO_HIWAT | SO_LOWAT | SO_ISTTY; 411 sop->so_hiwat = 512; 412 sop->so_lowat = 256; 413 putnext(rqp, mop); 414 415 return (0); 416 } 417 418 419 420 /* 421 * Find the address to private data identifying the slave's write 422 * queue. Send a 0-length msg up the slave's read queue to designate 423 * the master is closing. Uattach the master from the slave by nulling 424 * out master's write queue field in private data. 425 */ 426 /*ARGSUSED1*/ 427 static int 428 ptsclose(queue_t *rqp, int flag, cred_t *credp) 429 { 430 struct pt_ttys *ptsp; 431 queue_t *wqp; 432 mblk_t *mp; 433 mblk_t *bp; 434 435 /* 436 * q_ptr should never be NULL in the close routine and it is checked in 437 * DEBUG kernel by ASSERT. For non-DEBUG kernel the attempt is made to 438 * behave gracefully. 439 */ 440 ASSERT(rqp->q_ptr != NULL); 441 if (rqp->q_ptr == NULL) { 442 qprocsoff(rqp); 443 return (0); 444 } 445 446 ptsp = (struct pt_ttys *)rqp->q_ptr; 447 448 /* 449 * Slave is going to close and doesn't want any new messages coming 450 * from the master side, so set pts_rdq to NULL. This should be done 451 * before call to qprocsoff() since slave can't process additional 452 * messages from the master after qprocsoff is called. 453 */ 454 PT_ENTER_WRITE(ptsp); 455 mp = ptsp->pt_nullmsg; 456 ptsp->pt_nullmsg = NULL; 457 ptsp->pts_rdq = NULL; 458 PT_EXIT_WRITE(ptsp); 459 460 /* 461 * Drain the ouput 462 */ 463 wqp = WR(rqp); 464 PT_ENTER_READ(ptsp); 465 while ((bp = getq(wqp)) != NULL) { 466 if (ptsp->ptm_rdq) { 467 putnext(ptsp->ptm_rdq, bp); 468 } else if (bp->b_datap->db_type == M_IOCTL) { 469 bp->b_datap->db_type = M_IOCNAK; 470 freemsg(bp->b_cont); 471 bp->b_cont = NULL; 472 qreply(wqp, bp); 473 } else { 474 freemsg(bp); 475 } 476 } 477 /* 478 * qenable master side write queue so that it can flush 479 * its messages as slaves's read queue is going away 480 */ 481 if (ptsp->ptm_rdq) { 482 if (mp) 483 putnext(ptsp->ptm_rdq, mp); 484 else 485 qenable(WR(ptsp->ptm_rdq)); 486 } else 487 freemsg(mp); 488 PT_EXIT_READ(ptsp); 489 490 qprocsoff(rqp); 491 492 rqp->q_ptr = NULL; 493 WR(rqp)->q_ptr = NULL; 494 495 ptms_close(ptsp, PTSOPEN | PTSTTY); 496 497 return (0); 498 } 499 500 501 /* 502 * The wput procedure will only handle flush messages. 503 * All other messages are queued and the write side 504 * service procedure sends them off to the master side. 505 */ 506 static void 507 ptswput(queue_t *qp, mblk_t *mp) 508 { 509 struct pt_ttys *ptsp; 510 struct iocblk *iocp; 511 unsigned char type = mp->b_datap->db_type; 512 513 DBG(("entering ptswput\n")); 514 ASSERT(qp->q_ptr); 515 516 ptsp = (struct pt_ttys *)qp->q_ptr; 517 PT_ENTER_READ(ptsp); 518 if (ptsp->ptm_rdq == NULL) { 519 DBG(("in write put proc but no master\n")); 520 /* 521 * NAK ioctl as slave side read queue is gone. 522 * Or else free the message. 523 */ 524 if (mp->b_datap->db_type == M_IOCTL) { 525 mp->b_datap->db_type = M_IOCNAK; 526 freemsg(mp->b_cont); 527 mp->b_cont = NULL; 528 qreply(qp, mp); 529 } else 530 freemsg(mp); 531 PT_EXIT_READ(ptsp); 532 return; 533 } 534 535 if (type >= QPCTL) { 536 switch (type) { 537 538 /* 539 * if write queue request, flush slave's write 540 * queue and send FLUSHR to ptm. If read queue 541 * request, send FLUSHR to ptm. 542 */ 543 case M_FLUSH: 544 DBG(("pts got flush request\n")); 545 if (*mp->b_rptr & FLUSHW) { 546 547 DBG(("got FLUSHW, flush pts write Q\n")); 548 if (*mp->b_rptr & FLUSHBAND) 549 /* 550 * if it is a FLUSHBAND, do flushband. 551 */ 552 flushband(qp, *(mp->b_rptr + 1), FLUSHDATA); 553 else 554 flushq(qp, FLUSHDATA); 555 556 *mp->b_rptr &= ~FLUSHW; 557 if ((*mp->b_rptr & FLUSHR) == 0) { 558 /* 559 * FLUSHW only. Change to FLUSHR and putnext 560 * to ptm, then we are done. 561 */ 562 *mp->b_rptr |= FLUSHR; 563 if (ptsp->ptm_rdq) 564 putnext(ptsp->ptm_rdq, mp); 565 break; 566 } else { 567 mblk_t *nmp; 568 569 /* It is a FLUSHRW. Duplicate the mblk */ 570 nmp = copyb(mp); 571 if (nmp) { 572 /* 573 * Change FLUSHW to FLUSHR before 574 * putnext to ptm. 575 */ 576 DBG(("putnext nmp(FLUSHR) to ptm\n")); 577 *nmp->b_rptr |= FLUSHR; 578 if (ptsp->ptm_rdq) 579 putnext(ptsp->ptm_rdq, nmp); 580 } 581 } 582 } 583 /* 584 * Since the packet module will toss any 585 * M_FLUSHES sent to the master's stream head 586 * read queue, we simply turn it around here. 587 */ 588 if (*mp->b_rptr & FLUSHR) { 589 ASSERT(RD(qp)->q_first == NULL); 590 DBG(("qreply(qp) turning FLUSHR around\n")); 591 qreply(qp, mp); 592 } else { 593 freemsg(mp); 594 } 595 break; 596 597 case M_READ: 598 /* Caused by ldterm - can not pass to master */ 599 freemsg(mp); 600 break; 601 602 default: 603 if (ptsp->ptm_rdq) 604 putnext(ptsp->ptm_rdq, mp); 605 break; 606 } 607 PT_EXIT_READ(ptsp); 608 return; 609 } 610 611 switch (type) { 612 613 case M_IOCTL: 614 /* 615 * For case PTSSTTY set the flag PTSTTY and ACK 616 * the ioctl so that the user program can push 617 * the associated modules to get tty semantics. 618 * See bugid 4025044 619 */ 620 iocp = (struct iocblk *)mp->b_rptr; 621 switch (iocp->ioc_cmd) { 622 default: 623 break; 624 625 case PTSSTTY: 626 if (ptsp->pt_state & PTSTTY) { 627 mp->b_datap->db_type = M_IOCNAK; 628 iocp->ioc_error = EEXIST; 629 } else { 630 mp->b_datap->db_type = M_IOCACK; 631 mutex_enter(&ptsp->pt_lock); 632 ptsp->pt_state |= PTSTTY; 633 mutex_exit(&ptsp->pt_lock); 634 iocp->ioc_error = 0; 635 } 636 iocp->ioc_count = 0; 637 qreply(qp, mp); 638 PT_EXIT_READ(ptsp); 639 return; 640 } 641 642 default: 643 /* 644 * send other messages to the master 645 */ 646 DBG(("put msg on slave's write queue\n")); 647 (void) putq(qp, mp); 648 break; 649 } 650 651 PT_EXIT_READ(ptsp); 652 DBG(("return from ptswput()\n")); 653 } 654 655 656 /* 657 * enable the write side of the master. This triggers the 658 * master to send any messages queued on its write side to 659 * the read side of this slave. 660 */ 661 static void 662 ptsrsrv(queue_t *qp) 663 { 664 struct pt_ttys *ptsp; 665 666 DBG(("entering ptsrsrv\n")); 667 ASSERT(qp->q_ptr); 668 669 ptsp = (struct pt_ttys *)qp->q_ptr; 670 PT_ENTER_READ(ptsp); 671 if (ptsp->ptm_rdq == NULL) { 672 DBG(("in read srv proc but no master\n")); 673 PT_EXIT_READ(ptsp); 674 return; 675 } 676 qenable(WR(ptsp->ptm_rdq)); 677 PT_EXIT_READ(ptsp); 678 DBG(("leaving ptsrsrv\n")); 679 } 680 681 /* 682 * If there are messages on this queue that can be sent to 683 * master, send them via putnext(). Else, if queued messages 684 * cannot be sent, leave them on this queue. If priority 685 * messages on this queue, send them to master no matter what. 686 */ 687 static void 688 ptswsrv(queue_t *qp) 689 { 690 struct pt_ttys *ptsp; 691 queue_t *ptm_rdq; 692 mblk_t *mp; 693 694 DBG(("entering ptswsrv\n")); 695 ASSERT(qp->q_ptr); 696 697 ptsp = (struct pt_ttys *)qp->q_ptr; 698 PT_ENTER_READ(ptsp); 699 if (ptsp->ptm_rdq == NULL) { 700 DBG(("in write srv proc but no master\n")); 701 /* 702 * Free messages on the write queue and send 703 * NAK for any M_IOCTL type messages to wakeup 704 * the user process waiting for ACK/NAK from 705 * the ioctl invocation 706 */ 707 while ((mp = getq(qp)) != NULL) { 708 if (mp->b_datap->db_type == M_IOCTL) { 709 mp->b_datap->db_type = M_IOCNAK; 710 freemsg(mp->b_cont); 711 mp->b_cont = NULL; 712 qreply(qp, mp); 713 } else 714 freemsg(mp); 715 } 716 PT_EXIT_READ(ptsp); 717 return; 718 } else { 719 ptm_rdq = ptsp->ptm_rdq; 720 } 721 722 /* 723 * while there are messages on this write queue... 724 */ 725 while ((mp = getq(qp)) != NULL) { 726 /* 727 * if don't have control message and cannot put 728 * msg. on master's read queue, put it back on 729 * this queue. 730 */ 731 if (mp->b_datap->db_type <= QPCTL && 732 !bcanputnext(ptm_rdq, mp->b_band)) { 733 DBG(("put msg. back on Q\n")); 734 (void) putbq(qp, mp); 735 break; 736 } 737 /* 738 * else send the message up master's stream 739 */ 740 DBG(("send message to master\n")); 741 putnext(ptm_rdq, mp); 742 } 743 DBG(("leaving ptswsrv\n")); 744 PT_EXIT_READ(ptsp); 745 }