usr/src/lib/libnsl/rpc/svc_run.c

   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 /*
  23  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26 /*
  27  * Copyright 2014 Nexenta Systems, Inc.  All rights reserved.
  28  */
  29
  30 /* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
  31 /* All Rights Reserved */
  32 /*
  33  * Portions of this source code were derived from Berkeley
  34  * 4.3 BSD under license from the Regents of the University of
  35  * California.
  36  */
  37
  38 /*
  39  * This is the rpc server side idle loop
  40  * Wait for input, call server program.
  41  */
  42 #include "mt.h"
  43 #include "rpc_mt.h"
  44 #include <stdlib.h>
  45 #include <unistd.h>
  46 #include <signal.h>
  47 #include <rpc/rpc.h>
  48 #include <errno.h>
  49 #include <sys/poll.h>
  50 #include <sys/types.h>
  51 #include <syslog.h>
  52 #include <thread.h>
  53 #include <assert.h>
  54 #include <libintl.h>
  55 #include <values.h>
  56
  57 extern const char __nsl_dom[];
  58
  59 extern int __rpc_compress_pollfd(int, pollfd_t *, pollfd_t *);
  60 extern bool_t __is_a_userfd(int P_fd);
  61 extern void   __destroy_userfd();
  62 extern void clear_pollfd(int);
  63 extern void set_pollfd(int /* fd */, short /* events */);
  64 extern void svc_getreq_poll();
  65 extern void (*__proc_cleanup_cb)();
  66
  67 static void start_threads();
  68 static void create_pipe();
  69 static void clear_pipe();
  70 static int select_next_pollfd();
  71 static SVCXPRT *make_xprt_copy();
  72 static void _svc_run_mt();
  73 static void _svc_run();
  74
  75 int _svc_prog_dispatch();
  76 static void _svc_done_private();
  77
  78 extern rwlock_t svc_fd_lock;
  79 extern mutex_t  svc_door_mutex;
  80 extern cond_t   svc_door_waitcv;
  81 extern int      svc_ndoorfds;
  82 extern void     __svc_cleanup_door_xprts();
  83 extern void     __svc_free_xprtlist();
  84 extern void     __svc_getreq_user(struct pollfd *);
  85
  86 /*
  87  * Maximum fragment size allowed for connection oriented connections.
  88  * Zero means that no maximum size limit has been requested.
  89  */
  90 int __rpc_connmaxrec = 0;
  91
  92 /* Inter-Record Timeout in secs for non-blocked connection RPC */
  93 int __rpc_irtimeout = 35;
  94
  95 /*
  96  * Request exclusive access to tcp and udp non-priv ports bound with a
  97  * wildcard addr.
  98  */
  99 bool_t __rpc_tp_exclbind = FALSE;
 100
 101 /*
 102  * Maximum number of outstanding connection indications (listen backlog).
 103  */
 104 static int __svc_lstnbklog = 64;        /* Chosen Arbitrarily */
 105
 106 /*
 107  * XXX - eventually, all mutexes and their initializations static
 108  */
 109
 110 /*
 111  * Variables used for MT
 112  */
 113 int svc_mt_mode;                /* multi-threading mode */
 114
 115 int svc_pipe[2];        /* pipe for breaking out of poll: read(0), write(1) */
 116
 117 /* BEGIN PROTECTED BY svc_mutex */
 118
 119 static int svc_thr_max = 16;    /* default maximum number of threads allowed */
 120
 121 static int svc_thr_total;       /* current number of threads */
 122
 123 static int svc_thr_active;      /* current number of threads active */
 124
 125 /* circular array of file descriptors with pending data */
 126
 127 #define CIRCULAR_BUFSIZE        1024
 128
 129 static int svc_pending_fds[CIRCULAR_BUFSIZE+1]; /* fds with pending data */
 130
 131 static int svc_next_pending;                    /* next one to be processed */
 132
 133 static int svc_last_pending;                    /* last one in list */
 134
 135 static int svc_total_pending;                   /* total in list */
 136
 137 static int svc_thr_total_creates;       /* total created - stats */
 138
 139 static int svc_thr_total_create_errors; /* total create errors - stats */
 140
 141 static int svc_waiters;         /* number of waiting threads */
 142
 143 /* END PROTECTED BY svc_mutex */
 144
 145 /* BEGIN PROTECTED BY svc_fd_lock: */
 146
 147 int svc_nfds;           /* total number of active file descriptors */
 148
 149 int svc_nfds_set;       /* total number of fd bits set in svc_fdset */
 150
 151 int svc_max_fd = 0;     /* largest active file descriptor */
 152
 153 int svc_npollfds;       /* total number of active pollfds */
 154
 155 int svc_npollfds_set;   /* total number of pollfd set in svc_pollfd */
 156
 157 int svc_max_pollfd;     /* largest active pollfd so far */
 158
 159 int svc_pollfd_allocd;  /* number of pollfd structures allocated */
 160
 161 /* END PROTECTED BY svc_fd_lock: */
 162
 163 /* BEGIN PROTECTED BY svc_thr_mutex */
 164
 165 #define POLLSET_EXTEND  256
 166 static int svc_pollset_allocd;
 167 static struct pollfd *svc_pollset;
 168                                 /*
 169                                  * array of file descriptors currently active
 170                                  */
 171 static int svc_polled;          /* no of fds polled in last poll() - input */
 172
 173 static int svc_pollfds;         /* no of active fds in last poll() - output */
 174
 175 static int svc_next_pollfd;     /* next fd  to processin svc_pollset */
 176
 177 bool_t svc_polling;             /* true if a thread is polling */
 178
 179 /* END PROTECTED BY svc_thr_mutex */
 180
 181 /* BEGIN PROTECTED BY svc_exit_mutex */
 182
 183 static bool_t svc_exit_done = TRUE;
 184
 185 /* END PROTECTED BY svc_exit_mutex */
 186
 187 /* VARIABLES PROTECTED BY svc_mutex:
 188         svc_thr_total, svc_thr_active, svc_pending_fds, svc_next_pending,
 189         svc_last_pending, svc_total_pending, svc_thr_total_creates,
 190         svc_thr_total_create_errors,
 191         svcxprt_list_t::next, svcxprt_ext_t::my_xlist,
 192         svc_thr_max, svc_waiters
 193  */
 194
 195 /* VARIABLES PROTECTED BY svc_fd_lock:
 196         svc_xports, svc_fdset, svc_nfds, svc_nfds_set, svc_max_fd,
 197         svc_pollfd, svc_npollfds, svc_npollfds_set, svc_max_pollfd
 198  */
 199
 200 /* VARIABLES PROTECTED BY svc_thr_mutex:
 201         svc_pollset, svc_pollfds, svc_next_pollfd, svc_polling
 202         svc_pollset_allocd, svc_polled
 203  */
 204
 205 /* VARIABLES PROTECTED BY svc_exit_mutex:
 206         svc_exit_done
 207  */
 208
 209 /* VARIABLES READABLE WITHOUT LOCK:
 210         svc_thr_total, svc_thr_active, svc_thr_total_creates,
 211         svc_thr_total_create_errors,
 212         svc_xports, svc_nfds, svc_nfds_set, svc_max_fd,
 213         svc_npollfds, svc_npollfds_set, svc_max_pollfd,
 214         svc_pollfds, svc_next_pollfd, svc_exit_done, svc_polling,
 215         svc_thr_max, svc_waiters
 216  */
 217
 218 /* VARIABLES PROTECTED BY "program_logic":
 219         rpc_msg::, svc_req::, svcxprt_ext_t::flags, svc_mt_mode,
 220         svcxprt_ext_t::parent
 221  */
 222
 223 /* LOCK ORDER:
 224         svc_exit_mutex, svc_thr_mutex, svc_mutex, svc_fd_lock
 225  */
 226
 227
 228 void
 229 svc_run(void)
 230 {
 231         /* NO OTHER THREADS ARE RUNNING */
 232
 233         svc_exit_done = FALSE;
 234
 235         while ((svc_npollfds > 0 || svc_ndoorfds > 0) && !svc_exit_done) {
 236                 if (svc_npollfds > 0) {
 237                         switch (svc_mt_mode) {
 238                         case RPC_SVC_MT_NONE:
 239                                 _svc_run();
 240                                 break;
 241                         default:
 242                                 _svc_run_mt();
 243                                 break;
 244                         }
 245                         continue;
 246                 }
 247
 248                 (void) mutex_lock(&svc_door_mutex);
 249                 if (svc_ndoorfds > 0)
 250                         (void) cond_wait(&svc_door_waitcv, &svc_door_mutex);
 251                 (void) mutex_unlock(&svc_door_mutex);
 252         }
 253 }
 254
 255
 256 /*
 257  *      This function causes svc_run() to exit by destroying all
 258  *      service handles.
 259  */
 260 void
 261 svc_exit(void)
 262 {
 263         SVCXPRT *xprt;
 264         int fd;
 265         char dummy;
 266
 267         /* NO LOCKS HELD */
 268
 269         (void) mutex_lock(&svc_exit_mutex);
 270         if (svc_exit_done) {
 271                 (void) mutex_unlock(&svc_exit_mutex);
 272                 return;
 273         }
 274         svc_exit_done = TRUE;
 275         for (fd = 0; fd < svc_max_pollfd; fd++) {
 276                 xprt = svc_xports[fd];
 277                 if (xprt) {
 278                         SVC_DESTROY(xprt);
 279                 }
 280         }
 281         __svc_free_xprtlist();
 282         __svc_cleanup_door_xprts();
 283         (void) mutex_unlock(&svc_exit_mutex);
 284
 285         if (svc_mt_mode != RPC_SVC_MT_NONE) {
 286                 (void) mutex_lock(&svc_mutex);
 287                 (void) cond_broadcast(&svc_thr_fdwait);
 288                 (void) mutex_unlock(&svc_mutex);
 289
 290                 (void) write(svc_pipe[1], &dummy, sizeof (dummy));
 291         }
 292
 293         (void) mutex_lock(&svc_door_mutex);
 294         (void) cond_signal(&svc_door_waitcv);   /* wake up door dispatching */
 295         (void) mutex_unlock(&svc_door_mutex);
 296
 297         /* destroy reactor information if any */
 298         __destroy_userfd();
 299 }
 300
 301
 302 /*
 303  * this funtion is called with svc_fd_lock and svc_thr_mutex
 304  */
 305
 306 static int
 307 alloc_pollset(int npollfds)
 308 {
 309         if (npollfds > svc_pollset_allocd) {
 310                 pollfd_t *tmp;
 311                 do {
 312                         svc_pollset_allocd += POLLSET_EXTEND;
 313                 } while (npollfds > svc_pollset_allocd);
 314                 tmp = realloc(svc_pollset,
 315                     sizeof (pollfd_t) * svc_pollset_allocd);
 316                 if (tmp == NULL) {
 317                         syslog(LOG_ERR, "alloc_pollset: out of memory");
 318                         return (-1);
 319                 }
 320                 svc_pollset = tmp;
 321         }
 322         return (0);
 323 }
 324
 325 static void
 326 _svc_run(void)
 327 {
 328         sigset_t set, oldset;
 329         int npollfds;
 330         int i;
 331
 332         /*
 333          * Block SIGALRM while doing work.  Unblock it while doing poll().
 334          * This is so that services like rpc.rstatd can cause the poll()
 335          * to be interrupted due to alarm() but that we don't end up in
 336          * an MT-unsafe signal handler at an inopportune time.
 337          */
 338         (void) sigemptyset(&set);
 339         (void) sigaddset(&set, SIGALRM);
 340         (void) sigprocmask(SIG_BLOCK, &set, &oldset);
 341         while (!svc_exit_done) {
 342                 /*
 343                  * Check whether there is any server fd on which we may want
 344                  * to wait.
 345                  */
 346                 (void) rw_rdlock(&svc_fd_lock);
 347                 if (alloc_pollset(svc_npollfds) == -1)
 348                         break;
 349                 npollfds = __rpc_compress_pollfd(svc_max_pollfd,
 350                     svc_pollfd, svc_pollset);
 351                 (void) rw_unlock(&svc_fd_lock);
 352                 if (npollfds == 0)
 353                         break;  /* None waiting, hence return */
 354
 355                 (void) sigprocmask(SIG_SETMASK, &oldset, NULL);
 356                 i = poll(svc_pollset, npollfds, -1);
 357                 (void) sigprocmask(SIG_BLOCK, &set, &oldset);
 358                 switch (i) {
 359                 case -1:
 360                         /*
 361                          * We ignore all errors, continuing with the assumption
 362                          * that it was set by the signal handlers (or any
 363                          * other outside event) and not caused by poll().
 364                          */
 365                 case 0:
 366                         continue;
 367                 default:
 368                         svc_getreq_poll(svc_pollset, i);
 369                 }
 370         }
 371         (void) sigprocmask(SIG_SETMASK, &oldset, NULL);
 372 }
 373
 374 /*
 375  * In _svc_run_mt, myfd is linked with mypollfd
 376  * svc_pollset[mypollfd].fd == myfd
 377  * However, in some cases, the link can not be made, thus we define the
 378  * following values for these special cases
 379  */
 380 enum {
 381         INVALID_POLLFD  = -200,
 382         FD_FROM_PENDING
 383 };
 384
 385 static void
 386 _svc_run_mt(void)
 387 {
 388         int npollfds;
 389         int n_polled, dispatch;
 390
 391         static bool_t first_time = TRUE;
 392         bool_t main_thread = FALSE;
 393         int n_new;
 394         int myfd, mypollfd;
 395         SVCXPRT *parent_xprt, *xprt;
 396
 397         /*
 398          * Server is multi-threaded.  Do "first time" initializations.
 399          * Since only one thread exists in the beginning, there's no
 400          * need for mutex protection for first time initializations.
 401          */
 402         if (first_time) {
 403                 first_time = FALSE;
 404                 main_thread = TRUE;
 405                 svc_thr_total = 1;      /* this thread */
 406                 svc_next_pending = svc_last_pending = 0;
 407
 408                 /*
 409                  * Create a pipe for waking up the poll, if new
 410                  * descriptors have been added to svc_fdset.
 411                  */
 412                 create_pipe();
 413         }
 414
 415         /* OTHER THREADS ARE RUNNING */
 416
 417         if (svc_exit_done)
 418                 return;
 419
 420         for (;;) {
 421                 /*
 422                  * svc_thr_mutex prevents more than one thread from
 423                  * trying to select a descriptor to process further.
 424                  * svc_thr_mutex is unlocked after a thread selects
 425                  * a descriptor on which to receive data.  If there are
 426                  * no such descriptors, the thread will poll with
 427                  * svc_thr_mutex locked, after unlocking all other
 428                  * locks.  This prevents more than one thread from
 429                  * trying to poll at the same time.
 430                  */
 431                 (void) mutex_lock(&svc_thr_mutex);
 432                 (void) mutex_lock(&svc_mutex);
 433 continue_with_locks:
 434                 myfd = -1;
 435                 mypollfd = INVALID_POLLFD;
 436
 437                 /*
 438                  * Check if there are any descriptors with data pending.
 439                  */
 440                 if (svc_total_pending > 0) {
 441                         myfd = svc_pending_fds[svc_next_pending++];
 442                         mypollfd = FD_FROM_PENDING;
 443                         if (svc_next_pending > CIRCULAR_BUFSIZE)
 444                                 svc_next_pending = 0;
 445                         svc_total_pending--;
 446                 }
 447
 448                 /*
 449                  * Get the next active file descriptor to process.
 450                  */
 451                 if (myfd == -1 && svc_pollfds == 0) {
 452                         /*
 453                          * svc_pollset is empty; do polling
 454                          */
 455                         svc_polling = TRUE;
 456
 457                         /*
 458                          * if there are no file descriptors, return
 459                          */
 460                         (void) rw_rdlock(&svc_fd_lock);
 461                         if (svc_npollfds == 0 ||
 462                             alloc_pollset(svc_npollfds + 1) == -1) {
 463                                 (void) rw_unlock(&svc_fd_lock);
 464                                 svc_polling = FALSE;
 465                                 svc_thr_total--;
 466                                 (void) mutex_unlock(&svc_mutex);
 467                                 (void) mutex_unlock(&svc_thr_mutex);
 468                                 if (!main_thread) {
 469                                         thr_exit(NULL);
 470                                         /* NOTREACHED */
 471                                 }
 472                                 break;
 473                         }
 474
 475                         npollfds = __rpc_compress_pollfd(svc_max_pollfd,
 476                             svc_pollfd, svc_pollset);
 477                         (void) rw_unlock(&svc_fd_lock);
 478
 479                         if (npollfds == 0) {
 480                                 /*
 481                                  * There are file descriptors, but none of them
 482                                  * are available for polling.  If this is the
 483                                  * main thread, or if no thread is waiting,
 484                                  * wait on condition variable, otherwise exit.
 485                                  */
 486                                 svc_polling = FALSE;
 487                                 (void) mutex_unlock(&svc_thr_mutex);
 488                                 if ((!main_thread) && svc_waiters > 0) {
 489                                         svc_thr_total--;
 490                                         (void) mutex_unlock(&svc_mutex);
 491                                         thr_exit(NULL);
 492                                         /* NOTREACHED */
 493                                 }
 494
 495                                 while (svc_npollfds_set == 0 &&
 496                                     svc_pollfds == 0 &&
 497                                     svc_total_pending == 0 &&
 498                                     !svc_exit_done) {
 499                                         svc_waiters++;
 500                                         (void) cond_wait(&svc_thr_fdwait,
 501                                             &svc_mutex);
 502                                         svc_waiters--;
 503                                 }
 504
 505                                 /*
 506                                  * Check exit flag.  If this is not the main
 507                                  * thread, exit.
 508                                  */
 509                                 if (svc_exit_done) {
 510                                         svc_thr_total--;
 511                                         (void) mutex_unlock(&svc_mutex);
 512                                         if (!main_thread)
 513                                                 thr_exit(NULL);
 514                                         break;
 515                                 }
 516
 517                                 (void) mutex_unlock(&svc_mutex);
 518                                 continue;
 519                         }
 520
 521                         /*
 522                          * We're ready to poll.  Always set svc_pipe[0]
 523                          * as the last one, since the poll will occasionally
 524                          * need to be interrupted.  Release svc_mutex for
 525                          * the duration of the poll, but hold on to
 526                          * svc_thr_mutex, as we don't want any other thread
 527                          * to do the same.
 528                          */
 529                         svc_pollset[npollfds].fd = svc_pipe[0];
 530                         svc_pollset[npollfds].events = MASKVAL;
 531
 532                         do {
 533                                 int i, j;
 534
 535                                 (void) mutex_unlock(&svc_mutex);
 536                                 n_polled = poll(svc_pollset, npollfds + 1, -1);
 537                                 (void) mutex_lock(&svc_mutex);
 538                                 if (n_polled <= 0)
 539                                         continue;
 540
 541                                 /*
 542                                  * Check if information returned indicates one
 543                                  * or more closed fd's; find and remove any such
 544                                  * information
 545                                  */
 546                                 for (i = 0; i <= npollfds; i++) {
 547                                         if (svc_pollset[i].revents & POLLNVAL) {
 548                                                 /* Overwrite svc_pollset[i] */
 549                                                 for (j = i; j < npollfds; j++)
 550                                                         svc_pollset[j] =
 551                                                             svc_pollset[j + 1];
 552                                                 (void) memset(&svc_pollset[j],
 553                                                     0, sizeof (struct pollfd));
 554                                                 npollfds--;
 555                                                 n_polled--;
 556                                                 i--;
 557                                         }
 558                                 }
 559                         } while (n_polled <= 0);
 560                         svc_polling = FALSE;
 561
 562                         /*
 563                          * If there's data in the pipe, clear it.
 564                          */
 565                         if (svc_pollset[npollfds].revents) {
 566                                 clear_pipe();
 567                                 n_polled--;
 568                                 svc_pollset[npollfds].revents = 0;
 569                         }
 570                         svc_polled = npollfds;
 571                         svc_pollfds = n_polled;
 572                         svc_next_pollfd = 0;
 573
 574                         /*
 575                          * Check exit flag.
 576                          */
 577                         if (svc_exit_done) {
 578                                 svc_thr_total--;
 579                                 (void) mutex_unlock(&svc_mutex);
 580                                 (void) mutex_unlock(&svc_thr_mutex);
 581                                 if (!main_thread) {
 582                                         thr_exit(NULL);
 583                                         /* NOTREACHED */
 584                                 }
 585                                 break;
 586                         }
 587
 588                         /*
 589                          * If no descriptor is active, continue.
 590                          */
 591                         if (svc_pollfds == 0)
 592                                 goto continue_with_locks;
 593                 }
 594
 595                 /*
 596                  * If a file descriptor has already not been selected,
 597                  * choose a file descriptor.
 598                  * svc_pollfds and svc_next_pollfd are updated.
 599                  */
 600                 if (myfd == -1) {
 601                         if (select_next_pollfd(&myfd, &mypollfd) == -1)
 602                                 goto continue_with_locks;
 603                 }
 604
 605                 /*
 606                  * Check to see if new threads need to be started.
 607                  * Count of threads that could be gainfully employed is
 608                  * obtained as follows:
 609                  *      - count 1 for poller
 610                  *      - count 1 for this request
 611                  *      - count active file descriptors (svc_pollfds)
 612                  *      - count pending file descriptors
 613                  *
 614                  * (svc_thr_total - svc_thr_active) are already available.
 615                  * This thread is one of the available threads.
 616                  *
 617                  * Number of new threads should not exceed
 618                  *      (svc_thr_max - svc_thr_total).
 619                  */
 620                 if (svc_thr_total < svc_thr_max &&
 621                     svc_mt_mode == RPC_SVC_MT_AUTO && !svc_exit_done) {
 622                         n_new = 1 + 1 + svc_pollfds + svc_total_pending -
 623                             (svc_thr_total - svc_thr_active);
 624                         if (n_new > (svc_thr_max - svc_thr_total))
 625                                 n_new = svc_thr_max - svc_thr_total;
 626                         if (n_new > 0)
 627                                 start_threads(n_new);
 628                 }
 629
 630                 /*
 631                  * Get parent xprt.  It is possible for the parent service
 632                  * handle to be destroyed by now, due to a race condition.
 633                  * Check for this, and if so, log a warning and go on.
 634                  */
 635                 parent_xprt = svc_xports[myfd];
 636                 if (parent_xprt == NULL) {
 637                         /* Check if it is not a user FD */
 638                         if (__is_a_userfd(myfd) == TRUE)
 639                                 __svc_getreq_user(&(svc_pollset[mypollfd]));
 640                         goto continue_with_locks;
 641                 }
 642 /* LINTED pointer alignment */
 643                 if (svc_defunct(parent_xprt) || svc_failed(parent_xprt))
 644                         goto continue_with_locks;
 645
 646                 /*
 647                  * Make a copy of parent xprt, update svc_fdset.
 648                  */
 649                 if ((xprt = make_xprt_copy(parent_xprt)) == NULL)
 650                         goto continue_with_locks;
 651
 652                 /*
 653                  * Keep track of active threads in automatic mode.
 654                  */
 655                 if (svc_mt_mode == RPC_SVC_MT_AUTO)
 656                         svc_thr_active++;
 657
 658                 /*
 659                  * Release mutexes so other threads can get going.
 660                  */
 661                 (void) mutex_unlock(&svc_mutex);
 662                 (void) mutex_unlock(&svc_thr_mutex);
 663
 664                 /*
 665                  * Process request.
 666                  */
 667                 {
 668                         struct rpc_msg *msg;
 669                         struct svc_req *r;
 670                         char *cred_area;
 671
 672 /* LINTED pointer alignment */
 673                         msg = SVCEXT(xprt)->msg;
 674 /* LINTED pointer alignment */
 675                         r = SVCEXT(xprt)->req;
 676 /* LINTED pointer alignment */
 677                         cred_area = SVCEXT(xprt)->cred_area;
 678
 679
 680                         msg->rm_call.cb_cred.oa_base = cred_area;
 681                         msg->rm_call.cb_verf.oa_base =
 682                             &(cred_area[MAX_AUTH_BYTES]);
 683                         r->rq_clntcred = &(cred_area[2 * MAX_AUTH_BYTES]);
 684
 685                         /*
 686                          * receive RPC message
 687                          */
 688                         if ((dispatch = SVC_RECV(xprt, msg))) {
 689                                 if (svc_mt_mode != RPC_SVC_MT_NONE)
 690 /* LINTED pointer alignment */
 691                                         svc_flags(xprt) |= SVC_ARGS_CHECK;
 692                                 dispatch = _svc_prog_dispatch(xprt, msg, r);
 693
 694                                 /*
 695                                  * Call cleanup procedure if set.
 696                                  */
 697                                 if (__proc_cleanup_cb != NULL)
 698                                         (*__proc_cleanup_cb)(xprt);
 699                         } else
 700                                 svc_args_done(xprt);
 701
 702                         /*
 703                          * Finish up, if automatic mode, or not dispatched.
 704                          */
 705                         if (svc_mt_mode == RPC_SVC_MT_AUTO || !dispatch) {
 706 /* LINTED pointer alignment */
 707                                 if (svc_flags(xprt) & SVC_ARGS_CHECK)
 708                                         svc_args_done(xprt);
 709                                 (void) mutex_lock(&svc_mutex);
 710                                 _svc_done_private(xprt);
 711                                 if (svc_mt_mode == RPC_SVC_MT_AUTO) {
 712                                         /*
 713                                          * not active any more
 714                                          */
 715                                         svc_thr_active--;
 716
 717                                         /*
 718                                          * If not main thread, exit unless
 719                                          * there's some immediate work.
 720                                          */
 721                                         if (!main_thread &&
 722                                             svc_pollfds <= 0 &&
 723                                             svc_total_pending <= 0 &&
 724                                             (svc_polling ||
 725                                             svc_waiters > 0)) {
 726                                                 svc_thr_total--;
 727                                                 if (svc_thr_total ==
 728                                                     svc_waiters) {
 729                                                         (void) cond_broadcast(
 730                                                             &svc_thr_fdwait);
 731                                                 }
 732                                                 (void) mutex_unlock(&svc_mutex);
 733                                                 thr_exit(NULL);
 734                                                 /* NOTREACHED */
 735                                         }
 736                                 }
 737                                 (void) mutex_unlock(&svc_mutex);
 738                         }
 739                 }
 740
 741         }
 742 }
 743
 744
 745 /*
 746  * start_threads() - Start specified number of threads.
 747  */
 748 static void
 749 start_threads(int num_threads)
 750 {
 751         int             i;
 752
 753         assert(MUTEX_HELD(&svc_mutex));
 754
 755         for (i = 0; i < num_threads; i++) {
 756                 if (thr_create(NULL, 0, (void *(*)(void *))_svc_run_mt, NULL,
 757                     THR_DETACHED, NULL) == 0) {
 758                         svc_thr_total++;
 759                         svc_thr_total_creates++;
 760                 } else {
 761                         svc_thr_total_create_errors++;
 762                 }
 763         }
 764 }
 765
 766
 767 /*
 768  * create_pipe() - create pipe for breaking out of poll.
 769  */
 770 static void
 771 create_pipe(void)
 772 {
 773         if (pipe(svc_pipe) == -1) {
 774                 syslog(LOG_ERR, dgettext(__nsl_dom,
 775                     "RPC: svc could not create pipe - exiting"));
 776                 exit(1);
 777         }
 778         if (fcntl(svc_pipe[0], F_SETFL, O_NONBLOCK) == -1) {
 779                 syslog(LOG_ERR, dgettext(__nsl_dom,
 780                     "RPC: svc pipe error - exiting"));
 781                 exit(1);
 782         }
 783         if (fcntl(svc_pipe[1], F_SETFL, O_NONBLOCK) == -1) {
 784                 syslog(LOG_ERR, dgettext(__nsl_dom,
 785                     "RPC: svc pipe error - exiting"));
 786                 exit(1);
 787         }
 788 }
 789
 790
 791 /*
 792  * clear_pipe() - Empty data in pipe.
 793  */
 794 static void
 795 clear_pipe(void)
 796 {
 797         char    buf[16];
 798         int     i;
 799
 800         do {
 801                 i = read(svc_pipe[0], buf, sizeof (buf));
 802         } while (i == sizeof (buf));
 803 }
 804
 805
 806 /*
 807  * select_next_pollfd() - Select the next active fd in svc_pollset.
 808  */
 809 static int
 810 select_next_pollfd(int *fd, int *pollfdIndex)
 811 {
 812         int i;
 813
 814         assert(MUTEX_HELD(&svc_thr_mutex));
 815         assert(MUTEX_HELD(&svc_mutex));
 816
 817         for (i = svc_next_pollfd; svc_pollfds > 0 && i < svc_polled; i++) {
 818                 if (svc_pollset[i].revents) {
 819                         svc_pollfds--;
 820                         /*
 821                          * No more special case for POLLNVAL, because it may
 822                          * be linked with a user file descriptot callback
 823                          */
 824                         svc_next_pollfd = i + 1;
 825
 826                         *fd = svc_pollset[i].fd;
 827                         *pollfdIndex = i;
 828
 829                         return (0);
 830                 }
 831         }
 832         svc_next_pollfd = svc_pollfds = 0;
 833         *fd = -1;
 834         *pollfdIndex = INVALID_POLLFD;
 835         return (-1);
 836 }
 837
 838
 839 /*
 840  * make_xprt_copy() - make a copy of the parent xprt.
 841  * Clear fd bit in svc_fdset.
 842  */
 843 static SVCXPRT *
 844 make_xprt_copy(SVCXPRT *parent)
 845 {
 846 /* LINTED pointer alignment */
 847         SVCXPRT_LIST    *xlist = SVCEXT(parent)->my_xlist;
 848         SVCXPRT_LIST    *xret;
 849         SVCXPRT         *xprt;
 850         int             fd = parent->xp_fd;
 851
 852         assert(MUTEX_HELD(&svc_mutex));
 853
 854         xret = xlist->next;
 855         if (xret) {
 856                 xlist->next = xret->next;
 857                 xret->next = NULL;
 858                 xprt = xret->xprt;
 859 /* LINTED pointer alignment */
 860                 svc_flags(xprt) = svc_flags(parent);
 861         } else
 862                 xprt = svc_copy(parent);
 863
 864         if (xprt) {
 865 /* LINTED pointer alignment */
 866                 SVCEXT(parent)->refcnt++;
 867                 (void) rw_wrlock(&svc_fd_lock);
 868                 clear_pollfd(fd);
 869                 (void) rw_unlock(&svc_fd_lock);
 870         }
 871         return (xprt);
 872 }
 873
 874 /*
 875  * _svc_done_private() - return copies to library.
 876  */
 877 static void
 878 _svc_done_private(SVCXPRT *xprt)
 879 {
 880         SVCXPRT         *parent;
 881         SVCXPRT_LIST    *xhead, *xlist;
 882
 883         assert(MUTEX_HELD(&svc_mutex));
 884
 885 /* LINTED pointer alignment */
 886         if ((parent = SVCEXT(xprt)->parent) == NULL)
 887                 return;
 888
 889 /* LINTED pointer alignment */
 890         xhead = SVCEXT(parent)->my_xlist;
 891 /* LINTED pointer alignment */
 892         xlist = SVCEXT(xprt)->my_xlist;
 893         xlist->next = xhead->next;
 894         xhead->next = xlist;
 895
 896 /* LINTED pointer alignment */
 897         SVCEXT(parent)->refcnt--;
 898
 899         /*
 900          * Propagate any error flags.  This is done in both directions to
 901          * ensure that if one child gets an error, everyone will see it
 902          * (even if there are multiple outstanding children) and the
 903          * transport will get closed.
 904          */
 905 /* LINTED pointer alignment */
 906         svc_flags(xprt) |= svc_flags(parent);
 907 /* LINTED pointer alignment */
 908         if (svc_failed(xprt) || svc_defunct(xprt)) {
 909 /* LINTED pointer alignment */
 910                 svc_flags(parent) |= (svc_flags(xprt) &
 911                     (SVC_FAILED | SVC_DEFUNCT));
 912 /* LINTED pointer alignment */
 913                 if (SVCEXT(parent)->refcnt == 0)
 914                         _svc_destroy_private(xprt);
 915         }
 916 }
 917
 918 void
 919 svc_done(SVCXPRT *xprt)
 920 {
 921         if (svc_mt_mode != RPC_SVC_MT_USER)
 922                 return;
 923
 924         /*
 925          * Make sure file descriptor is released in user mode.
 926          * If the xprt is a door, do nothing: this work is performed by
 927          * svc_door.c's return_xprt_copy() routine, which is basically a
 928          * door-specific copy of _svc_done_private().
 929          */
 930 /* LINTED pointer alignment */
 931         if (svc_type(xprt) == SVC_DOOR)
 932                 return;
 933
 934 /* LINTED pointer alignment */
 935         if (svc_flags(xprt) & SVC_ARGS_CHECK)
 936                 svc_args_done(xprt);
 937
 938         (void) mutex_lock(&svc_mutex);
 939         _svc_done_private(xprt);
 940         (void) mutex_unlock(&svc_mutex);
 941 }
 942
 943
 944 /*
 945  * Mark argument completion.  Release file descriptor.
 946  */
 947 void
 948 svc_args_done(SVCXPRT *xprt)
 949 {
 950         char    dummy;
 951 /* LINTED pointer alignment */
 952         SVCXPRT *parent = SVCEXT(xprt)->parent;
 953         bool_t  wake_up_poller;
 954         enum    xprt_stat stat;
 955
 956 /* LINTED pointer alignment */
 957         svc_flags(xprt) |= svc_flags(parent);
 958 /* LINTED pointer alignment */
 959         svc_flags(xprt) &= ~SVC_ARGS_CHECK;
 960 /* LINTED pointer alignment */
 961         if (svc_failed(xprt) || svc_defunct(parent))
 962                 return;
 963
 964 /* LINTED pointer alignment */
 965         if (svc_type(xprt) == SVC_CONNECTION &&
 966             (stat = SVC_STAT(xprt)) != XPRT_IDLE) {
 967                 if (stat == XPRT_MOREREQS) {
 968                         (void) mutex_lock(&svc_mutex);
 969                         svc_pending_fds[svc_last_pending++] = xprt->xp_fd;
 970                         if (svc_last_pending > CIRCULAR_BUFSIZE)
 971                                 svc_last_pending = 0;
 972                         svc_total_pending++;
 973                         (void) mutex_unlock(&svc_mutex);
 974                         wake_up_poller = FALSE;
 975                 } else {
 976                         /*
 977                          * connection failed
 978                          */
 979                         return;
 980                 }
 981         } else {
 982                 (void) rw_wrlock(&svc_fd_lock);
 983                 set_pollfd(xprt->xp_fd, MASKVAL);
 984                 (void) rw_unlock(&svc_fd_lock);
 985                 wake_up_poller = TRUE;
 986         }
 987
 988         if (!wake_up_poller || !svc_polling) {
 989                 /*
 990                  * Wake up any waiting threads.
 991                  */
 992                 (void) mutex_lock(&svc_mutex);
 993                 if (svc_waiters > 0) {
 994                         (void) cond_broadcast(&svc_thr_fdwait);
 995                         (void) mutex_unlock(&svc_mutex);
 996                         return;
 997                 }
 998                 (void) mutex_unlock(&svc_mutex);
 999         }
1000
1001         /*
1002          * Wake up any polling thread.
1003          */
1004         if (svc_polling)
1005                 (void) write(svc_pipe[1], &dummy, sizeof (dummy));
1006 }
1007
1008
1009 int
1010 __rpc_legal_connmaxrec(int suggested) {
1011         if (suggested == -1) {
1012                 /* Supply default */
1013                 return (RPC_MAXDATASIZE + 2*sizeof (uint32_t));
1014         } else if (suggested < 0) {
1015                 return (-1);
1016         } else if (suggested > 0) {
1017                 /* Round down to multiple of BYTES_PER_XDR_UNIT */
1018                 suggested -= suggested % BYTES_PER_XDR_UNIT;
1019                 /* If possible, allow for two fragment headers */
1020                 if (suggested < MAXINT-(2*sizeof (uint32_t))) {
1021                         /* Allow for two fragment headers */
1022                         suggested += 2 * sizeof (uint32_t);
1023                 } else {
1024                         suggested = MAXINT;
1025                 }
1026                 if (suggested < sizeof (struct rpc_msg)) {
1027                         return (-1);
1028                 }
1029         }
1030         return (suggested);
1031 }
1032
1033
1034 bool_t
1035 rpc_control(int op, void *info)
1036 {
1037         int             tmp;
1038
1039         switch (op) {
1040         case RPC_SVC_MTMODE_SET:
1041                 tmp = *((int *)info);
1042                 if (tmp != RPC_SVC_MT_NONE && tmp != RPC_SVC_MT_AUTO &&
1043                     tmp != RPC_SVC_MT_USER)
1044                         return (FALSE);
1045                 if (svc_mt_mode != RPC_SVC_MT_NONE && svc_mt_mode != tmp)
1046                         return (FALSE);
1047                 svc_mt_mode = tmp;
1048                 return (TRUE);
1049         case RPC_SVC_MTMODE_GET:
1050                 *((int *)info) = svc_mt_mode;
1051                 return (TRUE);
1052         case RPC_SVC_THRMAX_SET:
1053                 if ((tmp = *((int *)info)) < 1)
1054                         return (FALSE);
1055                 (void) mutex_lock(&svc_mutex);
1056                 svc_thr_max = tmp;
1057                 (void) mutex_unlock(&svc_mutex);
1058                 return (TRUE);
1059         case RPC_SVC_THRMAX_GET:
1060                 *((int *)info) = svc_thr_max;
1061                 return (TRUE);
1062         case RPC_SVC_THRTOTAL_GET:
1063                 *((int *)info) = svc_thr_total;
1064                 return (TRUE);
1065         case RPC_SVC_THRCREATES_GET:
1066                 *((int *)info) = svc_thr_total_creates;
1067                 return (TRUE);
1068         case RPC_SVC_THRERRORS_GET:
1069                 *((int *)info) = svc_thr_total_create_errors;
1070                 return (TRUE);
1071         case RPC_SVC_USE_POLLFD:
1072                 if (*((int *)info) && !__rpc_use_pollfd_done) {
1073                         __rpc_use_pollfd_done = 1;
1074                         return (TRUE);
1075                 }
1076                 return (FALSE);
1077         case RPC_SVC_CONNMAXREC_SET:
1078                 tmp = __rpc_legal_connmaxrec(*(int *)info);
1079                 if (tmp >= 0) {
1080                         __rpc_connmaxrec = tmp;
1081                         return (TRUE);
1082                 } else {
1083                         return (FALSE);
1084                 }
1085         case RPC_SVC_CONNMAXREC_GET:
1086                 *((int *)info) = __rpc_connmaxrec;
1087                 return (TRUE);
1088         case RPC_SVC_IRTIMEOUT_SET:
1089                 tmp = *((int *)info);
1090                 if (tmp >= 0) {
1091                         __rpc_irtimeout = tmp;
1092                         return (TRUE);
1093                 } else {
1094                         return (FALSE);
1095                 }
1096         /*
1097          * No mutex necessary as _EXCLBIND_SET will/should only
1098          * be used before an RPC daemon goes mt-hot.
1099          */
1100         case __RPC_SVC_EXCLBIND_SET:
1101                 if (info) {
1102                         __rpc_tp_exclbind = *((bool_t *)info);
1103                         return (TRUE);
1104                 }
1105                 return (FALSE);
1106         case __RPC_SVC_EXCLBIND_GET:
1107                 if (info) {
1108                         *((bool_t *)info) = __rpc_tp_exclbind;
1109                         return (TRUE);
1110                 }
1111                 return (FALSE);
1112
1113         case __RPC_SVC_LSTNBKLOG_SET:
1114                 tmp = *(int *)info;
1115                 if (tmp > 0) {
1116                         __svc_lstnbklog = tmp;
1117                         return (TRUE);
1118                 }
1119                 return (FALSE);
1120         case __RPC_SVC_LSTNBKLOG_GET:
1121                 *(int *)info = __svc_lstnbklog;
1122                 return (TRUE);
1123
1124         default:
1125                 return (FALSE);
1126         }
1127 }