1 /*- 2 * Copyright (c) 2003, Jeffrey Roberson <jeff@freebsd.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice unmodified, this list of conditions, and the following 10 * disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include "opt_compat.h" 31 #include "opt_posix.h" 32 #include <sys/param.h> 33 #include <sys/kernel.h> 34 #include <sys/lock.h> 35 #include <sys/mutex.h> 36 #include <sys/priv.h> 37 #include <sys/proc.h> 38 #include <sys/posix4.h> 39 #include <sys/racct.h> 40 #include <sys/resourcevar.h> 41 #include <sys/rwlock.h> 42 #include <sys/sched.h> 43 #include <sys/sysctl.h> 44 #include <sys/smp.h> 45 #include <sys/syscallsubr.h> 46 #include <sys/sysent.h> 47 #include <sys/systm.h> 48 #include <sys/sysproto.h> 49 #include <sys/signalvar.h> 50 #include <sys/sysctl.h> 51 #include <sys/ucontext.h> 52 #include <sys/thr.h> 53 #include <sys/rtprio.h> 54 #include <sys/umtx.h> 55 #include <sys/limits.h> 56 57 #include <machine/frame.h> 58 59 #include <security/audit/audit.h> 60 61 static SYSCTL_NODE(_kern, OID_AUTO, threads, CTLFLAG_RW, 0, 62 "thread allocation"); 63 64 static int max_threads_per_proc = 1500; 65 SYSCTL_INT(_kern_threads, OID_AUTO, max_threads_per_proc, CTLFLAG_RW, 66 &max_threads_per_proc, 0, "Limit on threads per proc"); 67 68 static int max_threads_hits; 69 SYSCTL_INT(_kern_threads, OID_AUTO, max_threads_hits, CTLFLAG_RD, 70 &max_threads_hits, 0, "kern.threads.max_threads_per_proc hit count"); 71 72 #ifdef COMPAT_FREEBSD32 73 74 static inline int 75 suword_lwpid(void *addr, lwpid_t lwpid) 76 { 77 int error; 78 79 if (SV_CURPROC_FLAG(SV_LP64)) 80 error = suword(addr, lwpid); 81 else 82 error = suword32(addr, lwpid); 83 return (error); 84 } 85 86 #else 87 #define suword_lwpid suword 88 #endif 89 90 static int create_thread(struct thread *td, mcontext_t *ctx, 91 void (*start_func)(void *), void *arg, 92 char *stack_base, size_t stack_size, 93 char *tls_base, 94 long *child_tid, long *parent_tid, 95 int flags, struct rtprio *rtp); 96 97 /* 98 * System call interface. 99 */ 100 int 101 sys_thr_create(struct thread *td, struct thr_create_args *uap) 102 /* ucontext_t *ctx, long *id, int flags */ 103 { 104 ucontext_t ctx; 105 int error; 106 107 if ((error = copyin(uap->ctx, &ctx, sizeof(ctx)))) 108 return (error); 109 110 error = create_thread(td, &ctx.uc_mcontext, NULL, NULL, 111 NULL, 0, NULL, uap->id, NULL, uap->flags, NULL); 112 return (error); 113 } 114 115 int 116 sys_thr_new(struct thread *td, struct thr_new_args *uap) 117 /* struct thr_param * */ 118 { 119 struct thr_param param; 120 int error; 121 122 if (uap->param_size < 0 || uap->param_size > sizeof(param)) 123 return (EINVAL); 124 bzero(¶m, sizeof(param)); 125 if ((error = copyin(uap->param, ¶m, uap->param_size))) 126 return (error); 127 return (kern_thr_new(td, ¶m)); 128 } 129 130 int 131 kern_thr_new(struct thread *td, struct thr_param *param) 132 { 133 struct rtprio rtp, *rtpp; 134 int error; 135 136 rtpp = NULL; 137 if (param->rtp != 0) { 138 error = copyin(param->rtp, &rtp, sizeof(struct rtprio)); 139 if (error) 140 return (error); 141 rtpp = &rtp; 142 } 143 error = create_thread(td, NULL, param->start_func, param->arg, 144 param->stack_base, param->stack_size, param->tls_base, 145 param->child_tid, param->parent_tid, param->flags, 146 rtpp); 147 return (error); 148 } 149 150 static int 151 create_thread(struct thread *td, mcontext_t *ctx, 152 void (*start_func)(void *), void *arg, 153 char *stack_base, size_t stack_size, 154 char *tls_base, 155 long *child_tid, long *parent_tid, 156 int flags, struct rtprio *rtp) 157 { 158 stack_t stack; 159 struct thread *newtd; 160 struct proc *p; 161 int error; 162 163 p = td->td_proc; 164 165 /* Have race condition but it is cheap. */ 166 if (p->p_numthreads >= max_threads_per_proc) { 167 ++max_threads_hits; 168 return (EPROCLIM); 169 } 170 171 if (rtp != NULL) { 172 switch(rtp->type) { 173 case RTP_PRIO_REALTIME: 174 case RTP_PRIO_FIFO: 175 /* Only root can set scheduler policy */ 176 if (priv_check(td, PRIV_SCHED_SETPOLICY) != 0) 177 return (EPERM); 178 if (rtp->prio > RTP_PRIO_MAX) 179 return (EINVAL); 180 break; 181 case RTP_PRIO_NORMAL: 182 rtp->prio = 0; 183 break; 184 default: 185 return (EINVAL); 186 } 187 } 188 189 #ifdef RACCT 190 if (racct_enable) { 191 PROC_LOCK(p); 192 error = racct_add(p, RACCT_NTHR, 1); 193 PROC_UNLOCK(p); 194 if (error != 0) 195 return (EPROCLIM); 196 } 197 #endif 198 199 /* Initialize our td */ 200 newtd = thread_alloc(0); 201 if (newtd == NULL) { 202 error = ENOMEM; 203 goto fail; 204 } 205 206 cpu_set_upcall(newtd, td); 207 208 /* 209 * Try the copyout as soon as we allocate the td so we don't 210 * have to tear things down in a failure case below. 211 * Here we copy out tid to two places, one for child and one 212 * for parent, because pthread can create a detached thread, 213 * if parent wants to safely access child tid, it has to provide 214 * its storage, because child thread may exit quickly and 215 * memory is freed before parent thread can access it. 216 */ 217 if ((child_tid != NULL && 218 suword_lwpid(child_tid, newtd->td_tid)) || 219 (parent_tid != NULL && 220 suword_lwpid(parent_tid, newtd->td_tid))) { 221 thread_free(newtd); 222 error = EFAULT; 223 goto fail; 224 } 225 226 bzero(&newtd->td_startzero, 227 __rangeof(struct thread, td_startzero, td_endzero)); 228 bcopy(&td->td_startcopy, &newtd->td_startcopy, 229 __rangeof(struct thread, td_startcopy, td_endcopy)); 230 newtd->td_proc = td->td_proc; 231 newtd->td_ucred = crhold(td->td_ucred); 232 233 if (ctx != NULL) { /* old way to set user context */ 234 error = set_mcontext(newtd, ctx); 235 if (error != 0) { 236 thread_free(newtd); 237 crfree(td->td_ucred); 238 goto fail; 239 } 240 } else { 241 /* Set up our machine context. */ 242 stack.ss_sp = stack_base; 243 stack.ss_size = stack_size; 244 /* Set upcall address to user thread entry function. */ 245 cpu_set_upcall_kse(newtd, start_func, arg, &stack); 246 /* Setup user TLS address and TLS pointer register. */ 247 error = cpu_set_user_tls(newtd, tls_base); 248 if (error != 0) { 249 thread_free(newtd); 250 crfree(td->td_ucred); 251 goto fail; 252 } 253 } 254 255 PROC_LOCK(p); 256 p->p_flag |= P_HADTHREADS; 257 thread_link(newtd, p); 258 bcopy(p->p_comm, newtd->td_name, sizeof(newtd->td_name)); 259 thread_lock(td); 260 /* let the scheduler know about these things. */ 261 sched_fork_thread(td, newtd); 262 thread_unlock(td); 263 if (P_SHOULDSTOP(p)) 264 newtd->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK; 265 PROC_UNLOCK(p); 266 267 tidhash_add(newtd); 268 269 thread_lock(newtd); 270 if (rtp != NULL) { 271 if (!(td->td_pri_class == PRI_TIMESHARE && 272 rtp->type == RTP_PRIO_NORMAL)) { 273 rtp_to_pri(rtp, newtd); 274 sched_prio(newtd, newtd->td_user_pri); 275 } /* ignore timesharing class */ 276 } 277 TD_SET_CAN_RUN(newtd); 278 sched_add(newtd, SRQ_BORING); 279 thread_unlock(newtd); 280 281 return (0); 282 283 fail: 284 #ifdef RACCT 285 if (racct_enable) { 286 PROC_LOCK(p); 287 racct_sub(p, RACCT_NTHR, 1); 288 PROC_UNLOCK(p); 289 } 290 #endif 291 return (error); 292 } 293 294 int 295 sys_thr_self(struct thread *td, struct thr_self_args *uap) 296 /* long *id */ 297 { 298 int error; 299 300 error = suword_lwpid(uap->id, (unsigned)td->td_tid); 301 if (error == -1) 302 return (EFAULT); 303 return (0); 304 } 305 306 int 307 sys_thr_exit(struct thread *td, struct thr_exit_args *uap) 308 /* long *state */ 309 { 310 struct proc *p; 311 312 p = td->td_proc; 313 314 /* Signal userland that it can free the stack. */ 315 if ((void *)uap->state != NULL) { 316 suword_lwpid(uap->state, 1); 317 kern_umtx_wake(td, uap->state, INT_MAX, 0); 318 } 319 320 rw_wlock(&tidhash_lock); 321 322 PROC_LOCK(p); 323 324 if (p->p_numthreads != 1) { 325 racct_sub(p, RACCT_NTHR, 1); 326 LIST_REMOVE(td, td_hash); 327 rw_wunlock(&tidhash_lock); 328 tdsigcleanup(td); 329 umtx_thread_exit(td); 330 PROC_SLOCK(p); 331 thread_stopped(p); 332 thread_exit(); 333 /* NOTREACHED */ 334 } 335 336 /* 337 * Ignore attempts to shut down last thread in the proc. This 338 * will actually call _exit(2) in the usermode trampoline when 339 * it returns. 340 */ 341 PROC_UNLOCK(p); 342 rw_wunlock(&tidhash_lock); 343 return (0); 344 } 345 346 int 347 sys_thr_kill(struct thread *td, struct thr_kill_args *uap) 348 /* long id, int sig */ 349 { 350 ksiginfo_t ksi; 351 struct thread *ttd; 352 struct proc *p; 353 int error; 354 355 p = td->td_proc; 356 ksiginfo_init(&ksi); 357 ksi.ksi_signo = uap->sig; 358 ksi.ksi_code = SI_LWP; 359 ksi.ksi_pid = p->p_pid; 360 ksi.ksi_uid = td->td_ucred->cr_ruid; 361 if (uap->id == -1) { 362 if (uap->sig != 0 && !_SIG_VALID(uap->sig)) { 363 error = EINVAL; 364 } else { 365 error = ESRCH; 366 PROC_LOCK(p); 367 FOREACH_THREAD_IN_PROC(p, ttd) { 368 if (ttd != td) { 369 error = 0; 370 if (uap->sig == 0) 371 break; 372 tdksignal(ttd, uap->sig, &ksi); 373 } 374 } 375 PROC_UNLOCK(p); 376 } 377 } else { 378 error = 0; 379 ttd = tdfind((lwpid_t)uap->id, p->p_pid); 380 if (ttd == NULL) 381 return (ESRCH); 382 if (uap->sig == 0) 383 ; 384 else if (!_SIG_VALID(uap->sig)) 385 error = EINVAL; 386 else 387 tdksignal(ttd, uap->sig, &ksi); 388 PROC_UNLOCK(ttd->td_proc); 389 } 390 return (error); 391 } 392 393 int 394 sys_thr_kill2(struct thread *td, struct thr_kill2_args *uap) 395 /* pid_t pid, long id, int sig */ 396 { 397 ksiginfo_t ksi; 398 struct thread *ttd; 399 struct proc *p; 400 int error; 401 402 AUDIT_ARG_SIGNUM(uap->sig); 403 404 ksiginfo_init(&ksi); 405 ksi.ksi_signo = uap->sig; 406 ksi.ksi_code = SI_LWP; 407 ksi.ksi_pid = td->td_proc->p_pid; 408 ksi.ksi_uid = td->td_ucred->cr_ruid; 409 if (uap->id == -1) { 410 if ((p = pfind(uap->pid)) == NULL) 411 return (ESRCH); 412 AUDIT_ARG_PROCESS(p); 413 error = p_cansignal(td, p, uap->sig); 414 if (error) { 415 PROC_UNLOCK(p); 416 return (error); 417 } 418 if (uap->sig != 0 && !_SIG_VALID(uap->sig)) { 419 error = EINVAL; 420 } else { 421 error = ESRCH; 422 FOREACH_THREAD_IN_PROC(p, ttd) { 423 if (ttd != td) { 424 error = 0; 425 if (uap->sig == 0) 426 break; 427 tdksignal(ttd, uap->sig, &ksi); 428 } 429 } 430 } 431 PROC_UNLOCK(p); 432 } else { 433 ttd = tdfind((lwpid_t)uap->id, uap->pid); 434 if (ttd == NULL) 435 return (ESRCH); 436 p = ttd->td_proc; 437 AUDIT_ARG_PROCESS(p); 438 error = p_cansignal(td, p, uap->sig); 439 if (uap->sig == 0) 440 ; 441 else if (!_SIG_VALID(uap->sig)) 442 error = EINVAL; 443 else 444 tdksignal(ttd, uap->sig, &ksi); 445 PROC_UNLOCK(p); 446 } 447 return (error); 448 } 449 450 int 451 sys_thr_suspend(struct thread *td, struct thr_suspend_args *uap) 452 /* const struct timespec *timeout */ 453 { 454 struct timespec ts, *tsp; 455 int error; 456 457 tsp = NULL; 458 if (uap->timeout != NULL) { 459 error = umtx_copyin_timeout(uap->timeout, &ts); 460 if (error != 0) 461 return (error); 462 tsp = &ts; 463 } 464 465 return (kern_thr_suspend(td, tsp)); 466 } 467 468 int 469 kern_thr_suspend(struct thread *td, struct timespec *tsp) 470 { 471 struct proc *p = td->td_proc; 472 struct timeval tv; 473 int error = 0; 474 int timo = 0; 475 476 if (td->td_pflags & TDP_WAKEUP) { 477 td->td_pflags &= ~TDP_WAKEUP; 478 return (0); 479 } 480 481 if (tsp != NULL) { 482 if (tsp->tv_sec == 0 && tsp->tv_nsec == 0) 483 error = EWOULDBLOCK; 484 else { 485 TIMESPEC_TO_TIMEVAL(&tv, tsp); 486 timo = tvtohz(&tv); 487 } 488 } 489 490 PROC_LOCK(p); 491 if (error == 0 && (td->td_flags & TDF_THRWAKEUP) == 0) 492 error = msleep((void *)td, &p->p_mtx, 493 PCATCH, "lthr", timo); 494 495 if (td->td_flags & TDF_THRWAKEUP) { 496 thread_lock(td); 497 td->td_flags &= ~TDF_THRWAKEUP; 498 thread_unlock(td); 499 PROC_UNLOCK(p); 500 return (0); 501 } 502 PROC_UNLOCK(p); 503 if (error == EWOULDBLOCK) 504 error = ETIMEDOUT; 505 else if (error == ERESTART) { 506 if (timo != 0) 507 error = EINTR; 508 } 509 return (error); 510 } 511 512 int 513 sys_thr_wake(struct thread *td, struct thr_wake_args *uap) 514 /* long id */ 515 { 516 struct proc *p; 517 struct thread *ttd; 518 519 if (uap->id == td->td_tid) { 520 td->td_pflags |= TDP_WAKEUP; 521 return (0); 522 } 523 524 p = td->td_proc; 525 ttd = tdfind((lwpid_t)uap->id, p->p_pid); 526 if (ttd == NULL) 527 return (ESRCH); 528 thread_lock(ttd); 529 ttd->td_flags |= TDF_THRWAKEUP; 530 thread_unlock(ttd); 531 wakeup((void *)ttd); 532 PROC_UNLOCK(p); 533 return (0); 534 } 535 536 int 537 sys_thr_set_name(struct thread *td, struct thr_set_name_args *uap) 538 { 539 struct proc *p; 540 char name[MAXCOMLEN + 1]; 541 struct thread *ttd; 542 int error; 543 544 error = 0; 545 name[0] = '\0'; 546 if (uap->name != NULL) { 547 error = copyinstr(uap->name, name, sizeof(name), 548 NULL); 549 if (error) 550 return (error); 551 } 552 p = td->td_proc; 553 ttd = tdfind((lwpid_t)uap->id, p->p_pid); 554 if (ttd == NULL) 555 return (ESRCH); 556 strcpy(ttd->td_name, name); 557 #ifdef KTR 558 sched_clear_tdname(ttd); 559 #endif 560 PROC_UNLOCK(p); 561 return (error); 562 } 563