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 PROC_LOCK(td->td_proc); 191 error = racct_add(p, RACCT_NTHR, 1); 192 PROC_UNLOCK(td->td_proc); 193 if (error != 0) 194 return (EPROCLIM); 195 #endif 196 197 /* Initialize our td */ 198 newtd = thread_alloc(0); 199 if (newtd == NULL) { 200 error = ENOMEM; 201 goto fail; 202 } 203 204 cpu_set_upcall(newtd, td); 205 206 /* 207 * Try the copyout as soon as we allocate the td so we don't 208 * have to tear things down in a failure case below. 209 * Here we copy out tid to two places, one for child and one 210 * for parent, because pthread can create a detached thread, 211 * if parent wants to safely access child tid, it has to provide 212 * its storage, because child thread may exit quickly and 213 * memory is freed before parent thread can access it. 214 */ 215 if ((child_tid != NULL && 216 suword_lwpid(child_tid, newtd->td_tid)) || 217 (parent_tid != NULL && 218 suword_lwpid(parent_tid, newtd->td_tid))) { 219 thread_free(newtd); 220 error = EFAULT; 221 goto fail; 222 } 223 224 bzero(&newtd->td_startzero, 225 __rangeof(struct thread, td_startzero, td_endzero)); 226 bcopy(&td->td_startcopy, &newtd->td_startcopy, 227 __rangeof(struct thread, td_startcopy, td_endcopy)); 228 newtd->td_proc = td->td_proc; 229 newtd->td_ucred = crhold(td->td_ucred); 230 231 if (ctx != NULL) { /* old way to set user context */ 232 error = set_mcontext(newtd, ctx); 233 if (error != 0) { 234 thread_free(newtd); 235 crfree(td->td_ucred); 236 goto fail; 237 } 238 } else { 239 /* Set up our machine context. */ 240 stack.ss_sp = stack_base; 241 stack.ss_size = stack_size; 242 /* Set upcall address to user thread entry function. */ 243 cpu_set_upcall_kse(newtd, start_func, arg, &stack); 244 /* Setup user TLS address and TLS pointer register. */ 245 error = cpu_set_user_tls(newtd, tls_base); 246 if (error != 0) { 247 thread_free(newtd); 248 crfree(td->td_ucred); 249 goto fail; 250 } 251 } 252 253 PROC_LOCK(td->td_proc); 254 td->td_proc->p_flag |= P_HADTHREADS; 255 newtd->td_sigmask = td->td_sigmask; 256 thread_link(newtd, p); 257 bcopy(p->p_comm, newtd->td_name, sizeof(newtd->td_name)); 258 thread_lock(td); 259 /* let the scheduler know about these things. */ 260 sched_fork_thread(td, newtd); 261 thread_unlock(td); 262 if (P_SHOULDSTOP(p)) 263 newtd->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK; 264 PROC_UNLOCK(p); 265 266 tidhash_add(newtd); 267 268 thread_lock(newtd); 269 if (rtp != NULL) { 270 if (!(td->td_pri_class == PRI_TIMESHARE && 271 rtp->type == RTP_PRIO_NORMAL)) { 272 rtp_to_pri(rtp, newtd); 273 sched_prio(newtd, newtd->td_user_pri); 274 } /* ignore timesharing class */ 275 } 276 TD_SET_CAN_RUN(newtd); 277 sched_add(newtd, SRQ_BORING); 278 thread_unlock(newtd); 279 280 return (0); 281 282 fail: 283 #ifdef RACCT 284 PROC_LOCK(p); 285 racct_sub(p, RACCT_NTHR, 1); 286 PROC_UNLOCK(p); 287 #endif 288 return (error); 289 } 290 291 int 292 sys_thr_self(struct thread *td, struct thr_self_args *uap) 293 /* long *id */ 294 { 295 int error; 296 297 error = suword_lwpid(uap->id, (unsigned)td->td_tid); 298 if (error == -1) 299 return (EFAULT); 300 return (0); 301 } 302 303 int 304 sys_thr_exit(struct thread *td, struct thr_exit_args *uap) 305 /* long *state */ 306 { 307 struct proc *p; 308 309 p = td->td_proc; 310 311 /* Signal userland that it can free the stack. */ 312 if ((void *)uap->state != NULL) { 313 suword_lwpid(uap->state, 1); 314 kern_umtx_wake(td, uap->state, INT_MAX, 0); 315 } 316 317 rw_wlock(&tidhash_lock); 318 319 PROC_LOCK(p); 320 racct_sub(p, RACCT_NTHR, 1); 321 322 /* 323 * Shutting down last thread in the proc. This will actually 324 * call exit() in the trampoline when it returns. 325 */ 326 if (p->p_numthreads != 1) { 327 LIST_REMOVE(td, td_hash); 328 rw_wunlock(&tidhash_lock); 329 tdsigcleanup(td); 330 PROC_SLOCK(p); 331 thread_stopped(p); 332 thread_exit(); 333 /* NOTREACHED */ 334 } 335 PROC_UNLOCK(p); 336 rw_wunlock(&tidhash_lock); 337 return (0); 338 } 339 340 int 341 sys_thr_kill(struct thread *td, struct thr_kill_args *uap) 342 /* long id, int sig */ 343 { 344 ksiginfo_t ksi; 345 struct thread *ttd; 346 struct proc *p; 347 int error; 348 349 p = td->td_proc; 350 ksiginfo_init(&ksi); 351 ksi.ksi_signo = uap->sig; 352 ksi.ksi_code = SI_LWP; 353 ksi.ksi_pid = p->p_pid; 354 ksi.ksi_uid = td->td_ucred->cr_ruid; 355 if (uap->id == -1) { 356 if (uap->sig != 0 && !_SIG_VALID(uap->sig)) { 357 error = EINVAL; 358 } else { 359 error = ESRCH; 360 PROC_LOCK(p); 361 FOREACH_THREAD_IN_PROC(p, ttd) { 362 if (ttd != td) { 363 error = 0; 364 if (uap->sig == 0) 365 break; 366 tdksignal(ttd, uap->sig, &ksi); 367 } 368 } 369 PROC_UNLOCK(p); 370 } 371 } else { 372 error = 0; 373 ttd = tdfind((lwpid_t)uap->id, p->p_pid); 374 if (ttd == NULL) 375 return (ESRCH); 376 if (uap->sig == 0) 377 ; 378 else if (!_SIG_VALID(uap->sig)) 379 error = EINVAL; 380 else 381 tdksignal(ttd, uap->sig, &ksi); 382 PROC_UNLOCK(ttd->td_proc); 383 } 384 return (error); 385 } 386 387 int 388 sys_thr_kill2(struct thread *td, struct thr_kill2_args *uap) 389 /* pid_t pid, long id, int sig */ 390 { 391 ksiginfo_t ksi; 392 struct thread *ttd; 393 struct proc *p; 394 int error; 395 396 AUDIT_ARG_SIGNUM(uap->sig); 397 398 ksiginfo_init(&ksi); 399 ksi.ksi_signo = uap->sig; 400 ksi.ksi_code = SI_LWP; 401 ksi.ksi_pid = td->td_proc->p_pid; 402 ksi.ksi_uid = td->td_ucred->cr_ruid; 403 if (uap->id == -1) { 404 if ((p = pfind(uap->pid)) == NULL) 405 return (ESRCH); 406 AUDIT_ARG_PROCESS(p); 407 error = p_cansignal(td, p, uap->sig); 408 if (error) { 409 PROC_UNLOCK(p); 410 return (error); 411 } 412 if (uap->sig != 0 && !_SIG_VALID(uap->sig)) { 413 error = EINVAL; 414 } else { 415 error = ESRCH; 416 FOREACH_THREAD_IN_PROC(p, ttd) { 417 if (ttd != td) { 418 error = 0; 419 if (uap->sig == 0) 420 break; 421 tdksignal(ttd, uap->sig, &ksi); 422 } 423 } 424 } 425 PROC_UNLOCK(p); 426 } else { 427 ttd = tdfind((lwpid_t)uap->id, uap->pid); 428 if (ttd == NULL) 429 return (ESRCH); 430 p = ttd->td_proc; 431 AUDIT_ARG_PROCESS(p); 432 error = p_cansignal(td, p, uap->sig); 433 if (uap->sig == 0) 434 ; 435 else if (!_SIG_VALID(uap->sig)) 436 error = EINVAL; 437 else 438 tdksignal(ttd, uap->sig, &ksi); 439 PROC_UNLOCK(p); 440 } 441 return (error); 442 } 443 444 int 445 sys_thr_suspend(struct thread *td, struct thr_suspend_args *uap) 446 /* const struct timespec *timeout */ 447 { 448 struct timespec ts, *tsp; 449 int error; 450 451 tsp = NULL; 452 if (uap->timeout != NULL) { 453 error = umtx_copyin_timeout(uap->timeout, &ts); 454 if (error != 0) 455 return (error); 456 tsp = &ts; 457 } 458 459 return (kern_thr_suspend(td, tsp)); 460 } 461 462 int 463 kern_thr_suspend(struct thread *td, struct timespec *tsp) 464 { 465 struct proc *p = td->td_proc; 466 struct timeval tv; 467 int error = 0; 468 int timo = 0; 469 470 if (td->td_pflags & TDP_WAKEUP) { 471 td->td_pflags &= ~TDP_WAKEUP; 472 return (0); 473 } 474 475 if (tsp != NULL) { 476 if (tsp->tv_sec == 0 && tsp->tv_nsec == 0) 477 error = EWOULDBLOCK; 478 else { 479 TIMESPEC_TO_TIMEVAL(&tv, tsp); 480 timo = tvtohz(&tv); 481 } 482 } 483 484 PROC_LOCK(p); 485 if (error == 0 && (td->td_flags & TDF_THRWAKEUP) == 0) 486 error = msleep((void *)td, &p->p_mtx, 487 PCATCH, "lthr", timo); 488 489 if (td->td_flags & TDF_THRWAKEUP) { 490 thread_lock(td); 491 td->td_flags &= ~TDF_THRWAKEUP; 492 thread_unlock(td); 493 PROC_UNLOCK(p); 494 return (0); 495 } 496 PROC_UNLOCK(p); 497 if (error == EWOULDBLOCK) 498 error = ETIMEDOUT; 499 else if (error == ERESTART) { 500 if (timo != 0) 501 error = EINTR; 502 } 503 return (error); 504 } 505 506 int 507 sys_thr_wake(struct thread *td, struct thr_wake_args *uap) 508 /* long id */ 509 { 510 struct proc *p; 511 struct thread *ttd; 512 513 if (uap->id == td->td_tid) { 514 td->td_pflags |= TDP_WAKEUP; 515 return (0); 516 } 517 518 p = td->td_proc; 519 ttd = tdfind((lwpid_t)uap->id, p->p_pid); 520 if (ttd == NULL) 521 return (ESRCH); 522 thread_lock(ttd); 523 ttd->td_flags |= TDF_THRWAKEUP; 524 thread_unlock(ttd); 525 wakeup((void *)ttd); 526 PROC_UNLOCK(p); 527 return (0); 528 } 529 530 int 531 sys_thr_set_name(struct thread *td, struct thr_set_name_args *uap) 532 { 533 struct proc *p; 534 char name[MAXCOMLEN + 1]; 535 struct thread *ttd; 536 int error; 537 538 error = 0; 539 name[0] = '\0'; 540 if (uap->name != NULL) { 541 error = copyinstr(uap->name, name, sizeof(name), 542 NULL); 543 if (error) 544 return (error); 545 } 546 p = td->td_proc; 547 ttd = tdfind((lwpid_t)uap->id, p->p_pid); 548 if (ttd == NULL) 549 return (ESRCH); 550 strcpy(ttd->td_name, name); 551 PROC_UNLOCK(p); 552 return (error); 553 } 554