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 thread_link(newtd, p); 256 bcopy(p->p_comm, newtd->td_name, sizeof(newtd->td_name)); 257 thread_lock(td); 258 /* let the scheduler know about these things. */ 259 sched_fork_thread(td, newtd); 260 thread_unlock(td); 261 if (P_SHOULDSTOP(p)) 262 newtd->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK; 263 PROC_UNLOCK(p); 264 265 tidhash_add(newtd); 266 267 thread_lock(newtd); 268 if (rtp != NULL) { 269 if (!(td->td_pri_class == PRI_TIMESHARE && 270 rtp->type == RTP_PRIO_NORMAL)) { 271 rtp_to_pri(rtp, newtd); 272 sched_prio(newtd, newtd->td_user_pri); 273 } /* ignore timesharing class */ 274 } 275 TD_SET_CAN_RUN(newtd); 276 sched_add(newtd, SRQ_BORING); 277 thread_unlock(newtd); 278 279 return (0); 280 281 fail: 282 #ifdef RACCT 283 PROC_LOCK(p); 284 racct_sub(p, RACCT_NTHR, 1); 285 PROC_UNLOCK(p); 286 #endif 287 return (error); 288 } 289 290 int 291 sys_thr_self(struct thread *td, struct thr_self_args *uap) 292 /* long *id */ 293 { 294 int error; 295 296 error = suword_lwpid(uap->id, (unsigned)td->td_tid); 297 if (error == -1) 298 return (EFAULT); 299 return (0); 300 } 301 302 int 303 sys_thr_exit(struct thread *td, struct thr_exit_args *uap) 304 /* long *state */ 305 { 306 struct proc *p; 307 308 p = td->td_proc; 309 310 /* Signal userland that it can free the stack. */ 311 if ((void *)uap->state != NULL) { 312 suword_lwpid(uap->state, 1); 313 kern_umtx_wake(td, uap->state, INT_MAX, 0); 314 } 315 316 rw_wlock(&tidhash_lock); 317 318 PROC_LOCK(p); 319 320 if (p->p_numthreads != 1) { 321 racct_sub(p, RACCT_NTHR, 1); 322 LIST_REMOVE(td, td_hash); 323 rw_wunlock(&tidhash_lock); 324 tdsigcleanup(td); 325 umtx_thread_exit(td); 326 PROC_SLOCK(p); 327 thread_stopped(p); 328 thread_exit(); 329 /* NOTREACHED */ 330 } 331 332 /* 333 * Ignore attempts to shut down last thread in the proc. This 334 * will actually call _exit(2) in the usermode trampoline when 335 * it returns. 336 */ 337 PROC_UNLOCK(p); 338 rw_wunlock(&tidhash_lock); 339 return (0); 340 } 341 342 int 343 sys_thr_kill(struct thread *td, struct thr_kill_args *uap) 344 /* long id, int sig */ 345 { 346 ksiginfo_t ksi; 347 struct thread *ttd; 348 struct proc *p; 349 int error; 350 351 p = td->td_proc; 352 ksiginfo_init(&ksi); 353 ksi.ksi_signo = uap->sig; 354 ksi.ksi_code = SI_LWP; 355 ksi.ksi_pid = p->p_pid; 356 ksi.ksi_uid = td->td_ucred->cr_ruid; 357 if (uap->id == -1) { 358 if (uap->sig != 0 && !_SIG_VALID(uap->sig)) { 359 error = EINVAL; 360 } else { 361 error = ESRCH; 362 PROC_LOCK(p); 363 FOREACH_THREAD_IN_PROC(p, ttd) { 364 if (ttd != td) { 365 error = 0; 366 if (uap->sig == 0) 367 break; 368 tdksignal(ttd, uap->sig, &ksi); 369 } 370 } 371 PROC_UNLOCK(p); 372 } 373 } else { 374 error = 0; 375 ttd = tdfind((lwpid_t)uap->id, p->p_pid); 376 if (ttd == NULL) 377 return (ESRCH); 378 if (uap->sig == 0) 379 ; 380 else if (!_SIG_VALID(uap->sig)) 381 error = EINVAL; 382 else 383 tdksignal(ttd, uap->sig, &ksi); 384 PROC_UNLOCK(ttd->td_proc); 385 } 386 return (error); 387 } 388 389 int 390 sys_thr_kill2(struct thread *td, struct thr_kill2_args *uap) 391 /* pid_t pid, long id, int sig */ 392 { 393 ksiginfo_t ksi; 394 struct thread *ttd; 395 struct proc *p; 396 int error; 397 398 AUDIT_ARG_SIGNUM(uap->sig); 399 400 ksiginfo_init(&ksi); 401 ksi.ksi_signo = uap->sig; 402 ksi.ksi_code = SI_LWP; 403 ksi.ksi_pid = td->td_proc->p_pid; 404 ksi.ksi_uid = td->td_ucred->cr_ruid; 405 if (uap->id == -1) { 406 if ((p = pfind(uap->pid)) == NULL) 407 return (ESRCH); 408 AUDIT_ARG_PROCESS(p); 409 error = p_cansignal(td, p, uap->sig); 410 if (error) { 411 PROC_UNLOCK(p); 412 return (error); 413 } 414 if (uap->sig != 0 && !_SIG_VALID(uap->sig)) { 415 error = EINVAL; 416 } else { 417 error = ESRCH; 418 FOREACH_THREAD_IN_PROC(p, ttd) { 419 if (ttd != td) { 420 error = 0; 421 if (uap->sig == 0) 422 break; 423 tdksignal(ttd, uap->sig, &ksi); 424 } 425 } 426 } 427 PROC_UNLOCK(p); 428 } else { 429 ttd = tdfind((lwpid_t)uap->id, uap->pid); 430 if (ttd == NULL) 431 return (ESRCH); 432 p = ttd->td_proc; 433 AUDIT_ARG_PROCESS(p); 434 error = p_cansignal(td, p, uap->sig); 435 if (uap->sig == 0) 436 ; 437 else if (!_SIG_VALID(uap->sig)) 438 error = EINVAL; 439 else 440 tdksignal(ttd, uap->sig, &ksi); 441 PROC_UNLOCK(p); 442 } 443 return (error); 444 } 445 446 int 447 sys_thr_suspend(struct thread *td, struct thr_suspend_args *uap) 448 /* const struct timespec *timeout */ 449 { 450 struct timespec ts, *tsp; 451 int error; 452 453 tsp = NULL; 454 if (uap->timeout != NULL) { 455 error = umtx_copyin_timeout(uap->timeout, &ts); 456 if (error != 0) 457 return (error); 458 tsp = &ts; 459 } 460 461 return (kern_thr_suspend(td, tsp)); 462 } 463 464 int 465 kern_thr_suspend(struct thread *td, struct timespec *tsp) 466 { 467 struct proc *p = td->td_proc; 468 struct timeval tv; 469 int error = 0; 470 int timo = 0; 471 472 if (td->td_pflags & TDP_WAKEUP) { 473 td->td_pflags &= ~TDP_WAKEUP; 474 return (0); 475 } 476 477 if (tsp != NULL) { 478 if (tsp->tv_sec == 0 && tsp->tv_nsec == 0) 479 error = EWOULDBLOCK; 480 else { 481 TIMESPEC_TO_TIMEVAL(&tv, tsp); 482 timo = tvtohz(&tv); 483 } 484 } 485 486 PROC_LOCK(p); 487 if (error == 0 && (td->td_flags & TDF_THRWAKEUP) == 0) 488 error = msleep((void *)td, &p->p_mtx, 489 PCATCH, "lthr", timo); 490 491 if (td->td_flags & TDF_THRWAKEUP) { 492 thread_lock(td); 493 td->td_flags &= ~TDF_THRWAKEUP; 494 thread_unlock(td); 495 PROC_UNLOCK(p); 496 return (0); 497 } 498 PROC_UNLOCK(p); 499 if (error == EWOULDBLOCK) 500 error = ETIMEDOUT; 501 else if (error == ERESTART) { 502 if (timo != 0) 503 error = EINTR; 504 } 505 return (error); 506 } 507 508 int 509 sys_thr_wake(struct thread *td, struct thr_wake_args *uap) 510 /* long id */ 511 { 512 struct proc *p; 513 struct thread *ttd; 514 515 if (uap->id == td->td_tid) { 516 td->td_pflags |= TDP_WAKEUP; 517 return (0); 518 } 519 520 p = td->td_proc; 521 ttd = tdfind((lwpid_t)uap->id, p->p_pid); 522 if (ttd == NULL) 523 return (ESRCH); 524 thread_lock(ttd); 525 ttd->td_flags |= TDF_THRWAKEUP; 526 thread_unlock(ttd); 527 wakeup((void *)ttd); 528 PROC_UNLOCK(p); 529 return (0); 530 } 531 532 int 533 sys_thr_set_name(struct thread *td, struct thr_set_name_args *uap) 534 { 535 struct proc *p; 536 char name[MAXCOMLEN + 1]; 537 struct thread *ttd; 538 int error; 539 540 error = 0; 541 name[0] = '\0'; 542 if (uap->name != NULL) { 543 error = copyinstr(uap->name, name, sizeof(name), 544 NULL); 545 if (error) 546 return (error); 547 } 548 p = td->td_proc; 549 ttd = tdfind((lwpid_t)uap->id, p->p_pid); 550 if (ttd == NULL) 551 return (ESRCH); 552 strcpy(ttd->td_name, name); 553 #ifdef KTR 554 sched_clear_tdname(ttd); 555 #endif 556 PROC_UNLOCK(p); 557 return (error); 558 } 559