1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1982, 1986, 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * (c) UNIX System Laboratories, Inc. 7 * All or some portions of this file are derived from material licensed 8 * to the University of California by American Telephone and Telegraph 9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 10 * the permission of UNIX System Laboratories, Inc. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)kern_resource.c 8.5 (Berkeley) 1/21/94 37 */ 38 39 #include <sys/cdefs.h> 40 __FBSDID("$FreeBSD$"); 41 42 #include <sys/param.h> 43 #include <sys/systm.h> 44 #include <sys/sysproto.h> 45 #include <sys/file.h> 46 #include <sys/kernel.h> 47 #include <sys/lock.h> 48 #include <sys/malloc.h> 49 #include <sys/mutex.h> 50 #include <sys/priv.h> 51 #include <sys/proc.h> 52 #include <sys/refcount.h> 53 #include <sys/racct.h> 54 #include <sys/resourcevar.h> 55 #include <sys/rwlock.h> 56 #include <sys/sched.h> 57 #include <sys/sx.h> 58 #include <sys/syscallsubr.h> 59 #include <sys/sysctl.h> 60 #include <sys/sysent.h> 61 #include <sys/time.h> 62 #include <sys/umtxvar.h> 63 64 #include <vm/vm.h> 65 #include <vm/vm_param.h> 66 #include <vm/pmap.h> 67 #include <vm/vm_map.h> 68 69 static MALLOC_DEFINE(M_PLIMIT, "plimit", "plimit structures"); 70 static MALLOC_DEFINE(M_UIDINFO, "uidinfo", "uidinfo structures"); 71 #define UIHASH(uid) (&uihashtbl[(uid) & uihash]) 72 static struct rwlock uihashtbl_lock; 73 static LIST_HEAD(uihashhead, uidinfo) *uihashtbl; 74 static u_long uihash; /* size of hash table - 1 */ 75 76 static void calcru1(struct proc *p, struct rusage_ext *ruxp, 77 struct timeval *up, struct timeval *sp); 78 static int donice(struct thread *td, struct proc *chgp, int n); 79 static struct uidinfo *uilookup(uid_t uid); 80 static void ruxagg_ext_locked(struct rusage_ext *rux, struct thread *td); 81 82 /* 83 * Resource controls and accounting. 84 */ 85 #ifndef _SYS_SYSPROTO_H_ 86 struct getpriority_args { 87 int which; 88 int who; 89 }; 90 #endif 91 int 92 sys_getpriority(struct thread *td, struct getpriority_args *uap) 93 { 94 95 return (kern_getpriority(td, uap->which, uap->who)); 96 } 97 98 int 99 kern_getpriority(struct thread *td, int which, int who) 100 { 101 struct proc *p; 102 struct pgrp *pg; 103 int error, low; 104 105 error = 0; 106 low = PRIO_MAX + 1; 107 switch (which) { 108 case PRIO_PROCESS: 109 if (who == 0) 110 low = td->td_proc->p_nice; 111 else { 112 p = pfind(who); 113 if (p == NULL) 114 break; 115 if (p_cansee(td, p) == 0) 116 low = p->p_nice; 117 PROC_UNLOCK(p); 118 } 119 break; 120 121 case PRIO_PGRP: 122 sx_slock(&proctree_lock); 123 if (who == 0) { 124 pg = td->td_proc->p_pgrp; 125 PGRP_LOCK(pg); 126 } else { 127 pg = pgfind(who); 128 if (pg == NULL) { 129 sx_sunlock(&proctree_lock); 130 break; 131 } 132 } 133 sx_sunlock(&proctree_lock); 134 LIST_FOREACH(p, &pg->pg_members, p_pglist) { 135 PROC_LOCK(p); 136 if (p->p_state == PRS_NORMAL && 137 p_cansee(td, p) == 0) { 138 if (p->p_nice < low) 139 low = p->p_nice; 140 } 141 PROC_UNLOCK(p); 142 } 143 PGRP_UNLOCK(pg); 144 break; 145 146 case PRIO_USER: 147 if (who == 0) 148 who = td->td_ucred->cr_uid; 149 sx_slock(&allproc_lock); 150 FOREACH_PROC_IN_SYSTEM(p) { 151 PROC_LOCK(p); 152 if (p->p_state == PRS_NORMAL && 153 p_cansee(td, p) == 0 && 154 p->p_ucred->cr_uid == who) { 155 if (p->p_nice < low) 156 low = p->p_nice; 157 } 158 PROC_UNLOCK(p); 159 } 160 sx_sunlock(&allproc_lock); 161 break; 162 163 default: 164 error = EINVAL; 165 break; 166 } 167 if (low == PRIO_MAX + 1 && error == 0) 168 error = ESRCH; 169 td->td_retval[0] = low; 170 return (error); 171 } 172 173 #ifndef _SYS_SYSPROTO_H_ 174 struct setpriority_args { 175 int which; 176 int who; 177 int prio; 178 }; 179 #endif 180 int 181 sys_setpriority(struct thread *td, struct setpriority_args *uap) 182 { 183 184 return (kern_setpriority(td, uap->which, uap->who, uap->prio)); 185 } 186 187 int 188 kern_setpriority(struct thread *td, int which, int who, int prio) 189 { 190 struct proc *curp, *p; 191 struct pgrp *pg; 192 int found = 0, error = 0; 193 194 curp = td->td_proc; 195 switch (which) { 196 case PRIO_PROCESS: 197 if (who == 0) { 198 PROC_LOCK(curp); 199 error = donice(td, curp, prio); 200 PROC_UNLOCK(curp); 201 } else { 202 p = pfind(who); 203 if (p == NULL) 204 break; 205 error = p_cansee(td, p); 206 if (error == 0) 207 error = donice(td, p, prio); 208 PROC_UNLOCK(p); 209 } 210 found++; 211 break; 212 213 case PRIO_PGRP: 214 sx_slock(&proctree_lock); 215 if (who == 0) { 216 pg = curp->p_pgrp; 217 PGRP_LOCK(pg); 218 } else { 219 pg = pgfind(who); 220 if (pg == NULL) { 221 sx_sunlock(&proctree_lock); 222 break; 223 } 224 } 225 sx_sunlock(&proctree_lock); 226 LIST_FOREACH(p, &pg->pg_members, p_pglist) { 227 PROC_LOCK(p); 228 if (p->p_state == PRS_NORMAL && 229 p_cansee(td, p) == 0) { 230 error = donice(td, p, prio); 231 found++; 232 } 233 PROC_UNLOCK(p); 234 } 235 PGRP_UNLOCK(pg); 236 break; 237 238 case PRIO_USER: 239 if (who == 0) 240 who = td->td_ucred->cr_uid; 241 sx_slock(&allproc_lock); 242 FOREACH_PROC_IN_SYSTEM(p) { 243 PROC_LOCK(p); 244 if (p->p_state == PRS_NORMAL && 245 p->p_ucred->cr_uid == who && 246 p_cansee(td, p) == 0) { 247 error = donice(td, p, prio); 248 found++; 249 } 250 PROC_UNLOCK(p); 251 } 252 sx_sunlock(&allproc_lock); 253 break; 254 255 default: 256 error = EINVAL; 257 break; 258 } 259 if (found == 0 && error == 0) 260 error = ESRCH; 261 return (error); 262 } 263 264 /* 265 * Set "nice" for a (whole) process. 266 */ 267 static int 268 donice(struct thread *td, struct proc *p, int n) 269 { 270 int error; 271 272 PROC_LOCK_ASSERT(p, MA_OWNED); 273 if ((error = p_cansched(td, p))) 274 return (error); 275 if (n > PRIO_MAX) 276 n = PRIO_MAX; 277 if (n < PRIO_MIN) 278 n = PRIO_MIN; 279 if (n < p->p_nice && priv_check(td, PRIV_SCHED_SETPRIORITY) != 0) 280 return (EACCES); 281 sched_nice(p, n); 282 return (0); 283 } 284 285 static int unprivileged_idprio; 286 SYSCTL_INT(_security_bsd, OID_AUTO, unprivileged_idprio, CTLFLAG_RW, 287 &unprivileged_idprio, 0, "Allow non-root users to set an idle priority"); 288 289 /* 290 * Set realtime priority for LWP. 291 */ 292 #ifndef _SYS_SYSPROTO_H_ 293 struct rtprio_thread_args { 294 int function; 295 lwpid_t lwpid; 296 struct rtprio *rtp; 297 }; 298 #endif 299 int 300 sys_rtprio_thread(struct thread *td, struct rtprio_thread_args *uap) 301 { 302 struct proc *p; 303 struct rtprio rtp; 304 struct thread *td1; 305 int cierror, error; 306 307 /* Perform copyin before acquiring locks if needed. */ 308 if (uap->function == RTP_SET) 309 cierror = copyin(uap->rtp, &rtp, sizeof(struct rtprio)); 310 else 311 cierror = 0; 312 313 if (uap->lwpid == 0 || uap->lwpid == td->td_tid) { 314 p = td->td_proc; 315 td1 = td; 316 PROC_LOCK(p); 317 } else { 318 td1 = tdfind(uap->lwpid, -1); 319 if (td1 == NULL) 320 return (ESRCH); 321 p = td1->td_proc; 322 } 323 324 switch (uap->function) { 325 case RTP_LOOKUP: 326 if ((error = p_cansee(td, p))) 327 break; 328 pri_to_rtp(td1, &rtp); 329 PROC_UNLOCK(p); 330 return (copyout(&rtp, uap->rtp, sizeof(struct rtprio))); 331 case RTP_SET: 332 if ((error = p_cansched(td, p)) || (error = cierror)) 333 break; 334 335 /* Disallow setting rtprio in most cases if not superuser. */ 336 337 /* 338 * Realtime priority has to be restricted for reasons which 339 * should be obvious. However, for idleprio processes, there is 340 * a potential for system deadlock if an idleprio process gains 341 * a lock on a resource that other processes need (and the 342 * idleprio process can't run due to a CPU-bound normal 343 * process). Fix me! XXX 344 * 345 * This problem is not only related to idleprio process. 346 * A user level program can obtain a file lock and hold it 347 * indefinitely. Additionally, without idleprio processes it is 348 * still conceivable that a program with low priority will never 349 * get to run. In short, allowing this feature might make it 350 * easier to lock a resource indefinitely, but it is not the 351 * only thing that makes it possible. 352 */ 353 if (RTP_PRIO_BASE(rtp.type) == RTP_PRIO_REALTIME || 354 (RTP_PRIO_BASE(rtp.type) == RTP_PRIO_IDLE && 355 unprivileged_idprio == 0)) { 356 error = priv_check(td, PRIV_SCHED_RTPRIO); 357 if (error) 358 break; 359 } 360 error = rtp_to_pri(&rtp, td1); 361 break; 362 default: 363 error = EINVAL; 364 break; 365 } 366 PROC_UNLOCK(p); 367 return (error); 368 } 369 370 /* 371 * Set realtime priority. 372 */ 373 #ifndef _SYS_SYSPROTO_H_ 374 struct rtprio_args { 375 int function; 376 pid_t pid; 377 struct rtprio *rtp; 378 }; 379 #endif 380 int 381 sys_rtprio(struct thread *td, struct rtprio_args *uap) 382 { 383 struct proc *p; 384 struct thread *tdp; 385 struct rtprio rtp; 386 int cierror, error; 387 388 /* Perform copyin before acquiring locks if needed. */ 389 if (uap->function == RTP_SET) 390 cierror = copyin(uap->rtp, &rtp, sizeof(struct rtprio)); 391 else 392 cierror = 0; 393 394 if (uap->pid == 0) { 395 p = td->td_proc; 396 PROC_LOCK(p); 397 } else { 398 p = pfind(uap->pid); 399 if (p == NULL) 400 return (ESRCH); 401 } 402 403 switch (uap->function) { 404 case RTP_LOOKUP: 405 if ((error = p_cansee(td, p))) 406 break; 407 /* 408 * Return OUR priority if no pid specified, 409 * or if one is, report the highest priority 410 * in the process. There isn't much more you can do as 411 * there is only room to return a single priority. 412 * Note: specifying our own pid is not the same 413 * as leaving it zero. 414 */ 415 if (uap->pid == 0) { 416 pri_to_rtp(td, &rtp); 417 } else { 418 struct rtprio rtp2; 419 420 rtp.type = RTP_PRIO_IDLE; 421 rtp.prio = RTP_PRIO_MAX; 422 FOREACH_THREAD_IN_PROC(p, tdp) { 423 pri_to_rtp(tdp, &rtp2); 424 if (rtp2.type < rtp.type || 425 (rtp2.type == rtp.type && 426 rtp2.prio < rtp.prio)) { 427 rtp.type = rtp2.type; 428 rtp.prio = rtp2.prio; 429 } 430 } 431 } 432 PROC_UNLOCK(p); 433 return (copyout(&rtp, uap->rtp, sizeof(struct rtprio))); 434 case RTP_SET: 435 if ((error = p_cansched(td, p)) || (error = cierror)) 436 break; 437 438 /* 439 * Disallow setting rtprio in most cases if not superuser. 440 * See the comment in sys_rtprio_thread about idprio 441 * threads holding a lock. 442 */ 443 if (RTP_PRIO_BASE(rtp.type) == RTP_PRIO_REALTIME || 444 (RTP_PRIO_BASE(rtp.type) == RTP_PRIO_IDLE && 445 !unprivileged_idprio)) { 446 error = priv_check(td, PRIV_SCHED_RTPRIO); 447 if (error) 448 break; 449 } 450 451 /* 452 * If we are setting our own priority, set just our 453 * thread but if we are doing another process, 454 * do all the threads on that process. If we 455 * specify our own pid we do the latter. 456 */ 457 if (uap->pid == 0) { 458 error = rtp_to_pri(&rtp, td); 459 } else { 460 FOREACH_THREAD_IN_PROC(p, td) { 461 if ((error = rtp_to_pri(&rtp, td)) != 0) 462 break; 463 } 464 } 465 break; 466 default: 467 error = EINVAL; 468 break; 469 } 470 PROC_UNLOCK(p); 471 return (error); 472 } 473 474 int 475 rtp_to_pri(struct rtprio *rtp, struct thread *td) 476 { 477 u_char newpri, oldclass, oldpri; 478 479 switch (RTP_PRIO_BASE(rtp->type)) { 480 case RTP_PRIO_REALTIME: 481 if (rtp->prio > RTP_PRIO_MAX) 482 return (EINVAL); 483 newpri = PRI_MIN_REALTIME + rtp->prio; 484 break; 485 case RTP_PRIO_NORMAL: 486 if (rtp->prio > (PRI_MAX_TIMESHARE - PRI_MIN_TIMESHARE)) 487 return (EINVAL); 488 newpri = PRI_MIN_TIMESHARE + rtp->prio; 489 break; 490 case RTP_PRIO_IDLE: 491 if (rtp->prio > RTP_PRIO_MAX) 492 return (EINVAL); 493 newpri = PRI_MIN_IDLE + rtp->prio; 494 break; 495 default: 496 return (EINVAL); 497 } 498 499 thread_lock(td); 500 oldclass = td->td_pri_class; 501 sched_class(td, rtp->type); /* XXX fix */ 502 oldpri = td->td_user_pri; 503 sched_user_prio(td, newpri); 504 if (td->td_user_pri != oldpri && (oldclass != RTP_PRIO_NORMAL || 505 td->td_pri_class != RTP_PRIO_NORMAL)) 506 sched_prio(td, td->td_user_pri); 507 if (TD_ON_UPILOCK(td) && oldpri != newpri) { 508 critical_enter(); 509 thread_unlock(td); 510 umtx_pi_adjust(td, oldpri); 511 critical_exit(); 512 } else 513 thread_unlock(td); 514 return (0); 515 } 516 517 void 518 pri_to_rtp(struct thread *td, struct rtprio *rtp) 519 { 520 521 thread_lock(td); 522 switch (PRI_BASE(td->td_pri_class)) { 523 case PRI_REALTIME: 524 rtp->prio = td->td_base_user_pri - PRI_MIN_REALTIME; 525 break; 526 case PRI_TIMESHARE: 527 rtp->prio = td->td_base_user_pri - PRI_MIN_TIMESHARE; 528 break; 529 case PRI_IDLE: 530 rtp->prio = td->td_base_user_pri - PRI_MIN_IDLE; 531 break; 532 default: 533 break; 534 } 535 rtp->type = td->td_pri_class; 536 thread_unlock(td); 537 } 538 539 #if defined(COMPAT_43) 540 #ifndef _SYS_SYSPROTO_H_ 541 struct osetrlimit_args { 542 u_int which; 543 struct orlimit *rlp; 544 }; 545 #endif 546 int 547 osetrlimit(struct thread *td, struct osetrlimit_args *uap) 548 { 549 struct orlimit olim; 550 struct rlimit lim; 551 int error; 552 553 if ((error = copyin(uap->rlp, &olim, sizeof(struct orlimit)))) 554 return (error); 555 lim.rlim_cur = olim.rlim_cur; 556 lim.rlim_max = olim.rlim_max; 557 error = kern_setrlimit(td, uap->which, &lim); 558 return (error); 559 } 560 561 #ifndef _SYS_SYSPROTO_H_ 562 struct ogetrlimit_args { 563 u_int which; 564 struct orlimit *rlp; 565 }; 566 #endif 567 int 568 ogetrlimit(struct thread *td, struct ogetrlimit_args *uap) 569 { 570 struct orlimit olim; 571 struct rlimit rl; 572 int error; 573 574 if (uap->which >= RLIM_NLIMITS) 575 return (EINVAL); 576 lim_rlimit(td, uap->which, &rl); 577 578 /* 579 * XXX would be more correct to convert only RLIM_INFINITY to the 580 * old RLIM_INFINITY and fail with EOVERFLOW for other larger 581 * values. Most 64->32 and 32->16 conversions, including not 582 * unimportant ones of uids are even more broken than what we 583 * do here (they blindly truncate). We don't do this correctly 584 * here since we have little experience with EOVERFLOW yet. 585 * Elsewhere, getuid() can't fail... 586 */ 587 olim.rlim_cur = rl.rlim_cur > 0x7fffffff ? 0x7fffffff : rl.rlim_cur; 588 olim.rlim_max = rl.rlim_max > 0x7fffffff ? 0x7fffffff : rl.rlim_max; 589 error = copyout(&olim, uap->rlp, sizeof(olim)); 590 return (error); 591 } 592 #endif /* COMPAT_43 */ 593 594 #ifndef _SYS_SYSPROTO_H_ 595 struct __setrlimit_args { 596 u_int which; 597 struct rlimit *rlp; 598 }; 599 #endif 600 int 601 sys_setrlimit(struct thread *td, struct __setrlimit_args *uap) 602 { 603 struct rlimit alim; 604 int error; 605 606 if ((error = copyin(uap->rlp, &alim, sizeof(struct rlimit)))) 607 return (error); 608 error = kern_setrlimit(td, uap->which, &alim); 609 return (error); 610 } 611 612 static void 613 lim_cb(void *arg) 614 { 615 struct rlimit rlim; 616 struct thread *td; 617 struct proc *p; 618 619 p = arg; 620 PROC_LOCK_ASSERT(p, MA_OWNED); 621 /* 622 * Check if the process exceeds its cpu resource allocation. If 623 * it reaches the max, arrange to kill the process in ast(). 624 */ 625 if (p->p_cpulimit == RLIM_INFINITY) 626 return; 627 PROC_STATLOCK(p); 628 FOREACH_THREAD_IN_PROC(p, td) { 629 ruxagg(p, td); 630 } 631 PROC_STATUNLOCK(p); 632 if (p->p_rux.rux_runtime > p->p_cpulimit * cpu_tickrate()) { 633 lim_rlimit_proc(p, RLIMIT_CPU, &rlim); 634 if (p->p_rux.rux_runtime >= rlim.rlim_max * cpu_tickrate()) { 635 killproc(p, "exceeded maximum CPU limit"); 636 } else { 637 if (p->p_cpulimit < rlim.rlim_max) 638 p->p_cpulimit += 5; 639 kern_psignal(p, SIGXCPU); 640 } 641 } 642 if ((p->p_flag & P_WEXIT) == 0) 643 callout_reset_sbt(&p->p_limco, SBT_1S, 0, 644 lim_cb, p, C_PREL(1)); 645 } 646 647 int 648 kern_setrlimit(struct thread *td, u_int which, struct rlimit *limp) 649 { 650 651 return (kern_proc_setrlimit(td, td->td_proc, which, limp)); 652 } 653 654 int 655 kern_proc_setrlimit(struct thread *td, struct proc *p, u_int which, 656 struct rlimit *limp) 657 { 658 struct plimit *newlim, *oldlim; 659 struct rlimit *alimp; 660 struct rlimit oldssiz; 661 int error; 662 663 if (which >= RLIM_NLIMITS) 664 return (EINVAL); 665 666 /* 667 * Preserve historical bugs by treating negative limits as unsigned. 668 */ 669 if (limp->rlim_cur < 0) 670 limp->rlim_cur = RLIM_INFINITY; 671 if (limp->rlim_max < 0) 672 limp->rlim_max = RLIM_INFINITY; 673 674 if (which == RLIMIT_STACK && limp->rlim_cur != RLIM_INFINITY) 675 limp->rlim_cur += p->p_vmspace->vm_stkgap; 676 677 oldssiz.rlim_cur = 0; 678 newlim = lim_alloc(); 679 PROC_LOCK(p); 680 oldlim = p->p_limit; 681 alimp = &oldlim->pl_rlimit[which]; 682 if (limp->rlim_cur > alimp->rlim_max || 683 limp->rlim_max > alimp->rlim_max) 684 if ((error = priv_check(td, PRIV_PROC_SETRLIMIT))) { 685 PROC_UNLOCK(p); 686 lim_free(newlim); 687 return (error); 688 } 689 if (limp->rlim_cur > limp->rlim_max) 690 limp->rlim_cur = limp->rlim_max; 691 lim_copy(newlim, oldlim); 692 alimp = &newlim->pl_rlimit[which]; 693 694 switch (which) { 695 case RLIMIT_CPU: 696 if (limp->rlim_cur != RLIM_INFINITY && 697 p->p_cpulimit == RLIM_INFINITY) 698 callout_reset_sbt(&p->p_limco, SBT_1S, 0, 699 lim_cb, p, C_PREL(1)); 700 p->p_cpulimit = limp->rlim_cur; 701 break; 702 case RLIMIT_DATA: 703 if (limp->rlim_cur > maxdsiz) 704 limp->rlim_cur = maxdsiz; 705 if (limp->rlim_max > maxdsiz) 706 limp->rlim_max = maxdsiz; 707 break; 708 709 case RLIMIT_STACK: 710 if (limp->rlim_cur > maxssiz) 711 limp->rlim_cur = maxssiz; 712 if (limp->rlim_max > maxssiz) 713 limp->rlim_max = maxssiz; 714 oldssiz = *alimp; 715 if (p->p_sysent->sv_fixlimit != NULL) 716 p->p_sysent->sv_fixlimit(&oldssiz, 717 RLIMIT_STACK); 718 break; 719 720 case RLIMIT_NOFILE: 721 if (limp->rlim_cur > maxfilesperproc) 722 limp->rlim_cur = maxfilesperproc; 723 if (limp->rlim_max > maxfilesperproc) 724 limp->rlim_max = maxfilesperproc; 725 break; 726 727 case RLIMIT_NPROC: 728 if (limp->rlim_cur > maxprocperuid) 729 limp->rlim_cur = maxprocperuid; 730 if (limp->rlim_max > maxprocperuid) 731 limp->rlim_max = maxprocperuid; 732 if (limp->rlim_cur < 1) 733 limp->rlim_cur = 1; 734 if (limp->rlim_max < 1) 735 limp->rlim_max = 1; 736 break; 737 } 738 if (p->p_sysent->sv_fixlimit != NULL) 739 p->p_sysent->sv_fixlimit(limp, which); 740 *alimp = *limp; 741 p->p_limit = newlim; 742 PROC_UPDATE_COW(p); 743 PROC_UNLOCK(p); 744 lim_free(oldlim); 745 746 if (which == RLIMIT_STACK && 747 /* 748 * Skip calls from exec_new_vmspace(), done when stack is 749 * not mapped yet. 750 */ 751 (td != curthread || (p->p_flag & P_INEXEC) == 0)) { 752 /* 753 * Stack is allocated to the max at exec time with only 754 * "rlim_cur" bytes accessible. If stack limit is going 755 * up make more accessible, if going down make inaccessible. 756 */ 757 if (limp->rlim_cur != oldssiz.rlim_cur) { 758 vm_offset_t addr; 759 vm_size_t size; 760 vm_prot_t prot; 761 762 if (limp->rlim_cur > oldssiz.rlim_cur) { 763 prot = p->p_sysent->sv_stackprot; 764 size = limp->rlim_cur - oldssiz.rlim_cur; 765 addr = p->p_sysent->sv_usrstack - 766 limp->rlim_cur; 767 } else { 768 prot = VM_PROT_NONE; 769 size = oldssiz.rlim_cur - limp->rlim_cur; 770 addr = p->p_sysent->sv_usrstack - 771 oldssiz.rlim_cur; 772 } 773 addr = trunc_page(addr); 774 size = round_page(size); 775 (void)vm_map_protect(&p->p_vmspace->vm_map, 776 addr, addr + size, prot, 0, 777 VM_MAP_PROTECT_SET_PROT); 778 } 779 } 780 781 return (0); 782 } 783 784 #ifndef _SYS_SYSPROTO_H_ 785 struct __getrlimit_args { 786 u_int which; 787 struct rlimit *rlp; 788 }; 789 #endif 790 /* ARGSUSED */ 791 int 792 sys_getrlimit(struct thread *td, struct __getrlimit_args *uap) 793 { 794 struct rlimit rlim; 795 int error; 796 797 if (uap->which >= RLIM_NLIMITS) 798 return (EINVAL); 799 lim_rlimit(td, uap->which, &rlim); 800 error = copyout(&rlim, uap->rlp, sizeof(struct rlimit)); 801 return (error); 802 } 803 804 /* 805 * Transform the running time and tick information for children of proc p 806 * into user and system time usage. 807 */ 808 void 809 calccru(struct proc *p, struct timeval *up, struct timeval *sp) 810 { 811 812 PROC_LOCK_ASSERT(p, MA_OWNED); 813 calcru1(p, &p->p_crux, up, sp); 814 } 815 816 /* 817 * Transform the running time and tick information in proc p into user 818 * and system time usage. If appropriate, include the current time slice 819 * on this CPU. 820 */ 821 void 822 calcru(struct proc *p, struct timeval *up, struct timeval *sp) 823 { 824 struct thread *td; 825 uint64_t runtime, u; 826 827 PROC_LOCK_ASSERT(p, MA_OWNED); 828 PROC_STATLOCK_ASSERT(p, MA_OWNED); 829 /* 830 * If we are getting stats for the current process, then add in the 831 * stats that this thread has accumulated in its current time slice. 832 * We reset the thread and CPU state as if we had performed a context 833 * switch right here. 834 */ 835 td = curthread; 836 if (td->td_proc == p) { 837 u = cpu_ticks(); 838 runtime = u - PCPU_GET(switchtime); 839 td->td_runtime += runtime; 840 td->td_incruntime += runtime; 841 PCPU_SET(switchtime, u); 842 } 843 /* Make sure the per-thread stats are current. */ 844 FOREACH_THREAD_IN_PROC(p, td) { 845 if (td->td_incruntime == 0) 846 continue; 847 ruxagg(p, td); 848 } 849 calcru1(p, &p->p_rux, up, sp); 850 } 851 852 /* Collect resource usage for a single thread. */ 853 void 854 rufetchtd(struct thread *td, struct rusage *ru) 855 { 856 struct proc *p; 857 uint64_t runtime, u; 858 859 p = td->td_proc; 860 PROC_STATLOCK_ASSERT(p, MA_OWNED); 861 THREAD_LOCK_ASSERT(td, MA_OWNED); 862 /* 863 * If we are getting stats for the current thread, then add in the 864 * stats that this thread has accumulated in its current time slice. 865 * We reset the thread and CPU state as if we had performed a context 866 * switch right here. 867 */ 868 if (td == curthread) { 869 u = cpu_ticks(); 870 runtime = u - PCPU_GET(switchtime); 871 td->td_runtime += runtime; 872 td->td_incruntime += runtime; 873 PCPU_SET(switchtime, u); 874 } 875 ruxagg_locked(p, td); 876 *ru = td->td_ru; 877 calcru1(p, &td->td_rux, &ru->ru_utime, &ru->ru_stime); 878 } 879 880 /* XXX: the MI version is too slow to use: */ 881 #ifndef __HAVE_INLINE_FLSLL 882 #define flsll(x) (fls((x) >> 32) != 0 ? fls((x) >> 32) + 32 : fls(x)) 883 #endif 884 885 static uint64_t 886 mul64_by_fraction(uint64_t a, uint64_t b, uint64_t c) 887 { 888 uint64_t acc, bh, bl; 889 int i, s, sa, sb; 890 891 /* 892 * Calculate (a * b) / c accurately enough without overflowing. c 893 * must be nonzero, and its top bit must be 0. a or b must be 894 * <= c, and the implementation is tuned for b <= c. 895 * 896 * The comments about times are for use in calcru1() with units of 897 * microseconds for 'a' and stathz ticks at 128 Hz for b and c. 898 * 899 * Let n be the number of top zero bits in c. Each iteration 900 * either returns, or reduces b by right shifting it by at least n. 901 * The number of iterations is at most 1 + 64 / n, and the error is 902 * at most the number of iterations. 903 * 904 * It is very unusual to need even 2 iterations. Previous 905 * implementations overflowed essentially by returning early in the 906 * first iteration, with n = 38 giving overflow at 105+ hours and 907 * n = 32 giving overlow at at 388+ days despite a more careful 908 * calculation. 388 days is a reasonable uptime, and the calculation 909 * needs to work for the uptime times the number of CPUs since 'a' 910 * is per-process. 911 */ 912 if (a >= (uint64_t)1 << 63) 913 return (0); /* Unsupported arg -- can't happen. */ 914 acc = 0; 915 for (i = 0; i < 128; i++) { 916 sa = flsll(a); 917 sb = flsll(b); 918 if (sa + sb <= 64) 919 /* Up to 105 hours on first iteration. */ 920 return (acc + (a * b) / c); 921 if (a >= c) { 922 /* 923 * This reduction is based on a = q * c + r, with the 924 * remainder r < c. 'a' may be large to start, and 925 * moving bits from b into 'a' at the end of the loop 926 * sets the top bit of 'a', so the reduction makes 927 * significant progress. 928 */ 929 acc += (a / c) * b; 930 a %= c; 931 sa = flsll(a); 932 if (sa + sb <= 64) 933 /* Up to 388 days on first iteration. */ 934 return (acc + (a * b) / c); 935 } 936 937 /* 938 * This step writes a * b as a * ((bh << s) + bl) = 939 * a * (bh << s) + a * bl = (a << s) * bh + a * bl. The 2 940 * additive terms are handled separately. Splitting in 941 * this way is linear except for rounding errors. 942 * 943 * s = 64 - sa is the maximum such that a << s fits in 64 944 * bits. Since a < c and c has at least 1 zero top bit, 945 * sa < 64 and s > 0. Thus this step makes progress by 946 * reducing b (it increases 'a', but taking remainders on 947 * the next iteration completes the reduction). 948 * 949 * Finally, the choice for s is just what is needed to keep 950 * a * bl from overflowing, so we don't need complications 951 * like a recursive call mul64_by_fraction(a, bl, c) to 952 * handle the second additive term. 953 */ 954 s = 64 - sa; 955 bh = b >> s; 956 bl = b - (bh << s); 957 acc += (a * bl) / c; 958 a <<= s; 959 b = bh; 960 } 961 return (0); /* Algorithm failure -- can't happen. */ 962 } 963 964 static void 965 calcru1(struct proc *p, struct rusage_ext *ruxp, struct timeval *up, 966 struct timeval *sp) 967 { 968 /* {user, system, interrupt, total} {ticks, usec}: */ 969 uint64_t ut, uu, st, su, it, tt, tu; 970 971 ut = ruxp->rux_uticks; 972 st = ruxp->rux_sticks; 973 it = ruxp->rux_iticks; 974 tt = ut + st + it; 975 if (tt == 0) { 976 /* Avoid divide by zero */ 977 st = 1; 978 tt = 1; 979 } 980 tu = cputick2usec(ruxp->rux_runtime); 981 if ((int64_t)tu < 0) { 982 /* XXX: this should be an assert /phk */ 983 printf("calcru: negative runtime of %jd usec for pid %d (%s)\n", 984 (intmax_t)tu, p->p_pid, p->p_comm); 985 tu = ruxp->rux_tu; 986 } 987 988 /* Subdivide tu. Avoid overflow in the multiplications. */ 989 if (__predict_true(tu <= ((uint64_t)1 << 38) && tt <= (1 << 26))) { 990 /* Up to 76 hours when stathz is 128. */ 991 uu = (tu * ut) / tt; 992 su = (tu * st) / tt; 993 } else { 994 uu = mul64_by_fraction(tu, ut, tt); 995 su = mul64_by_fraction(tu, st, tt); 996 } 997 998 if (tu >= ruxp->rux_tu) { 999 /* 1000 * The normal case, time increased. 1001 * Enforce monotonicity of bucketed numbers. 1002 */ 1003 if (uu < ruxp->rux_uu) 1004 uu = ruxp->rux_uu; 1005 if (su < ruxp->rux_su) 1006 su = ruxp->rux_su; 1007 } else if (tu + 3 > ruxp->rux_tu || 101 * tu > 100 * ruxp->rux_tu) { 1008 /* 1009 * When we calibrate the cputicker, it is not uncommon to 1010 * see the presumably fixed frequency increase slightly over 1011 * time as a result of thermal stabilization and NTP 1012 * discipline (of the reference clock). We therefore ignore 1013 * a bit of backwards slop because we expect to catch up 1014 * shortly. We use a 3 microsecond limit to catch low 1015 * counts and a 1% limit for high counts. 1016 */ 1017 uu = ruxp->rux_uu; 1018 su = ruxp->rux_su; 1019 tu = ruxp->rux_tu; 1020 } else { /* tu < ruxp->rux_tu */ 1021 /* 1022 * What happened here was likely that a laptop, which ran at 1023 * a reduced clock frequency at boot, kicked into high gear. 1024 * The wisdom of spamming this message in that case is 1025 * dubious, but it might also be indicative of something 1026 * serious, so lets keep it and hope laptops can be made 1027 * more truthful about their CPU speed via ACPI. 1028 */ 1029 printf("calcru: runtime went backwards from %ju usec " 1030 "to %ju usec for pid %d (%s)\n", 1031 (uintmax_t)ruxp->rux_tu, (uintmax_t)tu, 1032 p->p_pid, p->p_comm); 1033 } 1034 1035 ruxp->rux_uu = uu; 1036 ruxp->rux_su = su; 1037 ruxp->rux_tu = tu; 1038 1039 up->tv_sec = uu / 1000000; 1040 up->tv_usec = uu % 1000000; 1041 sp->tv_sec = su / 1000000; 1042 sp->tv_usec = su % 1000000; 1043 } 1044 1045 #ifndef _SYS_SYSPROTO_H_ 1046 struct getrusage_args { 1047 int who; 1048 struct rusage *rusage; 1049 }; 1050 #endif 1051 int 1052 sys_getrusage(struct thread *td, struct getrusage_args *uap) 1053 { 1054 struct rusage ru; 1055 int error; 1056 1057 error = kern_getrusage(td, uap->who, &ru); 1058 if (error == 0) 1059 error = copyout(&ru, uap->rusage, sizeof(struct rusage)); 1060 return (error); 1061 } 1062 1063 int 1064 kern_getrusage(struct thread *td, int who, struct rusage *rup) 1065 { 1066 struct proc *p; 1067 int error; 1068 1069 error = 0; 1070 p = td->td_proc; 1071 PROC_LOCK(p); 1072 switch (who) { 1073 case RUSAGE_SELF: 1074 rufetchcalc(p, rup, &rup->ru_utime, 1075 &rup->ru_stime); 1076 break; 1077 1078 case RUSAGE_CHILDREN: 1079 *rup = p->p_stats->p_cru; 1080 calccru(p, &rup->ru_utime, &rup->ru_stime); 1081 break; 1082 1083 case RUSAGE_THREAD: 1084 PROC_STATLOCK(p); 1085 thread_lock(td); 1086 rufetchtd(td, rup); 1087 thread_unlock(td); 1088 PROC_STATUNLOCK(p); 1089 break; 1090 1091 default: 1092 error = EINVAL; 1093 } 1094 PROC_UNLOCK(p); 1095 return (error); 1096 } 1097 1098 void 1099 rucollect(struct rusage *ru, struct rusage *ru2) 1100 { 1101 long *ip, *ip2; 1102 int i; 1103 1104 if (ru->ru_maxrss < ru2->ru_maxrss) 1105 ru->ru_maxrss = ru2->ru_maxrss; 1106 ip = &ru->ru_first; 1107 ip2 = &ru2->ru_first; 1108 for (i = &ru->ru_last - &ru->ru_first; i >= 0; i--) 1109 *ip++ += *ip2++; 1110 } 1111 1112 void 1113 ruadd(struct rusage *ru, struct rusage_ext *rux, struct rusage *ru2, 1114 struct rusage_ext *rux2) 1115 { 1116 1117 rux->rux_runtime += rux2->rux_runtime; 1118 rux->rux_uticks += rux2->rux_uticks; 1119 rux->rux_sticks += rux2->rux_sticks; 1120 rux->rux_iticks += rux2->rux_iticks; 1121 rux->rux_uu += rux2->rux_uu; 1122 rux->rux_su += rux2->rux_su; 1123 rux->rux_tu += rux2->rux_tu; 1124 rucollect(ru, ru2); 1125 } 1126 1127 /* 1128 * Aggregate tick counts into the proc's rusage_ext. 1129 */ 1130 static void 1131 ruxagg_ext_locked(struct rusage_ext *rux, struct thread *td) 1132 { 1133 1134 rux->rux_runtime += td->td_incruntime; 1135 rux->rux_uticks += td->td_uticks; 1136 rux->rux_sticks += td->td_sticks; 1137 rux->rux_iticks += td->td_iticks; 1138 } 1139 1140 void 1141 ruxagg_locked(struct proc *p, struct thread *td) 1142 { 1143 THREAD_LOCK_ASSERT(td, MA_OWNED); 1144 PROC_STATLOCK_ASSERT(td->td_proc, MA_OWNED); 1145 1146 ruxagg_ext_locked(&p->p_rux, td); 1147 ruxagg_ext_locked(&td->td_rux, td); 1148 td->td_incruntime = 0; 1149 td->td_uticks = 0; 1150 td->td_iticks = 0; 1151 td->td_sticks = 0; 1152 } 1153 1154 void 1155 ruxagg(struct proc *p, struct thread *td) 1156 { 1157 1158 thread_lock(td); 1159 ruxagg_locked(p, td); 1160 thread_unlock(td); 1161 } 1162 1163 /* 1164 * Update the rusage_ext structure and fetch a valid aggregate rusage 1165 * for proc p if storage for one is supplied. 1166 */ 1167 void 1168 rufetch(struct proc *p, struct rusage *ru) 1169 { 1170 struct thread *td; 1171 1172 PROC_STATLOCK_ASSERT(p, MA_OWNED); 1173 1174 *ru = p->p_ru; 1175 if (p->p_numthreads > 0) { 1176 FOREACH_THREAD_IN_PROC(p, td) { 1177 ruxagg(p, td); 1178 rucollect(ru, &td->td_ru); 1179 } 1180 } 1181 } 1182 1183 /* 1184 * Atomically perform a rufetch and a calcru together. 1185 * Consumers, can safely assume the calcru is executed only once 1186 * rufetch is completed. 1187 */ 1188 void 1189 rufetchcalc(struct proc *p, struct rusage *ru, struct timeval *up, 1190 struct timeval *sp) 1191 { 1192 1193 PROC_STATLOCK(p); 1194 rufetch(p, ru); 1195 calcru(p, up, sp); 1196 PROC_STATUNLOCK(p); 1197 } 1198 1199 /* 1200 * Allocate a new resource limits structure and initialize its 1201 * reference count and mutex pointer. 1202 */ 1203 struct plimit * 1204 lim_alloc() 1205 { 1206 struct plimit *limp; 1207 1208 limp = malloc(sizeof(struct plimit), M_PLIMIT, M_WAITOK); 1209 refcount_init(&limp->pl_refcnt, 1); 1210 return (limp); 1211 } 1212 1213 struct plimit * 1214 lim_hold(struct plimit *limp) 1215 { 1216 1217 refcount_acquire(&limp->pl_refcnt); 1218 return (limp); 1219 } 1220 1221 void 1222 lim_fork(struct proc *p1, struct proc *p2) 1223 { 1224 1225 PROC_LOCK_ASSERT(p1, MA_OWNED); 1226 PROC_LOCK_ASSERT(p2, MA_OWNED); 1227 1228 p2->p_limit = lim_hold(p1->p_limit); 1229 callout_init_mtx(&p2->p_limco, &p2->p_mtx, 0); 1230 if (p1->p_cpulimit != RLIM_INFINITY) 1231 callout_reset_sbt(&p2->p_limco, SBT_1S, 0, 1232 lim_cb, p2, C_PREL(1)); 1233 } 1234 1235 void 1236 lim_free(struct plimit *limp) 1237 { 1238 1239 if (refcount_release(&limp->pl_refcnt)) 1240 free((void *)limp, M_PLIMIT); 1241 } 1242 1243 void 1244 lim_freen(struct plimit *limp, int n) 1245 { 1246 1247 if (refcount_releasen(&limp->pl_refcnt, n)) 1248 free((void *)limp, M_PLIMIT); 1249 } 1250 1251 /* 1252 * Make a copy of the plimit structure. 1253 * We share these structures copy-on-write after fork. 1254 */ 1255 void 1256 lim_copy(struct plimit *dst, struct plimit *src) 1257 { 1258 1259 KASSERT(dst->pl_refcnt <= 1, ("lim_copy to shared limit")); 1260 bcopy(src->pl_rlimit, dst->pl_rlimit, sizeof(src->pl_rlimit)); 1261 } 1262 1263 /* 1264 * Return the hard limit for a particular system resource. The 1265 * which parameter specifies the index into the rlimit array. 1266 */ 1267 rlim_t 1268 lim_max(struct thread *td, int which) 1269 { 1270 struct rlimit rl; 1271 1272 lim_rlimit(td, which, &rl); 1273 return (rl.rlim_max); 1274 } 1275 1276 rlim_t 1277 lim_max_proc(struct proc *p, int which) 1278 { 1279 struct rlimit rl; 1280 1281 lim_rlimit_proc(p, which, &rl); 1282 return (rl.rlim_max); 1283 } 1284 1285 /* 1286 * Return the current (soft) limit for a particular system resource. 1287 * The which parameter which specifies the index into the rlimit array 1288 */ 1289 rlim_t 1290 (lim_cur)(struct thread *td, int which) 1291 { 1292 struct rlimit rl; 1293 1294 lim_rlimit(td, which, &rl); 1295 return (rl.rlim_cur); 1296 } 1297 1298 rlim_t 1299 lim_cur_proc(struct proc *p, int which) 1300 { 1301 struct rlimit rl; 1302 1303 lim_rlimit_proc(p, which, &rl); 1304 return (rl.rlim_cur); 1305 } 1306 1307 /* 1308 * Return a copy of the entire rlimit structure for the system limit 1309 * specified by 'which' in the rlimit structure pointed to by 'rlp'. 1310 */ 1311 void 1312 lim_rlimit(struct thread *td, int which, struct rlimit *rlp) 1313 { 1314 struct proc *p = td->td_proc; 1315 1316 MPASS(td == curthread); 1317 KASSERT(which >= 0 && which < RLIM_NLIMITS, 1318 ("request for invalid resource limit")); 1319 *rlp = td->td_limit->pl_rlimit[which]; 1320 if (p->p_sysent->sv_fixlimit != NULL) 1321 p->p_sysent->sv_fixlimit(rlp, which); 1322 } 1323 1324 void 1325 lim_rlimit_proc(struct proc *p, int which, struct rlimit *rlp) 1326 { 1327 1328 PROC_LOCK_ASSERT(p, MA_OWNED); 1329 KASSERT(which >= 0 && which < RLIM_NLIMITS, 1330 ("request for invalid resource limit")); 1331 *rlp = p->p_limit->pl_rlimit[which]; 1332 if (p->p_sysent->sv_fixlimit != NULL) 1333 p->p_sysent->sv_fixlimit(rlp, which); 1334 } 1335 1336 void 1337 uihashinit() 1338 { 1339 1340 uihashtbl = hashinit(maxproc / 16, M_UIDINFO, &uihash); 1341 rw_init(&uihashtbl_lock, "uidinfo hash"); 1342 } 1343 1344 /* 1345 * Look up a uidinfo struct for the parameter uid. 1346 * uihashtbl_lock must be locked. 1347 * Increase refcount on uidinfo struct returned. 1348 */ 1349 static struct uidinfo * 1350 uilookup(uid_t uid) 1351 { 1352 struct uihashhead *uipp; 1353 struct uidinfo *uip; 1354 1355 rw_assert(&uihashtbl_lock, RA_LOCKED); 1356 uipp = UIHASH(uid); 1357 LIST_FOREACH(uip, uipp, ui_hash) 1358 if (uip->ui_uid == uid) { 1359 uihold(uip); 1360 break; 1361 } 1362 1363 return (uip); 1364 } 1365 1366 /* 1367 * Find or allocate a struct uidinfo for a particular uid. 1368 * Returns with uidinfo struct referenced. 1369 * uifree() should be called on a struct uidinfo when released. 1370 */ 1371 struct uidinfo * 1372 uifind(uid_t uid) 1373 { 1374 struct uidinfo *new_uip, *uip; 1375 struct ucred *cred; 1376 1377 cred = curthread->td_ucred; 1378 if (cred->cr_uidinfo->ui_uid == uid) { 1379 uip = cred->cr_uidinfo; 1380 uihold(uip); 1381 return (uip); 1382 } else if (cred->cr_ruidinfo->ui_uid == uid) { 1383 uip = cred->cr_ruidinfo; 1384 uihold(uip); 1385 return (uip); 1386 } 1387 1388 rw_rlock(&uihashtbl_lock); 1389 uip = uilookup(uid); 1390 rw_runlock(&uihashtbl_lock); 1391 if (uip != NULL) 1392 return (uip); 1393 1394 new_uip = malloc(sizeof(*new_uip), M_UIDINFO, M_WAITOK | M_ZERO); 1395 racct_create(&new_uip->ui_racct); 1396 refcount_init(&new_uip->ui_ref, 1); 1397 new_uip->ui_uid = uid; 1398 1399 rw_wlock(&uihashtbl_lock); 1400 /* 1401 * There's a chance someone created our uidinfo while we 1402 * were in malloc and not holding the lock, so we have to 1403 * make sure we don't insert a duplicate uidinfo. 1404 */ 1405 if ((uip = uilookup(uid)) == NULL) { 1406 LIST_INSERT_HEAD(UIHASH(uid), new_uip, ui_hash); 1407 rw_wunlock(&uihashtbl_lock); 1408 uip = new_uip; 1409 } else { 1410 rw_wunlock(&uihashtbl_lock); 1411 racct_destroy(&new_uip->ui_racct); 1412 free(new_uip, M_UIDINFO); 1413 } 1414 return (uip); 1415 } 1416 1417 /* 1418 * Place another refcount on a uidinfo struct. 1419 */ 1420 void 1421 uihold(struct uidinfo *uip) 1422 { 1423 1424 refcount_acquire(&uip->ui_ref); 1425 } 1426 1427 /*- 1428 * Since uidinfo structs have a long lifetime, we use an 1429 * opportunistic refcounting scheme to avoid locking the lookup hash 1430 * for each release. 1431 * 1432 * If the refcount hits 0, we need to free the structure, 1433 * which means we need to lock the hash. 1434 * Optimal case: 1435 * After locking the struct and lowering the refcount, if we find 1436 * that we don't need to free, simply unlock and return. 1437 * Suboptimal case: 1438 * If refcount lowering results in need to free, bump the count 1439 * back up, lose the lock and acquire the locks in the proper 1440 * order to try again. 1441 */ 1442 void 1443 uifree(struct uidinfo *uip) 1444 { 1445 1446 if (refcount_release_if_not_last(&uip->ui_ref)) 1447 return; 1448 1449 rw_wlock(&uihashtbl_lock); 1450 if (refcount_release(&uip->ui_ref) == 0) { 1451 rw_wunlock(&uihashtbl_lock); 1452 return; 1453 } 1454 1455 racct_destroy(&uip->ui_racct); 1456 LIST_REMOVE(uip, ui_hash); 1457 rw_wunlock(&uihashtbl_lock); 1458 1459 if (uip->ui_sbsize != 0) 1460 printf("freeing uidinfo: uid = %d, sbsize = %ld\n", 1461 uip->ui_uid, uip->ui_sbsize); 1462 if (uip->ui_proccnt != 0) 1463 printf("freeing uidinfo: uid = %d, proccnt = %ld\n", 1464 uip->ui_uid, uip->ui_proccnt); 1465 if (uip->ui_vmsize != 0) 1466 printf("freeing uidinfo: uid = %d, swapuse = %lld\n", 1467 uip->ui_uid, (unsigned long long)uip->ui_vmsize); 1468 free(uip, M_UIDINFO); 1469 } 1470 1471 #ifdef RACCT 1472 void 1473 ui_racct_foreach(void (*callback)(struct racct *racct, 1474 void *arg2, void *arg3), void (*pre)(void), void (*post)(void), 1475 void *arg2, void *arg3) 1476 { 1477 struct uidinfo *uip; 1478 struct uihashhead *uih; 1479 1480 rw_rlock(&uihashtbl_lock); 1481 if (pre != NULL) 1482 (pre)(); 1483 for (uih = &uihashtbl[uihash]; uih >= uihashtbl; uih--) { 1484 LIST_FOREACH(uip, uih, ui_hash) { 1485 (callback)(uip->ui_racct, arg2, arg3); 1486 } 1487 } 1488 if (post != NULL) 1489 (post)(); 1490 rw_runlock(&uihashtbl_lock); 1491 } 1492 #endif 1493 1494 static inline int 1495 chglimit(struct uidinfo *uip, long *limit, int diff, rlim_t max, const char *name) 1496 { 1497 long new; 1498 1499 /* Don't allow them to exceed max, but allow subtraction. */ 1500 new = atomic_fetchadd_long(limit, (long)diff) + diff; 1501 if (diff > 0 && max != 0) { 1502 if (new < 0 || new > max) { 1503 atomic_subtract_long(limit, (long)diff); 1504 return (0); 1505 } 1506 } else if (new < 0) 1507 printf("negative %s for uid = %d\n", name, uip->ui_uid); 1508 return (1); 1509 } 1510 1511 /* 1512 * Change the count associated with number of processes 1513 * a given user is using. When 'max' is 0, don't enforce a limit 1514 */ 1515 int 1516 chgproccnt(struct uidinfo *uip, int diff, rlim_t max) 1517 { 1518 1519 return (chglimit(uip, &uip->ui_proccnt, diff, max, "proccnt")); 1520 } 1521 1522 /* 1523 * Change the total socket buffer size a user has used. 1524 */ 1525 int 1526 chgsbsize(struct uidinfo *uip, u_int *hiwat, u_int to, rlim_t max) 1527 { 1528 int diff, rv; 1529 1530 diff = to - *hiwat; 1531 if (diff > 0 && max == 0) { 1532 rv = 0; 1533 } else { 1534 rv = chglimit(uip, &uip->ui_sbsize, diff, max, "sbsize"); 1535 if (rv != 0) 1536 *hiwat = to; 1537 } 1538 return (rv); 1539 } 1540 1541 /* 1542 * Change the count associated with number of pseudo-terminals 1543 * a given user is using. When 'max' is 0, don't enforce a limit 1544 */ 1545 int 1546 chgptscnt(struct uidinfo *uip, int diff, rlim_t max) 1547 { 1548 1549 return (chglimit(uip, &uip->ui_ptscnt, diff, max, "ptscnt")); 1550 } 1551 1552 int 1553 chgkqcnt(struct uidinfo *uip, int diff, rlim_t max) 1554 { 1555 1556 return (chglimit(uip, &uip->ui_kqcnt, diff, max, "kqcnt")); 1557 } 1558 1559 int 1560 chgumtxcnt(struct uidinfo *uip, int diff, rlim_t max) 1561 { 1562 1563 return (chglimit(uip, &uip->ui_umtxcnt, diff, max, "umtxcnt")); 1564 } 1565