1 /*- 2 * Copyright (c) 1982, 1986, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)kern_resource.c 8.5 (Berkeley) 1/21/94 39 * $FreeBSD: src/sys/kern/kern_resource.c,v 1.55.2.5 2001/11/03 01:41:08 ps Exp $ 40 * $DragonFly: src/sys/kern/kern_resource.c,v 1.35 2008/05/27 05:25:34 dillon Exp $ 41 */ 42 43 #include "opt_compat.h" 44 45 #include <sys/param.h> 46 #include <sys/systm.h> 47 #include <sys/sysproto.h> 48 #include <sys/file.h> 49 #include <sys/kern_syscall.h> 50 #include <sys/kernel.h> 51 #include <sys/resourcevar.h> 52 #include <sys/malloc.h> 53 #include <sys/proc.h> 54 #include <sys/priv.h> 55 #include <sys/time.h> 56 #include <sys/lockf.h> 57 58 #include <vm/vm.h> 59 #include <vm/vm_param.h> 60 #include <sys/lock.h> 61 #include <vm/pmap.h> 62 #include <vm/vm_map.h> 63 64 #include <sys/thread2.h> 65 #include <sys/spinlock2.h> 66 67 static int donice (struct proc *chgp, int n); 68 static int doionice (struct proc *chgp, int n); 69 70 static MALLOC_DEFINE(M_UIDINFO, "uidinfo", "uidinfo structures"); 71 #define UIHASH(uid) (&uihashtbl[(uid) & uihash]) 72 static struct spinlock uihash_lock; 73 static LIST_HEAD(uihashhead, uidinfo) *uihashtbl; 74 static u_long uihash; /* size of hash table - 1 */ 75 76 static struct uidinfo *uicreate (uid_t uid); 77 static struct uidinfo *uilookup (uid_t uid); 78 79 /* 80 * Resource controls and accounting. 81 */ 82 83 struct getpriority_info { 84 int low; 85 int who; 86 }; 87 88 static int getpriority_callback(struct proc *p, void *data); 89 90 /* 91 * MPALMOSTSAFE 92 */ 93 int 94 sys_getpriority(struct getpriority_args *uap) 95 { 96 struct getpriority_info info; 97 struct proc *curp = curproc; 98 struct proc *p; 99 int low = PRIO_MAX + 1; 100 int error; 101 102 switch (uap->which) { 103 case PRIO_PROCESS: 104 if (uap->who == 0) { 105 p = curp; 106 PHOLD(p); 107 } else { 108 p = pfind(uap->who); 109 } 110 if (p) { 111 if (PRISON_CHECK(curp->p_ucred, p->p_ucred)) { 112 low = p->p_nice; 113 } 114 PRELE(p); 115 } 116 break; 117 118 case PRIO_PGRP: 119 { 120 struct pgrp *pg; 121 122 if (uap->who == 0) { 123 pg = curp->p_pgrp; 124 pgref(pg); 125 } else if ((pg = pgfind(uap->who)) == NULL) { 126 break; 127 } /* else ref held from pgfind */ 128 129 LIST_FOREACH(p, &pg->pg_members, p_pglist) { 130 if (PRISON_CHECK(curp->p_ucred, p->p_ucred) && 131 p->p_nice < low) { 132 low = p->p_nice; 133 } 134 } 135 pgrel(pg); 136 break; 137 } 138 case PRIO_USER: 139 if (uap->who == 0) 140 uap->who = curp->p_ucred->cr_uid; 141 info.low = low; 142 info.who = uap->who; 143 allproc_scan(getpriority_callback, &info); 144 low = info.low; 145 break; 146 147 default: 148 error = EINVAL; 149 goto done; 150 } 151 if (low == PRIO_MAX + 1) { 152 error = ESRCH; 153 goto done; 154 } 155 uap->sysmsg_result = low; 156 error = 0; 157 done: 158 return (error); 159 } 160 161 /* 162 * Figure out the current lowest nice priority for processes owned 163 * by the specified user. 164 */ 165 static 166 int 167 getpriority_callback(struct proc *p, void *data) 168 { 169 struct getpriority_info *info = data; 170 171 if (PRISON_CHECK(curproc->p_ucred, p->p_ucred) && 172 p->p_ucred->cr_uid == info->who && 173 p->p_nice < info->low) { 174 info->low = p->p_nice; 175 } 176 return(0); 177 } 178 179 struct setpriority_info { 180 int prio; 181 int who; 182 int error; 183 int found; 184 }; 185 186 static int setpriority_callback(struct proc *p, void *data); 187 188 /* 189 * MPALMOSTSAFE 190 */ 191 int 192 sys_setpriority(struct setpriority_args *uap) 193 { 194 struct setpriority_info info; 195 struct proc *curp = curproc; 196 struct proc *p; 197 int found = 0, error = 0; 198 199 lwkt_gettoken(&proc_token); 200 201 switch (uap->which) { 202 case PRIO_PROCESS: 203 if (uap->who == 0) { 204 p = curp; 205 PHOLD(p); 206 } else { 207 p = pfind(uap->who); 208 } 209 if (p) { 210 if (PRISON_CHECK(curp->p_ucred, p->p_ucred)) { 211 error = donice(p, uap->prio); 212 found++; 213 } 214 PRELE(p); 215 } 216 break; 217 218 case PRIO_PGRP: 219 { 220 struct pgrp *pg; 221 222 if (uap->who == 0) { 223 pg = curp->p_pgrp; 224 pgref(pg); 225 } else if ((pg = pgfind(uap->who)) == NULL) { 226 break; 227 } /* else ref held from pgfind */ 228 229 LIST_FOREACH(p, &pg->pg_members, p_pglist) { 230 if (PRISON_CHECK(curp->p_ucred, p->p_ucred)) { 231 error = donice(p, uap->prio); 232 found++; 233 } 234 } 235 pgrel(pg); 236 break; 237 } 238 case PRIO_USER: 239 if (uap->who == 0) 240 uap->who = curp->p_ucred->cr_uid; 241 info.prio = uap->prio; 242 info.who = uap->who; 243 info.error = 0; 244 info.found = 0; 245 allproc_scan(setpriority_callback, &info); 246 error = info.error; 247 found = info.found; 248 break; 249 250 default: 251 error = EINVAL; 252 found = 1; 253 break; 254 } 255 256 lwkt_reltoken(&proc_token); 257 258 if (found == 0) 259 error = ESRCH; 260 return (error); 261 } 262 263 static 264 int 265 setpriority_callback(struct proc *p, void *data) 266 { 267 struct setpriority_info *info = data; 268 int error; 269 270 if (p->p_ucred->cr_uid == info->who && 271 PRISON_CHECK(curproc->p_ucred, p->p_ucred)) { 272 error = donice(p, info->prio); 273 if (error) 274 info->error = error; 275 ++info->found; 276 } 277 return(0); 278 } 279 280 static int 281 donice(struct proc *chgp, int n) 282 { 283 struct proc *curp = curproc; 284 struct ucred *cr = curp->p_ucred; 285 struct lwp *lp; 286 287 if (cr->cr_uid && cr->cr_ruid && 288 cr->cr_uid != chgp->p_ucred->cr_uid && 289 cr->cr_ruid != chgp->p_ucred->cr_uid) 290 return (EPERM); 291 if (n > PRIO_MAX) 292 n = PRIO_MAX; 293 if (n < PRIO_MIN) 294 n = PRIO_MIN; 295 if (n < chgp->p_nice && priv_check_cred(cr, PRIV_SCHED_SETPRIORITY, 0)) 296 return (EACCES); 297 chgp->p_nice = n; 298 FOREACH_LWP_IN_PROC(lp, chgp) 299 chgp->p_usched->resetpriority(lp); 300 return (0); 301 } 302 303 304 struct ioprio_get_info { 305 int high; 306 int who; 307 }; 308 309 static int ioprio_get_callback(struct proc *p, void *data); 310 311 /* 312 * MPALMOSTSAFE 313 */ 314 int 315 sys_ioprio_get(struct ioprio_get_args *uap) 316 { 317 struct ioprio_get_info info; 318 struct proc *curp = curproc; 319 struct proc *p; 320 int high = IOPRIO_MIN-2; 321 int error; 322 323 lwkt_gettoken(&proc_token); 324 325 switch (uap->which) { 326 case PRIO_PROCESS: 327 if (uap->who == 0) { 328 p = curp; 329 PHOLD(p); 330 } else { 331 p = pfind(uap->who); 332 } 333 if (p) { 334 if (PRISON_CHECK(curp->p_ucred, p->p_ucred)) 335 high = p->p_ionice; 336 PRELE(p); 337 } 338 break; 339 340 case PRIO_PGRP: 341 { 342 struct pgrp *pg; 343 344 if (uap->who == 0) { 345 pg = curp->p_pgrp; 346 pgref(pg); 347 } else if ((pg = pgfind(uap->who)) == NULL) { 348 break; 349 } /* else ref held from pgfind */ 350 351 LIST_FOREACH(p, &pg->pg_members, p_pglist) { 352 if (PRISON_CHECK(curp->p_ucred, p->p_ucred) && 353 p->p_nice > high) 354 high = p->p_ionice; 355 } 356 pgrel(pg); 357 break; 358 } 359 case PRIO_USER: 360 if (uap->who == 0) 361 uap->who = curp->p_ucred->cr_uid; 362 info.high = high; 363 info.who = uap->who; 364 allproc_scan(ioprio_get_callback, &info); 365 high = info.high; 366 break; 367 368 default: 369 error = EINVAL; 370 goto done; 371 } 372 if (high == IOPRIO_MIN-2) { 373 error = ESRCH; 374 goto done; 375 } 376 uap->sysmsg_result = high; 377 error = 0; 378 done: 379 lwkt_reltoken(&proc_token); 380 381 return (error); 382 } 383 384 /* 385 * Figure out the current lowest nice priority for processes owned 386 * by the specified user. 387 */ 388 static 389 int 390 ioprio_get_callback(struct proc *p, void *data) 391 { 392 struct ioprio_get_info *info = data; 393 394 if (PRISON_CHECK(curproc->p_ucred, p->p_ucred) && 395 p->p_ucred->cr_uid == info->who && 396 p->p_ionice > info->high) { 397 info->high = p->p_ionice; 398 } 399 return(0); 400 } 401 402 403 struct ioprio_set_info { 404 int prio; 405 int who; 406 int error; 407 int found; 408 }; 409 410 static int ioprio_set_callback(struct proc *p, void *data); 411 412 /* 413 * MPALMOSTSAFE 414 */ 415 int 416 sys_ioprio_set(struct ioprio_set_args *uap) 417 { 418 struct ioprio_set_info info; 419 struct proc *curp = curproc; 420 struct proc *p; 421 int found = 0, error = 0; 422 423 lwkt_gettoken(&proc_token); 424 425 switch (uap->which) { 426 case PRIO_PROCESS: 427 if (uap->who == 0) { 428 p = curp; 429 PHOLD(p); 430 } else { 431 p = pfind(uap->who); 432 } 433 if (p) { 434 if (PRISON_CHECK(curp->p_ucred, p->p_ucred)) { 435 error = doionice(p, uap->prio); 436 found++; 437 } 438 PRELE(p); 439 } 440 break; 441 442 case PRIO_PGRP: 443 { 444 struct pgrp *pg; 445 446 if (uap->who == 0) { 447 pg = curp->p_pgrp; 448 pgref(pg); 449 } else if ((pg = pgfind(uap->who)) == NULL) { 450 break; 451 } /* else ref held from pgfind */ 452 453 LIST_FOREACH(p, &pg->pg_members, p_pglist) { 454 if (PRISON_CHECK(curp->p_ucred, p->p_ucred)) { 455 error = doionice(p, uap->prio); 456 found++; 457 } 458 } 459 pgrel(pg); 460 break; 461 } 462 case PRIO_USER: 463 if (uap->who == 0) 464 uap->who = curp->p_ucred->cr_uid; 465 info.prio = uap->prio; 466 info.who = uap->who; 467 info.error = 0; 468 info.found = 0; 469 allproc_scan(ioprio_set_callback, &info); 470 error = info.error; 471 found = info.found; 472 break; 473 474 default: 475 error = EINVAL; 476 found = 1; 477 break; 478 } 479 480 lwkt_reltoken(&proc_token); 481 482 if (found == 0) 483 error = ESRCH; 484 return (error); 485 } 486 487 static 488 int 489 ioprio_set_callback(struct proc *p, void *data) 490 { 491 struct ioprio_set_info *info = data; 492 int error; 493 494 if (p->p_ucred->cr_uid == info->who && 495 PRISON_CHECK(curproc->p_ucred, p->p_ucred)) { 496 error = doionice(p, info->prio); 497 if (error) 498 info->error = error; 499 ++info->found; 500 } 501 return(0); 502 } 503 504 int 505 doionice(struct proc *chgp, int n) 506 { 507 struct proc *curp = curproc; 508 struct ucred *cr = curp->p_ucred; 509 510 if (cr->cr_uid && cr->cr_ruid && 511 cr->cr_uid != chgp->p_ucred->cr_uid && 512 cr->cr_ruid != chgp->p_ucred->cr_uid) 513 return (EPERM); 514 if (n > IOPRIO_MAX) 515 n = IOPRIO_MAX; 516 if (n < IOPRIO_MIN) 517 n = IOPRIO_MIN; 518 if (n < chgp->p_ionice && priv_check_cred(cr, PRIV_SCHED_SETPRIORITY, 0)) 519 return (EACCES); 520 chgp->p_ionice = n; 521 522 return (0); 523 524 } 525 526 /* 527 * MPALMOSTSAFE 528 */ 529 int 530 sys_lwp_rtprio(struct lwp_rtprio_args *uap) 531 { 532 struct proc *p; 533 struct lwp *lp; 534 struct rtprio rtp; 535 struct ucred *cr = curthread->td_ucred; 536 int error; 537 538 error = copyin(uap->rtp, &rtp, sizeof(struct rtprio)); 539 if (error) 540 return error; 541 if (uap->pid < 0) 542 return EINVAL; 543 544 lwkt_gettoken(&proc_token); 545 546 if (uap->pid == 0) { 547 p = curproc; 548 PHOLD(p); 549 } else { 550 p = pfind(uap->pid); 551 } 552 553 if (p == NULL) { 554 error = ESRCH; 555 goto done; 556 } 557 558 if (uap->tid < -1) { 559 error = EINVAL; 560 goto done; 561 } 562 if (uap->tid == -1) { 563 /* 564 * sadly, tid can be 0 so we can't use 0 here 565 * like sys_rtprio() 566 */ 567 lp = curthread->td_lwp; 568 } else { 569 lp = lwp_rb_tree_RB_LOOKUP(&p->p_lwp_tree, uap->tid); 570 if (lp == NULL) { 571 error = ESRCH; 572 goto done; 573 } 574 } 575 576 switch (uap->function) { 577 case RTP_LOOKUP: 578 error = copyout(&lp->lwp_rtprio, uap->rtp, 579 sizeof(struct rtprio)); 580 break; 581 case RTP_SET: 582 if (cr->cr_uid && cr->cr_ruid && 583 cr->cr_uid != p->p_ucred->cr_uid && 584 cr->cr_ruid != p->p_ucred->cr_uid) { 585 error = EPERM; 586 break; 587 } 588 /* disallow setting rtprio in most cases if not superuser */ 589 if (priv_check_cred(cr, PRIV_SCHED_RTPRIO, 0)) { 590 /* can't set someone else's */ 591 if (uap->pid) { /* XXX */ 592 error = EPERM; 593 break; 594 } 595 /* can't set realtime priority */ 596 /* 597 * Realtime priority has to be restricted for reasons which should be 598 * obvious. However, for idle priority, there is a potential for 599 * system deadlock if an idleprio process gains a lock on a resource 600 * that other processes need (and the idleprio process can't run 601 * due to a CPU-bound normal process). Fix me! XXX 602 */ 603 if (RTP_PRIO_IS_REALTIME(rtp.type)) { 604 error = EPERM; 605 break; 606 } 607 } 608 switch (rtp.type) { 609 #ifdef RTP_PRIO_FIFO 610 case RTP_PRIO_FIFO: 611 #endif 612 case RTP_PRIO_REALTIME: 613 case RTP_PRIO_NORMAL: 614 case RTP_PRIO_IDLE: 615 if (rtp.prio > RTP_PRIO_MAX) { 616 error = EINVAL; 617 } else { 618 lp->lwp_rtprio = rtp; 619 error = 0; 620 } 621 break; 622 default: 623 error = EINVAL; 624 break; 625 } 626 break; 627 default: 628 error = EINVAL; 629 break; 630 } 631 632 done: 633 if (p) 634 PRELE(p); 635 lwkt_reltoken(&proc_token); 636 637 return (error); 638 } 639 640 /* 641 * Set realtime priority 642 * 643 * MPALMOSTSAFE 644 */ 645 int 646 sys_rtprio(struct rtprio_args *uap) 647 { 648 struct proc *p; 649 struct lwp *lp; 650 struct ucred *cr = curthread->td_ucred; 651 struct rtprio rtp; 652 int error; 653 654 error = copyin(uap->rtp, &rtp, sizeof(struct rtprio)); 655 if (error) 656 return (error); 657 658 lwkt_gettoken(&proc_token); 659 660 if (uap->pid == 0) { 661 p = curproc; 662 PHOLD(p); 663 } else { 664 p = pfind(uap->pid); 665 } 666 667 if (p == NULL) { 668 error = ESRCH; 669 goto done; 670 } 671 672 /* XXX lwp */ 673 lp = FIRST_LWP_IN_PROC(p); 674 switch (uap->function) { 675 case RTP_LOOKUP: 676 error = copyout(&lp->lwp_rtprio, uap->rtp, 677 sizeof(struct rtprio)); 678 break; 679 case RTP_SET: 680 if (cr->cr_uid && cr->cr_ruid && 681 cr->cr_uid != p->p_ucred->cr_uid && 682 cr->cr_ruid != p->p_ucred->cr_uid) { 683 error = EPERM; 684 break; 685 } 686 /* disallow setting rtprio in most cases if not superuser */ 687 if (priv_check_cred(cr, PRIV_SCHED_RTPRIO, 0)) { 688 /* can't set someone else's */ 689 if (uap->pid) { 690 error = EPERM; 691 break; 692 } 693 /* can't set realtime priority */ 694 /* 695 * Realtime priority has to be restricted for reasons which should be 696 * obvious. However, for idle priority, there is a potential for 697 * system deadlock if an idleprio process gains a lock on a resource 698 * that other processes need (and the idleprio process can't run 699 * due to a CPU-bound normal process). Fix me! XXX 700 */ 701 if (RTP_PRIO_IS_REALTIME(rtp.type)) { 702 error = EPERM; 703 break; 704 } 705 } 706 switch (rtp.type) { 707 #ifdef RTP_PRIO_FIFO 708 case RTP_PRIO_FIFO: 709 #endif 710 case RTP_PRIO_REALTIME: 711 case RTP_PRIO_NORMAL: 712 case RTP_PRIO_IDLE: 713 if (rtp.prio > RTP_PRIO_MAX) { 714 error = EINVAL; 715 break; 716 } 717 lp->lwp_rtprio = rtp; 718 error = 0; 719 break; 720 default: 721 error = EINVAL; 722 break; 723 } 724 break; 725 default: 726 error = EINVAL; 727 break; 728 } 729 done: 730 if (p) 731 PRELE(p); 732 lwkt_reltoken(&proc_token); 733 734 return (error); 735 } 736 737 /* 738 * MPSAFE 739 */ 740 int 741 sys_setrlimit(struct __setrlimit_args *uap) 742 { 743 struct rlimit alim; 744 int error; 745 746 error = copyin(uap->rlp, &alim, sizeof(alim)); 747 if (error) 748 return (error); 749 750 error = kern_setrlimit(uap->which, &alim); 751 752 return (error); 753 } 754 755 /* 756 * MPSAFE 757 */ 758 int 759 sys_getrlimit(struct __getrlimit_args *uap) 760 { 761 struct rlimit lim; 762 int error; 763 764 error = kern_getrlimit(uap->which, &lim); 765 766 if (error == 0) 767 error = copyout(&lim, uap->rlp, sizeof(*uap->rlp)); 768 return error; 769 } 770 771 /* 772 * Transform the running time and tick information in lwp lp's thread into user, 773 * system, and interrupt time usage. 774 * 775 * Since we are limited to statclock tick granularity this is a statisical 776 * calculation which will be correct over the long haul, but should not be 777 * expected to measure fine grained deltas. 778 * 779 * It is possible to catch a lwp in the midst of being created, so 780 * check whether lwp_thread is NULL or not. 781 */ 782 void 783 calcru(struct lwp *lp, struct timeval *up, struct timeval *sp) 784 { 785 struct thread *td; 786 787 /* 788 * Calculate at the statclock level. YYY if the thread is owned by 789 * another cpu we need to forward the request to the other cpu, or 790 * have a token to interlock the information in order to avoid racing 791 * thread destruction. 792 */ 793 if ((td = lp->lwp_thread) != NULL) { 794 crit_enter(); 795 up->tv_sec = td->td_uticks / 1000000; 796 up->tv_usec = td->td_uticks % 1000000; 797 sp->tv_sec = td->td_sticks / 1000000; 798 sp->tv_usec = td->td_sticks % 1000000; 799 crit_exit(); 800 } 801 } 802 803 /* 804 * Aggregate resource statistics of all lwps of a process. 805 * 806 * proc.p_ru keeps track of all statistics directly related to a proc. This 807 * consists of RSS usage and nswap information and aggregate numbers for all 808 * former lwps of this proc. 809 * 810 * proc.p_cru is the sum of all stats of reaped children. 811 * 812 * lwp.lwp_ru contains the stats directly related to one specific lwp, meaning 813 * packet, scheduler switch or page fault counts, etc. This information gets 814 * added to lwp.lwp_proc.p_ru when the lwp exits. 815 */ 816 void 817 calcru_proc(struct proc *p, struct rusage *ru) 818 { 819 struct timeval upt, spt; 820 long *rip1, *rip2; 821 struct lwp *lp; 822 823 *ru = p->p_ru; 824 825 FOREACH_LWP_IN_PROC(lp, p) { 826 calcru(lp, &upt, &spt); 827 timevaladd(&ru->ru_utime, &upt); 828 timevaladd(&ru->ru_stime, &spt); 829 for (rip1 = &ru->ru_first, rip2 = &lp->lwp_ru.ru_first; 830 rip1 <= &ru->ru_last; 831 rip1++, rip2++) 832 *rip1 += *rip2; 833 } 834 } 835 836 837 /* 838 * MPALMOSTSAFE 839 */ 840 int 841 sys_getrusage(struct getrusage_args *uap) 842 { 843 struct rusage ru; 844 struct rusage *rup; 845 int error; 846 847 lwkt_gettoken(&proc_token); 848 849 switch (uap->who) { 850 case RUSAGE_SELF: 851 rup = &ru; 852 calcru_proc(curproc, rup); 853 error = 0; 854 break; 855 case RUSAGE_CHILDREN: 856 rup = &curproc->p_cru; 857 error = 0; 858 break; 859 default: 860 error = EINVAL; 861 break; 862 } 863 if (error == 0) 864 error = copyout(rup, uap->rusage, sizeof(struct rusage)); 865 lwkt_reltoken(&proc_token); 866 return (error); 867 } 868 869 void 870 ruadd(struct rusage *ru, struct rusage *ru2) 871 { 872 long *ip, *ip2; 873 int i; 874 875 timevaladd(&ru->ru_utime, &ru2->ru_utime); 876 timevaladd(&ru->ru_stime, &ru2->ru_stime); 877 if (ru->ru_maxrss < ru2->ru_maxrss) 878 ru->ru_maxrss = ru2->ru_maxrss; 879 ip = &ru->ru_first; ip2 = &ru2->ru_first; 880 for (i = &ru->ru_last - &ru->ru_first; i >= 0; i--) 881 *ip++ += *ip2++; 882 } 883 884 /* 885 * Find the uidinfo structure for a uid. This structure is used to 886 * track the total resource consumption (process count, socket buffer 887 * size, etc.) for the uid and impose limits. 888 */ 889 void 890 uihashinit(void) 891 { 892 spin_init(&uihash_lock); 893 uihashtbl = hashinit(maxproc / 16, M_UIDINFO, &uihash); 894 } 895 896 /* 897 * NOTE: Must be called with uihash_lock held 898 * 899 * MPSAFE 900 */ 901 static struct uidinfo * 902 uilookup(uid_t uid) 903 { 904 struct uihashhead *uipp; 905 struct uidinfo *uip; 906 907 uipp = UIHASH(uid); 908 LIST_FOREACH(uip, uipp, ui_hash) { 909 if (uip->ui_uid == uid) 910 break; 911 } 912 return (uip); 913 } 914 915 /* 916 * Helper function to creat ea uid that could not be found. 917 * This function will properly deal with races. 918 * 919 * MPSAFE 920 */ 921 static struct uidinfo * 922 uicreate(uid_t uid) 923 { 924 struct uidinfo *uip, *tmp; 925 926 /* 927 * Allocate space and check for a race 928 */ 929 uip = kmalloc(sizeof(*uip), M_UIDINFO, M_WAITOK|M_ZERO); 930 931 /* 932 * Initialize structure and enter it into the hash table 933 */ 934 spin_init(&uip->ui_lock); 935 uip->ui_uid = uid; 936 uip->ui_ref = 1; /* we're returning a ref */ 937 varsymset_init(&uip->ui_varsymset, NULL); 938 939 /* 940 * Somebody may have already created the uidinfo for this 941 * uid. If so, return that instead. 942 */ 943 spin_lock(&uihash_lock); 944 tmp = uilookup(uid); 945 if (tmp != NULL) { 946 uihold(tmp); 947 spin_unlock(&uihash_lock); 948 949 spin_uninit(&uip->ui_lock); 950 varsymset_clean(&uip->ui_varsymset); 951 FREE(uip, M_UIDINFO); 952 uip = tmp; 953 } else { 954 LIST_INSERT_HEAD(UIHASH(uid), uip, ui_hash); 955 spin_unlock(&uihash_lock); 956 } 957 return (uip); 958 } 959 960 /* 961 * 962 * 963 * MPSAFE 964 */ 965 struct uidinfo * 966 uifind(uid_t uid) 967 { 968 struct uidinfo *uip; 969 970 spin_lock(&uihash_lock); 971 uip = uilookup(uid); 972 if (uip == NULL) { 973 spin_unlock(&uihash_lock); 974 uip = uicreate(uid); 975 } else { 976 uihold(uip); 977 spin_unlock(&uihash_lock); 978 } 979 return (uip); 980 } 981 982 /* 983 * Helper funtion to remove a uidinfo whos reference count is 984 * transitioning from 1->0. The reference count is 1 on call. 985 * 986 * Zero is returned on success, otherwise non-zero and the 987 * uiphas not been removed. 988 * 989 * MPSAFE 990 */ 991 static __inline int 992 uifree(struct uidinfo *uip) 993 { 994 /* 995 * If we are still the only holder after acquiring the uihash_lock 996 * we can safely unlink the uip and destroy it. Otherwise we lost 997 * a race and must fail. 998 */ 999 spin_lock(&uihash_lock); 1000 if (uip->ui_ref != 1) { 1001 spin_unlock(&uihash_lock); 1002 return(-1); 1003 } 1004 LIST_REMOVE(uip, ui_hash); 1005 spin_unlock(&uihash_lock); 1006 1007 /* 1008 * The uip is now orphaned and we can destroy it at our 1009 * leisure. 1010 */ 1011 if (uip->ui_sbsize != 0) 1012 kprintf("freeing uidinfo: uid = %d, sbsize = %jd\n", 1013 uip->ui_uid, (intmax_t)uip->ui_sbsize); 1014 if (uip->ui_proccnt != 0) 1015 kprintf("freeing uidinfo: uid = %d, proccnt = %ld\n", 1016 uip->ui_uid, uip->ui_proccnt); 1017 1018 varsymset_clean(&uip->ui_varsymset); 1019 lockuninit(&uip->ui_varsymset.vx_lock); 1020 spin_uninit(&uip->ui_lock); 1021 FREE(uip, M_UIDINFO); 1022 return(0); 1023 } 1024 1025 /* 1026 * MPSAFE 1027 */ 1028 void 1029 uihold(struct uidinfo *uip) 1030 { 1031 atomic_add_int(&uip->ui_ref, 1); 1032 KKASSERT(uip->ui_ref >= 0); 1033 } 1034 1035 /* 1036 * NOTE: It is important for us to not drop the ref count to 0 1037 * because this can cause a 2->0/2->0 race with another 1038 * concurrent dropper. Losing the race in that situation 1039 * can cause uip to become stale for one of the other 1040 * threads. 1041 * 1042 * MPSAFE 1043 */ 1044 void 1045 uidrop(struct uidinfo *uip) 1046 { 1047 int ref; 1048 1049 KKASSERT(uip->ui_ref > 0); 1050 1051 for (;;) { 1052 ref = uip->ui_ref; 1053 cpu_ccfence(); 1054 if (ref == 1) { 1055 if (uifree(uip) == 0) 1056 break; 1057 } else if (atomic_cmpset_int(&uip->ui_ref, ref, ref - 1)) { 1058 break; 1059 } 1060 /* else retry */ 1061 } 1062 } 1063 1064 void 1065 uireplace(struct uidinfo **puip, struct uidinfo *nuip) 1066 { 1067 uidrop(*puip); 1068 *puip = nuip; 1069 } 1070 1071 /* 1072 * Change the count associated with number of processes 1073 * a given user is using. When 'max' is 0, don't enforce a limit 1074 */ 1075 int 1076 chgproccnt(struct uidinfo *uip, int diff, int max) 1077 { 1078 int ret; 1079 spin_lock(&uip->ui_lock); 1080 /* don't allow them to exceed max, but allow subtraction */ 1081 if (diff > 0 && uip->ui_proccnt + diff > max && max != 0) { 1082 ret = 0; 1083 } else { 1084 uip->ui_proccnt += diff; 1085 if (uip->ui_proccnt < 0) 1086 kprintf("negative proccnt for uid = %d\n", uip->ui_uid); 1087 ret = 1; 1088 } 1089 spin_unlock(&uip->ui_lock); 1090 return ret; 1091 } 1092 1093 /* 1094 * Change the total socket buffer size a user has used. 1095 */ 1096 int 1097 chgsbsize(struct uidinfo *uip, u_long *hiwat, u_long to, rlim_t max) 1098 { 1099 rlim_t new; 1100 1101 spin_lock(&uip->ui_lock); 1102 new = uip->ui_sbsize + to - *hiwat; 1103 KKASSERT(new >= 0); 1104 1105 /* 1106 * If we are trying to increase the socket buffer size 1107 * Scale down the hi water mark when we exceed the user's 1108 * allowed socket buffer space. 1109 * 1110 * We can't scale down too much or we will blow up atomic packet 1111 * operations. 1112 */ 1113 if (to > *hiwat && to > MCLBYTES && new > max) { 1114 to = to * max / new; 1115 if (to < MCLBYTES) 1116 to = MCLBYTES; 1117 } 1118 uip->ui_sbsize = new; 1119 *hiwat = to; 1120 spin_unlock(&uip->ui_lock); 1121 return (1); 1122 } 1123 1124