xref: /freebsd/sys/kern/kern_resource.c (revision 3157ba21)
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  * 4. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  *	@(#)kern_resource.c	8.5 (Berkeley) 1/21/94
35  */
36 
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
39 
40 #include "opt_compat.h"
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/resourcevar.h>
54 #include <sys/rwlock.h>
55 #include <sys/sched.h>
56 #include <sys/sx.h>
57 #include <sys/syscallsubr.h>
58 #include <sys/sysent.h>
59 #include <sys/time.h>
60 #include <sys/umtx.h>
61 
62 #include <vm/vm.h>
63 #include <vm/vm_param.h>
64 #include <vm/pmap.h>
65 #include <vm/vm_map.h>
66 
67 
68 static MALLOC_DEFINE(M_PLIMIT, "plimit", "plimit structures");
69 static MALLOC_DEFINE(M_UIDINFO, "uidinfo", "uidinfo structures");
70 #define	UIHASH(uid)	(&uihashtbl[(uid) & uihash])
71 static struct rwlock uihashtbl_lock;
72 static LIST_HEAD(uihashhead, uidinfo) *uihashtbl;
73 static u_long uihash;		/* size of hash table - 1 */
74 
75 static void	calcru1(struct proc *p, struct rusage_ext *ruxp,
76 		    struct timeval *up, struct timeval *sp);
77 static int	donice(struct thread *td, struct proc *chgp, int n);
78 static struct uidinfo *uilookup(uid_t uid);
79 static void	ruxagg_locked(struct rusage_ext *rux, struct thread *td);
80 
81 /*
82  * Resource controls and accounting.
83  */
84 #ifndef _SYS_SYSPROTO_H_
85 struct getpriority_args {
86 	int	which;
87 	int	who;
88 };
89 #endif
90 int
91 getpriority(td, uap)
92 	struct thread *td;
93 	register struct getpriority_args *uap;
94 {
95 	struct proc *p;
96 	struct pgrp *pg;
97 	int error, low;
98 
99 	error = 0;
100 	low = PRIO_MAX + 1;
101 	switch (uap->which) {
102 
103 	case PRIO_PROCESS:
104 		if (uap->who == 0)
105 			low = td->td_proc->p_nice;
106 		else {
107 			p = pfind(uap->who);
108 			if (p == NULL)
109 				break;
110 			if (p_cansee(td, p) == 0)
111 				low = p->p_nice;
112 			PROC_UNLOCK(p);
113 		}
114 		break;
115 
116 	case PRIO_PGRP:
117 		sx_slock(&proctree_lock);
118 		if (uap->who == 0) {
119 			pg = td->td_proc->p_pgrp;
120 			PGRP_LOCK(pg);
121 		} else {
122 			pg = pgfind(uap->who);
123 			if (pg == NULL) {
124 				sx_sunlock(&proctree_lock);
125 				break;
126 			}
127 		}
128 		sx_sunlock(&proctree_lock);
129 		LIST_FOREACH(p, &pg->pg_members, p_pglist) {
130 			PROC_LOCK(p);
131 			if (p_cansee(td, p) == 0) {
132 				if (p->p_nice < low)
133 					low = p->p_nice;
134 			}
135 			PROC_UNLOCK(p);
136 		}
137 		PGRP_UNLOCK(pg);
138 		break;
139 
140 	case PRIO_USER:
141 		if (uap->who == 0)
142 			uap->who = td->td_ucred->cr_uid;
143 		sx_slock(&allproc_lock);
144 		FOREACH_PROC_IN_SYSTEM(p) {
145 			/* Do not bother to check PRS_NEW processes */
146 			if (p->p_state == PRS_NEW)
147 				continue;
148 			PROC_LOCK(p);
149 			if (p_cansee(td, p) == 0 &&
150 			    p->p_ucred->cr_uid == uap->who) {
151 				if (p->p_nice < low)
152 					low = p->p_nice;
153 			}
154 			PROC_UNLOCK(p);
155 		}
156 		sx_sunlock(&allproc_lock);
157 		break;
158 
159 	default:
160 		error = EINVAL;
161 		break;
162 	}
163 	if (low == PRIO_MAX + 1 && error == 0)
164 		error = ESRCH;
165 	td->td_retval[0] = low;
166 	return (error);
167 }
168 
169 #ifndef _SYS_SYSPROTO_H_
170 struct setpriority_args {
171 	int	which;
172 	int	who;
173 	int	prio;
174 };
175 #endif
176 int
177 setpriority(td, uap)
178 	struct thread *td;
179 	struct setpriority_args *uap;
180 {
181 	struct proc *curp, *p;
182 	struct pgrp *pg;
183 	int found = 0, error = 0;
184 
185 	curp = td->td_proc;
186 	switch (uap->which) {
187 	case PRIO_PROCESS:
188 		if (uap->who == 0) {
189 			PROC_LOCK(curp);
190 			error = donice(td, curp, uap->prio);
191 			PROC_UNLOCK(curp);
192 		} else {
193 			p = pfind(uap->who);
194 			if (p == NULL)
195 				break;
196 			error = p_cansee(td, p);
197 			if (error == 0)
198 				error = donice(td, p, uap->prio);
199 			PROC_UNLOCK(p);
200 		}
201 		found++;
202 		break;
203 
204 	case PRIO_PGRP:
205 		sx_slock(&proctree_lock);
206 		if (uap->who == 0) {
207 			pg = curp->p_pgrp;
208 			PGRP_LOCK(pg);
209 		} else {
210 			pg = pgfind(uap->who);
211 			if (pg == NULL) {
212 				sx_sunlock(&proctree_lock);
213 				break;
214 			}
215 		}
216 		sx_sunlock(&proctree_lock);
217 		LIST_FOREACH(p, &pg->pg_members, p_pglist) {
218 			PROC_LOCK(p);
219 			if (p_cansee(td, p) == 0) {
220 				error = donice(td, p, uap->prio);
221 				found++;
222 			}
223 			PROC_UNLOCK(p);
224 		}
225 		PGRP_UNLOCK(pg);
226 		break;
227 
228 	case PRIO_USER:
229 		if (uap->who == 0)
230 			uap->who = td->td_ucred->cr_uid;
231 		sx_slock(&allproc_lock);
232 		FOREACH_PROC_IN_SYSTEM(p) {
233 			PROC_LOCK(p);
234 			if (p->p_ucred->cr_uid == uap->who &&
235 			    p_cansee(td, p) == 0) {
236 				error = donice(td, p, uap->prio);
237 				found++;
238 			}
239 			PROC_UNLOCK(p);
240 		}
241 		sx_sunlock(&allproc_lock);
242 		break;
243 
244 	default:
245 		error = EINVAL;
246 		break;
247 	}
248 	if (found == 0 && error == 0)
249 		error = ESRCH;
250 	return (error);
251 }
252 
253 /*
254  * Set "nice" for a (whole) process.
255  */
256 static int
257 donice(struct thread *td, struct proc *p, int n)
258 {
259 	int error;
260 
261 	PROC_LOCK_ASSERT(p, MA_OWNED);
262 	if ((error = p_cansched(td, p)))
263 		return (error);
264 	if (n > PRIO_MAX)
265 		n = PRIO_MAX;
266 	if (n < PRIO_MIN)
267 		n = PRIO_MIN;
268 	if (n < p->p_nice && priv_check(td, PRIV_SCHED_SETPRIORITY) != 0)
269 		return (EACCES);
270 	sched_nice(p, n);
271 	return (0);
272 }
273 
274 /*
275  * Set realtime priority for LWP.
276  */
277 #ifndef _SYS_SYSPROTO_H_
278 struct rtprio_thread_args {
279 	int		function;
280 	lwpid_t		lwpid;
281 	struct rtprio	*rtp;
282 };
283 #endif
284 int
285 rtprio_thread(struct thread *td, struct rtprio_thread_args *uap)
286 {
287 	struct proc *p;
288 	struct rtprio rtp;
289 	struct thread *td1;
290 	int cierror, error;
291 
292 	/* Perform copyin before acquiring locks if needed. */
293 	if (uap->function == RTP_SET)
294 		cierror = copyin(uap->rtp, &rtp, sizeof(struct rtprio));
295 	else
296 		cierror = 0;
297 
298 	/*
299 	 * Though lwpid is unique, only current process is supported
300 	 * since there is no efficient way to look up a LWP yet.
301 	 */
302 	p = td->td_proc;
303 	PROC_LOCK(p);
304 
305 	switch (uap->function) {
306 	case RTP_LOOKUP:
307 		if ((error = p_cansee(td, p)))
308 			break;
309 		if (uap->lwpid == 0 || uap->lwpid == td->td_tid)
310 			td1 = td;
311 		else
312 			td1 = thread_find(p, uap->lwpid);
313 		if (td1 != NULL)
314 			pri_to_rtp(td1, &rtp);
315 		else
316 			error = ESRCH;
317 		PROC_UNLOCK(p);
318 		return (copyout(&rtp, uap->rtp, sizeof(struct rtprio)));
319 	case RTP_SET:
320 		if ((error = p_cansched(td, p)) || (error = cierror))
321 			break;
322 
323 		/* Disallow setting rtprio in most cases if not superuser. */
324 /*
325  * Realtime priority has to be restricted for reasons which should be
326  * obvious.  However, for idle priority, there is a potential for
327  * system deadlock if an idleprio process gains a lock on a resource
328  * that other processes need (and the idleprio process can't run
329  * due to a CPU-bound normal process).  Fix me!  XXX
330  */
331 #if 0
332 		if (RTP_PRIO_IS_REALTIME(rtp.type)) {
333 #else
334 		if (rtp.type != RTP_PRIO_NORMAL) {
335 #endif
336 			error = priv_check(td, PRIV_SCHED_RTPRIO);
337 			if (error)
338 				break;
339 		}
340 
341 		if (uap->lwpid == 0 || uap->lwpid == td->td_tid)
342 			td1 = td;
343 		else
344 			td1 = thread_find(p, uap->lwpid);
345 		if (td1 != NULL)
346 			error = rtp_to_pri(&rtp, td1);
347 		else
348 			error = ESRCH;
349 		break;
350 	default:
351 		error = EINVAL;
352 		break;
353 	}
354 	PROC_UNLOCK(p);
355 	return (error);
356 }
357 
358 /*
359  * Set realtime priority.
360  */
361 #ifndef _SYS_SYSPROTO_H_
362 struct rtprio_args {
363 	int		function;
364 	pid_t		pid;
365 	struct rtprio	*rtp;
366 };
367 #endif
368 int
369 rtprio(td, uap)
370 	struct thread *td;		/* curthread */
371 	register struct rtprio_args *uap;
372 {
373 	struct proc *p;
374 	struct thread *tdp;
375 	struct rtprio rtp;
376 	int cierror, error;
377 
378 	/* Perform copyin before acquiring locks if needed. */
379 	if (uap->function == RTP_SET)
380 		cierror = copyin(uap->rtp, &rtp, sizeof(struct rtprio));
381 	else
382 		cierror = 0;
383 
384 	if (uap->pid == 0) {
385 		p = td->td_proc;
386 		PROC_LOCK(p);
387 	} else {
388 		p = pfind(uap->pid);
389 		if (p == NULL)
390 			return (ESRCH);
391 	}
392 
393 	switch (uap->function) {
394 	case RTP_LOOKUP:
395 		if ((error = p_cansee(td, p)))
396 			break;
397 		/*
398 		 * Return OUR priority if no pid specified,
399 		 * or if one is, report the highest priority
400 		 * in the process.  There isn't much more you can do as
401 		 * there is only room to return a single priority.
402 		 * Note: specifying our own pid is not the same
403 		 * as leaving it zero.
404 		 */
405 		if (uap->pid == 0) {
406 			pri_to_rtp(td, &rtp);
407 		} else {
408 			struct rtprio rtp2;
409 
410 			rtp.type = RTP_PRIO_IDLE;
411 			rtp.prio = RTP_PRIO_MAX;
412 			FOREACH_THREAD_IN_PROC(p, tdp) {
413 				pri_to_rtp(tdp, &rtp2);
414 				if (rtp2.type <  rtp.type ||
415 				    (rtp2.type == rtp.type &&
416 				    rtp2.prio < rtp.prio)) {
417 					rtp.type = rtp2.type;
418 					rtp.prio = rtp2.prio;
419 				}
420 			}
421 		}
422 		PROC_UNLOCK(p);
423 		return (copyout(&rtp, uap->rtp, sizeof(struct rtprio)));
424 	case RTP_SET:
425 		if ((error = p_cansched(td, p)) || (error = cierror))
426 			break;
427 
428 		/* Disallow setting rtprio in most cases if not superuser. */
429 /*
430  * Realtime priority has to be restricted for reasons which should be
431  * obvious.  However, for idle priority, there is a potential for
432  * system deadlock if an idleprio process gains a lock on a resource
433  * that other processes need (and the idleprio process can't run
434  * due to a CPU-bound normal process).  Fix me!  XXX
435  */
436 #if 0
437 		if (RTP_PRIO_IS_REALTIME(rtp.type)) {
438 #else
439 		if (rtp.type != RTP_PRIO_NORMAL) {
440 #endif
441 			error = priv_check(td, PRIV_SCHED_RTPRIO);
442 			if (error)
443 				break;
444 		}
445 
446 		/*
447 		 * If we are setting our own priority, set just our
448 		 * thread but if we are doing another process,
449 		 * do all the threads on that process. If we
450 		 * specify our own pid we do the latter.
451 		 */
452 		if (uap->pid == 0) {
453 			error = rtp_to_pri(&rtp, td);
454 		} else {
455 			FOREACH_THREAD_IN_PROC(p, td) {
456 				if ((error = rtp_to_pri(&rtp, td)) != 0)
457 					break;
458 			}
459 		}
460 		break;
461 	default:
462 		error = EINVAL;
463 		break;
464 	}
465 	PROC_UNLOCK(p);
466 	return (error);
467 }
468 
469 int
470 rtp_to_pri(struct rtprio *rtp, struct thread *td)
471 {
472 	u_char	newpri;
473 	u_char	oldpri;
474 
475 	thread_lock(td);
476 	switch (RTP_PRIO_BASE(rtp->type)) {
477 	case RTP_PRIO_REALTIME:
478 		if (rtp->prio > RTP_PRIO_MAX) {
479 			thread_unlock(td);
480 			return (EINVAL);
481 		}
482 		newpri = PRI_MIN_REALTIME + rtp->prio;
483 		break;
484 	case RTP_PRIO_NORMAL:
485 		if (rtp->prio >  (PRI_MAX_TIMESHARE - PRI_MIN_TIMESHARE)) {
486 			thread_unlock(td);
487 			return (EINVAL);
488 		}
489 		newpri = PRI_MIN_TIMESHARE + rtp->prio;
490 		break;
491 	case RTP_PRIO_IDLE:
492 		newpri = PRI_MIN_IDLE + rtp->prio;
493 		break;
494 	default:
495 		thread_unlock(td);
496 		return (EINVAL);
497 	}
498 	sched_class(td, rtp->type);	/* XXX fix */
499 	oldpri = td->td_user_pri;
500 	sched_user_prio(td, newpri);
501 	if (curthread == td)
502 		sched_prio(curthread, td->td_user_pri); /* XXX dubious */
503 	if (TD_ON_UPILOCK(td) && oldpri != newpri) {
504 		thread_unlock(td);
505 		umtx_pi_adjust(td, oldpri);
506 	} else
507 		thread_unlock(td);
508 	return (0);
509 }
510 
511 void
512 pri_to_rtp(struct thread *td, struct rtprio *rtp)
513 {
514 
515 	thread_lock(td);
516 	switch (PRI_BASE(td->td_pri_class)) {
517 	case PRI_REALTIME:
518 		rtp->prio = td->td_base_user_pri - PRI_MIN_REALTIME;
519 		break;
520 	case PRI_TIMESHARE:
521 		rtp->prio = td->td_base_user_pri - PRI_MIN_TIMESHARE;
522 		break;
523 	case PRI_IDLE:
524 		rtp->prio = td->td_base_user_pri - PRI_MIN_IDLE;
525 		break;
526 	default:
527 		break;
528 	}
529 	rtp->type = td->td_pri_class;
530 	thread_unlock(td);
531 }
532 
533 #if defined(COMPAT_43)
534 #ifndef _SYS_SYSPROTO_H_
535 struct osetrlimit_args {
536 	u_int	which;
537 	struct	orlimit *rlp;
538 };
539 #endif
540 int
541 osetrlimit(td, uap)
542 	struct thread *td;
543 	register struct osetrlimit_args *uap;
544 {
545 	struct orlimit olim;
546 	struct rlimit lim;
547 	int error;
548 
549 	if ((error = copyin(uap->rlp, &olim, sizeof(struct orlimit))))
550 		return (error);
551 	lim.rlim_cur = olim.rlim_cur;
552 	lim.rlim_max = olim.rlim_max;
553 	error = kern_setrlimit(td, uap->which, &lim);
554 	return (error);
555 }
556 
557 #ifndef _SYS_SYSPROTO_H_
558 struct ogetrlimit_args {
559 	u_int	which;
560 	struct	orlimit *rlp;
561 };
562 #endif
563 int
564 ogetrlimit(td, uap)
565 	struct thread *td;
566 	register struct ogetrlimit_args *uap;
567 {
568 	struct orlimit olim;
569 	struct rlimit rl;
570 	struct proc *p;
571 	int error;
572 
573 	if (uap->which >= RLIM_NLIMITS)
574 		return (EINVAL);
575 	p = td->td_proc;
576 	PROC_LOCK(p);
577 	lim_rlimit(p, uap->which, &rl);
578 	PROC_UNLOCK(p);
579 
580 	/*
581 	 * XXX would be more correct to convert only RLIM_INFINITY to the
582 	 * old RLIM_INFINITY and fail with EOVERFLOW for other larger
583 	 * values.  Most 64->32 and 32->16 conversions, including not
584 	 * unimportant ones of uids are even more broken than what we
585 	 * do here (they blindly truncate).  We don't do this correctly
586 	 * here since we have little experience with EOVERFLOW yet.
587 	 * Elsewhere, getuid() can't fail...
588 	 */
589 	olim.rlim_cur = rl.rlim_cur > 0x7fffffff ? 0x7fffffff : rl.rlim_cur;
590 	olim.rlim_max = rl.rlim_max > 0x7fffffff ? 0x7fffffff : rl.rlim_max;
591 	error = copyout(&olim, uap->rlp, sizeof(olim));
592 	return (error);
593 }
594 #endif /* COMPAT_43 */
595 
596 #ifndef _SYS_SYSPROTO_H_
597 struct __setrlimit_args {
598 	u_int	which;
599 	struct	rlimit *rlp;
600 };
601 #endif
602 int
603 setrlimit(td, uap)
604 	struct thread *td;
605 	register struct __setrlimit_args *uap;
606 {
607 	struct rlimit alim;
608 	int error;
609 
610 	if ((error = copyin(uap->rlp, &alim, sizeof(struct rlimit))))
611 		return (error);
612 	error = kern_setrlimit(td, uap->which, &alim);
613 	return (error);
614 }
615 
616 static void
617 lim_cb(void *arg)
618 {
619 	struct rlimit rlim;
620 	struct thread *td;
621 	struct proc *p;
622 
623 	p = arg;
624 	PROC_LOCK_ASSERT(p, MA_OWNED);
625 	/*
626 	 * Check if the process exceeds its cpu resource allocation.  If
627 	 * it reaches the max, arrange to kill the process in ast().
628 	 */
629 	if (p->p_cpulimit == RLIM_INFINITY)
630 		return;
631 	PROC_SLOCK(p);
632 	FOREACH_THREAD_IN_PROC(p, td) {
633 		ruxagg(p, td);
634 	}
635 	PROC_SUNLOCK(p);
636 	if (p->p_rux.rux_runtime > p->p_cpulimit * cpu_tickrate()) {
637 		lim_rlimit(p, RLIMIT_CPU, &rlim);
638 		if (p->p_rux.rux_runtime >= rlim.rlim_max * cpu_tickrate()) {
639 			killproc(p, "exceeded maximum CPU limit");
640 		} else {
641 			if (p->p_cpulimit < rlim.rlim_max)
642 				p->p_cpulimit += 5;
643 			psignal(p, SIGXCPU);
644 		}
645 	}
646 	if ((p->p_flag & P_WEXIT) == 0)
647 		callout_reset(&p->p_limco, hz, lim_cb, p);
648 }
649 
650 int
651 kern_setrlimit(td, which, limp)
652 	struct thread *td;
653 	u_int which;
654 	struct rlimit *limp;
655 {
656 	struct plimit *newlim, *oldlim;
657 	struct proc *p;
658 	register struct rlimit *alimp;
659 	struct rlimit oldssiz;
660 	int error;
661 
662 	if (which >= RLIM_NLIMITS)
663 		return (EINVAL);
664 
665 	/*
666 	 * Preserve historical bugs by treating negative limits as unsigned.
667 	 */
668 	if (limp->rlim_cur < 0)
669 		limp->rlim_cur = RLIM_INFINITY;
670 	if (limp->rlim_max < 0)
671 		limp->rlim_max = RLIM_INFINITY;
672 
673 	oldssiz.rlim_cur = 0;
674 	p = td->td_proc;
675 	newlim = lim_alloc();
676 	PROC_LOCK(p);
677 	oldlim = p->p_limit;
678 	alimp = &oldlim->pl_rlimit[which];
679 	if (limp->rlim_cur > alimp->rlim_max ||
680 	    limp->rlim_max > alimp->rlim_max)
681 		if ((error = priv_check(td, PRIV_PROC_SETRLIMIT))) {
682 			PROC_UNLOCK(p);
683 			lim_free(newlim);
684 			return (error);
685 		}
686 	if (limp->rlim_cur > limp->rlim_max)
687 		limp->rlim_cur = limp->rlim_max;
688 	lim_copy(newlim, oldlim);
689 	alimp = &newlim->pl_rlimit[which];
690 
691 	switch (which) {
692 
693 	case RLIMIT_CPU:
694 		if (limp->rlim_cur != RLIM_INFINITY &&
695 		    p->p_cpulimit == RLIM_INFINITY)
696 			callout_reset(&p->p_limco, hz, lim_cb, p);
697 		p->p_cpulimit = limp->rlim_cur;
698 		break;
699 	case RLIMIT_DATA:
700 		if (limp->rlim_cur > maxdsiz)
701 			limp->rlim_cur = maxdsiz;
702 		if (limp->rlim_max > maxdsiz)
703 			limp->rlim_max = maxdsiz;
704 		break;
705 
706 	case RLIMIT_STACK:
707 		if (limp->rlim_cur > maxssiz)
708 			limp->rlim_cur = maxssiz;
709 		if (limp->rlim_max > maxssiz)
710 			limp->rlim_max = maxssiz;
711 		oldssiz = *alimp;
712 		if (td->td_proc->p_sysent->sv_fixlimit != NULL)
713 			td->td_proc->p_sysent->sv_fixlimit(&oldssiz,
714 			    RLIMIT_STACK);
715 		break;
716 
717 	case RLIMIT_NOFILE:
718 		if (limp->rlim_cur > maxfilesperproc)
719 			limp->rlim_cur = maxfilesperproc;
720 		if (limp->rlim_max > maxfilesperproc)
721 			limp->rlim_max = maxfilesperproc;
722 		break;
723 
724 	case RLIMIT_NPROC:
725 		if (limp->rlim_cur > maxprocperuid)
726 			limp->rlim_cur = maxprocperuid;
727 		if (limp->rlim_max > maxprocperuid)
728 			limp->rlim_max = maxprocperuid;
729 		if (limp->rlim_cur < 1)
730 			limp->rlim_cur = 1;
731 		if (limp->rlim_max < 1)
732 			limp->rlim_max = 1;
733 		break;
734 	}
735 	if (td->td_proc->p_sysent->sv_fixlimit != NULL)
736 		td->td_proc->p_sysent->sv_fixlimit(limp, which);
737 	*alimp = *limp;
738 	p->p_limit = newlim;
739 	PROC_UNLOCK(p);
740 	lim_free(oldlim);
741 
742 	if (which == RLIMIT_STACK) {
743 		/*
744 		 * Stack is allocated to the max at exec time with only
745 		 * "rlim_cur" bytes accessible.  If stack limit is going
746 		 * up make more accessible, if going down make inaccessible.
747 		 */
748 		if (limp->rlim_cur != oldssiz.rlim_cur) {
749 			vm_offset_t addr;
750 			vm_size_t size;
751 			vm_prot_t prot;
752 
753 			if (limp->rlim_cur > oldssiz.rlim_cur) {
754 				prot = p->p_sysent->sv_stackprot;
755 				size = limp->rlim_cur - oldssiz.rlim_cur;
756 				addr = p->p_sysent->sv_usrstack -
757 				    limp->rlim_cur;
758 			} else {
759 				prot = VM_PROT_NONE;
760 				size = oldssiz.rlim_cur - limp->rlim_cur;
761 				addr = p->p_sysent->sv_usrstack -
762 				    oldssiz.rlim_cur;
763 			}
764 			addr = trunc_page(addr);
765 			size = round_page(size);
766 			(void)vm_map_protect(&p->p_vmspace->vm_map,
767 			    addr, addr + size, prot, FALSE);
768 		}
769 	}
770 
771 	return (0);
772 }
773 
774 #ifndef _SYS_SYSPROTO_H_
775 struct __getrlimit_args {
776 	u_int	which;
777 	struct	rlimit *rlp;
778 };
779 #endif
780 /* ARGSUSED */
781 int
782 getrlimit(td, uap)
783 	struct thread *td;
784 	register struct __getrlimit_args *uap;
785 {
786 	struct rlimit rlim;
787 	struct proc *p;
788 	int error;
789 
790 	if (uap->which >= RLIM_NLIMITS)
791 		return (EINVAL);
792 	p = td->td_proc;
793 	PROC_LOCK(p);
794 	lim_rlimit(p, uap->which, &rlim);
795 	PROC_UNLOCK(p);
796 	error = copyout(&rlim, uap->rlp, sizeof(struct rlimit));
797 	return (error);
798 }
799 
800 /*
801  * Transform the running time and tick information for children of proc p
802  * into user and system time usage.
803  */
804 void
805 calccru(p, up, sp)
806 	struct proc *p;
807 	struct timeval *up;
808 	struct timeval *sp;
809 {
810 
811 	PROC_LOCK_ASSERT(p, MA_OWNED);
812 	calcru1(p, &p->p_crux, up, sp);
813 }
814 
815 /*
816  * Transform the running time and tick information in proc p into user
817  * and system time usage.  If appropriate, include the current time slice
818  * on this CPU.
819  */
820 void
821 calcru(struct proc *p, struct timeval *up, struct timeval *sp)
822 {
823 	struct thread *td;
824 	uint64_t u;
825 
826 	PROC_LOCK_ASSERT(p, MA_OWNED);
827 	PROC_SLOCK_ASSERT(p, MA_OWNED);
828 	/*
829 	 * If we are getting stats for the current process, then add in the
830 	 * stats that this thread has accumulated in its current time slice.
831 	 * We reset the thread and CPU state as if we had performed a context
832 	 * switch right here.
833 	 */
834 	td = curthread;
835 	if (td->td_proc == p) {
836 		u = cpu_ticks();
837 		p->p_rux.rux_runtime += u - PCPU_GET(switchtime);
838 		PCPU_SET(switchtime, u);
839 	}
840 	/* Make sure the per-thread stats are current. */
841 	FOREACH_THREAD_IN_PROC(p, td) {
842 		if (td->td_incruntime == 0)
843 			continue;
844 		ruxagg(p, td);
845 	}
846 	calcru1(p, &p->p_rux, up, sp);
847 }
848 
849 static void
850 calcru1(struct proc *p, struct rusage_ext *ruxp, struct timeval *up,
851     struct timeval *sp)
852 {
853 	/* {user, system, interrupt, total} {ticks, usec}: */
854 	u_int64_t ut, uu, st, su, it, tt, tu;
855 
856 	ut = ruxp->rux_uticks;
857 	st = ruxp->rux_sticks;
858 	it = ruxp->rux_iticks;
859 	tt = ut + st + it;
860 	if (tt == 0) {
861 		/* Avoid divide by zero */
862 		st = 1;
863 		tt = 1;
864 	}
865 	tu = cputick2usec(ruxp->rux_runtime);
866 	if ((int64_t)tu < 0) {
867 		/* XXX: this should be an assert /phk */
868 		printf("calcru: negative runtime of %jd usec for pid %d (%s)\n",
869 		    (intmax_t)tu, p->p_pid, p->p_comm);
870 		tu = ruxp->rux_tu;
871 	}
872 
873 	if (tu >= ruxp->rux_tu) {
874 		/*
875 		 * The normal case, time increased.
876 		 * Enforce monotonicity of bucketed numbers.
877 		 */
878 		uu = (tu * ut) / tt;
879 		if (uu < ruxp->rux_uu)
880 			uu = ruxp->rux_uu;
881 		su = (tu * st) / tt;
882 		if (su < ruxp->rux_su)
883 			su = ruxp->rux_su;
884 	} else if (tu + 3 > ruxp->rux_tu || 101 * tu > 100 * ruxp->rux_tu) {
885 		/*
886 		 * When we calibrate the cputicker, it is not uncommon to
887 		 * see the presumably fixed frequency increase slightly over
888 		 * time as a result of thermal stabilization and NTP
889 		 * discipline (of the reference clock).  We therefore ignore
890 		 * a bit of backwards slop because we  expect to catch up
891 		 * shortly.  We use a 3 microsecond limit to catch low
892 		 * counts and a 1% limit for high counts.
893 		 */
894 		uu = ruxp->rux_uu;
895 		su = ruxp->rux_su;
896 		tu = ruxp->rux_tu;
897 	} else { /* tu < ruxp->rux_tu */
898 		/*
899 		 * What happened here was likely that a laptop, which ran at
900 		 * a reduced clock frequency at boot, kicked into high gear.
901 		 * The wisdom of spamming this message in that case is
902 		 * dubious, but it might also be indicative of something
903 		 * serious, so lets keep it and hope laptops can be made
904 		 * more truthful about their CPU speed via ACPI.
905 		 */
906 		printf("calcru: runtime went backwards from %ju usec "
907 		    "to %ju usec for pid %d (%s)\n",
908 		    (uintmax_t)ruxp->rux_tu, (uintmax_t)tu,
909 		    p->p_pid, p->p_comm);
910 		uu = (tu * ut) / tt;
911 		su = (tu * st) / tt;
912 	}
913 
914 	ruxp->rux_uu = uu;
915 	ruxp->rux_su = su;
916 	ruxp->rux_tu = tu;
917 
918 	up->tv_sec = uu / 1000000;
919 	up->tv_usec = uu % 1000000;
920 	sp->tv_sec = su / 1000000;
921 	sp->tv_usec = su % 1000000;
922 }
923 
924 #ifndef _SYS_SYSPROTO_H_
925 struct getrusage_args {
926 	int	who;
927 	struct	rusage *rusage;
928 };
929 #endif
930 int
931 getrusage(td, uap)
932 	register struct thread *td;
933 	register struct getrusage_args *uap;
934 {
935 	struct rusage ru;
936 	int error;
937 
938 	error = kern_getrusage(td, uap->who, &ru);
939 	if (error == 0)
940 		error = copyout(&ru, uap->rusage, sizeof(struct rusage));
941 	return (error);
942 }
943 
944 int
945 kern_getrusage(struct thread *td, int who, struct rusage *rup)
946 {
947 	struct proc *p;
948 	int error;
949 
950 	error = 0;
951 	p = td->td_proc;
952 	PROC_LOCK(p);
953 	switch (who) {
954 	case RUSAGE_SELF:
955 		rufetchcalc(p, rup, &rup->ru_utime,
956 		    &rup->ru_stime);
957 		break;
958 
959 	case RUSAGE_CHILDREN:
960 		*rup = p->p_stats->p_cru;
961 		calccru(p, &rup->ru_utime, &rup->ru_stime);
962 		break;
963 
964 	case RUSAGE_THREAD:
965 		PROC_SLOCK(p);
966 		ruxagg(p, td);
967 		PROC_SUNLOCK(p);
968 		thread_lock(td);
969 		*rup = td->td_ru;
970 		calcru1(p, &td->td_rux, &rup->ru_utime, &rup->ru_stime);
971 		thread_unlock(td);
972 		break;
973 
974 	default:
975 		error = EINVAL;
976 	}
977 	PROC_UNLOCK(p);
978 	return (error);
979 }
980 
981 void
982 rucollect(struct rusage *ru, struct rusage *ru2)
983 {
984 	long *ip, *ip2;
985 	int i;
986 
987 	if (ru->ru_maxrss < ru2->ru_maxrss)
988 		ru->ru_maxrss = ru2->ru_maxrss;
989 	ip = &ru->ru_first;
990 	ip2 = &ru2->ru_first;
991 	for (i = &ru->ru_last - &ru->ru_first; i >= 0; i--)
992 		*ip++ += *ip2++;
993 }
994 
995 void
996 ruadd(struct rusage *ru, struct rusage_ext *rux, struct rusage *ru2,
997     struct rusage_ext *rux2)
998 {
999 
1000 	rux->rux_runtime += rux2->rux_runtime;
1001 	rux->rux_uticks += rux2->rux_uticks;
1002 	rux->rux_sticks += rux2->rux_sticks;
1003 	rux->rux_iticks += rux2->rux_iticks;
1004 	rux->rux_uu += rux2->rux_uu;
1005 	rux->rux_su += rux2->rux_su;
1006 	rux->rux_tu += rux2->rux_tu;
1007 	rucollect(ru, ru2);
1008 }
1009 
1010 /*
1011  * Aggregate tick counts into the proc's rusage_ext.
1012  */
1013 static void
1014 ruxagg_locked(struct rusage_ext *rux, struct thread *td)
1015 {
1016 
1017 	THREAD_LOCK_ASSERT(td, MA_OWNED);
1018 	PROC_SLOCK_ASSERT(td->td_proc, MA_OWNED);
1019 	rux->rux_runtime += td->td_incruntime;
1020 	rux->rux_uticks += td->td_uticks;
1021 	rux->rux_sticks += td->td_sticks;
1022 	rux->rux_iticks += td->td_iticks;
1023 }
1024 
1025 void
1026 ruxagg(struct proc *p, struct thread *td)
1027 {
1028 
1029 	thread_lock(td);
1030 	ruxagg_locked(&p->p_rux, td);
1031 	ruxagg_locked(&td->td_rux, td);
1032 	td->td_incruntime = 0;
1033 	td->td_uticks = 0;
1034 	td->td_iticks = 0;
1035 	td->td_sticks = 0;
1036 	thread_unlock(td);
1037 }
1038 
1039 /*
1040  * Update the rusage_ext structure and fetch a valid aggregate rusage
1041  * for proc p if storage for one is supplied.
1042  */
1043 void
1044 rufetch(struct proc *p, struct rusage *ru)
1045 {
1046 	struct thread *td;
1047 
1048 	PROC_SLOCK_ASSERT(p, MA_OWNED);
1049 
1050 	*ru = p->p_ru;
1051 	if (p->p_numthreads > 0)  {
1052 		FOREACH_THREAD_IN_PROC(p, td) {
1053 			ruxagg(p, td);
1054 			rucollect(ru, &td->td_ru);
1055 		}
1056 	}
1057 }
1058 
1059 /*
1060  * Atomically perform a rufetch and a calcru together.
1061  * Consumers, can safely assume the calcru is executed only once
1062  * rufetch is completed.
1063  */
1064 void
1065 rufetchcalc(struct proc *p, struct rusage *ru, struct timeval *up,
1066     struct timeval *sp)
1067 {
1068 
1069 	PROC_SLOCK(p);
1070 	rufetch(p, ru);
1071 	calcru(p, up, sp);
1072 	PROC_SUNLOCK(p);
1073 }
1074 
1075 /*
1076  * Allocate a new resource limits structure and initialize its
1077  * reference count and mutex pointer.
1078  */
1079 struct plimit *
1080 lim_alloc()
1081 {
1082 	struct plimit *limp;
1083 
1084 	limp = malloc(sizeof(struct plimit), M_PLIMIT, M_WAITOK);
1085 	refcount_init(&limp->pl_refcnt, 1);
1086 	return (limp);
1087 }
1088 
1089 struct plimit *
1090 lim_hold(limp)
1091 	struct plimit *limp;
1092 {
1093 
1094 	refcount_acquire(&limp->pl_refcnt);
1095 	return (limp);
1096 }
1097 
1098 void
1099 lim_fork(struct proc *p1, struct proc *p2)
1100 {
1101 	p2->p_limit = lim_hold(p1->p_limit);
1102 	callout_init_mtx(&p2->p_limco, &p2->p_mtx, 0);
1103 	if (p1->p_cpulimit != RLIM_INFINITY)
1104 		callout_reset(&p2->p_limco, hz, lim_cb, p2);
1105 }
1106 
1107 void
1108 lim_free(limp)
1109 	struct plimit *limp;
1110 {
1111 
1112 	KASSERT(limp->pl_refcnt > 0, ("plimit refcnt underflow"));
1113 	if (refcount_release(&limp->pl_refcnt))
1114 		free((void *)limp, M_PLIMIT);
1115 }
1116 
1117 /*
1118  * Make a copy of the plimit structure.
1119  * We share these structures copy-on-write after fork.
1120  */
1121 void
1122 lim_copy(dst, src)
1123 	struct plimit *dst, *src;
1124 {
1125 
1126 	KASSERT(dst->pl_refcnt == 1, ("lim_copy to shared limit"));
1127 	bcopy(src->pl_rlimit, dst->pl_rlimit, sizeof(src->pl_rlimit));
1128 }
1129 
1130 /*
1131  * Return the hard limit for a particular system resource.  The
1132  * which parameter specifies the index into the rlimit array.
1133  */
1134 rlim_t
1135 lim_max(struct proc *p, int which)
1136 {
1137 	struct rlimit rl;
1138 
1139 	lim_rlimit(p, which, &rl);
1140 	return (rl.rlim_max);
1141 }
1142 
1143 /*
1144  * Return the current (soft) limit for a particular system resource.
1145  * The which parameter which specifies the index into the rlimit array
1146  */
1147 rlim_t
1148 lim_cur(struct proc *p, int which)
1149 {
1150 	struct rlimit rl;
1151 
1152 	lim_rlimit(p, which, &rl);
1153 	return (rl.rlim_cur);
1154 }
1155 
1156 /*
1157  * Return a copy of the entire rlimit structure for the system limit
1158  * specified by 'which' in the rlimit structure pointed to by 'rlp'.
1159  */
1160 void
1161 lim_rlimit(struct proc *p, int which, struct rlimit *rlp)
1162 {
1163 
1164 	PROC_LOCK_ASSERT(p, MA_OWNED);
1165 	KASSERT(which >= 0 && which < RLIM_NLIMITS,
1166 	    ("request for invalid resource limit"));
1167 	*rlp = p->p_limit->pl_rlimit[which];
1168 	if (p->p_sysent->sv_fixlimit != NULL)
1169 		p->p_sysent->sv_fixlimit(rlp, which);
1170 }
1171 
1172 /*
1173  * Find the uidinfo structure for a uid.  This structure is used to
1174  * track the total resource consumption (process count, socket buffer
1175  * size, etc.) for the uid and impose limits.
1176  */
1177 void
1178 uihashinit()
1179 {
1180 
1181 	uihashtbl = hashinit(maxproc / 16, M_UIDINFO, &uihash);
1182 	rw_init(&uihashtbl_lock, "uidinfo hash");
1183 }
1184 
1185 /*
1186  * Look up a uidinfo struct for the parameter uid.
1187  * uihashtbl_lock must be locked.
1188  */
1189 static struct uidinfo *
1190 uilookup(uid)
1191 	uid_t uid;
1192 {
1193 	struct uihashhead *uipp;
1194 	struct uidinfo *uip;
1195 
1196 	rw_assert(&uihashtbl_lock, RA_LOCKED);
1197 	uipp = UIHASH(uid);
1198 	LIST_FOREACH(uip, uipp, ui_hash)
1199 		if (uip->ui_uid == uid)
1200 			break;
1201 
1202 	return (uip);
1203 }
1204 
1205 /*
1206  * Find or allocate a struct uidinfo for a particular uid.
1207  * Increase refcount on uidinfo struct returned.
1208  * uifree() should be called on a struct uidinfo when released.
1209  */
1210 struct uidinfo *
1211 uifind(uid)
1212 	uid_t uid;
1213 {
1214 	struct uidinfo *old_uip, *uip;
1215 
1216 	rw_rlock(&uihashtbl_lock);
1217 	uip = uilookup(uid);
1218 	if (uip == NULL) {
1219 		rw_runlock(&uihashtbl_lock);
1220 		uip = malloc(sizeof(*uip), M_UIDINFO, M_WAITOK | M_ZERO);
1221 		rw_wlock(&uihashtbl_lock);
1222 		/*
1223 		 * There's a chance someone created our uidinfo while we
1224 		 * were in malloc and not holding the lock, so we have to
1225 		 * make sure we don't insert a duplicate uidinfo.
1226 		 */
1227 		if ((old_uip = uilookup(uid)) != NULL) {
1228 			/* Someone else beat us to it. */
1229 			free(uip, M_UIDINFO);
1230 			uip = old_uip;
1231 		} else {
1232 			refcount_init(&uip->ui_ref, 0);
1233 			uip->ui_uid = uid;
1234 			mtx_init(&uip->ui_vmsize_mtx, "ui_vmsize", NULL,
1235 			    MTX_DEF);
1236 			LIST_INSERT_HEAD(UIHASH(uid), uip, ui_hash);
1237 		}
1238 	}
1239 	uihold(uip);
1240 	rw_unlock(&uihashtbl_lock);
1241 	return (uip);
1242 }
1243 
1244 /*
1245  * Place another refcount on a uidinfo struct.
1246  */
1247 void
1248 uihold(uip)
1249 	struct uidinfo *uip;
1250 {
1251 
1252 	refcount_acquire(&uip->ui_ref);
1253 }
1254 
1255 /*-
1256  * Since uidinfo structs have a long lifetime, we use an
1257  * opportunistic refcounting scheme to avoid locking the lookup hash
1258  * for each release.
1259  *
1260  * If the refcount hits 0, we need to free the structure,
1261  * which means we need to lock the hash.
1262  * Optimal case:
1263  *   After locking the struct and lowering the refcount, if we find
1264  *   that we don't need to free, simply unlock and return.
1265  * Suboptimal case:
1266  *   If refcount lowering results in need to free, bump the count
1267  *   back up, lose the lock and acquire the locks in the proper
1268  *   order to try again.
1269  */
1270 void
1271 uifree(uip)
1272 	struct uidinfo *uip;
1273 {
1274 	int old;
1275 
1276 	/* Prepare for optimal case. */
1277 	old = uip->ui_ref;
1278 	if (old > 1 && atomic_cmpset_int(&uip->ui_ref, old, old - 1))
1279 		return;
1280 
1281 	/* Prepare for suboptimal case. */
1282 	rw_wlock(&uihashtbl_lock);
1283 	if (refcount_release(&uip->ui_ref)) {
1284 		LIST_REMOVE(uip, ui_hash);
1285 		rw_wunlock(&uihashtbl_lock);
1286 		if (uip->ui_sbsize != 0)
1287 			printf("freeing uidinfo: uid = %d, sbsize = %ld\n",
1288 			    uip->ui_uid, uip->ui_sbsize);
1289 		if (uip->ui_proccnt != 0)
1290 			printf("freeing uidinfo: uid = %d, proccnt = %ld\n",
1291 			    uip->ui_uid, uip->ui_proccnt);
1292 		if (uip->ui_vmsize != 0)
1293 			printf("freeing uidinfo: uid = %d, swapuse = %lld\n",
1294 			    uip->ui_uid, (unsigned long long)uip->ui_vmsize);
1295 		mtx_destroy(&uip->ui_vmsize_mtx);
1296 		free(uip, M_UIDINFO);
1297 		return;
1298 	}
1299 	/*
1300 	 * Someone added a reference between atomic_cmpset_int() and
1301 	 * rw_wlock(&uihashtbl_lock).
1302 	 */
1303 	rw_wunlock(&uihashtbl_lock);
1304 }
1305 
1306 /*
1307  * Change the count associated with number of processes
1308  * a given user is using.  When 'max' is 0, don't enforce a limit
1309  */
1310 int
1311 chgproccnt(uip, diff, max)
1312 	struct	uidinfo	*uip;
1313 	int	diff;
1314 	rlim_t	max;
1315 {
1316 
1317 	/* Don't allow them to exceed max, but allow subtraction. */
1318 	if (diff > 0 && max != 0) {
1319 		if (atomic_fetchadd_long(&uip->ui_proccnt, (long)diff) + diff > max) {
1320 			atomic_subtract_long(&uip->ui_proccnt, (long)diff);
1321 			return (0);
1322 		}
1323 	} else {
1324 		atomic_add_long(&uip->ui_proccnt, (long)diff);
1325 		if (uip->ui_proccnt < 0)
1326 			printf("negative proccnt for uid = %d\n", uip->ui_uid);
1327 	}
1328 	return (1);
1329 }
1330 
1331 /*
1332  * Change the total socket buffer size a user has used.
1333  */
1334 int
1335 chgsbsize(uip, hiwat, to, max)
1336 	struct	uidinfo	*uip;
1337 	u_int  *hiwat;
1338 	u_int	to;
1339 	rlim_t	max;
1340 {
1341 	int diff;
1342 
1343 	diff = to - *hiwat;
1344 	if (diff > 0) {
1345 		if (atomic_fetchadd_long(&uip->ui_sbsize, (long)diff) + diff > max) {
1346 			atomic_subtract_long(&uip->ui_sbsize, (long)diff);
1347 			return (0);
1348 		}
1349 	} else {
1350 		atomic_add_long(&uip->ui_sbsize, (long)diff);
1351 		if (uip->ui_sbsize < 0)
1352 			printf("negative sbsize for uid = %d\n", uip->ui_uid);
1353 	}
1354 	*hiwat = to;
1355 	return (1);
1356 }
1357 
1358 /*
1359  * Change the count associated with number of pseudo-terminals
1360  * a given user is using.  When 'max' is 0, don't enforce a limit
1361  */
1362 int
1363 chgptscnt(uip, diff, max)
1364 	struct	uidinfo	*uip;
1365 	int	diff;
1366 	rlim_t	max;
1367 {
1368 
1369 	/* Don't allow them to exceed max, but allow subtraction. */
1370 	if (diff > 0 && max != 0) {
1371 		if (atomic_fetchadd_long(&uip->ui_ptscnt, (long)diff) + diff > max) {
1372 			atomic_subtract_long(&uip->ui_ptscnt, (long)diff);
1373 			return (0);
1374 		}
1375 	} else {
1376 		atomic_add_long(&uip->ui_ptscnt, (long)diff);
1377 		if (uip->ui_ptscnt < 0)
1378 			printf("negative ptscnt for uid = %d\n", uip->ui_uid);
1379 	}
1380 	return (1);
1381 }
1382