xref: /freebsd/sys/kern/kern_resource.c (revision afe61c15161c324a7af299a9b8457aba5afc92db)
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  */
40 
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/kernel.h>
44 #include <sys/file.h>
45 #include <sys/resourcevar.h>
46 #include <sys/malloc.h>
47 #include <sys/proc.h>
48 
49 #include <vm/vm.h>
50 
51 /*
52  * Resource controls and accounting.
53  */
54 
55 struct getpriority_args {
56 	int	which;
57 	int	who;
58 };
59 int
60 getpriority(curp, uap, retval)
61 	struct proc *curp;
62 	register struct getpriority_args *uap;
63 	int *retval;
64 {
65 	register struct proc *p;
66 	register int low = PRIO_MAX + 1;
67 
68 	switch (uap->which) {
69 
70 	case PRIO_PROCESS:
71 		if (uap->who == 0)
72 			p = curp;
73 		else
74 			p = pfind(uap->who);
75 		if (p == 0)
76 			break;
77 		low = p->p_nice;
78 		break;
79 
80 	case PRIO_PGRP: {
81 		register struct pgrp *pg;
82 
83 		if (uap->who == 0)
84 			pg = curp->p_pgrp;
85 		else if ((pg = pgfind(uap->who)) == NULL)
86 			break;
87 		for (p = pg->pg_mem; p != NULL; p = p->p_pgrpnxt) {
88 			if (p->p_nice < low)
89 				low = p->p_nice;
90 		}
91 		break;
92 	}
93 
94 	case PRIO_USER:
95 		if (uap->who == 0)
96 			uap->who = curp->p_ucred->cr_uid;
97 		for (p = (struct proc *)allproc; p != NULL; p = p->p_next) {
98 			if (p->p_ucred->cr_uid == uap->who &&
99 			    p->p_nice < low)
100 				low = p->p_nice;
101 		}
102 		break;
103 
104 	default:
105 		return (EINVAL);
106 	}
107 	if (low == PRIO_MAX + 1)
108 		return (ESRCH);
109 	*retval = low;
110 	return (0);
111 }
112 
113 struct setpriority_args {
114 	int	which;
115 	int	who;
116 	int	prio;
117 };
118 /* ARGSUSED */
119 int
120 setpriority(curp, uap, retval)
121 	struct proc *curp;
122 	register struct setpriority_args *uap;
123 	int *retval;
124 {
125 	register struct proc *p;
126 	int found = 0, error = 0;
127 
128 	switch (uap->which) {
129 
130 	case PRIO_PROCESS:
131 		if (uap->who == 0)
132 			p = curp;
133 		else
134 			p = pfind(uap->who);
135 		if (p == 0)
136 			break;
137 		error = donice(curp, p, uap->prio);
138 		found++;
139 		break;
140 
141 	case PRIO_PGRP: {
142 		register struct pgrp *pg;
143 
144 		if (uap->who == 0)
145 			pg = curp->p_pgrp;
146 		else if ((pg = pgfind(uap->who)) == NULL)
147 			break;
148 		for (p = pg->pg_mem; p != NULL; p = p->p_pgrpnxt) {
149 			error = donice(curp, p, uap->prio);
150 			found++;
151 		}
152 		break;
153 	}
154 
155 	case PRIO_USER:
156 		if (uap->who == 0)
157 			uap->who = curp->p_ucred->cr_uid;
158 		for (p = (struct proc *)allproc; p != NULL; p = p->p_next)
159 			if (p->p_ucred->cr_uid == uap->who) {
160 				error = donice(curp, p, uap->prio);
161 				found++;
162 			}
163 		break;
164 
165 	default:
166 		return (EINVAL);
167 	}
168 	if (found == 0)
169 		return (ESRCH);
170 	return (error);
171 }
172 
173 int
174 donice(curp, chgp, n)
175 	register struct proc *curp, *chgp;
176 	register int n;
177 {
178 	register struct pcred *pcred = curp->p_cred;
179 
180 	if (pcred->pc_ucred->cr_uid && pcred->p_ruid &&
181 	    pcred->pc_ucred->cr_uid != chgp->p_ucred->cr_uid &&
182 	    pcred->p_ruid != chgp->p_ucred->cr_uid)
183 		return (EPERM);
184 	if (n > PRIO_MAX)
185 		n = PRIO_MAX;
186 	if (n < PRIO_MIN)
187 		n = PRIO_MIN;
188 	if (n < chgp->p_nice && suser(pcred->pc_ucred, &curp->p_acflag))
189 		return (EACCES);
190 	chgp->p_nice = n;
191 	(void)resetpriority(chgp);
192 	return (0);
193 }
194 
195 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
196 struct setrlimit_args {
197 	u_int	which;
198 	struct	orlimit *lim;
199 };
200 /* ARGSUSED */
201 int
202 osetrlimit(p, uap, retval)
203 	struct proc *p;
204 	register struct setrlimit_args *uap;
205 	int *retval;
206 {
207 	struct orlimit olim;
208 	struct rlimit lim;
209 	int error;
210 
211 	if (error =
212 	    copyin((caddr_t)uap->lim, (caddr_t)&olim, sizeof (struct orlimit)))
213 		return (error);
214 	lim.rlim_cur = olim.rlim_cur;
215 	lim.rlim_max = olim.rlim_max;
216 	return (dosetrlimit(p, uap->which, &lim));
217 }
218 
219 struct getrlimit_args {
220 	u_int	which;
221 	struct	orlimit *rlp;
222 };
223 /* ARGSUSED */
224 int
225 ogetrlimit(p, uap, retval)
226 	struct proc *p;
227 	register struct getrlimit_args *uap;
228 	int *retval;
229 {
230 	struct orlimit olim;
231 
232 	if (uap->which >= RLIM_NLIMITS)
233 		return (EINVAL);
234 	olim.rlim_cur = p->p_rlimit[uap->which].rlim_cur;
235 	if (olim.rlim_cur == -1)
236 		olim.rlim_cur = 0x7fffffff;
237 	olim.rlim_max = p->p_rlimit[uap->which].rlim_max;
238 	if (olim.rlim_max == -1)
239 		olim.rlim_max = 0x7fffffff;
240 	return (copyout((caddr_t)&olim, (caddr_t)uap->rlp, sizeof(olim)));
241 }
242 #endif /* COMPAT_43 || COMPAT_SUNOS */
243 
244 struct __setrlimit_args {
245 	u_int	which;
246 	struct	rlimit *lim;
247 };
248 /* ARGSUSED */
249 int
250 setrlimit(p, uap, retval)
251 	struct proc *p;
252 	register struct __setrlimit_args *uap;
253 	int *retval;
254 {
255 	struct rlimit alim;
256 	int error;
257 
258 	if (error =
259 	    copyin((caddr_t)uap->lim, (caddr_t)&alim, sizeof (struct rlimit)))
260 		return (error);
261 	return (dosetrlimit(p, uap->which, &alim));
262 }
263 
264 int
265 dosetrlimit(p, which, limp)
266 	struct proc *p;
267 	u_int which;
268 	struct rlimit *limp;
269 {
270 	register struct rlimit *alimp;
271 	int error;
272 
273 	if (which >= RLIM_NLIMITS)
274 		return (EINVAL);
275 	alimp = &p->p_rlimit[which];
276 	if (limp->rlim_cur > alimp->rlim_max ||
277 	    limp->rlim_max > alimp->rlim_max)
278 		if (error = suser(p->p_ucred, &p->p_acflag))
279 			return (error);
280 	if (limp->rlim_cur > limp->rlim_max)
281 		limp->rlim_cur = limp->rlim_max;
282 	if (p->p_limit->p_refcnt > 1 &&
283 	    (p->p_limit->p_lflags & PL_SHAREMOD) == 0) {
284 		p->p_limit->p_refcnt--;
285 		p->p_limit = limcopy(p->p_limit);
286 		alimp = &p->p_rlimit[which];
287 	}
288 
289 	switch (which) {
290 
291 	case RLIMIT_DATA:
292 		if (limp->rlim_cur > MAXDSIZ)
293 			limp->rlim_cur = MAXDSIZ;
294 		if (limp->rlim_max > MAXDSIZ)
295 			limp->rlim_max = MAXDSIZ;
296 		break;
297 
298 	case RLIMIT_STACK:
299 		if (limp->rlim_cur > MAXSSIZ)
300 			limp->rlim_cur = MAXSSIZ;
301 		if (limp->rlim_max > MAXSSIZ)
302 			limp->rlim_max = MAXSSIZ;
303 		/*
304 		 * Stack is allocated to the max at exec time with only
305 		 * "rlim_cur" bytes accessible.  If stack limit is going
306 		 * up make more accessible, if going down make inaccessible.
307 		 */
308 		if (limp->rlim_cur != alimp->rlim_cur) {
309 			vm_offset_t addr;
310 			vm_size_t size;
311 			vm_prot_t prot;
312 
313 			if (limp->rlim_cur > alimp->rlim_cur) {
314 				prot = VM_PROT_ALL;
315 				size = limp->rlim_cur - alimp->rlim_cur;
316 				addr = USRSTACK - limp->rlim_cur;
317 			} else {
318 				prot = VM_PROT_NONE;
319 				size = alimp->rlim_cur - limp->rlim_cur;
320 				addr = USRSTACK - alimp->rlim_cur;
321 			}
322 			addr = trunc_page(addr);
323 			size = round_page(size);
324 			(void) vm_map_protect(&p->p_vmspace->vm_map,
325 					      addr, addr+size, prot, FALSE);
326 		}
327 		break;
328 
329 	case RLIMIT_NOFILE:
330 		if (limp->rlim_cur > maxfiles)
331 			limp->rlim_cur = maxfiles;
332 		if (limp->rlim_max > maxfiles)
333 			limp->rlim_max = maxfiles;
334 		break;
335 
336 	case RLIMIT_NPROC:
337 		if (limp->rlim_cur > maxproc)
338 			limp->rlim_cur = maxproc;
339 		if (limp->rlim_max > maxproc)
340 			limp->rlim_max = maxproc;
341 		break;
342 	}
343 	*alimp = *limp;
344 	return (0);
345 }
346 
347 struct __getrlimit_args {
348 	u_int	which;
349 	struct	rlimit *rlp;
350 };
351 /* ARGSUSED */
352 int
353 getrlimit(p, uap, retval)
354 	struct proc *p;
355 	register struct __getrlimit_args *uap;
356 	int *retval;
357 {
358 
359 	if (uap->which >= RLIM_NLIMITS)
360 		return (EINVAL);
361 	return (copyout((caddr_t)&p->p_rlimit[uap->which], (caddr_t)uap->rlp,
362 	    sizeof (struct rlimit)));
363 }
364 
365 /*
366  * Transform the running time and tick information in proc p into user,
367  * system, and interrupt time usage.
368  */
369 void
370 calcru(p, up, sp, ip)
371 	register struct proc *p;
372 	register struct timeval *up;
373 	register struct timeval *sp;
374 	register struct timeval *ip;
375 {
376 	register u_quad_t u, st, ut, it, tot;
377 	register u_long sec, usec;
378 	register int s;
379 	struct timeval tv;
380 
381 	s = splstatclock();
382 	st = p->p_sticks;
383 	ut = p->p_uticks;
384 	it = p->p_iticks;
385 	splx(s);
386 
387 	tot = st + ut + it;
388 	if (tot == 0) {
389 		up->tv_sec = up->tv_usec = 0;
390 		sp->tv_sec = sp->tv_usec = 0;
391 		if (ip != NULL)
392 			ip->tv_sec = ip->tv_usec = 0;
393 		return;
394 	}
395 
396 	sec = p->p_rtime.tv_sec;
397 	usec = p->p_rtime.tv_usec;
398 	if (p == curproc) {
399 		/*
400 		 * Adjust for the current time slice.  This is actually fairly
401 		 * important since the error here is on the order of a time
402 		 * quantum, which is much greater than the sampling error.
403 		 */
404 		microtime(&tv);
405 		sec += tv.tv_sec - runtime.tv_sec;
406 		usec += tv.tv_usec - runtime.tv_usec;
407 	}
408 	u = sec * 1000000 + usec;
409 	st = (u * st) / tot;
410 	sp->tv_sec = st / 1000000;
411 	sp->tv_usec = st % 1000000;
412 	ut = (u * ut) / tot;
413 	up->tv_sec = ut / 1000000;
414 	up->tv_usec = ut % 1000000;
415 	if (ip != NULL) {
416 		it = (u * it) / tot;
417 		ip->tv_sec = it / 1000000;
418 		ip->tv_usec = it % 1000000;
419 	}
420 }
421 
422 struct getrusage_args {
423 	int	who;
424 	struct	rusage *rusage;
425 };
426 /* ARGSUSED */
427 int
428 getrusage(p, uap, retval)
429 	register struct proc *p;
430 	register struct getrusage_args *uap;
431 	int *retval;
432 {
433 	register struct rusage *rup;
434 
435 	switch (uap->who) {
436 
437 	case RUSAGE_SELF:
438 		rup = &p->p_stats->p_ru;
439 		calcru(p, &rup->ru_utime, &rup->ru_stime, NULL);
440 		break;
441 
442 	case RUSAGE_CHILDREN:
443 		rup = &p->p_stats->p_cru;
444 		break;
445 
446 	default:
447 		return (EINVAL);
448 	}
449 	return (copyout((caddr_t)rup, (caddr_t)uap->rusage,
450 	    sizeof (struct rusage)));
451 }
452 
453 void
454 ruadd(ru, ru2)
455 	register struct rusage *ru, *ru2;
456 {
457 	register long *ip, *ip2;
458 	register int i;
459 
460 	timevaladd(&ru->ru_utime, &ru2->ru_utime);
461 	timevaladd(&ru->ru_stime, &ru2->ru_stime);
462 	if (ru->ru_maxrss < ru2->ru_maxrss)
463 		ru->ru_maxrss = ru2->ru_maxrss;
464 	ip = &ru->ru_first; ip2 = &ru2->ru_first;
465 	for (i = &ru->ru_last - &ru->ru_first; i >= 0; i--)
466 		*ip++ += *ip2++;
467 }
468 
469 /*
470  * Make a copy of the plimit structure.
471  * We share these structures copy-on-write after fork,
472  * and copy when a limit is changed.
473  */
474 struct plimit *
475 limcopy(lim)
476 	struct plimit *lim;
477 {
478 	register struct plimit *copy;
479 
480 	MALLOC(copy, struct plimit *, sizeof(struct plimit),
481 	    M_SUBPROC, M_WAITOK);
482 	bcopy(lim->pl_rlimit, copy->pl_rlimit,
483 	    sizeof(struct rlimit) * RLIM_NLIMITS);
484 	copy->p_lflags = 0;
485 	copy->p_refcnt = 1;
486 	return (copy);
487 }
488