xref: /netbsd-src/sys/kern/kern_resource.c (revision 27578b9aac214cc7796ead81dcc5427e79d5f2a0)
1 /*	$NetBSD: kern_resource.c,v 1.60 2001/02/06 19:54:43 eeh Exp $	*/
2 
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. All advertising materials mentioning features or use of this software
21  *    must display the following acknowledgement:
22  *	This product includes software developed by the University of
23  *	California, Berkeley and its contributors.
24  * 4. Neither the name of the University nor the names of its contributors
25  *    may be used to endorse or promote products derived from this software
26  *    without specific prior written permission.
27  *
28  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38  * SUCH DAMAGE.
39  *
40  *	@(#)kern_resource.c	8.8 (Berkeley) 2/14/95
41  */
42 
43 #include <sys/param.h>
44 #include <sys/systm.h>
45 #include <sys/kernel.h>
46 #include <sys/file.h>
47 #include <sys/resourcevar.h>
48 #include <sys/malloc.h>
49 #include <sys/pool.h>
50 #include <sys/proc.h>
51 
52 #include <sys/mount.h>
53 #include <sys/syscallargs.h>
54 
55 #include <uvm/uvm_extern.h>
56 
57 /*
58  * Maximum process data and stack limits.
59  * They are variables so they are patchable.
60  *
61  * XXXX Do we really need them to be patchable?
62  */
63 rlim_t maxdmap = MAXDSIZ;
64 rlim_t maxsmap = MAXSSIZ;
65 
66 /*
67  * Resource controls and accounting.
68  */
69 
70 int
71 sys_getpriority(curp, v, retval)
72 	struct proc *curp;
73 	void *v;
74 	register_t *retval;
75 {
76 	struct sys_getpriority_args /* {
77 		syscallarg(int) which;
78 		syscallarg(int) who;
79 	} */ *uap = v;
80 	struct proc *p;
81 	int low = NZERO + PRIO_MAX + 1;
82 
83 	switch (SCARG(uap, which)) {
84 
85 	case PRIO_PROCESS:
86 		if (SCARG(uap, who) == 0)
87 			p = curp;
88 		else
89 			p = pfind(SCARG(uap, who));
90 		if (p == 0)
91 			break;
92 		low = p->p_nice;
93 		break;
94 
95 	case PRIO_PGRP: {
96 		struct pgrp *pg;
97 
98 		if (SCARG(uap, who) == 0)
99 			pg = curp->p_pgrp;
100 		else if ((pg = pgfind(SCARG(uap, who))) == NULL)
101 			break;
102 		for (p = pg->pg_members.lh_first; p != 0;
103 		     p = p->p_pglist.le_next) {
104 			if (p->p_nice < low)
105 				low = p->p_nice;
106 		}
107 		break;
108 	}
109 
110 	case PRIO_USER:
111 		if (SCARG(uap, who) == 0)
112 			SCARG(uap, who) = curp->p_ucred->cr_uid;
113 		proclist_lock_read();
114 		for (p = allproc.lh_first; p != 0; p = p->p_list.le_next)
115 			if (p->p_ucred->cr_uid == SCARG(uap, who) &&
116 			    p->p_nice < low)
117 				low = p->p_nice;
118 		proclist_unlock_read();
119 		break;
120 
121 	default:
122 		return (EINVAL);
123 	}
124 	if (low == NZERO + PRIO_MAX + 1)
125 		return (ESRCH);
126 	*retval = low - NZERO;
127 	return (0);
128 }
129 
130 /* ARGSUSED */
131 int
132 sys_setpriority(curp, v, retval)
133 	struct proc *curp;
134 	void *v;
135 	register_t *retval;
136 {
137 	struct sys_setpriority_args /* {
138 		syscallarg(int) which;
139 		syscallarg(int) who;
140 		syscallarg(int) prio;
141 	} */ *uap = v;
142 	struct proc *p;
143 	int found = 0, error = 0;
144 
145 	switch (SCARG(uap, which)) {
146 
147 	case PRIO_PROCESS:
148 		if (SCARG(uap, who) == 0)
149 			p = curp;
150 		else
151 			p = pfind(SCARG(uap, who));
152 		if (p == 0)
153 			break;
154 		error = donice(curp, p, SCARG(uap, prio));
155 		found++;
156 		break;
157 
158 	case PRIO_PGRP: {
159 		struct pgrp *pg;
160 
161 		if (SCARG(uap, who) == 0)
162 			pg = curp->p_pgrp;
163 		else if ((pg = pgfind(SCARG(uap, who))) == NULL)
164 			break;
165 		for (p = pg->pg_members.lh_first; p != 0;
166 		    p = p->p_pglist.le_next) {
167 			error = donice(curp, p, SCARG(uap, prio));
168 			found++;
169 		}
170 		break;
171 	}
172 
173 	case PRIO_USER:
174 		if (SCARG(uap, who) == 0)
175 			SCARG(uap, who) = curp->p_ucred->cr_uid;
176 		proclist_lock_read();
177 		for (p = allproc.lh_first; p != 0; p = p->p_list.le_next)
178 			if (p->p_ucred->cr_uid == SCARG(uap, who)) {
179 				error = donice(curp, p, SCARG(uap, prio));
180 				found++;
181 			}
182 		proclist_unlock_read();
183 		break;
184 
185 	default:
186 		return (EINVAL);
187 	}
188 	if (found == 0)
189 		return (ESRCH);
190 	return (error);
191 }
192 
193 int
194 donice(curp, chgp, n)
195 	struct proc *curp, *chgp;
196 	int n;
197 {
198 	struct pcred *pcred = curp->p_cred;
199 	int s;
200 
201 	if (pcred->pc_ucred->cr_uid && pcred->p_ruid &&
202 	    pcred->pc_ucred->cr_uid != chgp->p_ucred->cr_uid &&
203 	    pcred->p_ruid != chgp->p_ucred->cr_uid)
204 		return (EPERM);
205 	if (n > PRIO_MAX)
206 		n = PRIO_MAX;
207 	if (n < PRIO_MIN)
208 		n = PRIO_MIN;
209 	n += NZERO;
210 	if (n < chgp->p_nice && suser(pcred->pc_ucred, &curp->p_acflag))
211 		return (EACCES);
212 	chgp->p_nice = n;
213 	SCHED_LOCK(s);
214 	(void)resetpriority(chgp);
215 	SCHED_UNLOCK(s);
216 	return (0);
217 }
218 
219 /* ARGSUSED */
220 int
221 sys_setrlimit(p, v, retval)
222 	struct proc *p;
223 	void *v;
224 	register_t *retval;
225 {
226 	struct sys_setrlimit_args /* {
227 		syscallarg(int) which;
228 		syscallarg(const struct rlimit *) rlp;
229 	} */ *uap = v;
230 	int which = SCARG(uap, which);
231 	struct rlimit alim;
232 	int error;
233 
234 	error = copyin(SCARG(uap, rlp), &alim, sizeof(struct rlimit));
235 	if (error)
236 		return (error);
237 	return (dosetrlimit(p, p->p_cred, which, &alim));
238 }
239 
240 int
241 dosetrlimit(p, cred, which, limp)
242 	struct proc *p;
243 	struct  pcred *cred;
244 	int which;
245 	struct rlimit *limp;
246 {
247 	struct rlimit *alimp;
248 	struct plimit *newplim;
249 	int error;
250 
251 	if ((u_int)which >= RLIM_NLIMITS)
252 		return (EINVAL);
253 
254 	if (limp->rlim_cur < 0 || limp->rlim_max < 0)
255 		return (EINVAL);
256 
257 	alimp = &p->p_rlimit[which];
258 	/* if we don't change the value, no need to limcopy() */
259 	if (limp->rlim_cur == alimp->rlim_cur &&
260 	    limp->rlim_max == alimp->rlim_max)
261 		return 0;
262 
263 	if (limp->rlim_cur > alimp->rlim_max ||
264 	    limp->rlim_max > alimp->rlim_max)
265 		if ((error = suser(cred->pc_ucred, &p->p_acflag)) != 0)
266 			return (error);
267 	if (limp->rlim_cur > limp->rlim_max)
268 		limp->rlim_cur = limp->rlim_max;
269 	if (p->p_limit->p_refcnt > 1 &&
270 	    (p->p_limit->p_lflags & PL_SHAREMOD) == 0) {
271 		newplim = limcopy(p->p_limit);
272 		limfree(p->p_limit);
273 		p->p_limit = newplim;
274 		alimp = &p->p_rlimit[which];
275 	}
276 
277 	switch (which) {
278 
279 	case RLIMIT_DATA:
280 		if (limp->rlim_cur > maxdmap)
281 			limp->rlim_cur = maxdmap;
282 		if (limp->rlim_max > maxdmap)
283 			limp->rlim_max = maxdmap;
284 		break;
285 
286 	case RLIMIT_STACK:
287 		if (limp->rlim_cur > maxsmap)
288 			limp->rlim_cur = maxsmap;
289 		if (limp->rlim_max > maxsmap)
290 			limp->rlim_max = maxsmap;
291 
292 		/*
293 		 * Stack is allocated to the max at exec time with
294 		 * only "rlim_cur" bytes accessible (In other words,
295 		 * allocates stack dividing two contiguous regions at
296 		 * "rlim_cur" bytes boundary).
297 		 *
298 		 * Since allocation is done in terms of page, roundup
299 		 * "rlim_cur" (otherwise, contiguous regions
300 		 * overlap).  If stack limit is going up make more
301 		 * accessible, if going down make inaccessible.
302 		 */
303 		limp->rlim_cur = round_page(limp->rlim_cur);
304 		if (limp->rlim_cur != alimp->rlim_cur) {
305 			vaddr_t addr;
306 			vsize_t size;
307 			vm_prot_t prot;
308 
309 			if (limp->rlim_cur > alimp->rlim_cur) {
310 				prot = VM_PROT_ALL;
311 				size = limp->rlim_cur - alimp->rlim_cur;
312 				addr = USRSTACK - limp->rlim_cur;
313 			} else {
314 				prot = VM_PROT_NONE;
315 				size = alimp->rlim_cur - limp->rlim_cur;
316 				addr = USRSTACK - alimp->rlim_cur;
317 			}
318 			(void) uvm_map_protect(&p->p_vmspace->vm_map,
319 					      addr, addr+size, prot, FALSE);
320 		}
321 		break;
322 
323 	case RLIMIT_NOFILE:
324 		if (limp->rlim_cur > maxfiles)
325 			limp->rlim_cur = maxfiles;
326 		if (limp->rlim_max > maxfiles)
327 			limp->rlim_max = maxfiles;
328 		break;
329 
330 	case RLIMIT_NPROC:
331 		if (limp->rlim_cur > maxproc)
332 			limp->rlim_cur = maxproc;
333 		if (limp->rlim_max > maxproc)
334 			limp->rlim_max = maxproc;
335 		break;
336 	}
337 	*alimp = *limp;
338 	return (0);
339 }
340 
341 /* ARGSUSED */
342 int
343 sys_getrlimit(p, v, retval)
344 	struct proc *p;
345 	void *v;
346 	register_t *retval;
347 {
348 	struct sys_getrlimit_args /* {
349 		syscallarg(int) which;
350 		syscallarg(struct rlimit *) rlp;
351 	} */ *uap = v;
352 	int which = SCARG(uap, which);
353 
354 	if ((u_int)which >= RLIM_NLIMITS)
355 		return (EINVAL);
356 	return (copyout(&p->p_rlimit[which], SCARG(uap, rlp),
357 	    sizeof(struct rlimit)));
358 }
359 
360 /*
361  * Transform the running time and tick information in proc p into user,
362  * system, and interrupt time usage.
363  */
364 void
365 calcru(p, up, sp, ip)
366 	struct proc *p;
367 	struct timeval *up;
368 	struct timeval *sp;
369 	struct timeval *ip;
370 {
371 	u_quad_t u, st, ut, it, tot;
372 	long sec, usec;
373 	int s;
374 	struct timeval tv;
375 
376 	s = splstatclock();
377 	st = p->p_sticks;
378 	ut = p->p_uticks;
379 	it = p->p_iticks;
380 	splx(s);
381 
382 	tot = st + ut + it;
383 	if (tot == 0) {
384 		up->tv_sec = up->tv_usec = 0;
385 		sp->tv_sec = sp->tv_usec = 0;
386 		if (ip != NULL)
387 			ip->tv_sec = ip->tv_usec = 0;
388 		return;
389 	}
390 
391 	sec = p->p_rtime.tv_sec;
392 	usec = p->p_rtime.tv_usec;
393 	if (p->p_stat == SONPROC) {
394 		struct schedstate_percpu *spc;
395 
396 		KDASSERT(p->p_cpu != NULL);
397 		spc = &p->p_cpu->ci_schedstate;
398 
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 - spc->spc_runtime.tv_sec;
406 		usec += tv.tv_usec - spc->spc_runtime.tv_usec;
407 	}
408 	u = (u_quad_t) 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 /* ARGSUSED */
423 int
424 sys_getrusage(p, v, retval)
425 	struct proc *p;
426 	void *v;
427 	register_t *retval;
428 {
429 	struct sys_getrusage_args /* {
430 		syscallarg(int) who;
431 		syscallarg(struct rusage *) rusage;
432 	} */ *uap = v;
433 	struct rusage *rup;
434 
435 	switch (SCARG(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(rup, SCARG(uap, rusage), sizeof(struct rusage)));
450 }
451 
452 void
453 ruadd(ru, ru2)
454 	struct rusage *ru, *ru2;
455 {
456 	long *ip, *ip2;
457 	int i;
458 
459 	timeradd(&ru->ru_utime, &ru2->ru_utime, &ru->ru_utime);
460 	timeradd(&ru->ru_stime, &ru2->ru_stime, &ru->ru_stime);
461 	if (ru->ru_maxrss < ru2->ru_maxrss)
462 		ru->ru_maxrss = ru2->ru_maxrss;
463 	ip = &ru->ru_first; ip2 = &ru2->ru_first;
464 	for (i = &ru->ru_last - &ru->ru_first; i >= 0; i--)
465 		*ip++ += *ip2++;
466 }
467 
468 /*
469  * Make a copy of the plimit structure.
470  * We share these structures copy-on-write after fork,
471  * and copy when a limit is changed.
472  */
473 struct plimit *
474 limcopy(lim)
475 	struct plimit *lim;
476 {
477 	struct plimit *newlim;
478 
479 	newlim = pool_get(&plimit_pool, PR_WAITOK);
480 	memcpy(newlim->pl_rlimit, lim->pl_rlimit,
481 	    sizeof(struct rlimit) * RLIM_NLIMITS);
482 	if (lim->pl_corename == defcorename) {
483 		newlim->pl_corename = defcorename;
484 	} else {
485 		newlim->pl_corename = malloc(strlen(lim->pl_corename)+1,
486 		    M_TEMP, M_WAITOK);
487 		strcpy(newlim->pl_corename, lim->pl_corename);
488 	}
489 	newlim->p_lflags = 0;
490 	newlim->p_refcnt = 1;
491 	return (newlim);
492 }
493 
494 void
495 limfree(lim)
496 	struct plimit *lim;
497 {
498 
499 	if (--lim->p_refcnt > 0)
500 		return;
501 #ifdef DIAGNOSTIC
502 	if (lim->p_refcnt < 0)
503 		panic("limfree");
504 #endif
505 	if (lim->pl_corename != defcorename)
506 		free(lim->pl_corename, M_TEMP);
507 	pool_put(&plimit_pool, lim);
508 }
509