xref: /openbsd-src/sys/kern/kern_resource.c (revision 636eb1092aad7ee44a83ea0cb1f71bba59f1bc3b)
1 /*	$OpenBSD: kern_resource.c,v 1.14 2001/06/27 04:49:44 art Exp $	*/
2 /*	$NetBSD: kern_resource.c,v 1.38 1996/10/23 07:19:38 matthias Exp $	*/
3 
4 /*-
5  * Copyright (c) 1982, 1986, 1991, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  * (c) UNIX System Laboratories, Inc.
8  * All or some portions of this file are derived from material licensed
9  * to the University of California by American Telephone and Telegraph
10  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
11  * the permission of UNIX System Laboratories, Inc.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  * 3. All advertising materials mentioning features or use of this software
22  *    must display the following acknowledgement:
23  *	This product includes software developed by the University of
24  *	California, Berkeley and its contributors.
25  * 4. Neither the name of the University nor the names of its contributors
26  *    may be used to endorse or promote products derived from this software
27  *    without specific prior written permission.
28  *
29  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
30  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
31  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
32  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
33  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
34  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
35  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
37  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
38  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39  * SUCH DAMAGE.
40  *
41  *	@(#)kern_resource.c	8.5 (Berkeley) 1/21/94
42  */
43 
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/kernel.h>
47 #include <sys/file.h>
48 #include <sys/resourcevar.h>
49 #include <sys/malloc.h>
50 #include <sys/proc.h>
51 
52 #include <sys/mount.h>
53 #include <sys/syscallargs.h>
54 
55 #include <vm/vm.h>
56 
57 #include <uvm/uvm_extern.h>
58 
59 /*
60  * Resource controls and accounting.
61  */
62 
63 int
64 sys_getpriority(curp, v, retval)
65 	struct proc *curp;
66 	void *v;
67 	register_t *retval;
68 {
69 	register struct sys_getpriority_args /* {
70 		syscallarg(int) which;
71 		syscallarg(int) who;
72 	} */ *uap = v;
73 	register struct proc *p;
74 	register int low = NZERO + PRIO_MAX + 1;
75 
76 	switch (SCARG(uap, which)) {
77 
78 	case PRIO_PROCESS:
79 		if (SCARG(uap, who) == 0)
80 			p = curp;
81 		else
82 			p = pfind(SCARG(uap, who));
83 		if (p == 0)
84 			break;
85 		low = p->p_nice;
86 		break;
87 
88 	case PRIO_PGRP: {
89 		register struct pgrp *pg;
90 
91 		if (SCARG(uap, who) == 0)
92 			pg = curp->p_pgrp;
93 		else if ((pg = pgfind(SCARG(uap, who))) == NULL)
94 			break;
95 		for (p = pg->pg_members.lh_first; p != 0; p = p->p_pglist.le_next) {
96 			if (p->p_nice < low)
97 				low = p->p_nice;
98 		}
99 		break;
100 	}
101 
102 	case PRIO_USER:
103 		if (SCARG(uap, who) == 0)
104 			SCARG(uap, who) = curp->p_ucred->cr_uid;
105 		for (p = LIST_FIRST(&allproc); p; p = LIST_NEXT(p, p_list))
106 			if (p->p_ucred->cr_uid == SCARG(uap, who) &&
107 			    p->p_nice < low)
108 				low = p->p_nice;
109 		break;
110 
111 	default:
112 		return (EINVAL);
113 	}
114 	if (low == NZERO + PRIO_MAX + 1)
115 		return (ESRCH);
116 	*retval = low - NZERO;
117 	return (0);
118 }
119 
120 /* ARGSUSED */
121 int
122 sys_setpriority(curp, v, retval)
123 	struct proc *curp;
124 	void *v;
125 	register_t *retval;
126 {
127 	register struct sys_setpriority_args /* {
128 		syscallarg(int) which;
129 		syscallarg(int) who;
130 		syscallarg(int) prio;
131 	} */ *uap = v;
132 	register struct proc *p;
133 	int found = 0, error = 0;
134 
135 	switch (SCARG(uap, which)) {
136 
137 	case PRIO_PROCESS:
138 		if (SCARG(uap, who) == 0)
139 			p = curp;
140 		else
141 			p = pfind(SCARG(uap, who));
142 		if (p == 0)
143 			break;
144 		error = donice(curp, p, SCARG(uap, prio));
145 		found++;
146 		break;
147 
148 	case PRIO_PGRP: {
149 		register struct pgrp *pg;
150 
151 		if (SCARG(uap, who) == 0)
152 			pg = curp->p_pgrp;
153 		else if ((pg = pgfind(SCARG(uap, who))) == NULL)
154 			break;
155 		for (p = pg->pg_members.lh_first; p != 0;
156 		    p = p->p_pglist.le_next) {
157 			error = donice(curp, p, SCARG(uap, prio));
158 			found++;
159 		}
160 		break;
161 	}
162 
163 	case PRIO_USER:
164 		if (SCARG(uap, who) == 0)
165 			SCARG(uap, who) = curp->p_ucred->cr_uid;
166 		for (p = LIST_FIRST(&allproc); p; p = LIST_NEXT(p, p_list))
167 			if (p->p_ucred->cr_uid == SCARG(uap, who)) {
168 				error = donice(curp, p, SCARG(uap, prio));
169 				found++;
170 			}
171 		break;
172 
173 	default:
174 		return (EINVAL);
175 	}
176 	if (found == 0)
177 		return (ESRCH);
178 	return (error);
179 }
180 
181 int
182 donice(curp, chgp, n)
183 	register struct proc *curp, *chgp;
184 	register int n;
185 {
186 	register struct pcred *pcred = curp->p_cred;
187 
188 	if (pcred->pc_ucred->cr_uid && pcred->p_ruid &&
189 	    pcred->pc_ucred->cr_uid != chgp->p_ucred->cr_uid &&
190 	    pcred->p_ruid != chgp->p_ucred->cr_uid)
191 		return (EPERM);
192 	if (n > PRIO_MAX)
193 		n = PRIO_MAX;
194 	if (n < PRIO_MIN)
195 		n = PRIO_MIN;
196 	n += NZERO;
197 	if (n < chgp->p_nice && suser(pcred->pc_ucred, &curp->p_acflag))
198 		return (EACCES);
199 	chgp->p_nice = n;
200 	(void)resetpriority(chgp);
201 	return (0);
202 }
203 
204 /* ARGSUSED */
205 int
206 sys_setrlimit(p, v, retval)
207 	struct proc *p;
208 	void *v;
209 	register_t *retval;
210 {
211 	register struct sys_setrlimit_args /* {
212 		syscallarg(u_int) which;
213 		syscallarg(struct rlimit *) rlp;
214 	} */ *uap = v;
215 	struct rlimit alim;
216 	int error;
217 
218 	error = copyin((caddr_t)SCARG(uap, rlp), (caddr_t)&alim,
219 		       sizeof (struct rlimit));
220 	if (error)
221 		return (error);
222 	return (dosetrlimit(p, SCARG(uap, which), &alim));
223 }
224 
225 int
226 dosetrlimit(p, which, limp)
227 	struct proc *p;
228 	u_int which;
229 	struct rlimit *limp;
230 {
231 	struct rlimit *alimp;
232 	extern unsigned maxdmap, maxsmap;
233 	rlim_t maxlim;
234 	int error;
235 
236 	if (which >= RLIM_NLIMITS)
237 		return (EINVAL);
238 
239 	if (limp->rlim_cur < 0 || limp->rlim_max < 0)
240 		return (EINVAL);
241 
242 	alimp = &p->p_rlimit[which];
243 	if (limp->rlim_cur > alimp->rlim_max ||
244 	    limp->rlim_max > alimp->rlim_max)
245 		if ((error = suser(p->p_ucred, &p->p_acflag)) != 0)
246 			return (error);
247 	if (p->p_limit->p_refcnt > 1 &&
248 	    (p->p_limit->p_lflags & PL_SHAREMOD) == 0) {
249 		p->p_limit->p_refcnt--;
250 		p->p_limit = limcopy(p->p_limit);
251 		alimp = &p->p_rlimit[which];
252 	}
253 
254 	switch (which) {
255 	case RLIMIT_DATA:
256 		maxlim = maxdmap;
257 		break;
258 	case RLIMIT_STACK:
259 		maxlim = maxsmap;
260 		break;
261 	case RLIMIT_NOFILE:
262 		maxlim = maxfiles;
263 		break;
264 	case RLIMIT_NPROC:
265 		maxlim = maxproc;
266 		break;
267 	default:
268 		maxlim = RLIM_INFINITY;
269 		break;
270 	}
271 
272 	if (limp->rlim_max > maxlim)
273 		limp->rlim_max = maxlim;
274 	if (limp->rlim_cur > limp->rlim_max)
275 		limp->rlim_cur = limp->rlim_max;
276 
277 	if (which == RLIMIT_STACK) {
278 		/*
279 		 * Stack is allocated to the max at exec time with only
280 		 * "rlim_cur" bytes accessible.  If stack limit is going
281 		 * up make more accessible, if going down make inaccessible.
282 		 */
283 		if (limp->rlim_cur != alimp->rlim_cur) {
284 			vaddr_t addr;
285 			vsize_t size;
286 			vm_prot_t prot;
287 
288 			if (limp->rlim_cur > alimp->rlim_cur) {
289 				prot = VM_PROT_ALL;
290 				size = limp->rlim_cur - alimp->rlim_cur;
291 #ifdef MACHINE_STACK_GROWS_UP
292 				addr = USRSTACK + alimp->rlim_cur;
293 #else
294 				addr = USRSTACK - limp->rlim_cur;
295 #endif
296 			} else {
297 				prot = VM_PROT_NONE;
298 				size = alimp->rlim_cur - limp->rlim_cur;
299 #ifdef MACHINE_STACK_GROWS_UP
300 				addr = USRSTACK + limp->rlim_cur;
301 #else
302 				addr = USRSTACK - alimp->rlim_cur;
303 #endif
304 			}
305 			addr = trunc_page(addr);
306 			size = round_page(size);
307 			(void) uvm_map_protect(&p->p_vmspace->vm_map,
308 					      addr, addr+size, prot, FALSE);
309 		}
310 	}
311 
312 	*alimp = *limp;
313 	return (0);
314 }
315 
316 /* ARGSUSED */
317 int
318 sys_getrlimit(p, v, retval)
319 	struct proc *p;
320 	void *v;
321 	register_t *retval;
322 {
323 	register struct sys_getrlimit_args /* {
324 		syscallarg(u_int) which;
325 		syscallarg(struct rlimit *) rlp;
326 	} */ *uap = v;
327 
328 	if (SCARG(uap, which) >= RLIM_NLIMITS)
329 		return (EINVAL);
330 	return (copyout((caddr_t)&p->p_rlimit[SCARG(uap, which)],
331 	    (caddr_t)SCARG(uap, rlp), sizeof (struct rlimit)));
332 }
333 
334 /*
335  * Transform the running time and tick information in proc p into user,
336  * system, and interrupt time usage.
337  */
338 void
339 calcru(p, up, sp, ip)
340 	register struct proc *p;
341 	register struct timeval *up;
342 	register struct timeval *sp;
343 	register struct timeval *ip;
344 {
345 	register u_quad_t u, st, ut, it, tot;
346 	register long sec, usec;
347 	register int s;
348 	struct timeval tv;
349 
350 	s = splstatclock();
351 	st = p->p_sticks;
352 	ut = p->p_uticks;
353 	it = p->p_iticks;
354 	splx(s);
355 
356 	tot = st + ut + it;
357 	if (tot == 0) {
358 		up->tv_sec = up->tv_usec = 0;
359 		sp->tv_sec = sp->tv_usec = 0;
360 		if (ip != NULL)
361 			ip->tv_sec = ip->tv_usec = 0;
362 		return;
363 	}
364 
365 	sec = p->p_rtime.tv_sec;
366 	usec = p->p_rtime.tv_usec;
367 	if (p == curproc) {
368 		/*
369 		 * Adjust for the current time slice.  This is actually fairly
370 		 * important since the error here is on the order of a time
371 		 * quantum, which is much greater than the sampling error.
372 		 */
373 		microtime(&tv);
374 		sec += tv.tv_sec - runtime.tv_sec;
375 		usec += tv.tv_usec - runtime.tv_usec;
376 	}
377 	u = (u_quad_t) sec * 1000000 + usec;
378 	st = (u * st) / tot;
379 	sp->tv_sec = st / 1000000;
380 	sp->tv_usec = st % 1000000;
381 	ut = (u * ut) / tot;
382 	up->tv_sec = ut / 1000000;
383 	up->tv_usec = ut % 1000000;
384 	if (ip != NULL) {
385 		it = (u * it) / tot;
386 		ip->tv_sec = it / 1000000;
387 		ip->tv_usec = it % 1000000;
388 	}
389 }
390 
391 /* ARGSUSED */
392 int
393 sys_getrusage(p, v, retval)
394 	register struct proc *p;
395 	void *v;
396 	register_t *retval;
397 {
398 	register struct sys_getrusage_args /* {
399 		syscallarg(int) who;
400 		syscallarg(struct rusage *) rusage;
401 	} */ *uap = v;
402 	register struct rusage *rup;
403 
404 	switch (SCARG(uap, who)) {
405 
406 	case RUSAGE_SELF:
407 		rup = &p->p_stats->p_ru;
408 		calcru(p, &rup->ru_utime, &rup->ru_stime, NULL);
409 		break;
410 
411 	case RUSAGE_CHILDREN:
412 		rup = &p->p_stats->p_cru;
413 		break;
414 
415 	default:
416 		return (EINVAL);
417 	}
418 	return (copyout((caddr_t)rup, (caddr_t)SCARG(uap, rusage),
419 	    sizeof (struct rusage)));
420 }
421 
422 void
423 ruadd(ru, ru2)
424 	register struct rusage *ru, *ru2;
425 {
426 	register long *ip, *ip2;
427 	register int i;
428 
429 	timeradd(&ru->ru_utime, &ru2->ru_utime, &ru->ru_utime);
430 	timeradd(&ru->ru_stime, &ru2->ru_stime, &ru->ru_stime);
431 	if (ru->ru_maxrss < ru2->ru_maxrss)
432 		ru->ru_maxrss = ru2->ru_maxrss;
433 	ip = &ru->ru_first; ip2 = &ru2->ru_first;
434 	for (i = &ru->ru_last - &ru->ru_first; i >= 0; i--)
435 		*ip++ += *ip2++;
436 }
437 
438 /*
439  * Make a copy of the plimit structure.
440  * We share these structures copy-on-write after fork,
441  * and copy when a limit is changed.
442  */
443 struct plimit *
444 limcopy(lim)
445 	struct plimit *lim;
446 {
447 	register struct plimit *newlim;
448 
449 	MALLOC(newlim, struct plimit *, sizeof(struct plimit),
450 	    M_SUBPROC, M_WAITOK);
451 	bcopy(lim->pl_rlimit, newlim->pl_rlimit,
452 	    sizeof(struct rlimit) * RLIM_NLIMITS);
453 	newlim->p_lflags = 0;
454 	newlim->p_refcnt = 1;
455 	return (newlim);
456 }
457 
458 void
459 limfree(lim)
460 	struct plimit *lim;
461 {
462 
463 	if (--lim->p_refcnt > 0)
464 		return;
465 	FREE(lim, M_SUBPROC);
466 }
467