xref: /openbsd-src/sys/kern/kern_resource.c (revision df930be708d50e9715f173caa26ffe1b7599b157)
1 /*	$NetBSD: kern_resource.c,v 1.31 1995/10/07 06:28:23 mycroft 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	8.5 (Berkeley) 1/21/94
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/proc.h>
50 
51 #include <sys/mount.h>
52 #include <sys/syscallargs.h>
53 
54 #include <vm/vm.h>
55 
56 int	donice __P((struct proc *curp, struct proc *chgp, int n));
57 int	dosetrlimit __P((struct proc *p, u_int which, struct rlimit *limp));
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 = 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 = allproc.lh_first; p != 0; p = p->p_list.le_next)
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 == PRIO_MAX + 1)
115 		return (ESRCH);
116 	*retval = low;
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 = allproc.lh_first; p != 0; p = p->p_list.le_next)
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 	if (n < chgp->p_nice && suser(pcred->pc_ucred, &curp->p_acflag))
197 		return (EACCES);
198 	chgp->p_nice = n;
199 	(void)resetpriority(chgp);
200 	return (0);
201 }
202 
203 /* ARGSUSED */
204 int
205 sys_setrlimit(p, v, retval)
206 	struct proc *p;
207 	void *v;
208 	register_t *retval;
209 {
210 	register struct sys_setrlimit_args /* {
211 		syscallarg(u_int) which;
212 		syscallarg(struct rlimit *) rlp;
213 	} */ *uap = v;
214 	struct rlimit alim;
215 	int error;
216 
217 	if (error = copyin((caddr_t)SCARG(uap, rlp), (caddr_t)&alim,
218 	    sizeof (struct rlimit)))
219 		return (error);
220 	return (dosetrlimit(p, SCARG(uap, which), &alim));
221 }
222 
223 int
224 dosetrlimit(p, which, limp)
225 	struct proc *p;
226 	u_int which;
227 	struct rlimit *limp;
228 {
229 	register struct rlimit *alimp;
230 	extern unsigned maxdmap, maxsmap;
231 	int error;
232 
233 	if (which >= RLIM_NLIMITS)
234 		return (EINVAL);
235 	alimp = &p->p_rlimit[which];
236 	if (limp->rlim_cur > alimp->rlim_max ||
237 	    limp->rlim_max > alimp->rlim_max)
238 		if (error = suser(p->p_ucred, &p->p_acflag))
239 			return (error);
240 	if (limp->rlim_cur > limp->rlim_max)
241 		limp->rlim_cur = limp->rlim_max;
242 	if (p->p_limit->p_refcnt > 1 &&
243 	    (p->p_limit->p_lflags & PL_SHAREMOD) == 0) {
244 		p->p_limit->p_refcnt--;
245 		p->p_limit = limcopy(p->p_limit);
246 		alimp = &p->p_rlimit[which];
247 	}
248 
249 	switch (which) {
250 
251 	case RLIMIT_DATA:
252 		if (limp->rlim_cur > maxdmap)
253 			limp->rlim_cur = maxdmap;
254 		if (limp->rlim_max > maxdmap)
255 			limp->rlim_max = maxdmap;
256 		break;
257 
258 	case RLIMIT_STACK:
259 		if (limp->rlim_cur > maxsmap)
260 			limp->rlim_cur = maxsmap;
261 		if (limp->rlim_max > maxsmap)
262 			limp->rlim_max = maxsmap;
263 		/*
264 		 * Stack is allocated to the max at exec time with only
265 		 * "rlim_cur" bytes accessible.  If stack limit is going
266 		 * up make more accessible, if going down make inaccessible.
267 		 */
268 		if (limp->rlim_cur != alimp->rlim_cur) {
269 			vm_offset_t addr;
270 			vm_size_t size;
271 			vm_prot_t prot;
272 
273 			if (limp->rlim_cur > alimp->rlim_cur) {
274 				prot = VM_PROT_ALL;
275 				size = limp->rlim_cur - alimp->rlim_cur;
276 				addr = USRSTACK - limp->rlim_cur;
277 			} else {
278 				prot = VM_PROT_NONE;
279 				size = alimp->rlim_cur - limp->rlim_cur;
280 				addr = USRSTACK - alimp->rlim_cur;
281 			}
282 			addr = trunc_page(addr);
283 			size = round_page(size);
284 			(void) vm_map_protect(&p->p_vmspace->vm_map,
285 					      addr, addr+size, prot, FALSE);
286 		}
287 		break;
288 
289 	case RLIMIT_NOFILE:
290 		if (limp->rlim_cur > maxfiles)
291 			limp->rlim_cur = maxfiles;
292 		if (limp->rlim_max > maxfiles)
293 			limp->rlim_max = maxfiles;
294 		break;
295 
296 	case RLIMIT_NPROC:
297 		if (limp->rlim_cur > maxproc)
298 			limp->rlim_cur = maxproc;
299 		if (limp->rlim_max > maxproc)
300 			limp->rlim_max = maxproc;
301 		break;
302 	}
303 	*alimp = *limp;
304 	return (0);
305 }
306 
307 /* ARGSUSED */
308 int
309 sys_getrlimit(p, v, retval)
310 	struct proc *p;
311 	void *v;
312 	register_t *retval;
313 {
314 	register struct sys_getrlimit_args /* {
315 		syscallarg(u_int) which;
316 		syscallarg(struct rlimit *) rlp;
317 	} */ *uap = v;
318 
319 	if (SCARG(uap, which) >= RLIM_NLIMITS)
320 		return (EINVAL);
321 	return (copyout((caddr_t)&p->p_rlimit[SCARG(uap, which)],
322 	    (caddr_t)SCARG(uap, rlp), sizeof (struct rlimit)));
323 }
324 
325 /*
326  * Transform the running time and tick information in proc p into user,
327  * system, and interrupt time usage.
328  */
329 void
330 calcru(p, up, sp, ip)
331 	register struct proc *p;
332 	register struct timeval *up;
333 	register struct timeval *sp;
334 	register struct timeval *ip;
335 {
336 	register u_quad_t u, st, ut, it, tot;
337 	register u_long sec, usec;
338 	register int s;
339 	struct timeval tv;
340 
341 	s = splstatclock();
342 	st = p->p_sticks;
343 	ut = p->p_uticks;
344 	it = p->p_iticks;
345 	splx(s);
346 
347 	tot = st + ut + it;
348 	if (tot == 0) {
349 		up->tv_sec = up->tv_usec = 0;
350 		sp->tv_sec = sp->tv_usec = 0;
351 		if (ip != NULL)
352 			ip->tv_sec = ip->tv_usec = 0;
353 		return;
354 	}
355 
356 	sec = p->p_rtime.tv_sec;
357 	usec = p->p_rtime.tv_usec;
358 	if (p == curproc) {
359 		/*
360 		 * Adjust for the current time slice.  This is actually fairly
361 		 * important since the error here is on the order of a time
362 		 * quantum, which is much greater than the sampling error.
363 		 */
364 		microtime(&tv);
365 		sec += tv.tv_sec - runtime.tv_sec;
366 		usec += tv.tv_usec - runtime.tv_usec;
367 	}
368 	u = sec * 1000000 + usec;
369 	st = (u * st) / tot;
370 	sp->tv_sec = st / 1000000;
371 	sp->tv_usec = st % 1000000;
372 	ut = (u * ut) / tot;
373 	up->tv_sec = ut / 1000000;
374 	up->tv_usec = ut % 1000000;
375 	if (ip != NULL) {
376 		it = (u * it) / tot;
377 		ip->tv_sec = it / 1000000;
378 		ip->tv_usec = it % 1000000;
379 	}
380 }
381 
382 /* ARGSUSED */
383 int
384 sys_getrusage(p, v, retval)
385 	register struct proc *p;
386 	void *v;
387 	register_t *retval;
388 {
389 	register struct sys_getrusage_args /* {
390 		syscallarg(int) who;
391 		syscallarg(struct rusage *) rusage;
392 	} */ *uap = v;
393 	register struct rusage *rup;
394 
395 	switch (SCARG(uap, who)) {
396 
397 	case RUSAGE_SELF:
398 		rup = &p->p_stats->p_ru;
399 		calcru(p, &rup->ru_utime, &rup->ru_stime, NULL);
400 		break;
401 
402 	case RUSAGE_CHILDREN:
403 		rup = &p->p_stats->p_cru;
404 		break;
405 
406 	default:
407 		return (EINVAL);
408 	}
409 	return (copyout((caddr_t)rup, (caddr_t)SCARG(uap, rusage),
410 	    sizeof (struct rusage)));
411 }
412 
413 void
414 ruadd(ru, ru2)
415 	register struct rusage *ru, *ru2;
416 {
417 	register long *ip, *ip2;
418 	register int i;
419 
420 	timeradd(&ru->ru_utime, &ru2->ru_utime, &ru->ru_utime);
421 	timeradd(&ru->ru_stime, &ru2->ru_stime, &ru->ru_stime);
422 	if (ru->ru_maxrss < ru2->ru_maxrss)
423 		ru->ru_maxrss = ru2->ru_maxrss;
424 	ip = &ru->ru_first; ip2 = &ru2->ru_first;
425 	for (i = &ru->ru_last - &ru->ru_first; i >= 0; i--)
426 		*ip++ += *ip2++;
427 }
428 
429 /*
430  * Make a copy of the plimit structure.
431  * We share these structures copy-on-write after fork,
432  * and copy when a limit is changed.
433  */
434 struct plimit *
435 limcopy(lim)
436 	struct plimit *lim;
437 {
438 	register struct plimit *copy;
439 
440 	MALLOC(copy, struct plimit *, sizeof(struct plimit),
441 	    M_SUBPROC, M_WAITOK);
442 	bcopy(lim->pl_rlimit, copy->pl_rlimit,
443 	    sizeof(struct rlimit) * RLIM_NLIMITS);
444 	copy->p_lflags = 0;
445 	copy->p_refcnt = 1;
446 	return (copy);
447 }
448