xref: /netbsd-src/sys/kern/kern_resource.c (revision 81b108b45f75f89f1e3ffad9fb6f074e771c0935)
1 /*	$NetBSD: kern_resource.c,v 1.36 1996/07/11 00:09:29 jtc 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 void limfree __P((struct plimit *));
57 /*
58  * Resource controls and accounting.
59  */
60 
61 int
62 sys_getpriority(curp, v, retval)
63 	struct proc *curp;
64 	void *v;
65 	register_t *retval;
66 {
67 	register struct sys_getpriority_args /* {
68 		syscallarg(int) which;
69 		syscallarg(int) who;
70 	} */ *uap = v;
71 	register struct proc *p;
72 	register int low = PRIO_MAX + 1;
73 
74 	switch (SCARG(uap, which)) {
75 
76 	case PRIO_PROCESS:
77 		if (SCARG(uap, who) == 0)
78 			p = curp;
79 		else
80 			p = pfind(SCARG(uap, who));
81 		if (p == 0)
82 			break;
83 		low = p->p_nice;
84 		break;
85 
86 	case PRIO_PGRP: {
87 		register struct pgrp *pg;
88 
89 		if (SCARG(uap, who) == 0)
90 			pg = curp->p_pgrp;
91 		else if ((pg = pgfind(SCARG(uap, who))) == NULL)
92 			break;
93 		for (p = pg->pg_members.lh_first; p != 0; p = p->p_pglist.le_next) {
94 			if (p->p_nice < low)
95 				low = p->p_nice;
96 		}
97 		break;
98 	}
99 
100 	case PRIO_USER:
101 		if (SCARG(uap, who) == 0)
102 			SCARG(uap, who) = curp->p_ucred->cr_uid;
103 		for (p = allproc.lh_first; p != 0; p = p->p_list.le_next)
104 			if (p->p_ucred->cr_uid == SCARG(uap, who) &&
105 			    p->p_nice < low)
106 				low = p->p_nice;
107 		break;
108 
109 	default:
110 		return (EINVAL);
111 	}
112 	if (low == PRIO_MAX + 1)
113 		return (ESRCH);
114 	*retval = low;
115 	return (0);
116 }
117 
118 /* ARGSUSED */
119 int
120 sys_setpriority(curp, v, retval)
121 	struct proc *curp;
122 	void *v;
123 	register_t *retval;
124 {
125 	register struct sys_setpriority_args /* {
126 		syscallarg(int) which;
127 		syscallarg(int) who;
128 		syscallarg(int) prio;
129 	} */ *uap = v;
130 	register struct proc *p;
131 	int found = 0, error = 0;
132 
133 	switch (SCARG(uap, which)) {
134 
135 	case PRIO_PROCESS:
136 		if (SCARG(uap, who) == 0)
137 			p = curp;
138 		else
139 			p = pfind(SCARG(uap, who));
140 		if (p == 0)
141 			break;
142 		error = donice(curp, p, SCARG(uap, prio));
143 		found++;
144 		break;
145 
146 	case PRIO_PGRP: {
147 		register struct pgrp *pg;
148 
149 		if (SCARG(uap, who) == 0)
150 			pg = curp->p_pgrp;
151 		else if ((pg = pgfind(SCARG(uap, who))) == NULL)
152 			break;
153 		for (p = pg->pg_members.lh_first; p != 0;
154 		    p = p->p_pglist.le_next) {
155 			error = donice(curp, p, SCARG(uap, prio));
156 			found++;
157 		}
158 		break;
159 	}
160 
161 	case PRIO_USER:
162 		if (SCARG(uap, who) == 0)
163 			SCARG(uap, who) = curp->p_ucred->cr_uid;
164 		for (p = allproc.lh_first; p != 0; p = p->p_list.le_next)
165 			if (p->p_ucred->cr_uid == SCARG(uap, who)) {
166 				error = donice(curp, p, SCARG(uap, prio));
167 				found++;
168 			}
169 		break;
170 
171 	default:
172 		return (EINVAL);
173 	}
174 	if (found == 0)
175 		return (ESRCH);
176 	return (error);
177 }
178 
179 int
180 donice(curp, chgp, n)
181 	register struct proc *curp, *chgp;
182 	register int n;
183 {
184 	register struct pcred *pcred = curp->p_cred;
185 
186 	if (pcred->pc_ucred->cr_uid && pcred->p_ruid &&
187 	    pcred->pc_ucred->cr_uid != chgp->p_ucred->cr_uid &&
188 	    pcred->p_ruid != chgp->p_ucred->cr_uid)
189 		return (EPERM);
190 	if (n > PRIO_MAX)
191 		n = PRIO_MAX;
192 	if (n < PRIO_MIN)
193 		n = PRIO_MIN;
194 	if (n < chgp->p_nice && suser(pcred->pc_ucred, &curp->p_acflag))
195 		return (EACCES);
196 	chgp->p_nice = n;
197 	(void)resetpriority(chgp);
198 	return (0);
199 }
200 
201 /* ARGSUSED */
202 int
203 sys_setrlimit(p, v, retval)
204 	struct proc *p;
205 	void *v;
206 	register_t *retval;
207 {
208 	register struct sys_setrlimit_args /* {
209 		syscallarg(u_int) which;
210 		syscallarg(struct rlimit *) rlp;
211 	} */ *uap = v;
212 	struct rlimit alim;
213 	int error;
214 
215 	error = copyin((caddr_t)SCARG(uap, rlp), (caddr_t)&alim,
216 		       sizeof (struct rlimit));
217 	if (error)
218 		return (error);
219 	return (dosetrlimit(p, SCARG(uap, which), &alim));
220 }
221 
222 int
223 dosetrlimit(p, which, limp)
224 	struct proc *p;
225 	u_int which;
226 	struct rlimit *limp;
227 {
228 	register struct rlimit *alimp;
229 	extern unsigned maxdmap, maxsmap;
230 	int error;
231 
232 	if (which >= RLIM_NLIMITS)
233 		return (EINVAL);
234 	alimp = &p->p_rlimit[which];
235 	if (limp->rlim_cur > alimp->rlim_max ||
236 	    limp->rlim_max > alimp->rlim_max)
237 		if ((error = suser(p->p_ucred, &p->p_acflag)) != 0)
238 			return (error);
239 	if (limp->rlim_cur > limp->rlim_max)
240 		limp->rlim_cur = limp->rlim_max;
241 	if (p->p_limit->p_refcnt > 1 &&
242 	    (p->p_limit->p_lflags & PL_SHAREMOD) == 0) {
243 		p->p_limit->p_refcnt--;
244 		p->p_limit = limcopy(p->p_limit);
245 		alimp = &p->p_rlimit[which];
246 	}
247 
248 	switch (which) {
249 
250 	case RLIMIT_DATA:
251 		if (limp->rlim_cur > maxdmap)
252 			limp->rlim_cur = maxdmap;
253 		if (limp->rlim_max > maxdmap)
254 			limp->rlim_max = maxdmap;
255 		break;
256 
257 	case RLIMIT_STACK:
258 		if (limp->rlim_cur > maxsmap)
259 			limp->rlim_cur = maxsmap;
260 		if (limp->rlim_max > maxsmap)
261 			limp->rlim_max = maxsmap;
262 		/*
263 		 * Stack is allocated to the max at exec time with only
264 		 * "rlim_cur" bytes accessible.  If stack limit is going
265 		 * up make more accessible, if going down make inaccessible.
266 		 */
267 		if (limp->rlim_cur != alimp->rlim_cur) {
268 			vm_offset_t addr;
269 			vm_size_t size;
270 			vm_prot_t prot;
271 
272 			if (limp->rlim_cur > alimp->rlim_cur) {
273 				prot = VM_PROT_ALL;
274 				size = limp->rlim_cur - alimp->rlim_cur;
275 				addr = USRSTACK - limp->rlim_cur;
276 			} else {
277 				prot = VM_PROT_NONE;
278 				size = alimp->rlim_cur - limp->rlim_cur;
279 				addr = USRSTACK - alimp->rlim_cur;
280 			}
281 			addr = trunc_page(addr);
282 			size = round_page(size);
283 			(void) vm_map_protect(&p->p_vmspace->vm_map,
284 					      addr, addr+size, prot, FALSE);
285 		}
286 		break;
287 
288 	case RLIMIT_NOFILE:
289 		if (limp->rlim_cur > maxfiles)
290 			limp->rlim_cur = maxfiles;
291 		if (limp->rlim_max > maxfiles)
292 			limp->rlim_max = maxfiles;
293 		break;
294 
295 	case RLIMIT_NPROC:
296 		if (limp->rlim_cur > maxproc)
297 			limp->rlim_cur = maxproc;
298 		if (limp->rlim_max > maxproc)
299 			limp->rlim_max = maxproc;
300 		break;
301 	}
302 	*alimp = *limp;
303 	return (0);
304 }
305 
306 /* ARGSUSED */
307 int
308 sys_getrlimit(p, v, retval)
309 	struct proc *p;
310 	void *v;
311 	register_t *retval;
312 {
313 	register struct sys_getrlimit_args /* {
314 		syscallarg(u_int) which;
315 		syscallarg(struct rlimit *) rlp;
316 	} */ *uap = v;
317 
318 	if (SCARG(uap, which) >= RLIM_NLIMITS)
319 		return (EINVAL);
320 	return (copyout((caddr_t)&p->p_rlimit[SCARG(uap, which)],
321 	    (caddr_t)SCARG(uap, rlp), sizeof (struct rlimit)));
322 }
323 
324 /*
325  * Transform the running time and tick information in proc p into user,
326  * system, and interrupt time usage.
327  */
328 void
329 calcru(p, up, sp, ip)
330 	register struct proc *p;
331 	register struct timeval *up;
332 	register struct timeval *sp;
333 	register struct timeval *ip;
334 {
335 	register u_quad_t u, st, ut, it, tot;
336 	register long sec, usec;
337 	register int s;
338 	struct timeval tv;
339 
340 	s = splstatclock();
341 	st = p->p_sticks;
342 	ut = p->p_uticks;
343 	it = p->p_iticks;
344 	splx(s);
345 
346 	tot = st + ut + it;
347 	if (tot == 0) {
348 		up->tv_sec = up->tv_usec = 0;
349 		sp->tv_sec = sp->tv_usec = 0;
350 		if (ip != NULL)
351 			ip->tv_sec = ip->tv_usec = 0;
352 		return;
353 	}
354 
355 	sec = p->p_rtime.tv_sec;
356 	usec = p->p_rtime.tv_usec;
357 	if (p == curproc) {
358 		/*
359 		 * Adjust for the current time slice.  This is actually fairly
360 		 * important since the error here is on the order of a time
361 		 * quantum, which is much greater than the sampling error.
362 		 */
363 		microtime(&tv);
364 		sec += tv.tv_sec - runtime.tv_sec;
365 		usec += tv.tv_usec - runtime.tv_usec;
366 	}
367 	u = (u_quad_t) sec * 1000000 + usec;
368 	st = (u * st) / tot;
369 	sp->tv_sec = st / 1000000;
370 	sp->tv_usec = st % 1000000;
371 	ut = (u * ut) / tot;
372 	up->tv_sec = ut / 1000000;
373 	up->tv_usec = ut % 1000000;
374 	if (ip != NULL) {
375 		it = (u * it) / tot;
376 		ip->tv_sec = it / 1000000;
377 		ip->tv_usec = it % 1000000;
378 	}
379 }
380 
381 /* ARGSUSED */
382 int
383 sys_getrusage(p, v, retval)
384 	register struct proc *p;
385 	void *v;
386 	register_t *retval;
387 {
388 	register struct sys_getrusage_args /* {
389 		syscallarg(int) who;
390 		syscallarg(struct rusage *) rusage;
391 	} */ *uap = v;
392 	register struct rusage *rup;
393 
394 	switch (SCARG(uap, who)) {
395 
396 	case RUSAGE_SELF:
397 		rup = &p->p_stats->p_ru;
398 		calcru(p, &rup->ru_utime, &rup->ru_stime, NULL);
399 		break;
400 
401 	case RUSAGE_CHILDREN:
402 		rup = &p->p_stats->p_cru;
403 		break;
404 
405 	default:
406 		return (EINVAL);
407 	}
408 	return (copyout((caddr_t)rup, (caddr_t)SCARG(uap, rusage),
409 	    sizeof (struct rusage)));
410 }
411 
412 void
413 ruadd(ru, ru2)
414 	register struct rusage *ru, *ru2;
415 {
416 	register long *ip, *ip2;
417 	register int i;
418 
419 	timeradd(&ru->ru_utime, &ru2->ru_utime, &ru->ru_utime);
420 	timeradd(&ru->ru_stime, &ru2->ru_stime, &ru->ru_stime);
421 	if (ru->ru_maxrss < ru2->ru_maxrss)
422 		ru->ru_maxrss = ru2->ru_maxrss;
423 	ip = &ru->ru_first; ip2 = &ru2->ru_first;
424 	for (i = &ru->ru_last - &ru->ru_first; i >= 0; i--)
425 		*ip++ += *ip2++;
426 }
427 
428 /*
429  * Make a copy of the plimit structure.
430  * We share these structures copy-on-write after fork,
431  * and copy when a limit is changed.
432  */
433 struct plimit *
434 limcopy(lim)
435 	struct plimit *lim;
436 {
437 	register struct plimit *newlim;
438 
439 	MALLOC(newlim, struct plimit *, sizeof(struct plimit),
440 	    M_SUBPROC, M_WAITOK);
441 	bcopy(lim->pl_rlimit, newlim->pl_rlimit,
442 	    sizeof(struct rlimit) * RLIM_NLIMITS);
443 	newlim->p_lflags = 0;
444 	newlim->p_refcnt = 1;
445 	return (newlim);
446 }
447 
448 void
449 limfree(lim)
450 	struct plimit *lim;
451 {
452 
453 	if (--lim->p_refcnt > 0)
454 		return;
455 	FREE(lim, M_SUBPROC);
456 }
457