xref: /netbsd-src/sys/kern/kern_resource.c (revision 481fca6e59249d8ffcf24fef7cfbe7b131bfb080)
1 /*	$NetBSD: kern_resource.c,v 1.58 2000/06/27 17:41:25 mrg 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  * 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 	struct sys_getpriority_args /* {
68 		syscallarg(int) which;
69 		syscallarg(int) who;
70 	} */ *uap = v;
71 	struct proc *p;
72 	int low = NZERO + 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 		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;
94 		     p = p->p_pglist.le_next) {
95 			if (p->p_nice < low)
96 				low = p->p_nice;
97 		}
98 		break;
99 	}
100 
101 	case PRIO_USER:
102 		if (SCARG(uap, who) == 0)
103 			SCARG(uap, who) = curp->p_ucred->cr_uid;
104 		proclist_lock_read();
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 		proclist_unlock_read();
110 		break;
111 
112 	default:
113 		return (EINVAL);
114 	}
115 	if (low == NZERO + PRIO_MAX + 1)
116 		return (ESRCH);
117 	*retval = low - NZERO;
118 	return (0);
119 }
120 
121 /* ARGSUSED */
122 int
123 sys_setpriority(curp, v, retval)
124 	struct proc *curp;
125 	void *v;
126 	register_t *retval;
127 {
128 	struct sys_setpriority_args /* {
129 		syscallarg(int) which;
130 		syscallarg(int) who;
131 		syscallarg(int) prio;
132 	} */ *uap = v;
133 	struct proc *p;
134 	int found = 0, error = 0;
135 
136 	switch (SCARG(uap, which)) {
137 
138 	case PRIO_PROCESS:
139 		if (SCARG(uap, who) == 0)
140 			p = curp;
141 		else
142 			p = pfind(SCARG(uap, who));
143 		if (p == 0)
144 			break;
145 		error = donice(curp, p, SCARG(uap, prio));
146 		found++;
147 		break;
148 
149 	case PRIO_PGRP: {
150 		struct pgrp *pg;
151 
152 		if (SCARG(uap, who) == 0)
153 			pg = curp->p_pgrp;
154 		else if ((pg = pgfind(SCARG(uap, who))) == NULL)
155 			break;
156 		for (p = pg->pg_members.lh_first; p != 0;
157 		    p = p->p_pglist.le_next) {
158 			error = donice(curp, p, SCARG(uap, prio));
159 			found++;
160 		}
161 		break;
162 	}
163 
164 	case PRIO_USER:
165 		if (SCARG(uap, who) == 0)
166 			SCARG(uap, who) = curp->p_ucred->cr_uid;
167 		proclist_lock_read();
168 		for (p = allproc.lh_first; p != 0; p = p->p_list.le_next)
169 			if (p->p_ucred->cr_uid == SCARG(uap, who)) {
170 				error = donice(curp, p, SCARG(uap, prio));
171 				found++;
172 			}
173 		proclist_unlock_read();
174 		break;
175 
176 	default:
177 		return (EINVAL);
178 	}
179 	if (found == 0)
180 		return (ESRCH);
181 	return (error);
182 }
183 
184 int
185 donice(curp, chgp, n)
186 	struct proc *curp, *chgp;
187 	int n;
188 {
189 	struct pcred *pcred = curp->p_cred;
190 
191 	if (pcred->pc_ucred->cr_uid && pcred->p_ruid &&
192 	    pcred->pc_ucred->cr_uid != chgp->p_ucred->cr_uid &&
193 	    pcred->p_ruid != chgp->p_ucred->cr_uid)
194 		return (EPERM);
195 	if (n > PRIO_MAX)
196 		n = PRIO_MAX;
197 	if (n < PRIO_MIN)
198 		n = PRIO_MIN;
199 	n += NZERO;
200 	if (n < chgp->p_nice && suser(pcred->pc_ucred, &curp->p_acflag))
201 		return (EACCES);
202 	chgp->p_nice = n;
203 	(void)resetpriority(chgp);
204 	return (0);
205 }
206 
207 /* ARGSUSED */
208 int
209 sys_setrlimit(p, v, retval)
210 	struct proc *p;
211 	void *v;
212 	register_t *retval;
213 {
214 	struct sys_setrlimit_args /* {
215 		syscallarg(int) which;
216 		syscallarg(const struct rlimit *) rlp;
217 	} */ *uap = v;
218 	int which = SCARG(uap, which);
219 	struct rlimit alim;
220 	int error;
221 
222 	error = copyin(SCARG(uap, rlp), &alim, sizeof(struct rlimit));
223 	if (error)
224 		return (error);
225 	return (dosetrlimit(p, p->p_cred, which, &alim));
226 }
227 
228 int
229 dosetrlimit(p, cred, which, limp)
230 	struct proc *p;
231 	struct  pcred *cred;
232 	int which;
233 	struct rlimit *limp;
234 {
235 	struct rlimit *alimp;
236 	extern unsigned maxdmap, maxsmap;
237 	struct plimit *newplim;
238 	int error;
239 
240 	if ((u_int)which >= RLIM_NLIMITS)
241 		return (EINVAL);
242 
243 	if (limp->rlim_cur < 0 || limp->rlim_max < 0)
244 		return (EINVAL);
245 
246 	alimp = &p->p_rlimit[which];
247 	/* if we don't change the value, no need to limcopy() */
248 	if (limp->rlim_cur == alimp->rlim_cur &&
249 	    limp->rlim_max == alimp->rlim_max)
250 		return 0;
251 
252 	if (limp->rlim_cur > alimp->rlim_max ||
253 	    limp->rlim_max > alimp->rlim_max)
254 		if ((error = suser(cred->pc_ucred, &p->p_acflag)) != 0)
255 			return (error);
256 	if (limp->rlim_cur > limp->rlim_max)
257 		limp->rlim_cur = limp->rlim_max;
258 	if (p->p_limit->p_refcnt > 1 &&
259 	    (p->p_limit->p_lflags & PL_SHAREMOD) == 0) {
260 		newplim = limcopy(p->p_limit);
261 		limfree(p->p_limit);
262 		p->p_limit = newplim;
263 		alimp = &p->p_rlimit[which];
264 	}
265 
266 	switch (which) {
267 
268 	case RLIMIT_DATA:
269 		if (limp->rlim_cur > maxdmap)
270 			limp->rlim_cur = maxdmap;
271 		if (limp->rlim_max > maxdmap)
272 			limp->rlim_max = maxdmap;
273 		break;
274 
275 	case RLIMIT_STACK:
276 		if (limp->rlim_cur > maxsmap)
277 			limp->rlim_cur = maxsmap;
278 		if (limp->rlim_max > maxsmap)
279 			limp->rlim_max = maxsmap;
280 
281 		/*
282 		 * Stack is allocated to the max at exec time with
283 		 * only "rlim_cur" bytes accessible (In other words,
284 		 * allocates stack dividing two contiguous regions at
285 		 * "rlim_cur" bytes boundary).
286 		 *
287 		 * Since allocation is done in terms of page, roundup
288 		 * "rlim_cur" (otherwise, contiguous regions
289 		 * overlap).  If stack limit is going up make more
290 		 * accessible, if going down make inaccessible.
291 		 */
292 		limp->rlim_cur = round_page(limp->rlim_cur);
293 		if (limp->rlim_cur != alimp->rlim_cur) {
294 			vaddr_t addr;
295 			vsize_t size;
296 			vm_prot_t prot;
297 
298 			if (limp->rlim_cur > alimp->rlim_cur) {
299 				prot = VM_PROT_ALL;
300 				size = limp->rlim_cur - alimp->rlim_cur;
301 				addr = USRSTACK - limp->rlim_cur;
302 			} else {
303 				prot = VM_PROT_NONE;
304 				size = alimp->rlim_cur - limp->rlim_cur;
305 				addr = USRSTACK - alimp->rlim_cur;
306 			}
307 			(void) uvm_map_protect(&p->p_vmspace->vm_map,
308 					      addr, addr+size, prot, FALSE);
309 		}
310 		break;
311 
312 	case RLIMIT_NOFILE:
313 		if (limp->rlim_cur > maxfiles)
314 			limp->rlim_cur = maxfiles;
315 		if (limp->rlim_max > maxfiles)
316 			limp->rlim_max = maxfiles;
317 		break;
318 
319 	case RLIMIT_NPROC:
320 		if (limp->rlim_cur > maxproc)
321 			limp->rlim_cur = maxproc;
322 		if (limp->rlim_max > maxproc)
323 			limp->rlim_max = maxproc;
324 		break;
325 	}
326 	*alimp = *limp;
327 	return (0);
328 }
329 
330 /* ARGSUSED */
331 int
332 sys_getrlimit(p, v, retval)
333 	struct proc *p;
334 	void *v;
335 	register_t *retval;
336 {
337 	struct sys_getrlimit_args /* {
338 		syscallarg(int) which;
339 		syscallarg(struct rlimit *) rlp;
340 	} */ *uap = v;
341 	int which = SCARG(uap, which);
342 
343 	if ((u_int)which >= RLIM_NLIMITS)
344 		return (EINVAL);
345 	return (copyout(&p->p_rlimit[which], SCARG(uap, rlp),
346 	    sizeof(struct rlimit)));
347 }
348 
349 /*
350  * Transform the running time and tick information in proc p into user,
351  * system, and interrupt time usage.
352  */
353 void
354 calcru(p, up, sp, ip)
355 	struct proc *p;
356 	struct timeval *up;
357 	struct timeval *sp;
358 	struct timeval *ip;
359 {
360 	u_quad_t u, st, ut, it, tot;
361 	long sec, usec;
362 	int s;
363 	struct timeval tv;
364 
365 	s = splstatclock();
366 	st = p->p_sticks;
367 	ut = p->p_uticks;
368 	it = p->p_iticks;
369 	splx(s);
370 
371 	tot = st + ut + it;
372 	if (tot == 0) {
373 		up->tv_sec = up->tv_usec = 0;
374 		sp->tv_sec = sp->tv_usec = 0;
375 		if (ip != NULL)
376 			ip->tv_sec = ip->tv_usec = 0;
377 		return;
378 	}
379 
380 	sec = p->p_rtime.tv_sec;
381 	usec = p->p_rtime.tv_usec;
382 	if (p->p_stat == SONPROC) {
383 		struct schedstate_percpu *spc;
384 
385 		KDASSERT(p->p_cpu != NULL);
386 		spc = &p->p_cpu->ci_schedstate;
387 
388 		/*
389 		 * Adjust for the current time slice.  This is actually fairly
390 		 * important since the error here is on the order of a time
391 		 * quantum, which is much greater than the sampling error.
392 		 */
393 		microtime(&tv);
394 		sec += tv.tv_sec - spc->spc_runtime.tv_sec;
395 		usec += tv.tv_usec - spc->spc_runtime.tv_usec;
396 	}
397 	u = (u_quad_t) sec * 1000000 + usec;
398 	st = (u * st) / tot;
399 	sp->tv_sec = st / 1000000;
400 	sp->tv_usec = st % 1000000;
401 	ut = (u * ut) / tot;
402 	up->tv_sec = ut / 1000000;
403 	up->tv_usec = ut % 1000000;
404 	if (ip != NULL) {
405 		it = (u * it) / tot;
406 		ip->tv_sec = it / 1000000;
407 		ip->tv_usec = it % 1000000;
408 	}
409 }
410 
411 /* ARGSUSED */
412 int
413 sys_getrusage(p, v, retval)
414 	struct proc *p;
415 	void *v;
416 	register_t *retval;
417 {
418 	struct sys_getrusage_args /* {
419 		syscallarg(int) who;
420 		syscallarg(struct rusage *) rusage;
421 	} */ *uap = v;
422 	struct rusage *rup;
423 
424 	switch (SCARG(uap, who)) {
425 
426 	case RUSAGE_SELF:
427 		rup = &p->p_stats->p_ru;
428 		calcru(p, &rup->ru_utime, &rup->ru_stime, NULL);
429 		break;
430 
431 	case RUSAGE_CHILDREN:
432 		rup = &p->p_stats->p_cru;
433 		break;
434 
435 	default:
436 		return (EINVAL);
437 	}
438 	return (copyout(rup, SCARG(uap, rusage), sizeof(struct rusage)));
439 }
440 
441 void
442 ruadd(ru, ru2)
443 	struct rusage *ru, *ru2;
444 {
445 	long *ip, *ip2;
446 	int i;
447 
448 	timeradd(&ru->ru_utime, &ru2->ru_utime, &ru->ru_utime);
449 	timeradd(&ru->ru_stime, &ru2->ru_stime, &ru->ru_stime);
450 	if (ru->ru_maxrss < ru2->ru_maxrss)
451 		ru->ru_maxrss = ru2->ru_maxrss;
452 	ip = &ru->ru_first; ip2 = &ru2->ru_first;
453 	for (i = &ru->ru_last - &ru->ru_first; i >= 0; i--)
454 		*ip++ += *ip2++;
455 }
456 
457 /*
458  * Make a copy of the plimit structure.
459  * We share these structures copy-on-write after fork,
460  * and copy when a limit is changed.
461  */
462 struct plimit *
463 limcopy(lim)
464 	struct plimit *lim;
465 {
466 	struct plimit *newlim;
467 
468 	newlim = pool_get(&plimit_pool, PR_WAITOK);
469 	memcpy(newlim->pl_rlimit, lim->pl_rlimit,
470 	    sizeof(struct rlimit) * RLIM_NLIMITS);
471 	if (lim->pl_corename == defcorename) {
472 		newlim->pl_corename = defcorename;
473 	} else {
474 		newlim->pl_corename = malloc(strlen(lim->pl_corename)+1,
475 		    M_TEMP, M_WAITOK);
476 		strcpy(newlim->pl_corename, lim->pl_corename);
477 	}
478 	newlim->p_lflags = 0;
479 	newlim->p_refcnt = 1;
480 	return (newlim);
481 }
482 
483 void
484 limfree(lim)
485 	struct plimit *lim;
486 {
487 
488 	if (--lim->p_refcnt > 0)
489 		return;
490 #ifdef DIAGNOSTIC
491 	if (lim->p_refcnt < 0)
492 		panic("limfree");
493 #endif
494 	if (lim->pl_corename != defcorename)
495 		free(lim->pl_corename, M_TEMP);
496 	pool_put(&plimit_pool, lim);
497 }
498