xref: /netbsd-src/sys/kern/kern_resource.c (revision 5aefcfdc06931dd97e76246d2fe0302f7b3fe094)
1 /*	$NetBSD: kern_resource.c,v 1.59 2000/08/20 21:50:11 thorpej 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 	int s;
191 
192 	if (pcred->pc_ucred->cr_uid && pcred->p_ruid &&
193 	    pcred->pc_ucred->cr_uid != chgp->p_ucred->cr_uid &&
194 	    pcred->p_ruid != chgp->p_ucred->cr_uid)
195 		return (EPERM);
196 	if (n > PRIO_MAX)
197 		n = PRIO_MAX;
198 	if (n < PRIO_MIN)
199 		n = PRIO_MIN;
200 	n += NZERO;
201 	if (n < chgp->p_nice && suser(pcred->pc_ucred, &curp->p_acflag))
202 		return (EACCES);
203 	chgp->p_nice = n;
204 	SCHED_LOCK(s);
205 	(void)resetpriority(chgp);
206 	SCHED_UNLOCK(s);
207 	return (0);
208 }
209 
210 /* ARGSUSED */
211 int
212 sys_setrlimit(p, v, retval)
213 	struct proc *p;
214 	void *v;
215 	register_t *retval;
216 {
217 	struct sys_setrlimit_args /* {
218 		syscallarg(int) which;
219 		syscallarg(const struct rlimit *) rlp;
220 	} */ *uap = v;
221 	int which = SCARG(uap, which);
222 	struct rlimit alim;
223 	int error;
224 
225 	error = copyin(SCARG(uap, rlp), &alim, sizeof(struct rlimit));
226 	if (error)
227 		return (error);
228 	return (dosetrlimit(p, p->p_cred, which, &alim));
229 }
230 
231 int
232 dosetrlimit(p, cred, which, limp)
233 	struct proc *p;
234 	struct  pcred *cred;
235 	int which;
236 	struct rlimit *limp;
237 {
238 	struct rlimit *alimp;
239 	extern unsigned maxdmap, maxsmap;
240 	struct plimit *newplim;
241 	int error;
242 
243 	if ((u_int)which >= RLIM_NLIMITS)
244 		return (EINVAL);
245 
246 	if (limp->rlim_cur < 0 || limp->rlim_max < 0)
247 		return (EINVAL);
248 
249 	alimp = &p->p_rlimit[which];
250 	/* if we don't change the value, no need to limcopy() */
251 	if (limp->rlim_cur == alimp->rlim_cur &&
252 	    limp->rlim_max == alimp->rlim_max)
253 		return 0;
254 
255 	if (limp->rlim_cur > alimp->rlim_max ||
256 	    limp->rlim_max > alimp->rlim_max)
257 		if ((error = suser(cred->pc_ucred, &p->p_acflag)) != 0)
258 			return (error);
259 	if (limp->rlim_cur > limp->rlim_max)
260 		limp->rlim_cur = limp->rlim_max;
261 	if (p->p_limit->p_refcnt > 1 &&
262 	    (p->p_limit->p_lflags & PL_SHAREMOD) == 0) {
263 		newplim = limcopy(p->p_limit);
264 		limfree(p->p_limit);
265 		p->p_limit = newplim;
266 		alimp = &p->p_rlimit[which];
267 	}
268 
269 	switch (which) {
270 
271 	case RLIMIT_DATA:
272 		if (limp->rlim_cur > maxdmap)
273 			limp->rlim_cur = maxdmap;
274 		if (limp->rlim_max > maxdmap)
275 			limp->rlim_max = maxdmap;
276 		break;
277 
278 	case RLIMIT_STACK:
279 		if (limp->rlim_cur > maxsmap)
280 			limp->rlim_cur = maxsmap;
281 		if (limp->rlim_max > maxsmap)
282 			limp->rlim_max = maxsmap;
283 
284 		/*
285 		 * Stack is allocated to the max at exec time with
286 		 * only "rlim_cur" bytes accessible (In other words,
287 		 * allocates stack dividing two contiguous regions at
288 		 * "rlim_cur" bytes boundary).
289 		 *
290 		 * Since allocation is done in terms of page, roundup
291 		 * "rlim_cur" (otherwise, contiguous regions
292 		 * overlap).  If stack limit is going up make more
293 		 * accessible, if going down make inaccessible.
294 		 */
295 		limp->rlim_cur = round_page(limp->rlim_cur);
296 		if (limp->rlim_cur != alimp->rlim_cur) {
297 			vaddr_t addr;
298 			vsize_t size;
299 			vm_prot_t prot;
300 
301 			if (limp->rlim_cur > alimp->rlim_cur) {
302 				prot = VM_PROT_ALL;
303 				size = limp->rlim_cur - alimp->rlim_cur;
304 				addr = USRSTACK - limp->rlim_cur;
305 			} else {
306 				prot = VM_PROT_NONE;
307 				size = alimp->rlim_cur - limp->rlim_cur;
308 				addr = USRSTACK - alimp->rlim_cur;
309 			}
310 			(void) uvm_map_protect(&p->p_vmspace->vm_map,
311 					      addr, addr+size, prot, FALSE);
312 		}
313 		break;
314 
315 	case RLIMIT_NOFILE:
316 		if (limp->rlim_cur > maxfiles)
317 			limp->rlim_cur = maxfiles;
318 		if (limp->rlim_max > maxfiles)
319 			limp->rlim_max = maxfiles;
320 		break;
321 
322 	case RLIMIT_NPROC:
323 		if (limp->rlim_cur > maxproc)
324 			limp->rlim_cur = maxproc;
325 		if (limp->rlim_max > maxproc)
326 			limp->rlim_max = maxproc;
327 		break;
328 	}
329 	*alimp = *limp;
330 	return (0);
331 }
332 
333 /* ARGSUSED */
334 int
335 sys_getrlimit(p, v, retval)
336 	struct proc *p;
337 	void *v;
338 	register_t *retval;
339 {
340 	struct sys_getrlimit_args /* {
341 		syscallarg(int) which;
342 		syscallarg(struct rlimit *) rlp;
343 	} */ *uap = v;
344 	int which = SCARG(uap, which);
345 
346 	if ((u_int)which >= RLIM_NLIMITS)
347 		return (EINVAL);
348 	return (copyout(&p->p_rlimit[which], SCARG(uap, rlp),
349 	    sizeof(struct rlimit)));
350 }
351 
352 /*
353  * Transform the running time and tick information in proc p into user,
354  * system, and interrupt time usage.
355  */
356 void
357 calcru(p, up, sp, ip)
358 	struct proc *p;
359 	struct timeval *up;
360 	struct timeval *sp;
361 	struct timeval *ip;
362 {
363 	u_quad_t u, st, ut, it, tot;
364 	long sec, usec;
365 	int s;
366 	struct timeval tv;
367 
368 	s = splstatclock();
369 	st = p->p_sticks;
370 	ut = p->p_uticks;
371 	it = p->p_iticks;
372 	splx(s);
373 
374 	tot = st + ut + it;
375 	if (tot == 0) {
376 		up->tv_sec = up->tv_usec = 0;
377 		sp->tv_sec = sp->tv_usec = 0;
378 		if (ip != NULL)
379 			ip->tv_sec = ip->tv_usec = 0;
380 		return;
381 	}
382 
383 	sec = p->p_rtime.tv_sec;
384 	usec = p->p_rtime.tv_usec;
385 	if (p->p_stat == SONPROC) {
386 		struct schedstate_percpu *spc;
387 
388 		KDASSERT(p->p_cpu != NULL);
389 		spc = &p->p_cpu->ci_schedstate;
390 
391 		/*
392 		 * Adjust for the current time slice.  This is actually fairly
393 		 * important since the error here is on the order of a time
394 		 * quantum, which is much greater than the sampling error.
395 		 */
396 		microtime(&tv);
397 		sec += tv.tv_sec - spc->spc_runtime.tv_sec;
398 		usec += tv.tv_usec - spc->spc_runtime.tv_usec;
399 	}
400 	u = (u_quad_t) sec * 1000000 + usec;
401 	st = (u * st) / tot;
402 	sp->tv_sec = st / 1000000;
403 	sp->tv_usec = st % 1000000;
404 	ut = (u * ut) / tot;
405 	up->tv_sec = ut / 1000000;
406 	up->tv_usec = ut % 1000000;
407 	if (ip != NULL) {
408 		it = (u * it) / tot;
409 		ip->tv_sec = it / 1000000;
410 		ip->tv_usec = it % 1000000;
411 	}
412 }
413 
414 /* ARGSUSED */
415 int
416 sys_getrusage(p, v, retval)
417 	struct proc *p;
418 	void *v;
419 	register_t *retval;
420 {
421 	struct sys_getrusage_args /* {
422 		syscallarg(int) who;
423 		syscallarg(struct rusage *) rusage;
424 	} */ *uap = v;
425 	struct rusage *rup;
426 
427 	switch (SCARG(uap, who)) {
428 
429 	case RUSAGE_SELF:
430 		rup = &p->p_stats->p_ru;
431 		calcru(p, &rup->ru_utime, &rup->ru_stime, NULL);
432 		break;
433 
434 	case RUSAGE_CHILDREN:
435 		rup = &p->p_stats->p_cru;
436 		break;
437 
438 	default:
439 		return (EINVAL);
440 	}
441 	return (copyout(rup, SCARG(uap, rusage), sizeof(struct rusage)));
442 }
443 
444 void
445 ruadd(ru, ru2)
446 	struct rusage *ru, *ru2;
447 {
448 	long *ip, *ip2;
449 	int i;
450 
451 	timeradd(&ru->ru_utime, &ru2->ru_utime, &ru->ru_utime);
452 	timeradd(&ru->ru_stime, &ru2->ru_stime, &ru->ru_stime);
453 	if (ru->ru_maxrss < ru2->ru_maxrss)
454 		ru->ru_maxrss = ru2->ru_maxrss;
455 	ip = &ru->ru_first; ip2 = &ru2->ru_first;
456 	for (i = &ru->ru_last - &ru->ru_first; i >= 0; i--)
457 		*ip++ += *ip2++;
458 }
459 
460 /*
461  * Make a copy of the plimit structure.
462  * We share these structures copy-on-write after fork,
463  * and copy when a limit is changed.
464  */
465 struct plimit *
466 limcopy(lim)
467 	struct plimit *lim;
468 {
469 	struct plimit *newlim;
470 
471 	newlim = pool_get(&plimit_pool, PR_WAITOK);
472 	memcpy(newlim->pl_rlimit, lim->pl_rlimit,
473 	    sizeof(struct rlimit) * RLIM_NLIMITS);
474 	if (lim->pl_corename == defcorename) {
475 		newlim->pl_corename = defcorename;
476 	} else {
477 		newlim->pl_corename = malloc(strlen(lim->pl_corename)+1,
478 		    M_TEMP, M_WAITOK);
479 		strcpy(newlim->pl_corename, lim->pl_corename);
480 	}
481 	newlim->p_lflags = 0;
482 	newlim->p_refcnt = 1;
483 	return (newlim);
484 }
485 
486 void
487 limfree(lim)
488 	struct plimit *lim;
489 {
490 
491 	if (--lim->p_refcnt > 0)
492 		return;
493 #ifdef DIAGNOSTIC
494 	if (lim->p_refcnt < 0)
495 		panic("limfree");
496 #endif
497 	if (lim->pl_corename != defcorename)
498 		free(lim->pl_corename, M_TEMP);
499 	pool_put(&plimit_pool, lim);
500 }
501