kern_resource.c revision 1.63 1 /* $NetBSD: kern_resource.c,v 1.63 2002/08/25 21:44:13 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/cdefs.h>
44 __KERNEL_RCSID(0, "$NetBSD: kern_resource.c,v 1.63 2002/08/25 21:44:13 thorpej Exp $");
45
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/kernel.h>
49 #include <sys/file.h>
50 #include <sys/resourcevar.h>
51 #include <sys/malloc.h>
52 #include <sys/pool.h>
53 #include <sys/proc.h>
54
55 #include <sys/mount.h>
56 #include <sys/syscallargs.h>
57
58 #include <uvm/uvm_extern.h>
59
60 /*
61 * Maximum process data and stack limits.
62 * They are variables so they are patchable.
63 *
64 * XXXX Do we really need them to be patchable?
65 */
66 rlim_t maxdmap = MAXDSIZ;
67 rlim_t maxsmap = MAXSSIZ;
68
69 /*
70 * Resource controls and accounting.
71 */
72
73 int
74 sys_getpriority(curp, v, retval)
75 struct proc *curp;
76 void *v;
77 register_t *retval;
78 {
79 struct sys_getpriority_args /* {
80 syscallarg(int) which;
81 syscallarg(int) who;
82 } */ *uap = v;
83 struct proc *p;
84 int low = NZERO + PRIO_MAX + 1;
85
86 switch (SCARG(uap, which)) {
87
88 case PRIO_PROCESS:
89 if (SCARG(uap, who) == 0)
90 p = curp;
91 else
92 p = pfind(SCARG(uap, who));
93 if (p == 0)
94 break;
95 low = p->p_nice;
96 break;
97
98 case PRIO_PGRP: {
99 struct pgrp *pg;
100
101 if (SCARG(uap, who) == 0)
102 pg = curp->p_pgrp;
103 else if ((pg = pgfind(SCARG(uap, who))) == NULL)
104 break;
105 for (p = pg->pg_members.lh_first; p != 0;
106 p = p->p_pglist.le_next) {
107 if (p->p_nice < low)
108 low = p->p_nice;
109 }
110 break;
111 }
112
113 case PRIO_USER:
114 if (SCARG(uap, who) == 0)
115 SCARG(uap, who) = curp->p_ucred->cr_uid;
116 proclist_lock_read();
117 for (p = allproc.lh_first; p != 0; p = p->p_list.le_next)
118 if (p->p_ucred->cr_uid == (uid_t) SCARG(uap, who) &&
119 p->p_nice < low)
120 low = p->p_nice;
121 proclist_unlock_read();
122 break;
123
124 default:
125 return (EINVAL);
126 }
127 if (low == NZERO + PRIO_MAX + 1)
128 return (ESRCH);
129 *retval = low - NZERO;
130 return (0);
131 }
132
133 /* ARGSUSED */
134 int
135 sys_setpriority(curp, v, retval)
136 struct proc *curp;
137 void *v;
138 register_t *retval;
139 {
140 struct sys_setpriority_args /* {
141 syscallarg(int) which;
142 syscallarg(int) who;
143 syscallarg(int) prio;
144 } */ *uap = v;
145 struct proc *p;
146 int found = 0, error = 0;
147
148 switch (SCARG(uap, which)) {
149
150 case PRIO_PROCESS:
151 if (SCARG(uap, who) == 0)
152 p = curp;
153 else
154 p = pfind(SCARG(uap, who));
155 if (p == 0)
156 break;
157 error = donice(curp, p, SCARG(uap, prio));
158 found++;
159 break;
160
161 case PRIO_PGRP: {
162 struct pgrp *pg;
163
164 if (SCARG(uap, who) == 0)
165 pg = curp->p_pgrp;
166 else if ((pg = pgfind(SCARG(uap, who))) == NULL)
167 break;
168 for (p = pg->pg_members.lh_first; p != 0;
169 p = p->p_pglist.le_next) {
170 error = donice(curp, p, SCARG(uap, prio));
171 found++;
172 }
173 break;
174 }
175
176 case PRIO_USER:
177 if (SCARG(uap, who) == 0)
178 SCARG(uap, who) = curp->p_ucred->cr_uid;
179 proclist_lock_read();
180 for (p = allproc.lh_first; p != 0; p = p->p_list.le_next)
181 if (p->p_ucred->cr_uid == (uid_t) SCARG(uap, who)) {
182 error = donice(curp, p, SCARG(uap, prio));
183 found++;
184 }
185 proclist_unlock_read();
186 break;
187
188 default:
189 return (EINVAL);
190 }
191 if (found == 0)
192 return (ESRCH);
193 return (error);
194 }
195
196 int
197 donice(curp, chgp, n)
198 struct proc *curp, *chgp;
199 int n;
200 {
201 struct pcred *pcred = curp->p_cred;
202 int s;
203
204 if (pcred->pc_ucred->cr_uid && pcred->p_ruid &&
205 pcred->pc_ucred->cr_uid != chgp->p_ucred->cr_uid &&
206 pcred->p_ruid != chgp->p_ucred->cr_uid)
207 return (EPERM);
208 if (n > PRIO_MAX)
209 n = PRIO_MAX;
210 if (n < PRIO_MIN)
211 n = PRIO_MIN;
212 n += NZERO;
213 if (n < chgp->p_nice && suser(pcred->pc_ucred, &curp->p_acflag))
214 return (EACCES);
215 chgp->p_nice = n;
216 SCHED_LOCK(s);
217 (void)resetpriority(chgp);
218 SCHED_UNLOCK(s);
219 return (0);
220 }
221
222 /* ARGSUSED */
223 int
224 sys_setrlimit(p, v, retval)
225 struct proc *p;
226 void *v;
227 register_t *retval;
228 {
229 struct sys_setrlimit_args /* {
230 syscallarg(int) which;
231 syscallarg(const struct rlimit *) rlp;
232 } */ *uap = v;
233 int which = SCARG(uap, which);
234 struct rlimit alim;
235 int error;
236
237 error = copyin(SCARG(uap, rlp), &alim, sizeof(struct rlimit));
238 if (error)
239 return (error);
240 return (dosetrlimit(p, p->p_cred, which, &alim));
241 }
242
243 int
244 dosetrlimit(p, cred, which, limp)
245 struct proc *p;
246 struct pcred *cred;
247 int which;
248 struct rlimit *limp;
249 {
250 struct rlimit *alimp;
251 struct plimit *newplim;
252 int error;
253
254 if ((u_int)which >= RLIM_NLIMITS)
255 return (EINVAL);
256
257 if (limp->rlim_cur < 0 || limp->rlim_max < 0)
258 return (EINVAL);
259
260 alimp = &p->p_rlimit[which];
261 /* if we don't change the value, no need to limcopy() */
262 if (limp->rlim_cur == alimp->rlim_cur &&
263 limp->rlim_max == alimp->rlim_max)
264 return 0;
265
266 if (limp->rlim_cur > limp->rlim_max) {
267 /*
268 * This is programming error. According to SUSv2, we should
269 * return error in this case.
270 */
271 return (EINVAL);
272 }
273 if (limp->rlim_max > alimp->rlim_max
274 && (error = suser(cred->pc_ucred, &p->p_acflag)) != 0)
275 return (error);
276
277 if (p->p_limit->p_refcnt > 1 &&
278 (p->p_limit->p_lflags & PL_SHAREMOD) == 0) {
279 newplim = limcopy(p->p_limit);
280 limfree(p->p_limit);
281 p->p_limit = newplim;
282 alimp = &p->p_rlimit[which];
283 }
284
285 switch (which) {
286
287 case RLIMIT_DATA:
288 if (limp->rlim_cur > maxdmap)
289 limp->rlim_cur = maxdmap;
290 if (limp->rlim_max > maxdmap)
291 limp->rlim_max = maxdmap;
292 break;
293
294 case RLIMIT_STACK:
295 if (limp->rlim_cur > maxsmap)
296 limp->rlim_cur = maxsmap;
297 if (limp->rlim_max > maxsmap)
298 limp->rlim_max = maxsmap;
299
300 /*
301 * Return EINVAL if the new stack size limit is lower than
302 * current usage. Otherwise, the process would get SIGSEGV the
303 * moment it would try to access anything on it's current stack.
304 * This conforms to SUSv2.
305 */
306 if (limp->rlim_cur < p->p_vmspace->vm_ssize * PAGE_SIZE
307 || limp->rlim_max < p->p_vmspace->vm_ssize * PAGE_SIZE)
308 return (EINVAL);
309
310 /*
311 * Stack is allocated to the max at exec time with
312 * only "rlim_cur" bytes accessible (In other words,
313 * allocates stack dividing two contiguous regions at
314 * "rlim_cur" bytes boundary).
315 *
316 * Since allocation is done in terms of page, roundup
317 * "rlim_cur" (otherwise, contiguous regions
318 * overlap). If stack limit is going up make more
319 * accessible, if going down make inaccessible.
320 */
321 limp->rlim_cur = round_page(limp->rlim_cur);
322 if (limp->rlim_cur != alimp->rlim_cur) {
323 vaddr_t addr;
324 vsize_t size;
325 vm_prot_t prot;
326
327 if (limp->rlim_cur > alimp->rlim_cur) {
328 prot = VM_PROT_ALL;
329 size = limp->rlim_cur - alimp->rlim_cur;
330 addr = USRSTACK - limp->rlim_cur;
331 } else {
332 prot = VM_PROT_NONE;
333 size = alimp->rlim_cur - limp->rlim_cur;
334 addr = USRSTACK - alimp->rlim_cur;
335 }
336 (void) uvm_map_protect(&p->p_vmspace->vm_map,
337 addr, addr+size, prot, FALSE);
338 }
339 break;
340
341 case RLIMIT_NOFILE:
342 if (limp->rlim_cur > maxfiles)
343 limp->rlim_cur = maxfiles;
344 if (limp->rlim_max > maxfiles)
345 limp->rlim_max = maxfiles;
346 break;
347
348 case RLIMIT_NPROC:
349 if (limp->rlim_cur > maxproc)
350 limp->rlim_cur = maxproc;
351 if (limp->rlim_max > maxproc)
352 limp->rlim_max = maxproc;
353 break;
354 }
355 *alimp = *limp;
356 return (0);
357 }
358
359 /* ARGSUSED */
360 int
361 sys_getrlimit(p, v, retval)
362 struct proc *p;
363 void *v;
364 register_t *retval;
365 {
366 struct sys_getrlimit_args /* {
367 syscallarg(int) which;
368 syscallarg(struct rlimit *) rlp;
369 } */ *uap = v;
370 int which = SCARG(uap, which);
371
372 if ((u_int)which >= RLIM_NLIMITS)
373 return (EINVAL);
374 return (copyout(&p->p_rlimit[which], SCARG(uap, rlp),
375 sizeof(struct rlimit)));
376 }
377
378 /*
379 * Transform the running time and tick information in proc p into user,
380 * system, and interrupt time usage.
381 */
382 void
383 calcru(p, up, sp, ip)
384 struct proc *p;
385 struct timeval *up;
386 struct timeval *sp;
387 struct timeval *ip;
388 {
389 u_quad_t u, st, ut, it, tot;
390 long sec, usec;
391 int s;
392 struct timeval tv;
393
394 s = splstatclock();
395 st = p->p_sticks;
396 ut = p->p_uticks;
397 it = p->p_iticks;
398 splx(s);
399
400 tot = st + ut + it;
401 if (tot == 0) {
402 up->tv_sec = up->tv_usec = 0;
403 sp->tv_sec = sp->tv_usec = 0;
404 if (ip != NULL)
405 ip->tv_sec = ip->tv_usec = 0;
406 return;
407 }
408
409 sec = p->p_rtime.tv_sec;
410 usec = p->p_rtime.tv_usec;
411 if (p->p_stat == SONPROC) {
412 struct schedstate_percpu *spc;
413
414 KDASSERT(p->p_cpu != NULL);
415 spc = &p->p_cpu->ci_schedstate;
416
417 /*
418 * Adjust for the current time slice. This is actually fairly
419 * important since the error here is on the order of a time
420 * quantum, which is much greater than the sampling error.
421 */
422 microtime(&tv);
423 sec += tv.tv_sec - spc->spc_runtime.tv_sec;
424 usec += tv.tv_usec - spc->spc_runtime.tv_usec;
425 }
426 u = (u_quad_t) sec * 1000000 + usec;
427 st = (u * st) / tot;
428 sp->tv_sec = st / 1000000;
429 sp->tv_usec = st % 1000000;
430 ut = (u * ut) / tot;
431 up->tv_sec = ut / 1000000;
432 up->tv_usec = ut % 1000000;
433 if (ip != NULL) {
434 it = (u * it) / tot;
435 ip->tv_sec = it / 1000000;
436 ip->tv_usec = it % 1000000;
437 }
438 }
439
440 /* ARGSUSED */
441 int
442 sys_getrusage(p, v, retval)
443 struct proc *p;
444 void *v;
445 register_t *retval;
446 {
447 struct sys_getrusage_args /* {
448 syscallarg(int) who;
449 syscallarg(struct rusage *) rusage;
450 } */ *uap = v;
451 struct rusage *rup;
452
453 switch (SCARG(uap, who)) {
454
455 case RUSAGE_SELF:
456 rup = &p->p_stats->p_ru;
457 calcru(p, &rup->ru_utime, &rup->ru_stime, NULL);
458 break;
459
460 case RUSAGE_CHILDREN:
461 rup = &p->p_stats->p_cru;
462 break;
463
464 default:
465 return (EINVAL);
466 }
467 return (copyout(rup, SCARG(uap, rusage), sizeof(struct rusage)));
468 }
469
470 void
471 ruadd(ru, ru2)
472 struct rusage *ru, *ru2;
473 {
474 long *ip, *ip2;
475 int i;
476
477 timeradd(&ru->ru_utime, &ru2->ru_utime, &ru->ru_utime);
478 timeradd(&ru->ru_stime, &ru2->ru_stime, &ru->ru_stime);
479 if (ru->ru_maxrss < ru2->ru_maxrss)
480 ru->ru_maxrss = ru2->ru_maxrss;
481 ip = &ru->ru_first; ip2 = &ru2->ru_first;
482 for (i = &ru->ru_last - &ru->ru_first; i >= 0; i--)
483 *ip++ += *ip2++;
484 }
485
486 /*
487 * Make a copy of the plimit structure.
488 * We share these structures copy-on-write after fork,
489 * and copy when a limit is changed.
490 */
491 struct plimit *
492 limcopy(lim)
493 struct plimit *lim;
494 {
495 struct plimit *newlim;
496
497 newlim = pool_get(&plimit_pool, PR_WAITOK);
498 memcpy(newlim->pl_rlimit, lim->pl_rlimit,
499 sizeof(struct rlimit) * RLIM_NLIMITS);
500 if (lim->pl_corename == defcorename) {
501 newlim->pl_corename = defcorename;
502 } else {
503 newlim->pl_corename = malloc(strlen(lim->pl_corename)+1,
504 M_TEMP, M_WAITOK);
505 strcpy(newlim->pl_corename, lim->pl_corename);
506 }
507 newlim->p_lflags = 0;
508 newlim->p_refcnt = 1;
509 return (newlim);
510 }
511
512 void
513 limfree(lim)
514 struct plimit *lim;
515 {
516
517 if (--lim->p_refcnt > 0)
518 return;
519 #ifdef DIAGNOSTIC
520 if (lim->p_refcnt < 0)
521 panic("limfree");
522 #endif
523 if (lim->pl_corename != defcorename)
524 free(lim->pl_corename, M_TEMP);
525 pool_put(&plimit_pool, lim);
526 }
527