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kern_resource.c revision 1.37
      1 /*	$NetBSD: kern_resource.c,v 1.37 1996/10/02 18:05:03 ws 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 = 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 		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 == NZERO + PRIO_MAX + 1)
    113 		return (ESRCH);
    114 	*retval = low - NZERO;
    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 	n += NZERO;
    195 	if (n < chgp->p_nice && suser(pcred->pc_ucred, &curp->p_acflag))
    196 		return (EACCES);
    197 	chgp->p_nice = n;
    198 	(void)resetpriority(chgp);
    199 	return (0);
    200 }
    201 
    202 /* ARGSUSED */
    203 int
    204 sys_setrlimit(p, v, retval)
    205 	struct proc *p;
    206 	void *v;
    207 	register_t *retval;
    208 {
    209 	register struct sys_setrlimit_args /* {
    210 		syscallarg(u_int) which;
    211 		syscallarg(struct rlimit *) rlp;
    212 	} */ *uap = v;
    213 	struct rlimit alim;
    214 	int error;
    215 
    216 	error = copyin((caddr_t)SCARG(uap, rlp), (caddr_t)&alim,
    217 		       sizeof (struct rlimit));
    218 	if (error)
    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)) != 0)
    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 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 = (u_quad_t) 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 *newlim;
    439 
    440 	MALLOC(newlim, struct plimit *, sizeof(struct plimit),
    441 	    M_SUBPROC, M_WAITOK);
    442 	bcopy(lim->pl_rlimit, newlim->pl_rlimit,
    443 	    sizeof(struct rlimit) * RLIM_NLIMITS);
    444 	newlim->p_lflags = 0;
    445 	newlim->p_refcnt = 1;
    446 	return (newlim);
    447 }
    448 
    449 void
    450 limfree(lim)
    451 	struct plimit *lim;
    452 {
    453 
    454 	if (--lim->p_refcnt > 0)
    455 		return;
    456 	FREE(lim, M_SUBPROC);
    457 }
    458