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Diffstat (limited to 'freebsd/sys/kern/kern_resource.c')
| -rw-r--r-- | freebsd/sys/kern/kern_resource.c | 1539 |
1 files changed, 1539 insertions, 0 deletions
diff --git a/freebsd/sys/kern/kern_resource.c b/freebsd/sys/kern/kern_resource.c new file mode 100644 index 00000000..49b1e0fe --- /dev/null +++ b/freebsd/sys/kern/kern_resource.c @@ -0,0 +1,1539 @@ +/*- + * SPDX-License-Identifier: BSD-3-Clause + * + * Copyright (c) 1982, 1986, 1991, 1993 + * The Regents of the University of California. All rights reserved. + * (c) UNIX System Laboratories, Inc. + * All or some portions of this file are derived from material licensed + * to the University of California by American Telephone and Telegraph + * Co. or Unix System Laboratories, Inc. and are reproduced herein with + * the permission of UNIX System Laboratories, Inc. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * @(#)kern_resource.c 8.5 (Berkeley) 1/21/94 + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/sysproto.h> +#include <sys/file.h> +#include <sys/kernel.h> +#include <sys/lock.h> +#include <sys/malloc.h> +#include <sys/mutex.h> +#include <sys/priv.h> +#include <sys/proc.h> +#include <sys/refcount.h> +#include <sys/racct.h> +#include <sys/resourcevar.h> +#include <sys/rwlock.h> +#include <sys/sched.h> +#include <sys/sx.h> +#include <sys/syscallsubr.h> +#include <sys/sysctl.h> +#include <sys/sysent.h> +#include <sys/time.h> +#include <sys/umtx.h> + +#include <vm/vm.h> +#include <vm/vm_param.h> +#include <vm/pmap.h> +#include <vm/vm_map.h> + + +static MALLOC_DEFINE(M_PLIMIT, "plimit", "plimit structures"); +static MALLOC_DEFINE(M_UIDINFO, "uidinfo", "uidinfo structures"); +#define UIHASH(uid) (&uihashtbl[(uid) & uihash]) +static struct rwlock uihashtbl_lock; +static LIST_HEAD(uihashhead, uidinfo) *uihashtbl; +static u_long uihash; /* size of hash table - 1 */ + +static void calcru1(struct proc *p, struct rusage_ext *ruxp, + struct timeval *up, struct timeval *sp); +static int donice(struct thread *td, struct proc *chgp, int n); +static struct uidinfo *uilookup(uid_t uid); +static void ruxagg_locked(struct rusage_ext *rux, struct thread *td); + +/* + * Resource controls and accounting. + */ +#ifndef _SYS_SYSPROTO_H_ +struct getpriority_args { + int which; + int who; +}; +#endif +int +sys_getpriority(struct thread *td, struct getpriority_args *uap) +{ + struct proc *p; + struct pgrp *pg; + int error, low; + + error = 0; + low = PRIO_MAX + 1; + switch (uap->which) { + + case PRIO_PROCESS: + if (uap->who == 0) + low = td->td_proc->p_nice; + else { + p = pfind(uap->who); + if (p == NULL) + break; + if (p_cansee(td, p) == 0) + low = p->p_nice; + PROC_UNLOCK(p); + } + break; + + case PRIO_PGRP: + sx_slock(&proctree_lock); + if (uap->who == 0) { + pg = td->td_proc->p_pgrp; + PGRP_LOCK(pg); + } else { + pg = pgfind(uap->who); + if (pg == NULL) { + sx_sunlock(&proctree_lock); + break; + } + } + sx_sunlock(&proctree_lock); + LIST_FOREACH(p, &pg->pg_members, p_pglist) { + PROC_LOCK(p); + if (p->p_state == PRS_NORMAL && + p_cansee(td, p) == 0) { + if (p->p_nice < low) + low = p->p_nice; + } + PROC_UNLOCK(p); + } + PGRP_UNLOCK(pg); + break; + + case PRIO_USER: + if (uap->who == 0) + uap->who = td->td_ucred->cr_uid; + sx_slock(&allproc_lock); + FOREACH_PROC_IN_SYSTEM(p) { + PROC_LOCK(p); + if (p->p_state == PRS_NORMAL && + p_cansee(td, p) == 0 && + p->p_ucred->cr_uid == uap->who) { + if (p->p_nice < low) + low = p->p_nice; + } + PROC_UNLOCK(p); + } + sx_sunlock(&allproc_lock); + break; + + default: + error = EINVAL; + break; + } + if (low == PRIO_MAX + 1 && error == 0) + error = ESRCH; + td->td_retval[0] = low; + return (error); +} + +#ifndef _SYS_SYSPROTO_H_ +struct setpriority_args { + int which; + int who; + int prio; +}; +#endif +int +sys_setpriority(struct thread *td, struct setpriority_args *uap) +{ + struct proc *curp, *p; + struct pgrp *pg; + int found = 0, error = 0; + + curp = td->td_proc; + switch (uap->which) { + case PRIO_PROCESS: + if (uap->who == 0) { + PROC_LOCK(curp); + error = donice(td, curp, uap->prio); + PROC_UNLOCK(curp); + } else { + p = pfind(uap->who); + if (p == NULL) + break; + error = p_cansee(td, p); + if (error == 0) + error = donice(td, p, uap->prio); + PROC_UNLOCK(p); + } + found++; + break; + + case PRIO_PGRP: + sx_slock(&proctree_lock); + if (uap->who == 0) { + pg = curp->p_pgrp; + PGRP_LOCK(pg); + } else { + pg = pgfind(uap->who); + if (pg == NULL) { + sx_sunlock(&proctree_lock); + break; + } + } + sx_sunlock(&proctree_lock); + LIST_FOREACH(p, &pg->pg_members, p_pglist) { + PROC_LOCK(p); + if (p->p_state == PRS_NORMAL && + p_cansee(td, p) == 0) { + error = donice(td, p, uap->prio); + found++; + } + PROC_UNLOCK(p); + } + PGRP_UNLOCK(pg); + break; + + case PRIO_USER: + if (uap->who == 0) + uap->who = td->td_ucred->cr_uid; + sx_slock(&allproc_lock); + FOREACH_PROC_IN_SYSTEM(p) { + PROC_LOCK(p); + if (p->p_state == PRS_NORMAL && + p->p_ucred->cr_uid == uap->who && + p_cansee(td, p) == 0) { + error = donice(td, p, uap->prio); + found++; + } + PROC_UNLOCK(p); + } + sx_sunlock(&allproc_lock); + break; + + default: + error = EINVAL; + break; + } + if (found == 0 && error == 0) + error = ESRCH; + return (error); +} + +/* + * Set "nice" for a (whole) process. + */ +static int +donice(struct thread *td, struct proc *p, int n) +{ + int error; + + PROC_LOCK_ASSERT(p, MA_OWNED); + if ((error = p_cansched(td, p))) + return (error); + if (n > PRIO_MAX) + n = PRIO_MAX; + if (n < PRIO_MIN) + n = PRIO_MIN; + if (n < p->p_nice && priv_check(td, PRIV_SCHED_SETPRIORITY) != 0) + return (EACCES); + sched_nice(p, n); + return (0); +} + +static int unprivileged_idprio; +SYSCTL_INT(_security_bsd, OID_AUTO, unprivileged_idprio, CTLFLAG_RW, + &unprivileged_idprio, 0, "Allow non-root users to set an idle priority"); + +/* + * Set realtime priority for LWP. + */ +#ifndef _SYS_SYSPROTO_H_ +struct rtprio_thread_args { + int function; + lwpid_t lwpid; + struct rtprio *rtp; +}; +#endif +int +sys_rtprio_thread(struct thread *td, struct rtprio_thread_args *uap) +{ + struct proc *p; + struct rtprio rtp; + struct thread *td1; + int cierror, error; + + /* Perform copyin before acquiring locks if needed. */ + if (uap->function == RTP_SET) + cierror = copyin(uap->rtp, &rtp, sizeof(struct rtprio)); + else + cierror = 0; + + if (uap->lwpid == 0 || uap->lwpid == td->td_tid) { + p = td->td_proc; + td1 = td; + PROC_LOCK(p); + } else { + /* Only look up thread in current process */ + td1 = tdfind(uap->lwpid, curproc->p_pid); + if (td1 == NULL) + return (ESRCH); + p = td1->td_proc; + } + + switch (uap->function) { + case RTP_LOOKUP: + if ((error = p_cansee(td, p))) + break; + pri_to_rtp(td1, &rtp); + PROC_UNLOCK(p); + return (copyout(&rtp, uap->rtp, sizeof(struct rtprio))); + case RTP_SET: + if ((error = p_cansched(td, p)) || (error = cierror)) + break; + + /* Disallow setting rtprio in most cases if not superuser. */ + + /* + * Realtime priority has to be restricted for reasons which + * should be obvious. However, for idleprio processes, there is + * a potential for system deadlock if an idleprio process gains + * a lock on a resource that other processes need (and the + * idleprio process can't run due to a CPU-bound normal + * process). Fix me! XXX + * + * This problem is not only related to idleprio process. + * A user level program can obtain a file lock and hold it + * indefinitely. Additionally, without idleprio processes it is + * still conceivable that a program with low priority will never + * get to run. In short, allowing this feature might make it + * easier to lock a resource indefinitely, but it is not the + * only thing that makes it possible. + */ + if (RTP_PRIO_BASE(rtp.type) == RTP_PRIO_REALTIME || + (RTP_PRIO_BASE(rtp.type) == RTP_PRIO_IDLE && + unprivileged_idprio == 0)) { + error = priv_check(td, PRIV_SCHED_RTPRIO); + if (error) + break; + } + error = rtp_to_pri(&rtp, td1); + break; + default: + error = EINVAL; + break; + } + PROC_UNLOCK(p); + return (error); +} + +/* + * Set realtime priority. + */ +#ifndef _SYS_SYSPROTO_H_ +struct rtprio_args { + int function; + pid_t pid; + struct rtprio *rtp; +}; +#endif +int +sys_rtprio(struct thread *td, struct rtprio_args *uap) +{ + struct proc *p; + struct thread *tdp; + struct rtprio rtp; + int cierror, error; + + /* Perform copyin before acquiring locks if needed. */ + if (uap->function == RTP_SET) + cierror = copyin(uap->rtp, &rtp, sizeof(struct rtprio)); + else + cierror = 0; + + if (uap->pid == 0) { + p = td->td_proc; + PROC_LOCK(p); + } else { + p = pfind(uap->pid); + if (p == NULL) + return (ESRCH); + } + + switch (uap->function) { + case RTP_LOOKUP: + if ((error = p_cansee(td, p))) + break; + /* + * Return OUR priority if no pid specified, + * or if one is, report the highest priority + * in the process. There isn't much more you can do as + * there is only room to return a single priority. + * Note: specifying our own pid is not the same + * as leaving it zero. + */ + if (uap->pid == 0) { + pri_to_rtp(td, &rtp); + } else { + struct rtprio rtp2; + + rtp.type = RTP_PRIO_IDLE; + rtp.prio = RTP_PRIO_MAX; + FOREACH_THREAD_IN_PROC(p, tdp) { + pri_to_rtp(tdp, &rtp2); + if (rtp2.type < rtp.type || + (rtp2.type == rtp.type && + rtp2.prio < rtp.prio)) { + rtp.type = rtp2.type; + rtp.prio = rtp2.prio; + } + } + } + PROC_UNLOCK(p); + return (copyout(&rtp, uap->rtp, sizeof(struct rtprio))); + case RTP_SET: + if ((error = p_cansched(td, p)) || (error = cierror)) + break; + + /* + * Disallow setting rtprio in most cases if not superuser. + * See the comment in sys_rtprio_thread about idprio + * threads holding a lock. + */ + if (RTP_PRIO_BASE(rtp.type) == RTP_PRIO_REALTIME || + (RTP_PRIO_BASE(rtp.type) == RTP_PRIO_IDLE && + !unprivileged_idprio)) { + error = priv_check(td, PRIV_SCHED_RTPRIO); + if (error) + break; + } + + /* + * If we are setting our own priority, set just our + * thread but if we are doing another process, + * do all the threads on that process. If we + * specify our own pid we do the latter. + */ + if (uap->pid == 0) { + error = rtp_to_pri(&rtp, td); + } else { + FOREACH_THREAD_IN_PROC(p, td) { + if ((error = rtp_to_pri(&rtp, td)) != 0) + break; + } + } + break; + default: + error = EINVAL; + break; + } + PROC_UNLOCK(p); + return (error); +} + +int +rtp_to_pri(struct rtprio *rtp, struct thread *td) +{ + u_char newpri, oldclass, oldpri; + + switch (RTP_PRIO_BASE(rtp->type)) { + case RTP_PRIO_REALTIME: + if (rtp->prio > RTP_PRIO_MAX) + return (EINVAL); + newpri = PRI_MIN_REALTIME + rtp->prio; + break; + case RTP_PRIO_NORMAL: + if (rtp->prio > (PRI_MAX_TIMESHARE - PRI_MIN_TIMESHARE)) + return (EINVAL); + newpri = PRI_MIN_TIMESHARE + rtp->prio; + break; + case RTP_PRIO_IDLE: + if (rtp->prio > RTP_PRIO_MAX) + return (EINVAL); + newpri = PRI_MIN_IDLE + rtp->prio; + break; + default: + return (EINVAL); + } + + thread_lock(td); + oldclass = td->td_pri_class; + sched_class(td, rtp->type); /* XXX fix */ + oldpri = td->td_user_pri; + sched_user_prio(td, newpri); + if (td->td_user_pri != oldpri && (oldclass != RTP_PRIO_NORMAL || + td->td_pri_class != RTP_PRIO_NORMAL)) + sched_prio(td, td->td_user_pri); + if (TD_ON_UPILOCK(td) && oldpri != newpri) { + critical_enter(); + thread_unlock(td); + umtx_pi_adjust(td, oldpri); + critical_exit(); + } else + thread_unlock(td); + return (0); +} + +void +pri_to_rtp(struct thread *td, struct rtprio *rtp) +{ + + thread_lock(td); + switch (PRI_BASE(td->td_pri_class)) { + case PRI_REALTIME: + rtp->prio = td->td_base_user_pri - PRI_MIN_REALTIME; + break; + case PRI_TIMESHARE: + rtp->prio = td->td_base_user_pri - PRI_MIN_TIMESHARE; + break; + case PRI_IDLE: + rtp->prio = td->td_base_user_pri - PRI_MIN_IDLE; + break; + default: + break; + } + rtp->type = td->td_pri_class; + thread_unlock(td); +} + +#if defined(COMPAT_43) +#ifndef _SYS_SYSPROTO_H_ +struct osetrlimit_args { + u_int which; + struct orlimit *rlp; +}; +#endif +int +osetrlimit(struct thread *td, struct osetrlimit_args *uap) +{ + struct orlimit olim; + struct rlimit lim; + int error; + + if ((error = copyin(uap->rlp, &olim, sizeof(struct orlimit)))) + return (error); + lim.rlim_cur = olim.rlim_cur; + lim.rlim_max = olim.rlim_max; + error = kern_setrlimit(td, uap->which, &lim); + return (error); +} + +#ifndef _SYS_SYSPROTO_H_ +struct ogetrlimit_args { + u_int which; + struct orlimit *rlp; +}; +#endif +int +ogetrlimit(struct thread *td, struct ogetrlimit_args *uap) +{ + struct orlimit olim; + struct rlimit rl; + int error; + + if (uap->which >= RLIM_NLIMITS) + return (EINVAL); + lim_rlimit(td, uap->which, &rl); + + /* + * XXX would be more correct to convert only RLIM_INFINITY to the + * old RLIM_INFINITY and fail with EOVERFLOW for other larger + * values. Most 64->32 and 32->16 conversions, including not + * unimportant ones of uids are even more broken than what we + * do here (they blindly truncate). We don't do this correctly + * here since we have little experience with EOVERFLOW yet. + * Elsewhere, getuid() can't fail... + */ + olim.rlim_cur = rl.rlim_cur > 0x7fffffff ? 0x7fffffff : rl.rlim_cur; + olim.rlim_max = rl.rlim_max > 0x7fffffff ? 0x7fffffff : rl.rlim_max; + error = copyout(&olim, uap->rlp, sizeof(olim)); + return (error); +} +#endif /* COMPAT_43 */ + +#ifndef _SYS_SYSPROTO_H_ +struct __setrlimit_args { + u_int which; + struct rlimit *rlp; +}; +#endif +int +sys_setrlimit(struct thread *td, struct __setrlimit_args *uap) +{ + struct rlimit alim; + int error; + + if ((error = copyin(uap->rlp, &alim, sizeof(struct rlimit)))) + return (error); + error = kern_setrlimit(td, uap->which, &alim); + return (error); +} + +static void +lim_cb(void *arg) +{ + struct rlimit rlim; + struct thread *td; + struct proc *p; + + p = arg; + PROC_LOCK_ASSERT(p, MA_OWNED); + /* + * Check if the process exceeds its cpu resource allocation. If + * it reaches the max, arrange to kill the process in ast(). + */ + if (p->p_cpulimit == RLIM_INFINITY) + return; + PROC_STATLOCK(p); + FOREACH_THREAD_IN_PROC(p, td) { + ruxagg(p, td); + } + PROC_STATUNLOCK(p); + if (p->p_rux.rux_runtime > p->p_cpulimit * cpu_tickrate()) { + lim_rlimit_proc(p, RLIMIT_CPU, &rlim); + if (p->p_rux.rux_runtime >= rlim.rlim_max * cpu_tickrate()) { + killproc(p, "exceeded maximum CPU limit"); + } else { + if (p->p_cpulimit < rlim.rlim_max) + p->p_cpulimit += 5; + kern_psignal(p, SIGXCPU); + } + } + if ((p->p_flag & P_WEXIT) == 0) + callout_reset_sbt(&p->p_limco, SBT_1S, 0, + lim_cb, p, C_PREL(1)); +} + +int +kern_setrlimit(struct thread *td, u_int which, struct rlimit *limp) +{ + + return (kern_proc_setrlimit(td, td->td_proc, which, limp)); +} + +int +kern_proc_setrlimit(struct thread *td, struct proc *p, u_int which, + struct rlimit *limp) +{ + struct plimit *newlim, *oldlim; + struct rlimit *alimp; + struct rlimit oldssiz; + int error; + + if (which >= RLIM_NLIMITS) + return (EINVAL); + + /* + * Preserve historical bugs by treating negative limits as unsigned. + */ + if (limp->rlim_cur < 0) + limp->rlim_cur = RLIM_INFINITY; + if (limp->rlim_max < 0) + limp->rlim_max = RLIM_INFINITY; + + oldssiz.rlim_cur = 0; + newlim = lim_alloc(); + PROC_LOCK(p); + oldlim = p->p_limit; + alimp = &oldlim->pl_rlimit[which]; + if (limp->rlim_cur > alimp->rlim_max || + limp->rlim_max > alimp->rlim_max) + if ((error = priv_check(td, PRIV_PROC_SETRLIMIT))) { + PROC_UNLOCK(p); + lim_free(newlim); + return (error); + } + if (limp->rlim_cur > limp->rlim_max) + limp->rlim_cur = limp->rlim_max; + lim_copy(newlim, oldlim); + alimp = &newlim->pl_rlimit[which]; + + switch (which) { + + case RLIMIT_CPU: + if (limp->rlim_cur != RLIM_INFINITY && + p->p_cpulimit == RLIM_INFINITY) + callout_reset_sbt(&p->p_limco, SBT_1S, 0, + lim_cb, p, C_PREL(1)); + p->p_cpulimit = limp->rlim_cur; + break; + case RLIMIT_DATA: + if (limp->rlim_cur > maxdsiz) + limp->rlim_cur = maxdsiz; + if (limp->rlim_max > maxdsiz) + limp->rlim_max = maxdsiz; + break; + + case RLIMIT_STACK: + if (limp->rlim_cur > maxssiz) + limp->rlim_cur = maxssiz; + if (limp->rlim_max > maxssiz) + limp->rlim_max = maxssiz; + oldssiz = *alimp; + if (p->p_sysent->sv_fixlimit != NULL) + p->p_sysent->sv_fixlimit(&oldssiz, + RLIMIT_STACK); + break; + + case RLIMIT_NOFILE: + if (limp->rlim_cur > maxfilesperproc) + limp->rlim_cur = maxfilesperproc; + if (limp->rlim_max > maxfilesperproc) + limp->rlim_max = maxfilesperproc; + break; + + case RLIMIT_NPROC: + if (limp->rlim_cur > maxprocperuid) + limp->rlim_cur = maxprocperuid; + if (limp->rlim_max > maxprocperuid) + limp->rlim_max = maxprocperuid; + if (limp->rlim_cur < 1) + limp->rlim_cur = 1; + if (limp->rlim_max < 1) + limp->rlim_max = 1; + break; + } + if (p->p_sysent->sv_fixlimit != NULL) + p->p_sysent->sv_fixlimit(limp, which); + *alimp = *limp; + p->p_limit = newlim; + PROC_UPDATE_COW(p); + PROC_UNLOCK(p); + lim_free(oldlim); + + if (which == RLIMIT_STACK && + /* + * Skip calls from exec_new_vmspace(), done when stack is + * not mapped yet. + */ + (td != curthread || (p->p_flag & P_INEXEC) == 0)) { + /* + * Stack is allocated to the max at exec time with only + * "rlim_cur" bytes accessible. If stack limit is going + * up make more accessible, if going down make inaccessible. + */ + if (limp->rlim_cur != oldssiz.rlim_cur) { + vm_offset_t addr; + vm_size_t size; + vm_prot_t prot; + + if (limp->rlim_cur > oldssiz.rlim_cur) { + prot = p->p_sysent->sv_stackprot; + size = limp->rlim_cur - oldssiz.rlim_cur; + addr = p->p_sysent->sv_usrstack - + limp->rlim_cur; + } else { + prot = VM_PROT_NONE; + size = oldssiz.rlim_cur - limp->rlim_cur; + addr = p->p_sysent->sv_usrstack - + oldssiz.rlim_cur; + } + addr = trunc_page(addr); + size = round_page(size); + (void)vm_map_protect(&p->p_vmspace->vm_map, + addr, addr + size, prot, FALSE); + } + } + + return (0); +} + +#ifndef _SYS_SYSPROTO_H_ +struct __getrlimit_args { + u_int which; + struct rlimit *rlp; +}; +#endif +/* ARGSUSED */ +int +sys_getrlimit(struct thread *td, struct __getrlimit_args *uap) +{ + struct rlimit rlim; + int error; + + if (uap->which >= RLIM_NLIMITS) + return (EINVAL); + lim_rlimit(td, uap->which, &rlim); + error = copyout(&rlim, uap->rlp, sizeof(struct rlimit)); + return (error); +} + +/* + * Transform the running time and tick information for children of proc p + * into user and system time usage. + */ +void +calccru(struct proc *p, struct timeval *up, struct timeval *sp) +{ + + PROC_LOCK_ASSERT(p, MA_OWNED); + calcru1(p, &p->p_crux, up, sp); +} + +/* + * Transform the running time and tick information in proc p into user + * and system time usage. If appropriate, include the current time slice + * on this CPU. + */ +void +calcru(struct proc *p, struct timeval *up, struct timeval *sp) +{ + struct thread *td; + uint64_t runtime, u; + + PROC_LOCK_ASSERT(p, MA_OWNED); + PROC_STATLOCK_ASSERT(p, MA_OWNED); + /* + * If we are getting stats for the current process, then add in the + * stats that this thread has accumulated in its current time slice. + * We reset the thread and CPU state as if we had performed a context + * switch right here. + */ + td = curthread; + if (td->td_proc == p) { + u = cpu_ticks(); + runtime = u - PCPU_GET(switchtime); + td->td_runtime += runtime; + td->td_incruntime += runtime; + PCPU_SET(switchtime, u); + } + /* Make sure the per-thread stats are current. */ + FOREACH_THREAD_IN_PROC(p, td) { + if (td->td_incruntime == 0) + continue; + ruxagg(p, td); + } + calcru1(p, &p->p_rux, up, sp); +} + +/* Collect resource usage for a single thread. */ +void +rufetchtd(struct thread *td, struct rusage *ru) +{ + struct proc *p; + uint64_t runtime, u; + + p = td->td_proc; + PROC_STATLOCK_ASSERT(p, MA_OWNED); + THREAD_LOCK_ASSERT(td, MA_OWNED); + /* + * If we are getting stats for the current thread, then add in the + * stats that this thread has accumulated in its current time slice. + * We reset the thread and CPU state as if we had performed a context + * switch right here. + */ + if (td == curthread) { + u = cpu_ticks(); + runtime = u - PCPU_GET(switchtime); + td->td_runtime += runtime; + td->td_incruntime += runtime; + PCPU_SET(switchtime, u); + } + ruxagg(p, td); + *ru = td->td_ru; + calcru1(p, &td->td_rux, &ru->ru_utime, &ru->ru_stime); +} + +/* XXX: the MI version is too slow to use: */ +#ifndef __HAVE_INLINE_FLSLL +#define flsll(x) (fls((x) >> 32) != 0 ? fls((x) >> 32) + 32 : fls(x)) +#endif + +static uint64_t +mul64_by_fraction(uint64_t a, uint64_t b, uint64_t c) +{ + uint64_t acc, bh, bl; + int i, s, sa, sb; + + /* + * Calculate (a * b) / c accurately enough without overflowing. c + * must be nonzero, and its top bit must be 0. a or b must be + * <= c, and the implementation is tuned for b <= c. + * + * The comments about times are for use in calcru1() with units of + * microseconds for 'a' and stathz ticks at 128 Hz for b and c. + * + * Let n be the number of top zero bits in c. Each iteration + * either returns, or reduces b by right shifting it by at least n. + * The number of iterations is at most 1 + 64 / n, and the error is + * at most the number of iterations. + * + * It is very unusual to need even 2 iterations. Previous + * implementations overflowed essentially by returning early in the + * first iteration, with n = 38 giving overflow at 105+ hours and + * n = 32 giving overlow at at 388+ days despite a more careful + * calculation. 388 days is a reasonable uptime, and the calculation + * needs to work for the uptime times the number of CPUs since 'a' + * is per-process. + */ + if (a >= (uint64_t)1 << 63) + return (0); /* Unsupported arg -- can't happen. */ + acc = 0; + for (i = 0; i < 128; i++) { + sa = flsll(a); + sb = flsll(b); + if (sa + sb <= 64) + /* Up to 105 hours on first iteration. */ + return (acc + (a * b) / c); + if (a >= c) { + /* + * This reduction is based on a = q * c + r, with the + * remainder r < c. 'a' may be large to start, and + * moving bits from b into 'a' at the end of the loop + * sets the top bit of 'a', so the reduction makes + * significant progress. + */ + acc += (a / c) * b; + a %= c; + sa = flsll(a); + if (sa + sb <= 64) + /* Up to 388 days on first iteration. */ + return (acc + (a * b) / c); + } + + /* + * This step writes a * b as a * ((bh << s) + bl) = + * a * (bh << s) + a * bl = (a << s) * bh + a * bl. The 2 + * additive terms are handled separately. Splitting in + * this way is linear except for rounding errors. + * + * s = 64 - sa is the maximum such that a << s fits in 64 + * bits. Since a < c and c has at least 1 zero top bit, + * sa < 64 and s > 0. Thus this step makes progress by + * reducing b (it increases 'a', but taking remainders on + * the next iteration completes the reduction). + * + * Finally, the choice for s is just what is needed to keep + * a * bl from overflowing, so we don't need complications + * like a recursive call mul64_by_fraction(a, bl, c) to + * handle the second additive term. + */ + s = 64 - sa; + bh = b >> s; + bl = b - (bh << s); + acc += (a * bl) / c; + a <<= s; + b = bh; + } + return (0); /* Algorithm failure -- can't happen. */ +} + +static void +calcru1(struct proc *p, struct rusage_ext *ruxp, struct timeval *up, + struct timeval *sp) +{ + /* {user, system, interrupt, total} {ticks, usec}: */ + uint64_t ut, uu, st, su, it, tt, tu; + + ut = ruxp->rux_uticks; + st = ruxp->rux_sticks; + it = ruxp->rux_iticks; + tt = ut + st + it; + if (tt == 0) { + /* Avoid divide by zero */ + st = 1; + tt = 1; + } + tu = cputick2usec(ruxp->rux_runtime); + if ((int64_t)tu < 0) { + /* XXX: this should be an assert /phk */ + printf("calcru: negative runtime of %jd usec for pid %d (%s)\n", + (intmax_t)tu, p->p_pid, p->p_comm); + tu = ruxp->rux_tu; + } + + /* Subdivide tu. Avoid overflow in the multiplications. */ + if (__predict_true(tu <= ((uint64_t)1 << 38) && tt <= (1 << 26))) { + /* Up to 76 hours when stathz is 128. */ + uu = (tu * ut) / tt; + su = (tu * st) / tt; + } else { + uu = mul64_by_fraction(tu, ut, tt); + su = mul64_by_fraction(tu, st, tt); + } + + if (tu >= ruxp->rux_tu) { + /* + * The normal case, time increased. + * Enforce monotonicity of bucketed numbers. + */ + if (uu < ruxp->rux_uu) + uu = ruxp->rux_uu; + if (su < ruxp->rux_su) + su = ruxp->rux_su; + } else if (tu + 3 > ruxp->rux_tu || 101 * tu > 100 * ruxp->rux_tu) { + /* + * When we calibrate the cputicker, it is not uncommon to + * see the presumably fixed frequency increase slightly over + * time as a result of thermal stabilization and NTP + * discipline (of the reference clock). We therefore ignore + * a bit of backwards slop because we expect to catch up + * shortly. We use a 3 microsecond limit to catch low + * counts and a 1% limit for high counts. + */ + uu = ruxp->rux_uu; + su = ruxp->rux_su; + tu = ruxp->rux_tu; + } else { /* tu < ruxp->rux_tu */ + /* + * What happened here was likely that a laptop, which ran at + * a reduced clock frequency at boot, kicked into high gear. + * The wisdom of spamming this message in that case is + * dubious, but it might also be indicative of something + * serious, so lets keep it and hope laptops can be made + * more truthful about their CPU speed via ACPI. + */ + printf("calcru: runtime went backwards from %ju usec " + "to %ju usec for pid %d (%s)\n", + (uintmax_t)ruxp->rux_tu, (uintmax_t)tu, + p->p_pid, p->p_comm); + } + + ruxp->rux_uu = uu; + ruxp->rux_su = su; + ruxp->rux_tu = tu; + + up->tv_sec = uu / 1000000; + up->tv_usec = uu % 1000000; + sp->tv_sec = su / 1000000; + sp->tv_usec = su % 1000000; +} + +#ifndef _SYS_SYSPROTO_H_ +struct getrusage_args { + int who; + struct rusage *rusage; +}; +#endif +int +sys_getrusage(struct thread *td, struct getrusage_args *uap) +{ + struct rusage ru; + int error; + + error = kern_getrusage(td, uap->who, &ru); + if (error == 0) + error = copyout(&ru, uap->rusage, sizeof(struct rusage)); + return (error); +} + +int +kern_getrusage(struct thread *td, int who, struct rusage *rup) +{ + struct proc *p; + int error; + + error = 0; + p = td->td_proc; + PROC_LOCK(p); + switch (who) { + case RUSAGE_SELF: + rufetchcalc(p, rup, &rup->ru_utime, + &rup->ru_stime); + break; + + case RUSAGE_CHILDREN: + *rup = p->p_stats->p_cru; + calccru(p, &rup->ru_utime, &rup->ru_stime); + break; + + case RUSAGE_THREAD: + PROC_STATLOCK(p); + thread_lock(td); + rufetchtd(td, rup); + thread_unlock(td); + PROC_STATUNLOCK(p); + break; + + default: + error = EINVAL; + } + PROC_UNLOCK(p); + return (error); +} + +void +rucollect(struct rusage *ru, struct rusage *ru2) +{ + long *ip, *ip2; + int i; + + if (ru->ru_maxrss < ru2->ru_maxrss) + ru->ru_maxrss = ru2->ru_maxrss; + ip = &ru->ru_first; + ip2 = &ru2->ru_first; + for (i = &ru->ru_last - &ru->ru_first; i >= 0; i--) + *ip++ += *ip2++; +} + +void +ruadd(struct rusage *ru, struct rusage_ext *rux, struct rusage *ru2, + struct rusage_ext *rux2) +{ + + rux->rux_runtime += rux2->rux_runtime; + rux->rux_uticks += rux2->rux_uticks; + rux->rux_sticks += rux2->rux_sticks; + rux->rux_iticks += rux2->rux_iticks; + rux->rux_uu += rux2->rux_uu; + rux->rux_su += rux2->rux_su; + rux->rux_tu += rux2->rux_tu; + rucollect(ru, ru2); +} + +/* + * Aggregate tick counts into the proc's rusage_ext. + */ +static void +ruxagg_locked(struct rusage_ext *rux, struct thread *td) +{ + + THREAD_LOCK_ASSERT(td, MA_OWNED); + PROC_STATLOCK_ASSERT(td->td_proc, MA_OWNED); + rux->rux_runtime += td->td_incruntime; + rux->rux_uticks += td->td_uticks; + rux->rux_sticks += td->td_sticks; + rux->rux_iticks += td->td_iticks; +} + +void +ruxagg(struct proc *p, struct thread *td) +{ + + thread_lock(td); + ruxagg_locked(&p->p_rux, td); + ruxagg_locked(&td->td_rux, td); + td->td_incruntime = 0; + td->td_uticks = 0; + td->td_iticks = 0; + td->td_sticks = 0; + thread_unlock(td); +} + +/* + * Update the rusage_ext structure and fetch a valid aggregate rusage + * for proc p if storage for one is supplied. + */ +void +rufetch(struct proc *p, struct rusage *ru) +{ + struct thread *td; + + PROC_STATLOCK_ASSERT(p, MA_OWNED); + + *ru = p->p_ru; + if (p->p_numthreads > 0) { + FOREACH_THREAD_IN_PROC(p, td) { + ruxagg(p, td); + rucollect(ru, &td->td_ru); + } + } +} + +/* + * Atomically perform a rufetch and a calcru together. + * Consumers, can safely assume the calcru is executed only once + * rufetch is completed. + */ +void +rufetchcalc(struct proc *p, struct rusage *ru, struct timeval *up, + struct timeval *sp) +{ + + PROC_STATLOCK(p); + rufetch(p, ru); + calcru(p, up, sp); + PROC_STATUNLOCK(p); +} + +/* + * Allocate a new resource limits structure and initialize its + * reference count and mutex pointer. + */ +struct plimit * +lim_alloc() +{ + struct plimit *limp; + + limp = malloc(sizeof(struct plimit), M_PLIMIT, M_WAITOK); + refcount_init(&limp->pl_refcnt, 1); + return (limp); +} + +struct plimit * +lim_hold(struct plimit *limp) +{ + + refcount_acquire(&limp->pl_refcnt); + return (limp); +} + +void +lim_fork(struct proc *p1, struct proc *p2) +{ + + PROC_LOCK_ASSERT(p1, MA_OWNED); + PROC_LOCK_ASSERT(p2, MA_OWNED); + + p2->p_limit = lim_hold(p1->p_limit); + callout_init_mtx(&p2->p_limco, &p2->p_mtx, 0); + if (p1->p_cpulimit != RLIM_INFINITY) + callout_reset_sbt(&p2->p_limco, SBT_1S, 0, + lim_cb, p2, C_PREL(1)); +} + +void +lim_free(struct plimit *limp) +{ + + if (refcount_release(&limp->pl_refcnt)) + free((void *)limp, M_PLIMIT); +} + +/* + * Make a copy of the plimit structure. + * We share these structures copy-on-write after fork. + */ +void +lim_copy(struct plimit *dst, struct plimit *src) +{ + + KASSERT(dst->pl_refcnt <= 1, ("lim_copy to shared limit")); + bcopy(src->pl_rlimit, dst->pl_rlimit, sizeof(src->pl_rlimit)); +} + +/* + * Return the hard limit for a particular system resource. The + * which parameter specifies the index into the rlimit array. + */ +rlim_t +lim_max(struct thread *td, int which) +{ + struct rlimit rl; + + lim_rlimit(td, which, &rl); + return (rl.rlim_max); +} + +rlim_t +lim_max_proc(struct proc *p, int which) +{ + struct rlimit rl; + + lim_rlimit_proc(p, which, &rl); + return (rl.rlim_max); +} + +/* + * Return the current (soft) limit for a particular system resource. + * The which parameter which specifies the index into the rlimit array + */ +rlim_t +lim_cur(struct thread *td, int which) +{ + struct rlimit rl; + + lim_rlimit(td, which, &rl); + return (rl.rlim_cur); +} + +rlim_t +lim_cur_proc(struct proc *p, int which) +{ + struct rlimit rl; + + lim_rlimit_proc(p, which, &rl); + return (rl.rlim_cur); +} + +/* + * Return a copy of the entire rlimit structure for the system limit + * specified by 'which' in the rlimit structure pointed to by 'rlp'. + */ +void +lim_rlimit(struct thread *td, int which, struct rlimit *rlp) +{ + struct proc *p = td->td_proc; + + MPASS(td == curthread); + KASSERT(which >= 0 && which < RLIM_NLIMITS, + ("request for invalid resource limit")); + *rlp = td->td_limit->pl_rlimit[which]; + if (p->p_sysent->sv_fixlimit != NULL) + p->p_sysent->sv_fixlimit(rlp, which); +} + +void +lim_rlimit_proc(struct proc *p, int which, struct rlimit *rlp) +{ + + PROC_LOCK_ASSERT(p, MA_OWNED); + KASSERT(which >= 0 && which < RLIM_NLIMITS, + ("request for invalid resource limit")); + *rlp = p->p_limit->pl_rlimit[which]; + if (p->p_sysent->sv_fixlimit != NULL) + p->p_sysent->sv_fixlimit(rlp, which); +} + +void +uihashinit() +{ + + uihashtbl = hashinit(maxproc / 16, M_UIDINFO, &uihash); + rw_init(&uihashtbl_lock, "uidinfo hash"); +} + +/* + * Look up a uidinfo struct for the parameter uid. + * uihashtbl_lock must be locked. + * Increase refcount on uidinfo struct returned. + */ +static struct uidinfo * +uilookup(uid_t uid) +{ + struct uihashhead *uipp; + struct uidinfo *uip; + + rw_assert(&uihashtbl_lock, RA_LOCKED); + uipp = UIHASH(uid); + LIST_FOREACH(uip, uipp, ui_hash) + if (uip->ui_uid == uid) { + uihold(uip); + break; + } + + return (uip); +} + +/* + * Find or allocate a struct uidinfo for a particular uid. + * Returns with uidinfo struct referenced. + * uifree() should be called on a struct uidinfo when released. + */ +struct uidinfo * +uifind(uid_t uid) +{ + struct uidinfo *new_uip, *uip; + struct ucred *cred; + + cred = curthread->td_ucred; + if (cred->cr_uidinfo->ui_uid == uid) { + uip = cred->cr_uidinfo; + uihold(uip); + return (uip); + } else if (cred->cr_ruidinfo->ui_uid == uid) { + uip = cred->cr_ruidinfo; + uihold(uip); + return (uip); + } + + rw_rlock(&uihashtbl_lock); + uip = uilookup(uid); + rw_runlock(&uihashtbl_lock); + if (uip != NULL) + return (uip); + + new_uip = malloc(sizeof(*new_uip), M_UIDINFO, M_WAITOK | M_ZERO); + racct_create(&new_uip->ui_racct); + refcount_init(&new_uip->ui_ref, 1); + new_uip->ui_uid = uid; + + rw_wlock(&uihashtbl_lock); + /* + * There's a chance someone created our uidinfo while we + * were in malloc and not holding the lock, so we have to + * make sure we don't insert a duplicate uidinfo. + */ + if ((uip = uilookup(uid)) == NULL) { + LIST_INSERT_HEAD(UIHASH(uid), new_uip, ui_hash); + rw_wunlock(&uihashtbl_lock); + uip = new_uip; + } else { + rw_wunlock(&uihashtbl_lock); + racct_destroy(&new_uip->ui_racct); + free(new_uip, M_UIDINFO); + } + return (uip); +} + +/* + * Place another refcount on a uidinfo struct. + */ +void +uihold(struct uidinfo *uip) +{ + + refcount_acquire(&uip->ui_ref); +} + +/*- + * Since uidinfo structs have a long lifetime, we use an + * opportunistic refcounting scheme to avoid locking the lookup hash + * for each release. + * + * If the refcount hits 0, we need to free the structure, + * which means we need to lock the hash. + * Optimal case: + * After locking the struct and lowering the refcount, if we find + * that we don't need to free, simply unlock and return. + * Suboptimal case: + * If refcount lowering results in need to free, bump the count + * back up, lose the lock and acquire the locks in the proper + * order to try again. + */ +void +uifree(struct uidinfo *uip) +{ + int old; + + /* Prepare for optimal case. */ + old = uip->ui_ref; + if (old > 1 && atomic_cmpset_int(&uip->ui_ref, old, old - 1)) + return; + + /* Prepare for suboptimal case. */ + rw_wlock(&uihashtbl_lock); + if (refcount_release(&uip->ui_ref) == 0) { + rw_wunlock(&uihashtbl_lock); + return; + } + + racct_destroy(&uip->ui_racct); + LIST_REMOVE(uip, ui_hash); + rw_wunlock(&uihashtbl_lock); + + if (uip->ui_sbsize != 0) + printf("freeing uidinfo: uid = %d, sbsize = %ld\n", + uip->ui_uid, uip->ui_sbsize); + if (uip->ui_proccnt != 0) + printf("freeing uidinfo: uid = %d, proccnt = %ld\n", + uip->ui_uid, uip->ui_proccnt); + if (uip->ui_vmsize != 0) + printf("freeing uidinfo: uid = %d, swapuse = %lld\n", + uip->ui_uid, (unsigned long long)uip->ui_vmsize); + free(uip, M_UIDINFO); +} + +#ifdef RACCT +void +ui_racct_foreach(void (*callback)(struct racct *racct, + void *arg2, void *arg3), void (*pre)(void), void (*post)(void), + void *arg2, void *arg3) +{ + struct uidinfo *uip; + struct uihashhead *uih; + + rw_rlock(&uihashtbl_lock); + if (pre != NULL) + (pre)(); + for (uih = &uihashtbl[uihash]; uih >= uihashtbl; uih--) { + LIST_FOREACH(uip, uih, ui_hash) { + (callback)(uip->ui_racct, arg2, arg3); + } + } + if (post != NULL) + (post)(); + rw_runlock(&uihashtbl_lock); +} +#endif + +static inline int +chglimit(struct uidinfo *uip, long *limit, int diff, rlim_t max, const char *name) +{ + long new; + + /* Don't allow them to exceed max, but allow subtraction. */ + new = atomic_fetchadd_long(limit, (long)diff) + diff; + if (diff > 0 && max != 0) { + if (new < 0 || new > max) { + atomic_subtract_long(limit, (long)diff); + return (0); + } + } else if (new < 0) + printf("negative %s for uid = %d\n", name, uip->ui_uid); + return (1); +} + +/* + * Change the count associated with number of processes + * a given user is using. When 'max' is 0, don't enforce a limit + */ +int +chgproccnt(struct uidinfo *uip, int diff, rlim_t max) +{ + + return (chglimit(uip, &uip->ui_proccnt, diff, max, "proccnt")); +} + +/* + * Change the total socket buffer size a user has used. + */ +int +chgsbsize(struct uidinfo *uip, u_int *hiwat, u_int to, rlim_t max) +{ + int diff, rv; + + diff = to - *hiwat; + if (diff > 0 && max == 0) { + rv = 0; + } else { + rv = chglimit(uip, &uip->ui_sbsize, diff, max, "sbsize"); + if (rv != 0) + *hiwat = to; + } + return (rv); +} + +/* + * Change the count associated with number of pseudo-terminals + * a given user is using. When 'max' is 0, don't enforce a limit + */ +int +chgptscnt(struct uidinfo *uip, int diff, rlim_t max) +{ + + return (chglimit(uip, &uip->ui_ptscnt, diff, max, "ptscnt")); +} + +int +chgkqcnt(struct uidinfo *uip, int diff, rlim_t max) +{ + + return (chglimit(uip, &uip->ui_kqcnt, diff, max, "kqcnt")); +} + +int +chgumtxcnt(struct uidinfo *uip, int diff, rlim_t max) +{ + + return (chglimit(uip, &uip->ui_umtxcnt, diff, max, "umtxcnt")); +} |