/* $OpenBSD: kern_exit.c,v 1.17 1999/03/12 17:49:37 deraadt Exp $ */ /* $NetBSD: kern_exit.c,v 1.39 1996/04/22 01:38:25 christos Exp $ */ /* * Copyright (c) 1982, 1986, 1989, 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. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. 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_exit.c 8.7 (Berkeley) 2/12/94 */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef SYSVSHM #include #endif #ifdef SYSVSEM #include #endif #include #include #include #include #include #if defined(UVM) #include #endif /* * exit -- * Death of process. */ int sys_exit(p, v, retval) struct proc *p; void *v; register_t *retval; { struct sys_exit_args /* { syscallarg(int) rval; } */ *uap = v; exit1(p, W_EXITCODE(SCARG(uap, rval), 0)); /* NOTREACHED */ return (0); } /* * Exit: deallocate address space and other resources, change proc state * to zombie, and unlink proc from allproc and parent's lists. Save exit * status and rusage for wait(). Check for child processes and orphan them. */ void exit1(p, rv) register struct proc *p; int rv; { register struct proc *q, *nq; register struct vmspace *vm; if (p->p_pid == 1) panic("init died (signal %d, exit %d)", WTERMSIG(rv), WEXITSTATUS(rv)); #ifdef PGINPROF vmsizmon(); #endif if (p->p_flag & P_PROFIL) stopprofclock(p); MALLOC(p->p_ru, struct rusage *, sizeof(struct rusage), M_ZOMBIE, M_WAITOK); /* * If parent is waiting for us to exit or exec, P_PPWAIT is set; we * wake up the parent early to avoid deadlock. */ p->p_flag |= P_WEXIT; p->p_flag &= ~P_TRACED; if (p->p_flag & P_PPWAIT) { p->p_flag &= ~P_PPWAIT; wakeup((caddr_t)p->p_pptr); } p->p_sigignore = ~0; p->p_siglist = 0; untimeout(realitexpire, (caddr_t)p); /* * Close open files and release open-file table. * This may block! */ fdfree(p); /* The next three chunks should probably be moved to vmspace_exit. */ vm = p->p_vmspace; #ifdef SYSVSHM if (vm->vm_shm) shmexit(p); #endif #ifdef SYSVSEM semexit(p); #endif /* * Release user portion of address space. * This releases references to vnodes, * which could cause I/O if the file has been unlinked. * Need to do this early enough that we can still sleep. * Can't free the entire vmspace as the kernel stack * may be mapped within that space also. */ #if defined(UVM) if (vm->vm_refcnt == 1) (void) uvm_deallocate(&vm->vm_map, VM_MIN_ADDRESS, VM_MAXUSER_ADDRESS - VM_MIN_ADDRESS); #else if (vm->vm_refcnt == 1) (void) vm_map_remove(&vm->vm_map, VM_MIN_ADDRESS, VM_MAXUSER_ADDRESS); #endif if (SESS_LEADER(p)) { register struct session *sp = p->p_session; if (sp->s_ttyvp) { /* * Controlling process. * Signal foreground pgrp, * drain controlling terminal * and revoke access to controlling terminal. */ if (sp->s_ttyp->t_session == sp) { if (sp->s_ttyp->t_pgrp) pgsignal(sp->s_ttyp->t_pgrp, SIGHUP, 1); (void) ttywait(sp->s_ttyp); /* * The tty could have been revoked * if we blocked. */ if (sp->s_ttyvp) VOP_REVOKE(sp->s_ttyvp, REVOKEALL); } if (sp->s_ttyvp) vrele(sp->s_ttyvp); sp->s_ttyvp = NULL; /* * s_ttyp is not zero'd; we use this to indicate * that the session once had a controlling terminal. * (for logging and informational purposes) */ } sp->s_leader = NULL; } fixjobc(p, p->p_pgrp, 0); p->p_rlimit[RLIMIT_FSIZE].rlim_cur = RLIM_INFINITY; (void)acct_process(p); #ifdef KTRACE /* * release trace file */ p->p_traceflag = 0; /* don't trace the vrele() */ if (p->p_tracep) vrele(p->p_tracep); #endif /* * Remove proc from allproc queue and pidhash chain. * Place onto zombproc. Unlink from parent's child list. */ LIST_REMOVE(p, p_list); LIST_INSERT_HEAD(&zombproc, p, p_list); p->p_stat = SZOMB; LIST_REMOVE(p, p_hash); q = p->p_children.lh_first; if (q) /* only need this if any child is S_ZOMB */ wakeup((caddr_t)initproc); for (; q != 0; q = nq) { nq = q->p_sibling.le_next; proc_reparent(q, initproc); /* * Traced processes are killed * since their existence means someone is screwing up. */ if (q->p_flag & P_TRACED) { q->p_flag &= ~P_TRACED; psignal(q, SIGKILL); } } /* * Save exit status and final rusage info, adding in child rusage * info and self times. */ p->p_xstat = rv; *p->p_ru = p->p_stats->p_ru; calcru(p, &p->p_ru->ru_utime, &p->p_ru->ru_stime, NULL); ruadd(p->p_ru, &p->p_stats->p_cru); /* * clear %cpu usage during swap */ p->p_pctcpu = 0; /* * Notify parent that we're gone. If we have P_NOZOMBIE or parent has * the P_NOCLDWAIT flag set, notify process 1 instead (and hope it * will handle this situation). */ if ((p->p_flag & P_NOZOMBIE) || (p->p_pptr->p_flag & P_NOCLDWAIT)) { struct proc *pp = p->p_pptr; proc_reparent(p, initproc); /* * If this was the last child of our parent, notify * parent, so in case he was wait(2)ing, he will * continue. */ if (pp->p_children.lh_first == NULL) wakeup((caddr_t)pp); } psignal(p->p_pptr, SIGCHLD); wakeup((caddr_t)p->p_pptr); /* * Notify procfs debugger */ if (p->p_flag & P_FSTRACE) wakeup((caddr_t)p); #if defined(tahoe) /* move this to cpu_exit */ p->p_addr->u_pcb.pcb_savacc.faddr = (float *)NULL; #endif /* * Clear curproc after we've done all operations * that could block, and before tearing down the rest * of the process state that might be used from clock, etc. * Also, can't clear curproc while we're still runnable, * as we're not on a run queue (we are current, just not * a proper proc any longer!). * * Other substructures are freed from wait(). */ curproc = NULL; if (--p->p_limit->p_refcnt == 0) FREE(p->p_limit, M_SUBPROC); /* * Finally, call machine-dependent code to release the remaining * resources including address space, the kernel stack and pcb. * The address space is released by "vmspace_free(p->p_vmspace)"; * This is machine-dependent, as we may have to change stacks * or ensure that the current one isn't reallocated before we * finish. cpu_exit will end with a call to cpu_swtch(), finishing * our execution (pun intended). */ cpu_exit(p); } int sys_wait4(q, v, retval) register struct proc *q; void *v; register_t *retval; { register struct sys_wait4_args /* { syscallarg(int) pid; syscallarg(int *) status; syscallarg(int) options; syscallarg(struct rusage *) rusage; } */ *uap = v; register int nfound; register struct proc *p, *t; int status, error; #ifdef COMPAT_09 SCARG(uap, pid) = (short)SCARG(uap, pid); #endif if (SCARG(uap, pid) == 0) SCARG(uap, pid) = -q->p_pgid; if (SCARG(uap, options) &~ (WUNTRACED|WNOHANG)) return (EINVAL); loop: nfound = 0; for (p = q->p_children.lh_first; p != 0; p = p->p_sibling.le_next) { if ((p->p_flag & P_NOZOMBIE) || (SCARG(uap, pid) != WAIT_ANY && p->p_pid != SCARG(uap, pid) && p->p_pgid != -SCARG(uap, pid))) continue; nfound++; if (p->p_stat == SZOMB) { retval[0] = p->p_pid; if (SCARG(uap, status)) { status = p->p_xstat; /* convert to int */ error = copyout((caddr_t)&status, (caddr_t)SCARG(uap, status), sizeof(status)); if (error) return (error); } if (SCARG(uap, rusage) && (error = copyout((caddr_t)p->p_ru, (caddr_t)SCARG(uap, rusage), sizeof (struct rusage)))) return (error); /* * If we got the child via a ptrace 'attach', * we need to give it back to the old parent. */ if (p->p_oppid && (t = pfind(p->p_oppid))) { p->p_oppid = 0; proc_reparent(p, t); psignal(t, SIGCHLD); wakeup((caddr_t)t); return (0); } /* Charge us for our child's sins */ curproc->p_estcpu = min(curproc->p_estcpu + p->p_estcpu, UCHAR_MAX); p->p_xstat = 0; ruadd(&q->p_stats->p_cru, p->p_ru); FREE(p->p_ru, M_ZOMBIE); /* * Finally finished with old proc entry. * Unlink it from its process group and free it. */ leavepgrp(p); LIST_REMOVE(p, p_list); /* off zombproc */ LIST_REMOVE(p, p_sibling); /* * Decrement the count of procs running with this uid. */ (void)chgproccnt(p->p_cred->p_ruid, -1); /* * Free up credentials. */ if (--p->p_cred->p_refcnt == 0) { crfree(p->p_cred->pc_ucred); FREE(p->p_cred, M_SUBPROC); } /* * Release reference to text vnode */ if (p->p_textvp) vrele(p->p_textvp); /* * Give machine-dependent layer a chance * to free anything that cpu_exit couldn't * release while still running in process context. */ cpu_wait(p); FREE(p, M_PROC); nprocs--; return (0); } if (p->p_stat == SSTOP && (p->p_flag & P_WAITED) == 0 && (p->p_flag & P_TRACED || SCARG(uap, options) & WUNTRACED)) { p->p_flag |= P_WAITED; retval[0] = p->p_pid; if (SCARG(uap, status)) { status = W_STOPCODE(p->p_xstat); error = copyout((caddr_t)&status, (caddr_t)SCARG(uap, status), sizeof(status)); } else error = 0; return (error); } } if (nfound == 0) return (ECHILD); if (SCARG(uap, options) & WNOHANG) { retval[0] = 0; return (0); } if ((error = tsleep((caddr_t)q, PWAIT | PCATCH, "wait", 0)) != 0) return (error); goto loop; } /* * make process 'parent' the new parent of process 'child'. */ void proc_reparent(child, parent) register struct proc *child; register struct proc *parent; { if (child->p_pptr == parent) return; LIST_REMOVE(child, p_sibling); LIST_INSERT_HEAD(&parent->p_children, child, p_sibling); child->p_pptr = parent; }