diff options
Diffstat (limited to 'sys/kern/kern_exit.c')
| -rw-r--r-- | sys/kern/kern_exit.c | 492 |
1 files changed, 492 insertions, 0 deletions
diff --git a/sys/kern/kern_exit.c b/sys/kern/kern_exit.c new file mode 100644 index 0000000..03353c7 --- /dev/null +++ b/sys/kern/kern_exit.c @@ -0,0 +1,492 @@ +/* + * 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 <sys/param.h> +#include <sys/systm.h> +#include <sys/map.h> +#include <sys/ioctl.h> +#include <sys/proc.h> +#include <sys/tty.h> +#include <sys/time.h> +#include <sys/resource.h> +#include <sys/kernel.h> +#include <sys/buf.h> +#include <sys/wait.h> +#include <sys/file.h> +#include <sys/vnode.h> +#include <sys/syslog.h> +#include <sys/malloc.h> +#include <sys/resourcevar.h> +#include <sys/ptrace.h> + +#include <machine/cpu.h> +#ifdef COMPAT_43 +#include <machine/reg.h> +#include <machine/psl.h> +#endif + +#include <vm/vm.h> +#include <vm/vm_kern.h> + +__dead void cpu_exit __P((struct proc *)); +__dead void exit1 __P((struct proc *, int)); + +/* + * exit -- + * Death of process. + */ +struct rexit_args { + int rval; +}; +__dead void +exit(p, uap, retval) + struct proc *p; + struct rexit_args *uap; + int *retval; +{ + + exit1(p, W_EXITCODE(uap->rval, 0)); + /* NOTREACHED */ +} + +/* + * 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. + */ +__dead void +exit1(p, rv) + register struct proc *p; + int rv; +{ + register struct proc *q, *nq; + register struct proc **pp; + 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 will wakeup the parent below. + */ + p->p_flag &= ~(P_TRACED | P_PPWAIT); + p->p_flag |= P_WEXIT; + 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 two chunks should probably be moved to vmspace_exit. */ + vm = p->p_vmspace; +#ifdef SYSVSHM + if (vm->vm_shm) + shmexit(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 (vm->vm_refcnt == 1) + (void) vm_map_remove(&vm->vm_map, VM_MIN_ADDRESS, + VM_MAXUSER_ADDRESS); + + 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) + vgoneall(sp->s_ttyvp); + } + 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. + */ + if (*p->p_prev = p->p_next) + p->p_next->p_prev = p->p_prev; + if (p->p_next = zombproc) + p->p_next->p_prev = &p->p_next; + p->p_prev = &zombproc; + zombproc = p; + p->p_stat = SZOMB; + + for (pp = &pidhash[PIDHASH(p->p_pid)]; *pp; pp = &(*pp)->p_hash) + if (*pp == p) { + *pp = p->p_hash; + goto done; + } + panic("exit"); +done: + + if (p->p_cptr) /* only need this if any child is S_ZOMB */ + wakeup((caddr_t) initproc); + for (q = p->p_cptr; q != NULL; q = nq) { + nq = q->p_osptr; + if (nq != NULL) + nq->p_ysptr = NULL; + if (initproc->p_cptr) + initproc->p_cptr->p_ysptr = q; + q->p_osptr = initproc->p_cptr; + q->p_ysptr = NULL; + initproc->p_cptr = q; + + q->p_pptr = 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); + } + } + p->p_cptr = NULL; + + /* + * 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); + + /* + * Notify parent that we're gone. + */ + psignal(p->p_pptr, SIGCHLD); + wakeup((caddr_t)p->p_pptr); +#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); +} + +struct wait_args { + int pid; + int *status; + int options; + struct rusage *rusage; +#ifdef COMPAT_43 + int compat; /* pseudo */ +#endif +}; + +#ifdef COMPAT_43 +#if defined(hp300) || defined(luna68k) +#include <machine/frame.h> +#define GETPS(rp) ((struct frame *)(rp))->f_sr +#else +#define GETPS(rp) (rp)[PS] +#endif + +owait(p, uap, retval) + struct proc *p; + register struct wait_args *uap; + int *retval; +{ + +#ifdef PSL_ALLCC + if ((GETPS(p->p_md.md_regs) & PSL_ALLCC) != PSL_ALLCC) { + uap->options = 0; + uap->rusage = NULL; + } else { + uap->options = p->p_md.md_regs[R0]; + uap->rusage = (struct rusage *)p->p_md.md_regs[R1]; + } +#else + uap->options = 0; + uap->rusage = NULL; +#endif + uap->pid = WAIT_ANY; + uap->status = NULL; + uap->compat = 1; + return (wait1(p, uap, retval)); +} + +wait4(p, uap, retval) + struct proc *p; + struct wait_args *uap; + int *retval; +{ + + uap->compat = 0; + return (wait1(p, uap, retval)); +} +#else +#define wait1 wait4 +#endif + +int +wait1(q, uap, retval) + register struct proc *q; + register struct wait_args *uap; + int retval[]; +{ + register int nfound; + register struct proc *p, *t; + int status, error; + + if (uap->pid == 0) + uap->pid = -q->p_pgid; +#ifdef notyet + if (uap->options &~ (WUNTRACED|WNOHANG)) + return (EINVAL); +#endif +loop: + nfound = 0; + for (p = q->p_cptr; p; p = p->p_osptr) { + if (uap->pid != WAIT_ANY && + p->p_pid != uap->pid && p->p_pgid != -uap->pid) + continue; + nfound++; + if (p->p_stat == SZOMB) { + retval[0] = p->p_pid; +#ifdef COMPAT_43 + if (uap->compat) + retval[1] = p->p_xstat; + else +#endif + if (uap->status) { + status = p->p_xstat; /* convert to int */ + if (error = copyout((caddr_t)&status, + (caddr_t)uap->status, sizeof(status))) + return (error); + } + if (uap->rusage && (error = copyout((caddr_t)p->p_ru, + (caddr_t)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); + } + p->p_xstat = 0; + ruadd(&q->p_stats->p_cru, p->p_ru); + FREE(p->p_ru, M_ZOMBIE); + + /* + * 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); + + /* + * Finally finished with old proc entry. + * Unlink it from its process group and free it. + */ + leavepgrp(p); + if (*p->p_prev = p->p_next) /* off zombproc */ + p->p_next->p_prev = p->p_prev; + if (q = p->p_ysptr) + q->p_osptr = p->p_osptr; + if (q = p->p_osptr) + q->p_ysptr = p->p_ysptr; + if ((q = p->p_pptr)->p_cptr == p) + q->p_cptr = p->p_osptr; + + /* + * 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 || uap->options & WUNTRACED)) { + p->p_flag |= P_WAITED; + retval[0] = p->p_pid; +#ifdef COMPAT_43 + if (uap->compat) { + retval[1] = W_STOPCODE(p->p_xstat); + error = 0; + } else +#endif + if (uap->status) { + status = W_STOPCODE(p->p_xstat); + error = copyout((caddr_t)&status, + (caddr_t)uap->status, sizeof(status)); + } else + error = 0; + return (error); + } + } + if (nfound == 0) + return (ECHILD); + if (uap->options & WNOHANG) { + retval[0] = 0; + return (0); + } + if (error = tsleep((caddr_t)q, PWAIT | PCATCH, "wait", 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; +{ + register struct proc *o; + register struct proc *y; + + if (child->p_pptr == parent) + return; + + /* fix up the child linkage for the old parent */ + o = child->p_osptr; + y = child->p_ysptr; + if (y) + y->p_osptr = o; + if (o) + o->p_ysptr = y; + if (child->p_pptr->p_cptr == child) + child->p_pptr->p_cptr = o; + + /* fix up child linkage for new parent */ + o = parent->p_cptr; + if (o) + o->p_ysptr = child; + child->p_osptr = o; + child->p_ysptr = NULL; + parent->p_cptr = child; + child->p_pptr = parent; +} |
