File: [local] / sys / kern / kern_exit.c (download)
Revision 1.1.1.1 (vendor branch), Tue Mar 4 16:14:53 2008 UTC (16 years, 4 months ago) by nbrk
Branch: OPENBSD_4_2_BASE, MAIN
CVS Tags: jornada-partial-support-wip, HEAD Changes since 1.1: +0 -0 lines
Import of OpenBSD 4.2 release kernel tree with initial code to support
Jornada 720/728, StrongARM 1110-based handheld PC.
At this point kernel roots on NFS and boots into vfs_mountroot() and traps.
What is supported:
- glass console, Jornada framebuffer (jfb) works in 16bpp direct color mode
(needs some palette tweaks for non black/white/blue colors, i think)
- saic, SA11x0 interrupt controller (needs cleanup)
- sacom, SA11x0 UART (supported only as boot console for now)
- SA11x0 GPIO controller fully supported (but can't handle multiple interrupt
handlers on one gpio pin)
- sassp, SSP port on SA11x0 that attaches spibus
- Jornada microcontroller (jmcu) to control kbd, battery, etc throught
the SPI bus (wskbd attaches on jmcu, but not tested)
- tod functions seem work
- initial code for SA-1111 (chip companion) : this is TODO
Next important steps, i think:
- gpio and intc on sa1111
- pcmcia support for sa11x0 (and sa1111 help logic)
- REAL root on nfs when we have PCMCIA support (we may use any of supported pccard NICs)
- root on wd0! (using already supported PCMCIA-ATA)
|
/* $OpenBSD: kern_exit.c,v 1.71 2007/04/12 22:14:15 tedu 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. 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/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 <sys/acct.h>
#include <sys/filedesc.h>
#include <sys/signalvar.h>
#include <sys/sched.h>
#include <sys/ktrace.h>
#include <sys/pool.h>
#include <sys/mutex.h>
#ifdef SYSVSHM
#include <sys/shm.h>
#endif
#ifdef SYSVSEM
#include <sys/sem.h>
#endif
#include "systrace.h"
#include <dev/systrace.h>
#include <sys/mount.h>
#include <sys/syscallargs.h>
#include <machine/cpu.h>
#include <uvm/uvm_extern.h>
/*
* exit --
* Death of process.
*/
int
sys_exit(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), EXIT_NORMAL);
/* NOTREACHED */
return (0);
}
#ifdef RTHREADS
int
sys_threxit(struct proc *p, void *v, register_t *retval)
{
struct sys_threxit_args *uap = v;
exit1(p, W_EXITCODE(SCARG(uap, rval), 0), EXIT_THREAD);
return (0);
}
#endif
/*
* 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(struct proc *p, int rv, int flags)
{
struct proc *q, *nq;
if (p->p_pid == 1)
panic("init died (signal %d, exit %d)",
WTERMSIG(rv), WEXITSTATUS(rv));
/* unlink ourselves from the active threads */
TAILQ_REMOVE(&p->p_p->ps_threads, p, p_thr_link);
#ifdef RTHREADS
if (TAILQ_EMPTY(&p->p_p->ps_threads))
wakeup(&p->p_p->ps_threads);
/*
* if one thread calls exit, we take down everybody.
* we have to be careful not to get recursively caught.
* this is kinda sick.
*/
if (flags == EXIT_NORMAL && p->p_p->ps_mainproc != p &&
(p->p_p->ps_mainproc->p_flag & P_WEXIT) == 0) {
/*
* we are one of the threads. we SIGKILL the parent,
* it will wake us up again, then we proceed.
*/
atomic_setbits_int(&p->p_p->ps_mainproc->p_flag, P_IGNEXITRV);
p->p_p->ps_mainproc->p_xstat = rv;
psignal(p->p_p->ps_mainproc, SIGKILL);
tsleep(p->p_p, PUSER, "thrdying", 0);
} else if (p == p->p_p->ps_mainproc) {
atomic_setbits_int(&p->p_flag, P_WEXIT);
if (flags == EXIT_NORMAL) {
q = TAILQ_FIRST(&p->p_p->ps_threads);
for (; q != NULL; q = nq) {
nq = TAILQ_NEXT(q, p_thr_link);
atomic_setbits_int(&q->p_flag, P_IGNEXITRV);
q->p_xstat = rv;
psignal(q, SIGKILL);
}
}
wakeup(p->p_p);
while (!TAILQ_EMPTY(&p->p_p->ps_threads))
tsleep(&p->p_p->ps_threads, PUSER, "thrdeath", 0);
}
#endif
if (p->p_flag & P_PROFIL)
stopprofclock(p);
p->p_ru = pool_get(&rusage_pool, PR_WAITOK);
/*
* If parent is waiting for us to exit or exec, P_PPWAIT is set; we
* wake up the parent early to avoid deadlock.
*/
atomic_setbits_int(&p->p_flag, P_WEXIT);
atomic_clearbits_int(&p->p_flag, P_TRACED);
if (p->p_flag & P_PPWAIT) {
atomic_clearbits_int(&p->p_flag, P_PPWAIT);
wakeup(p->p_pptr);
}
p->p_sigignore = ~0;
p->p_siglist = 0;
timeout_del(&p->p_realit_to);
timeout_del(&p->p_stats->p_virt_to);
timeout_del(&p->p_stats->p_prof_to);
/*
* Close open files and release open-file table.
* This may block!
*/
fdfree(p);
#ifdef SYSVSEM
semexit(p);
#endif
if (SESS_LEADER(p)) {
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);
#ifdef ACCOUNTING
(void)acct_process(p);
#endif
#ifdef KTRACE
/*
* release trace file
*/
p->p_traceflag = 0; /* don't trace the vrele() */
if (p->p_tracep)
ktrsettracevnode(p, NULL);
#endif
#if NSYSTRACE > 0
if (ISSET(p->p_flag, P_SYSTRACE))
systrace_exit(p);
#endif
/*
* NOTE: WE ARE NO LONGER ALLOWED TO SLEEP!
*/
p->p_stat = SDEAD;
/*
* Remove proc from pidhash chain so looking it up won't
* work. Move it from allproc to zombproc, but do not yet
* wake up the reaper. We will put the proc on the
* deadproc list later (using the p_hash member), and
* wake up the reaper when we do.
*/
LIST_REMOVE(p, p_hash);
LIST_REMOVE(p, p_list);
LIST_INSERT_HEAD(&zombproc, p, p_list);
/*
* Give orphaned children to init(8).
*/
q = LIST_FIRST(&p->p_children);
if (q) /* only need this if any child is S_ZOMB */
wakeup(initproc);
for (; q != 0; q = nq) {
nq = LIST_NEXT(q, p_sibling);
proc_reparent(q, initproc);
/*
* Traced processes are killed
* since their existence means someone is screwing up.
*/
if (q->p_flag & P_TRACED) {
atomic_clearbits_int(&q->p_flag, P_TRACED);
psignal(q, SIGKILL);
}
}
/*
* Save exit status and final rusage info, adding in child rusage
* info and self times.
*/
if (!(p->p_flag & P_IGNEXITRV))
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 interested parties of our demise.
*/
KNOTE(&p->p_klist, NOTE_EXIT);
/*
* 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 (LIST_EMPTY(&pp->p_children))
wakeup(pp);
}
if (p->p_exitsig != 0)
psignal(p->p_pptr, P_EXITSIG(p));
wakeup(p->p_pptr);
/*
* Release the process's signal state.
*/
sigactsfree(p);
/*
* 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 emulation has process exit hook, call it now.
*/
if (p->p_emul->e_proc_exit)
(*p->p_emul->e_proc_exit)(p);
/* This process no longer needs to hold the kernel lock. */
KERNEL_PROC_UNLOCK(p);
/*
* Finally, call machine-dependent code to switch to a new
* context (possibly the idle context). Once we are no longer
* using the dead process's vmspace and stack, exit2() will be
* called to schedule those resources to be released by the
* reaper thread.
*
* Note that cpu_exit() will end with a call equivalent to
* cpu_switch(), finishing our execution (pun intended).
*/
uvmexp.swtch++;
cpu_exit(p);
}
/*
* Locking of this proclist is special; it's accessed in a
* critical section of process exit, and thus locking it can't
* modify interrupt state. We use a simple spin lock for this
* proclist. Processes on this proclist are also on zombproc;
* we use the p_hash member to linkup to deadproc.
*/
struct mutex deadproc_mutex = MUTEX_INITIALIZER(IPL_NONE);
struct proclist deadproc = LIST_HEAD_INITIALIZER(deadproc);
/*
* We are called from cpu_exit() once it is safe to schedule the
* dead process's resources to be freed.
*
* NOTE: One must be careful with locking in this routine. It's
* called from a critical section in machine-dependent code, so
* we should refrain from changing any interrupt state.
*
* We lock the deadproc list, place the proc on that list (using
* the p_hash member), and wake up the reaper.
*/
void
exit2(struct proc *p)
{
int s;
mtx_enter(&deadproc_mutex);
LIST_INSERT_HEAD(&deadproc, p, p_hash);
mtx_leave(&deadproc_mutex);
wakeup(&deadproc);
SCHED_LOCK(s);
}
/*
* Process reaper. This is run by a kernel thread to free the resources
* of a dead process. Once the resources are free, the process becomes
* a zombie, and the parent is allowed to read the undead's status.
*/
void
reaper(void)
{
struct proc *p;
KERNEL_PROC_UNLOCK(curproc);
for (;;) {
mtx_enter(&deadproc_mutex);
p = LIST_FIRST(&deadproc);
if (p == NULL) {
/* No work for us; go to sleep until someone exits. */
mtx_leave(&deadproc_mutex);
(void) tsleep(&deadproc, PVM, "reaper", 0);
continue;
}
/* Remove us from the deadproc list. */
LIST_REMOVE(p, p_hash);
mtx_leave(&deadproc_mutex);
KERNEL_PROC_LOCK(curproc);
/*
* Give machine-dependent code a chance to free any
* resources it couldn't free while still running on
* that process's context. This must be done before
* uvm_exit(), in case these resources are in the PCB.
*/
cpu_wait(p);
/*
* Free the VM resources we're still holding on to.
* We must do this from a valid thread because doing
* so may block.
*/
uvm_exit(p);
/* Process is now a true zombie. */
if ((p->p_flag & P_NOZOMBIE) == 0) {
p->p_stat = SZOMB;
/* Wake up the parent so it can get exit status. */
psignal(p->p_pptr, SIGCHLD);
wakeup(p->p_pptr);
} else {
/* Noone will wait for us. Just zap the process now */
proc_zap(p);
}
KERNEL_PROC_UNLOCK(curproc);
}
}
pid_t
sys_wait4(struct proc *q, void *v, register_t *retval)
{
struct sys_wait4_args /* {
syscallarg(pid_t) pid;
syscallarg(int *) status;
syscallarg(int) options;
syscallarg(struct rusage *) rusage;
} */ *uap = v;
int nfound;
struct proc *p, *t;
int status, error;
if (SCARG(uap, pid) == 0)
SCARG(uap, pid) = -q->p_pgid;
if (SCARG(uap, options) &~ (WUNTRACED|WNOHANG|WALTSIG|WCONTINUED))
return (EINVAL);
loop:
nfound = 0;
LIST_FOREACH(p, &q->p_children, p_sibling) {
if ((p->p_flag & P_NOZOMBIE) ||
(SCARG(uap, pid) != WAIT_ANY &&
p->p_pid != SCARG(uap, pid) &&
p->p_pgid != -SCARG(uap, pid)))
continue;
/*
* Wait for processes with p_exitsig != SIGCHLD processes only
* if WALTSIG is set; wait for processes with pexitsig ==
* SIGCHLD only if WALTSIG is clear.
*/
if ((SCARG(uap, options) & WALTSIG) ?
(p->p_exitsig == SIGCHLD) : (P_EXITSIG(p) != SIGCHLD))
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(&status,
SCARG(uap, status), sizeof(status));
if (error)
return (error);
}
if (SCARG(uap, rusage) &&
(error = copyout(p->p_ru,
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);
if (p->p_exitsig != 0)
psignal(t, P_EXITSIG(p));
wakeup(t);
return (0);
}
scheduler_wait_hook(q, p);
p->p_xstat = 0;
ruadd(&q->p_stats->p_cru, p->p_ru);
proc_zap(p);
return (0);
}
if (p->p_stat == SSTOP && (p->p_flag & P_WAITED) == 0 &&
(p->p_flag & P_TRACED || SCARG(uap, options) & WUNTRACED)) {
atomic_setbits_int(&p->p_flag, P_WAITED);
retval[0] = p->p_pid;
if (SCARG(uap, status)) {
status = W_STOPCODE(p->p_xstat);
error = copyout(&status, SCARG(uap, status),
sizeof(status));
} else
error = 0;
return (error);
}
if ((SCARG(uap, options) & WCONTINUED) && (p->p_flag & P_CONTINUED)) {
atomic_clearbits_int(&p->p_flag, P_CONTINUED);
retval[0] = p->p_pid;
if (SCARG(uap, status)) {
status = _WCONTINUED;
error = copyout(&status, 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(q, PWAIT | PCATCH, "wait", 0)) != 0)
return (error);
goto loop;
}
/*
* make process 'parent' the new parent of process 'child'.
*/
void
proc_reparent(struct proc *child, struct proc *parent)
{
if (child->p_pptr == parent)
return;
if (parent == initproc)
child->p_exitsig = SIGCHLD;
LIST_REMOVE(child, p_sibling);
LIST_INSERT_HEAD(&parent->p_children, child, p_sibling);
child->p_pptr = parent;
}
void
proc_zap(struct proc *p)
{
pool_put(&rusage_pool, p->p_ru);
if (p->p_ptstat)
free(p->p_ptstat, M_SUBPROC);
/*
* 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);
/*
* Release reference to text vnode
*/
if (p->p_textvp)
vrele(p->p_textvp);
/*
* Remove us from our process list, possibly killing the process
* in the process (pun intended).
*/
#if 0
TAILQ_REMOVE(&p->p_p->ps_threads, p, p_thr_link);
#endif
if (TAILQ_EMPTY(&p->p_p->ps_threads)) {
limfree(p->p_p->ps_limit);
if (--p->p_p->ps_cred->p_refcnt == 0) {
crfree(p->p_p->ps_cred->pc_ucred);
pool_put(&pcred_pool, p->p_p->ps_cred);
}
pool_put(&process_pool, p->p_p);
}
pool_put(&proc_pool, p);
nprocs--;
}