1 /*- 2 * Copyright (c) 1982, 1986, 1989, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)kern_exit.c 8.7 (Berkeley) 2/12/94 39 * $Id: kern_exit.c,v 1.13 1994/12/28 06:15:07 davidg Exp $ 40 */ 41 42 #include <sys/param.h> 43 #include <sys/systm.h> 44 #include <sys/sysent.h> 45 #include <sys/ioctl.h> 46 #include <sys/proc.h> 47 #include <sys/tty.h> 48 #include <sys/time.h> 49 #include <sys/resource.h> 50 #include <sys/kernel.h> 51 #include <sys/buf.h> 52 #include <sys/wait.h> 53 #include <sys/file.h> 54 #include <sys/vnode.h> 55 #include <sys/syslog.h> 56 #include <sys/malloc.h> 57 #include <sys/resourcevar.h> 58 #include <sys/signalvar.h> 59 #include <sys/ptrace.h> 60 #include <sys/shm.h> 61 #include <sys/filedesc.h> 62 63 #include <machine/cpu.h> 64 #ifdef COMPAT_43 65 #include <machine/reg.h> 66 #include <machine/psl.h> 67 #endif 68 69 #include <vm/vm.h> 70 #include <vm/vm_kern.h> 71 72 /* 73 * exit -- 74 * Death of process. 75 */ 76 struct rexit_args { 77 int rval; 78 }; 79 __dead void 80 exit(p, uap, retval) 81 struct proc *p; 82 struct rexit_args *uap; 83 int *retval; 84 { 85 86 exit1(p, W_EXITCODE(uap->rval, 0)); 87 /* NOTREACHED */ 88 while (1); 89 } 90 91 /* 92 * Exit: deallocate address space and other resources, change proc state 93 * to zombie, and unlink proc from allproc and parent's lists. Save exit 94 * status and rusage for wait(). Check for child processes and orphan them. 95 */ 96 __dead void 97 exit1(p, rv) 98 register struct proc *p; 99 int rv; 100 { 101 register struct proc *q, *nq; 102 register struct proc **pp; 103 register struct vmspace *vm; 104 105 if (p->p_pid == 1) { 106 printf("init died (signal %d, exit %d)\n", 107 WTERMSIG(rv), WEXITSTATUS(rv)); 108 panic("Going nowhere without my init!"); 109 } 110 #ifdef PGINPROF 111 vmsizmon(); 112 #endif 113 if (p->p_flag & P_PROFIL) 114 stopprofclock(p); 115 MALLOC(p->p_ru, struct rusage *, sizeof(struct rusage), 116 M_ZOMBIE, M_WAITOK); 117 /* 118 * If parent is waiting for us to exit or exec, 119 * P_PPWAIT is set; we will wakeup the parent below. 120 */ 121 p->p_flag &= ~(P_TRACED | P_PPWAIT); 122 p->p_flag |= P_WEXIT; 123 p->p_sigignore = ~0; 124 p->p_siglist = 0; 125 untimeout(realitexpire, (caddr_t)p); 126 127 /* 128 * Close open files and release open-file table. 129 * This may block! 130 */ 131 fdfree(p); 132 133 /* The next two chunks should probably be moved to vmspace_exit. */ 134 vm = p->p_vmspace; 135 #ifdef SYSVSHM 136 if (vm->vm_shm) 137 shmexit(p); 138 #endif 139 /* 140 * Release user portion of address space. 141 * This releases references to vnodes, 142 * which could cause I/O if the file has been unlinked. 143 * Need to do this early enough that we can still sleep. 144 * Can't free the entire vmspace as the kernel stack 145 * may be mapped within that space also. 146 */ 147 if (vm->vm_refcnt == 1) 148 (void) vm_map_remove(&vm->vm_map, VM_MIN_ADDRESS, 149 VM_MAXUSER_ADDRESS); 150 151 if (SESS_LEADER(p)) { 152 register struct session *sp = p->p_session; 153 154 if (sp->s_ttyvp) { 155 /* 156 * Controlling process. 157 * Signal foreground pgrp, 158 * drain controlling terminal 159 * and revoke access to controlling terminal. 160 */ 161 if (sp->s_ttyp->t_session == sp) { 162 if (sp->s_ttyp->t_pgrp) 163 pgsignal(sp->s_ttyp->t_pgrp, SIGHUP, 1); 164 (void) ttywait(sp->s_ttyp); 165 /* 166 * The tty could have been revoked 167 * if we blocked. 168 */ 169 if (sp->s_ttyvp) 170 vgoneall(sp->s_ttyvp); 171 } 172 if (sp->s_ttyvp) 173 vrele(sp->s_ttyvp); 174 sp->s_ttyvp = NULL; 175 /* 176 * s_ttyp is not zero'd; we use this to indicate 177 * that the session once had a controlling terminal. 178 * (for logging and informational purposes) 179 */ 180 } 181 sp->s_leader = NULL; 182 } 183 fixjobc(p, p->p_pgrp, 0); 184 p->p_rlimit[RLIMIT_FSIZE].rlim_cur = RLIM_INFINITY; 185 (void)acct_process(p); 186 #ifdef KTRACE 187 /* 188 * release trace file 189 */ 190 p->p_traceflag = 0; /* don't trace the vrele() */ 191 if (p->p_tracep) 192 vrele(p->p_tracep); 193 #endif 194 /* 195 * Remove proc from allproc queue and pidhash chain. 196 * Place onto zombproc. Unlink from parent's child list. 197 */ 198 if ((*p->p_prev = p->p_next)) 199 p->p_next->p_prev = p->p_prev; 200 if ((p->p_next = zombproc)) 201 p->p_next->p_prev = &p->p_next; 202 p->p_prev = &zombproc; 203 zombproc = p; 204 p->p_stat = SZOMB; 205 206 for (pp = &pidhash[PIDHASH(p->p_pid)]; *pp; pp = &(*pp)->p_hash) 207 if (*pp == p) { 208 *pp = p->p_hash; 209 goto done; 210 } 211 panic("exit"); 212 done: 213 214 if (p->p_cptr) /* only need this if any child is S_ZOMB */ 215 wakeup((caddr_t) initproc); 216 for (q = p->p_cptr; q != NULL; q = nq) { 217 nq = q->p_osptr; 218 if (nq != NULL) 219 nq->p_ysptr = NULL; 220 if (initproc->p_cptr) 221 initproc->p_cptr->p_ysptr = q; 222 q->p_osptr = initproc->p_cptr; 223 q->p_ysptr = NULL; 224 initproc->p_cptr = q; 225 226 q->p_pptr = initproc; 227 /* 228 * Traced processes are killed 229 * since their existence means someone is screwing up. 230 */ 231 if (q->p_flag & P_TRACED) { 232 q->p_flag &= ~P_TRACED; 233 psignal(q, SIGKILL); 234 } 235 } 236 p->p_cptr = NULL; 237 238 /* 239 * Save exit status and final rusage info, adding in child rusage 240 * info and self times. 241 */ 242 p->p_xstat = rv; 243 *p->p_ru = p->p_stats->p_ru; 244 calcru(p, &p->p_ru->ru_utime, &p->p_ru->ru_stime, NULL); 245 ruadd(p->p_ru, &p->p_stats->p_cru); 246 247 /* 248 * Notify parent that we're gone. 249 */ 250 psignal(p->p_pptr, SIGCHLD); 251 wakeup((caddr_t)p->p_pptr); 252 #if defined(tahoe) 253 /* move this to cpu_exit */ 254 p->p_addr->u_pcb.pcb_savacc.faddr = (float *)NULL; 255 #endif 256 /* 257 * Clear curproc after we've done all operations 258 * that could block, and before tearing down the rest 259 * of the process state that might be used from clock, etc. 260 * Also, can't clear curproc while we're still runnable, 261 * as we're not on a run queue (we are current, just not 262 * a proper proc any longer!). 263 * 264 * Other substructures are freed from wait(). 265 */ 266 curproc = NULL; 267 if (--p->p_limit->p_refcnt == 0) { 268 FREE(p->p_limit, M_SUBPROC); 269 p->p_limit = NULL; 270 } 271 272 /* 273 * Finally, call machine-dependent code to release the remaining 274 * resources including address space, the kernel stack and pcb. 275 * The address space is released by "vmspace_free(p->p_vmspace)"; 276 * This is machine-dependent, as we may have to change stacks 277 * or ensure that the current one isn't reallocated before we 278 * finish. cpu_exit will end with a call to cpu_swtch(), finishing 279 * our execution (pun intended). 280 */ 281 cpu_exit(p); 282 } 283 284 #if defined(COMPAT_43) || defined(COMPAT_IBCS2) 285 #if defined(hp300) || defined(luna68k) 286 #include <machine/frame.h> 287 #define GETPS(rp) ((struct frame *)(rp))->f_sr 288 #else 289 #define GETPS(rp) (rp)[PS] 290 #endif 291 292 int 293 owait(p, uap, retval) 294 struct proc *p; 295 register struct wait_args *uap; 296 int *retval; 297 { 298 299 #ifdef PSL_ALLCC 300 if ((GETPS(p->p_md.md_regs) & PSL_ALLCC) != PSL_ALLCC) { 301 uap->options = 0; 302 uap->rusage = NULL; 303 } else { 304 uap->options = p->p_md.md_regs[R0]; 305 uap->rusage = (struct rusage *)p->p_md.md_regs[R1]; 306 } 307 #else 308 uap->options = 0; 309 uap->rusage = NULL; 310 #endif 311 uap->pid = WAIT_ANY; 312 uap->status = NULL; 313 uap->compat = 1; 314 return (wait1(p, uap, retval)); 315 } 316 317 int 318 wait4(p, uap, retval) 319 struct proc *p; 320 struct wait_args *uap; 321 int *retval; 322 { 323 324 uap->compat = 0; 325 return (wait1(p, uap, retval)); 326 } 327 #else 328 #define wait1 wait4 329 #endif 330 331 int 332 wait1(q, uap, retval) 333 register struct proc *q; 334 register struct wait_args *uap; 335 int retval[]; 336 { 337 register int nfound; 338 register struct proc *p, *t; 339 int status, error, sig; 340 341 if (uap->pid == 0) 342 uap->pid = -q->p_pgid; 343 #ifdef notyet 344 if (uap->options &~ (WUNTRACED|WNOHANG)) 345 return (EINVAL); 346 #endif 347 loop: 348 nfound = 0; 349 for (p = q->p_cptr; p; p = p->p_osptr) { 350 if (uap->pid != WAIT_ANY && 351 p->p_pid != uap->pid && p->p_pgid != -uap->pid) 352 continue; 353 nfound++; 354 #if defined(COMPAT_43) || defined(COMPAT_IBCS2) 355 if (q->p_sysent->sv_sigtbl) { 356 if ((p->p_xstat & 0xff) < q->p_sysent->sv_sigsize) 357 sig = q->p_sysent->sv_sigtbl[p->p_xstat & 0xff]; 358 else 359 sig = q->p_sysent->sv_sigsize + 1; 360 } else 361 sig = p->p_xstat; 362 #endif 363 if (p->p_stat == SZOMB) { 364 /* charge childs scheduling cpu usage to parent */ 365 if (curproc->p_pid != 1) { 366 curproc->p_estcpu = min(curproc->p_estcpu + 367 p->p_estcpu, UCHAR_MAX); 368 } 369 370 retval[0] = p->p_pid; 371 #if defined(COMPAT_43) || defined(COMPAT_IBCS2) 372 if (uap->compat) 373 retval[1] = sig; 374 else 375 #endif 376 if (uap->status) { 377 status = p->p_xstat; /* convert to int */ 378 if ((error = copyout((caddr_t)&status, 379 (caddr_t)uap->status, sizeof(status)))) 380 return (error); 381 } 382 if (uap->rusage && (error = copyout((caddr_t)p->p_ru, 383 (caddr_t)uap->rusage, sizeof (struct rusage)))) 384 return (error); 385 /* 386 * If we got the child via a ptrace 'attach', 387 * we need to give it back to the old parent. 388 */ 389 if (p->p_oppid && (t = pfind(p->p_oppid))) { 390 p->p_oppid = 0; 391 proc_reparent(p, t); 392 psignal(t, SIGCHLD); 393 wakeup((caddr_t)t); 394 return (0); 395 } 396 p->p_xstat = 0; 397 ruadd(&q->p_stats->p_cru, p->p_ru); 398 FREE(p->p_ru, M_ZOMBIE); 399 p->p_ru = NULL; 400 401 /* 402 * Decrement the count of procs running with this uid. 403 */ 404 (void)chgproccnt(p->p_cred->p_ruid, -1); 405 406 /* 407 * Free up credentials. 408 */ 409 if (--p->p_cred->p_refcnt == 0) { 410 crfree(p->p_cred->pc_ucred); 411 FREE(p->p_cred, M_SUBPROC); 412 p->p_cred = NULL; 413 } 414 415 /* 416 * Release reference to text vnode 417 */ 418 if (p->p_textvp) 419 vrele(p->p_textvp); 420 421 /* 422 * Finally finished with old proc entry. 423 * Unlink it from its process group and free it. 424 */ 425 leavepgrp(p); 426 if ((*p->p_prev = p->p_next)) /* off zombproc */ 427 p->p_next->p_prev = p->p_prev; 428 if ((q = p->p_ysptr)) 429 q->p_osptr = p->p_osptr; 430 if ((q = p->p_osptr)) 431 q->p_ysptr = p->p_ysptr; 432 if ((q = p->p_pptr)->p_cptr == p) 433 q->p_cptr = p->p_osptr; 434 435 /* 436 * Give machine-dependent layer a chance 437 * to free anything that cpu_exit couldn't 438 * release while still running in process context. 439 */ 440 cpu_wait(p); 441 FREE(p, M_PROC); 442 nprocs--; 443 return (0); 444 } 445 if (p->p_stat == SSTOP && (p->p_flag & P_WAITED) == 0 && 446 (p->p_flag & P_TRACED || uap->options & WUNTRACED)) { 447 p->p_flag |= P_WAITED; 448 retval[0] = p->p_pid; 449 #if defined(COMPAT_43) || defined(COMPAT_IBCS2) 450 if (uap->compat) { 451 retval[1] = W_STOPCODE(sig); 452 error = 0; 453 } else 454 #endif 455 if (uap->status) { 456 status = W_STOPCODE(p->p_xstat); 457 error = copyout((caddr_t)&status, 458 (caddr_t)uap->status, sizeof(status)); 459 } else 460 error = 0; 461 return (error); 462 } 463 } 464 if (nfound == 0) 465 return (ECHILD); 466 if (uap->options & WNOHANG) { 467 retval[0] = 0; 468 return (0); 469 } 470 if ((error = tsleep((caddr_t)q, PWAIT | PCATCH, "wait", 0))) 471 return (error); 472 goto loop; 473 } 474 475 /* 476 * make process 'parent' the new parent of process 'child'. 477 */ 478 void 479 proc_reparent(child, parent) 480 register struct proc *child; 481 register struct proc *parent; 482 { 483 register struct proc *o; 484 register struct proc *y; 485 486 if (child->p_pptr == parent) 487 return; 488 489 /* fix up the child linkage for the old parent */ 490 o = child->p_osptr; 491 y = child->p_ysptr; 492 if (y) 493 y->p_osptr = o; 494 if (o) 495 o->p_ysptr = y; 496 if (child->p_pptr->p_cptr == child) 497 child->p_pptr->p_cptr = o; 498 499 /* fix up child linkage for new parent */ 500 o = parent->p_cptr; 501 if (o) 502 o->p_ysptr = child; 503 child->p_osptr = o; 504 child->p_ysptr = NULL; 505 parent->p_cptr = child; 506 child->p_pptr = parent; 507 } 508