Rename printf -> kprintf in sys/ and add some defines where necessary
[dragonfly.git] / sys / kern / kern_fork.c
CommitLineData
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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_fork.c 8.6 (Berkeley) 4/8/94
5bc7cd8d 39 * $FreeBSD: src/sys/kern/kern_fork.c,v 1.72.2.14 2003/06/26 04:15:10 silby Exp $
4a22e893 40 * $DragonFly: src/sys/kern/kern_fork.c,v 1.59 2006/10/20 17:02:16 dillon Exp $
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41 */
42
43#include "opt_ktrace.h"
44
45#include <sys/param.h>
46#include <sys/systm.h>
47#include <sys/sysproto.h>
48#include <sys/filedesc.h>
49#include <sys/kernel.h>
50#include <sys/sysctl.h>
51#include <sys/malloc.h>
52#include <sys/proc.h>
53#include <sys/resourcevar.h>
54#include <sys/vnode.h>
55#include <sys/acct.h>
56#include <sys/ktrace.h>
dfc1fc13
EN
57#include <sys/unistd.h>
58#include <sys/jail.h>
59#include <sys/caps.h>
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60
61#include <vm/vm.h>
62#include <sys/lock.h>
63#include <vm/pmap.h>
64#include <vm/vm_map.h>
65#include <vm/vm_extern.h>
66#include <vm/vm_zone.h>
67
68#include <sys/vmmeter.h>
69#include <sys/user.h>
e43a034f 70#include <sys/thread2.h>
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71
72static MALLOC_DEFINE(M_ATFORK, "atfork", "atfork callback");
73
74/*
75 * These are the stuctures used to create a callout list for things to do
76 * when forking a process
77 */
78struct forklist {
79 forklist_fn function;
80 TAILQ_ENTRY(forklist) next;
81};
82
83TAILQ_HEAD(forklist_head, forklist);
84static struct forklist_head fork_list = TAILQ_HEAD_INITIALIZER(fork_list);
85
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86int forksleep; /* Place for fork1() to sleep on. */
87
88/* ARGSUSED */
89int
753fd850 90sys_fork(struct fork_args *uap)
984263bc 91{
553ea3c8 92 struct lwp *lp = curthread->td_lwp;
984263bc 93 struct proc *p2;
41c20dac 94 int error;
984263bc 95
167e6ecb 96 error = fork1(lp, RFFDG | RFPROC | RFPGLOCK, &p2);
984263bc 97 if (error == 0) {
553ea3c8 98 start_forked_proc(lp, p2);
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99 uap->sysmsg_fds[0] = p2->p_pid;
100 uap->sysmsg_fds[1] = 0;
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101 }
102 return error;
103}
104
105/* ARGSUSED */
106int
753fd850 107sys_vfork(struct vfork_args *uap)
984263bc 108{
553ea3c8 109 struct lwp *lp = curthread->td_lwp;
984263bc 110 struct proc *p2;
41c20dac 111 int error;
984263bc 112
167e6ecb 113 error = fork1(lp, RFFDG | RFPROC | RFPPWAIT | RFMEM | RFPGLOCK, &p2);
984263bc 114 if (error == 0) {
553ea3c8 115 start_forked_proc(lp, p2);
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116 uap->sysmsg_fds[0] = p2->p_pid;
117 uap->sysmsg_fds[1] = 0;
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118 }
119 return error;
120}
121
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122/*
123 * Handle rforks. An rfork may (1) operate on the current process without
124 * creating a new, (2) create a new process that shared the current process's
125 * vmspace, signals, and/or descriptors, or (3) create a new process that does
126 * not share these things (normal fork).
127 *
128 * Note that we only call start_forked_proc() if a new process is actually
129 * created.
130 *
131 * rfork { int flags }
132 */
984263bc 133int
753fd850 134sys_rfork(struct rfork_args *uap)
984263bc 135{
553ea3c8 136 struct lwp *lp = curthread->td_lwp;
984263bc 137 struct proc *p2;
41c20dac 138 int error;
984263bc 139
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140 if ((uap->flags & RFKERNELONLY) != 0)
141 return (EINVAL);
142
167e6ecb 143 error = fork1(lp, uap->flags | RFPGLOCK, &p2);
984263bc 144 if (error == 0) {
f61c1ff1 145 if (p2)
553ea3c8 146 start_forked_proc(lp, p2);
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147 uap->sysmsg_fds[0] = p2 ? p2->p_pid : 0;
148 uap->sysmsg_fds[1] = 0;
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149 }
150 return error;
151}
152
153
154int nprocs = 1; /* process 0 */
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155
156int
553ea3c8 157fork1(struct lwp *lp1, int flags, struct proc **procp)
984263bc 158{
553ea3c8 159 struct proc *p1 = lp1->lwp_proc;
984263bc 160 struct proc *p2, *pptr;
167e6ecb 161 struct pgrp *pgrp;
553ea3c8 162 struct lwp *lp2;
984263bc 163 uid_t uid;
167e6ecb 164 int ok, error;
51e64ff2 165 static int curfail = 0;
5bc7cd8d 166 static struct timeval lastfail;
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167 struct forklist *ep;
168 struct filedesc_to_leader *fdtol;
169
170 if ((flags & (RFFDG|RFCFDG)) == (RFFDG|RFCFDG))
171 return (EINVAL);
172
173 /*
174 * Here we don't create a new process, but we divorce
175 * certain parts of a process from itself.
176 */
177 if ((flags & RFPROC) == 0) {
178
bb3cd951 179 vm_fork(lp1, 0, flags);
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180
181 /*
182 * Close all file descriptors.
183 */
184 if (flags & RFCFDG) {
185 struct filedesc *fdtmp;
186 fdtmp = fdinit(p1);
187 fdfree(p1);
188 p1->p_fd = fdtmp;
189 }
190
191 /*
192 * Unshare file descriptors (from parent.)
193 */
194 if (flags & RFFDG) {
195 if (p1->p_fd->fd_refcnt > 1) {
196 struct filedesc *newfd;
197 newfd = fdcopy(p1);
198 fdfree(p1);
199 p1->p_fd = newfd;
200 }
201 }
202 *procp = NULL;
203 return (0);
204 }
205
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206 /*
207 * Interlock against process group signal delivery. If signals
208 * are pending after the interlock is obtained we have to restart
209 * the system call to process the signals. If we don't the child
210 * can miss a pgsignal (such as ^C) sent during the fork.
211 *
212 * We can't use CURSIG() here because it will process any STOPs
213 * and cause the process group lock to be held indefinitely. If
214 * a STOP occurs, the fork will be restarted after the CONT.
215 */
216 error = 0;
217 pgrp = NULL;
218 if ((flags & RFPGLOCK) && (pgrp = p1->p_pgrp) != NULL) {
219 lockmgr(&pgrp->pg_lock, LK_SHARED);
220 if (CURSIGNB(p1)) {
221 error = ERESTART;
222 goto done;
223 }
224 }
225
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226 /*
227 * Although process entries are dynamically created, we still keep
228 * a global limit on the maximum number we will create. Don't allow
229 * a nonprivileged user to use the last ten processes; don't let root
230 * exceed the limit. The variable nprocs is the current number of
231 * processes, maxproc is the limit.
232 */
41c20dac 233 uid = p1->p_ucred->cr_ruid;
984263bc 234 if ((nprocs >= maxproc - 10 && uid != 0) || nprocs >= maxproc) {
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235 if (ppsratecheck(&lastfail, &curfail, 1))
236 printf("maxproc limit exceeded by uid %d, please "
237 "see tuning(7) and login.conf(5).\n", uid);
377d4740 238 tsleep(&forksleep, 0, "fork", hz / 2);
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239 error = EAGAIN;
240 goto done;
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241 }
242 /*
243 * Increment the nprocs resource before blocking can occur. There
244 * are hard-limits as to the number of processes that can run.
245 */
246 nprocs++;
247
248 /*
249 * Increment the count of procs running with this uid. Don't allow
250 * a nonprivileged user to exceed their current limit.
251 */
41c20dac 252 ok = chgproccnt(p1->p_ucred->cr_ruidinfo, 1,
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253 (uid != 0) ? p1->p_rlimit[RLIMIT_NPROC].rlim_cur : 0);
254 if (!ok) {
255 /*
256 * Back out the process count
257 */
258 nprocs--;
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259 if (ppsratecheck(&lastfail, &curfail, 1))
260 printf("maxproc limit exceeded by uid %d, please "
261 "see tuning(7) and login.conf(5).\n", uid);
377d4740 262 tsleep(&forksleep, 0, "fork", hz / 2);
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263 error = EAGAIN;
264 goto done;
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265 }
266
267 /* Allocate new proc. */
51e64ff2 268 p2 = zalloc(proc_zone);
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269
270 /*
ef09c3ed 271 * Setup linkage for kernel based threading XXX lwp
984263bc 272 */
cb74210d 273 if (flags & RFTHREAD) {
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274 p2->p_peers = p1->p_peers;
275 p1->p_peers = p2;
276 p2->p_leader = p1->p_leader;
984263bc 277 } else {
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278 p2->p_peers = NULL;
279 p2->p_leader = p2;
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280 }
281
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282 p2->p_wakeup = 0;
283 p2->p_vmspace = NULL;
284 p2->p_numposixlocks = 0;
285 p2->p_emuldata = NULL;
51e64ff2 286 LIST_INIT(&p2->p_lwps);
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287
288 /* XXX lwp */
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289 lp2 = &p2->p_lwp;
290 lp2->lwp_proc = p2;
553ea3c8 291 lp2->lwp_tid = 0;
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292 LIST_INSERT_HEAD(&p2->p_lwps, lp2, lwp_list);
293 p2->p_nthreads = 1;
294 p2->p_nstopped = 0;
295 p2->p_lasttid = 0;
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296
297 /*
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298 * Setting the state to SIDL protects the partially initialized
299 * process once it starts getting hooked into the rest of the system.
984263bc 300 */
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301 p2->p_stat = SIDL;
302 proc_add_allproc(p2);
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303
304 /*
305 * Make a proc table entry for the new process.
306 * Start by zeroing the section of proc that is zero-initialized,
307 * then copy the section that is copied directly from the parent.
308 */
309 bzero(&p2->p_startzero,
310 (unsigned) ((caddr_t)&p2->p_endzero - (caddr_t)&p2->p_startzero));
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311 bzero(&lp2->lwp_startzero,
312 (unsigned) ((caddr_t)&lp2->lwp_endzero -
313 (caddr_t)&lp2->lwp_startzero));
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314 bcopy(&p1->p_startcopy, &p2->p_startcopy,
315 (unsigned) ((caddr_t)&p2->p_endcopy - (caddr_t)&p2->p_startcopy));
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316 bcopy(&p1->p_lwp.lwp_startcopy, &lp2->lwp_startcopy,
317 (unsigned) ((caddr_t)&lp2->lwp_endcopy -
318 (caddr_t)&lp2->lwp_startcopy));
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319
320 p2->p_aioinfo = NULL;
321
322 /*
323 * Duplicate sub-structures as needed.
324 * Increase reference counts on shared objects.
325 * The p_stats and p_sigacts substructs are set in vm_fork.
3a72e617 326 * p_lock is in the copy area and must be cleared.
984263bc 327 */
344ad853 328 p2->p_flag = 0;
3a72e617 329 p2->p_lock = 0;
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330 if (p1->p_flag & P_PROFIL)
331 startprofclock(p2);
dadab5e9 332 p2->p_ucred = crhold(p1->p_ucred);
984263bc 333
b40e316c 334 if (jailed(p2->p_ucred))
984263bc 335 p2->p_flag |= P_JAILED;
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336
337 if (p2->p_args)
338 p2->p_args->ar_ref++;
339
340 if (flags & RFSIGSHARE) {
341 p2->p_procsig = p1->p_procsig;
342 p2->p_procsig->ps_refcnt++;
343 if (p1->p_sigacts == &p1->p_addr->u_sigacts) {
344 struct sigacts *newsigacts;
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345
346 /* Create the shared sigacts structure */
347 MALLOC(newsigacts, struct sigacts *,
348 sizeof(struct sigacts), M_SUBPROC, M_WAITOK);
e43a034f 349 crit_enter();
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350 /*
351 * Set p_sigacts to the new shared structure.
352 * Note that this is updating p1->p_sigacts at the
353 * same time, since p_sigacts is just a pointer to
354 * the shared p_procsig->ps_sigacts.
355 */
356 p2->p_sigacts = newsigacts;
357 bcopy(&p1->p_addr->u_sigacts, p2->p_sigacts,
358 sizeof(*p2->p_sigacts));
359 *p2->p_sigacts = p1->p_addr->u_sigacts;
e43a034f 360 crit_exit();
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361 }
362 } else {
363 MALLOC(p2->p_procsig, struct procsig *, sizeof(struct procsig),
364 M_SUBPROC, M_WAITOK);
365 bcopy(p1->p_procsig, p2->p_procsig, sizeof(*p2->p_procsig));
366 p2->p_procsig->ps_refcnt = 1;
367 p2->p_sigacts = NULL; /* finished in vm_fork() */
368 }
369 if (flags & RFLINUXTHPN)
370 p2->p_sigparent = SIGUSR1;
371 else
372 p2->p_sigparent = SIGCHLD;
373
374 /* bump references to the text vnode (for procfs) */
375 p2->p_textvp = p1->p_textvp;
376 if (p2->p_textvp)
597aea93 377 vref(p2->p_textvp);
984263bc 378
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379 /*
380 * Handle file descriptors
381 */
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382 if (flags & RFCFDG) {
383 p2->p_fd = fdinit(p1);
384 fdtol = NULL;
385 } else if (flags & RFFDG) {
386 p2->p_fd = fdcopy(p1);
387 fdtol = NULL;
388 } else {
389 p2->p_fd = fdshare(p1);
390 if (p1->p_fdtol == NULL)
391 p1->p_fdtol =
392 filedesc_to_leader_alloc(NULL,
393 p1->p_leader);
394 if ((flags & RFTHREAD) != 0) {
395 /*
396 * Shared file descriptor table and
397 * shared process leaders.
398 */
399 fdtol = p1->p_fdtol;
400 fdtol->fdl_refcount++;
401 } else {
402 /*
403 * Shared file descriptor table, and
404 * different process leaders
405 */
98a7f915 406 fdtol = filedesc_to_leader_alloc(p1->p_fdtol, p2);
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407 }
408 }
409 p2->p_fdtol = fdtol;
c0b8a06d 410 p2->p_limit = plimit_fork(p1->p_limit);
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411
412 /*
413 * Preserve some more flags in subprocess. P_PROFIL has already
414 * been preserved.
415 */
416 p2->p_flag |= p1->p_flag & (P_SUGID | P_ALTSTACK);
417 if (p1->p_session->s_ttyvp != NULL && p1->p_flag & P_CONTROLT)
418 p2->p_flag |= P_CONTROLT;
419 if (flags & RFPPWAIT)
420 p2->p_flag |= P_PPWAIT;
421
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422 /*
423 * Inherit the virtual kernel structure (allows a virtual kernel
424 * to fork to simulate multiple cpus).
425 */
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426 p2->p_vkernel = NULL;
427 if (p1->p_vkernel)
428 vkernel_inherit(p1, p2);
0daa37a5 429
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430 /*
431 * Once we are on a pglist we may receive signals. XXX we might
432 * race a ^C being sent to the process group by not receiving it
433 * at all prior to this line.
434 */
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435 LIST_INSERT_AFTER(p1, p2, p_pglist);
436
437 /*
438 * Attach the new process to its parent.
439 *
440 * If RFNOWAIT is set, the newly created process becomes a child
441 * of init. This effectively disassociates the child from the
442 * parent.
443 */
444 if (flags & RFNOWAIT)
445 pptr = initproc;
446 else
447 pptr = p1;
448 p2->p_pptr = pptr;
449 LIST_INSERT_HEAD(&pptr->p_children, p2, p_sibling);
450 LIST_INIT(&p2->p_children);
98a7f915 451 varsymset_init(&p2->p_varsymset, &p1->p_varsymset);
8fbf9130 452 callout_init(&p2->p_ithandle);
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453
454#ifdef KTRACE
455 /*
456 * Copy traceflag and tracefile if enabled. If not inherited,
457 * these were zeroed above but we still could have a trace race
29f58392 458 * so make sure p2's p_tracenode is NULL.
984263bc 459 */
29f58392 460 if ((p1->p_traceflag & KTRFAC_INHERIT) && p2->p_tracenode == NULL) {
984263bc 461 p2->p_traceflag = p1->p_traceflag;
29f58392 462 p2->p_tracenode = ktrinherit(p1->p_tracenode);
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463 }
464#endif
465
466 /*
352f5709 467 * Inherit the scheduler and initialize scheduler-related fields.
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468 * Set cpbase to the last timeout that occured (not the upcoming
469 * timeout).
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470 *
471 * A critical section is required since a timer IPI can update
472 * scheduler specific data.
a77ac49d 473 */
50017724 474 crit_enter();
a77ac49d 475 p2->p_usched = p1->p_usched;
553ea3c8 476 lp2->lwp_cpbase = mycpu->gd_schedclock.time -
dcc99b62 477 mycpu->gd_schedclock.periodic;
553ea3c8 478 p2->p_usched->heuristic_forking(&p1->p_lwp, lp2);
50017724 479 crit_exit();
a77ac49d 480
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481 /*
482 * This begins the section where we must prevent the parent
483 * from being swapped.
484 */
485 PHOLD(p1);
486
487 /*
488 * Finish creating the child process. It will return via a different
489 * execution path later. (ie: directly into user mode)
490 */
bb3cd951 491 vm_fork(lp1, p2, flags);
e30f9e2c 492 caps_fork(p1, p2, flags);
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493
494 if (flags == (RFFDG | RFPROC)) {
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495 mycpu->gd_cnt.v_forks++;
496 mycpu->gd_cnt.v_forkpages += p2->p_vmspace->vm_dsize + p2->p_vmspace->vm_ssize;
984263bc 497 } else if (flags == (RFFDG | RFPROC | RFPPWAIT | RFMEM)) {
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498 mycpu->gd_cnt.v_vforks++;
499 mycpu->gd_cnt.v_vforkpages += p2->p_vmspace->vm_dsize + p2->p_vmspace->vm_ssize;
984263bc 500 } else if (p1 == &proc0) {
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501 mycpu->gd_cnt.v_kthreads++;
502 mycpu->gd_cnt.v_kthreadpages += p2->p_vmspace->vm_dsize + p2->p_vmspace->vm_ssize;
984263bc 503 } else {
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504 mycpu->gd_cnt.v_rforks++;
505 mycpu->gd_cnt.v_rforkpages += p2->p_vmspace->vm_dsize + p2->p_vmspace->vm_ssize;
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506 }
507
508 /*
509 * Both processes are set up, now check if any loadable modules want
510 * to adjust anything.
511 * What if they have an error? XXX
512 */
513 TAILQ_FOREACH(ep, &fork_list, next) {
514 (*ep->function)(p1, p2, flags);
515 }
516
517 /*
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518 * Set the start time. Note that the process is not runnable. The
519 * caller is responsible for making it runnable.
984263bc 520 */
d9fa5f67 521 microtime(&p2->p_start);
984263bc 522 p2->p_acflag = AFORK;
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523
524 /*
525 * tell any interested parties about the new process
526 */
527 KNOTE(&p1->p_klist, NOTE_FORK | p2->p_pid);
528
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529 /*
530 * Return child proc pointer to parent.
531 */
532 *procp = p2;
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533done:
534 if (pgrp)
535 lockmgr(&pgrp->pg_lock, LK_RELEASE);
536 return (error);
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537}
538
539/*
540 * The next two functionms are general routines to handle adding/deleting
541 * items on the fork callout list.
542 *
543 * at_fork():
544 * Take the arguments given and put them onto the fork callout list,
545 * However first make sure that it's not already there.
546 * Returns 0 on success or a standard error number.
547 */
984263bc 548int
303c76d5 549at_fork(forklist_fn function)
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550{
551 struct forklist *ep;
552
553#ifdef INVARIANTS
554 /* let the programmer know if he's been stupid */
303c76d5 555 if (rm_at_fork(function)) {
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556 printf("WARNING: fork callout entry (%p) already present\n",
557 function);
303c76d5 558 }
984263bc 559#endif
efda3bd0 560 ep = kmalloc(sizeof(*ep), M_ATFORK, M_WAITOK|M_ZERO);
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561 ep->function = function;
562 TAILQ_INSERT_TAIL(&fork_list, ep, next);
563 return (0);
564}
565
566/*
567 * Scan the exit callout list for the given item and remove it..
568 * Returns the number of items removed (0 or 1)
569 */
984263bc 570int
303c76d5 571rm_at_fork(forklist_fn function)
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572{
573 struct forklist *ep;
574
575 TAILQ_FOREACH(ep, &fork_list, next) {
576 if (ep->function == function) {
577 TAILQ_REMOVE(&fork_list, ep, next);
efda3bd0 578 kfree(ep, M_ATFORK);
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579 return(1);
580 }
581 }
582 return (0);
583}
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584
585/*
586 * Add a forked process to the run queue after any remaining setup, such
587 * as setting the fork handler, has been completed.
588 */
7d0bac62 589void
553ea3c8 590start_forked_proc(struct lwp *lp1, struct proc *p2)
7d0bac62 591{
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592 struct lwp *lp2;
593
594 KKASSERT(p2 != NULL && p2->p_nthreads == 1);
595
596 lp2 = LIST_FIRST(&p2->p_lwps);
597
7d0bac62 598 /*
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599 * Move from SIDL to RUN queue, and activate the process's thread.
600 * Activation of the thread effectively makes the process "a"
601 * current process, so we do not setrunqueue().
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602 *
603 * YYY setrunqueue works here but we should clean up the trampoline
604 * code so we just schedule the LWKT thread and let the trampoline
605 * deal with the userland scheduler on return to userland.
7d0bac62 606 */
553ea3c8 607 KASSERT(p2->p_stat == SIDL,
7d0bac62 608 ("cannot start forked process, bad status: %p", p2));
553ea3c8 609 p2->p_usched->resetpriority(lp2);
e43a034f 610 crit_enter();
7d0bac62 611 p2->p_stat = SRUN;
553ea3c8 612 p2->p_usched->setrunqueue(lp2);
e43a034f 613 crit_exit();
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614
615 /*
616 * Now can be swapped.
617 */
553ea3c8 618 PRELE(lp1->lwp_proc);
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619
620 /*
621 * Preserve synchronization semantics of vfork. If waiting for
622 * child to exec or exit, set P_PPWAIT on child, and sleep on our
623 * proc (in case of exit).
624 */
625 while (p2->p_flag & P_PPWAIT)
553ea3c8 626 tsleep(lp1->lwp_proc, 0, "ppwait", 0);
7d0bac62 627}