vm: fix potential null deref
[minix.git] / servers / rs / main.c
bloba4c070b43472930a205d9cd67cda7db2272a2b76
1 /* Reincarnation Server. This servers starts new system services and detects
2 * they are exiting. In case of errors, system services can be restarted.
3 * The RS server periodically checks the status of all registered services
4 * services to see whether they are still alive. The system services are
5 * expected to periodically send a heartbeat message.
6 *
7 * Changes:
8 * Nov 22, 2009: rewrite of boot process (Cristiano Giuffrida)
9 * Jul 22, 2005: Created (Jorrit N. Herder)
11 #include "inc.h"
12 #include <fcntl.h>
13 #include "kernel/const.h"
14 #include "kernel/type.h"
15 #include "kernel/proc.h"
17 /* Declare some local functions. */
18 static void boot_image_info_lookup( endpoint_t endpoint, struct
19 boot_image *image, struct boot_image **ip, struct boot_image_priv **pp,
20 struct boot_image_sys **sp, struct boot_image_dev **dp);
21 static void catch_boot_init_ready(endpoint_t endpoint);
22 static void get_work(message *m_ptr, int *status_ptr);
24 /* SEF functions and variables. */
25 static void sef_local_startup(void);
26 static int sef_cb_init_fresh(int type, sef_init_info_t *info);
27 static void sef_cb_signal_handler(int signo);
28 static int sef_cb_signal_manager(endpoint_t target, int signo);
31 /*===========================================================================*
32 * main *
33 *===========================================================================*/
34 int main(void)
36 /* This is the main routine of this service. The main loop consists of
37 * three major activities: getting new work, processing the work, and
38 * sending the reply. The loop never terminates, unless a panic occurs.
40 message m; /* request message */
41 int ipc_status; /* status code */
42 int call_nr, who_e,who_p; /* call number and caller */
43 int result; /* result to return */
44 int s;
46 /* SEF local startup. */
47 sef_local_startup();
49 if (OK != (s=sys_getmachine(&machine)))
50 panic("couldn't get machine info: %d", s);
52 if (OK != (s=sys_getkinfo(&kinfo)))
53 panic("couldn't get kernel kinfo: %d", s);
55 /* Main loop - get work and do it, forever. */
56 while (TRUE) {
58 /* Wait for request message. */
59 get_work(&m, &ipc_status);
60 who_e = m.m_source;
61 if(rs_isokendpt(who_e, &who_p) != OK) {
62 panic("message from bogus source: %d", who_e);
65 call_nr = m.m_type;
67 /* Now determine what to do. Four types of requests are expected:
68 * - Heartbeat messages (notifications from registered system services)
69 * - System notifications (synchronous alarm)
70 * - User requests (control messages to manage system services)
71 * - Ready messages (reply messages from registered services)
74 /* Notification messages are control messages and do not need a reply.
75 * These include heartbeat messages and system notifications.
77 if (is_ipc_notify(ipc_status)) {
78 switch (who_p) {
79 case CLOCK:
80 do_period(&m); /* check services status */
81 continue;
82 default: /* heartbeat notification */
83 if (rproc_ptr[who_p] != NULL) { /* mark heartbeat time */
84 rproc_ptr[who_p]->r_alive_tm = m.NOTIFY_TIMESTAMP;
85 } else {
86 printf("RS: warning: got unexpected notify message from %d\n",
87 m.m_source);
92 /* If we get this far, this is a normal request.
93 * Handle the request and send a reply to the caller.
95 else {
96 if (call_nr != COMMON_GETSYSINFO &&
97 (call_nr < RS_RQ_BASE || call_nr >= RS_RQ_BASE+0x100))
99 /* Ignore invalid requests. Do not try to reply. */
100 printf("RS: warning: got invalid request %d from endpoint %d\n",
101 call_nr, m.m_source);
102 continue;
105 /* Handler functions are responsible for permission checking. */
106 switch(call_nr) {
107 /* User requests. */
108 case RS_UP: result = do_up(&m); break;
109 case RS_DOWN: result = do_down(&m); break;
110 case RS_REFRESH: result = do_refresh(&m); break;
111 case RS_RESTART: result = do_restart(&m); break;
112 case RS_SHUTDOWN: result = do_shutdown(&m); break;
113 case RS_UPDATE: result = do_update(&m); break;
114 case RS_CLONE: result = do_clone(&m); break;
115 case RS_EDIT: result = do_edit(&m); break;
116 case COMMON_GETSYSINFO:
117 result = do_getsysinfo(&m); break;
118 case RS_LOOKUP: result = do_lookup(&m); break;
119 /* Ready messages. */
120 case RS_INIT: result = do_init_ready(&m); break;
121 case RS_LU_PREPARE: result = do_upd_ready(&m); break;
122 default:
123 printf("RS: warning: got unexpected request %d from %d\n",
124 m.m_type, m.m_source);
125 result = EINVAL;
128 /* Finally send reply message, unless disabled. */
129 if (result != EDONTREPLY) {
130 m.m_type = result;
131 reply(who_e, NULL, &m);
137 /*===========================================================================*
138 * sef_local_startup *
139 *===========================================================================*/
140 static void sef_local_startup()
142 /* Register init callbacks. */
143 sef_setcb_init_response(do_init_ready);
144 sef_setcb_init_fresh(sef_cb_init_fresh);
145 sef_setcb_init_restart(sef_cb_init_fail);
147 /* Register live update callbacks. */
148 sef_setcb_lu_response(do_upd_ready);
150 /* Register signal callbacks. */
151 sef_setcb_signal_handler(sef_cb_signal_handler);
152 sef_setcb_signal_manager(sef_cb_signal_manager);
154 /* Let SEF perform startup. */
155 sef_startup();
158 /*===========================================================================*
159 * sef_cb_init_fresh *
160 *===========================================================================*/
161 static int sef_cb_init_fresh(int UNUSED(type), sef_init_info_t *UNUSED(info))
163 /* Initialize the reincarnation server. */
164 struct boot_image *ip;
165 int s,i;
166 int nr_image_srvs, nr_image_priv_srvs, nr_uncaught_init_srvs;
167 struct rproc *rp;
168 struct rprocpub *rpub;
169 struct boot_image image[NR_BOOT_PROCS];
170 struct boot_image_priv *boot_image_priv;
171 struct boot_image_sys *boot_image_sys;
172 struct boot_image_dev *boot_image_dev;
173 int ipc_to;
174 int *calls;
175 int all_c[] = { ALL_C, NULL_C };
176 int no_c[] = { NULL_C };
178 /* See if we run in verbose mode. */
179 env_parse("rs_verbose", "d", 0, &rs_verbose, 0, 1);
181 if ((s = sys_getinfo(GET_HZ, &system_hz, sizeof(system_hz), 0, 0)) != OK)
182 panic("Cannot get system timer frequency\n");
184 /* Initialize the global init descriptor. */
185 rinit.rproctab_gid = cpf_grant_direct(ANY, (vir_bytes) rprocpub,
186 sizeof(rprocpub), CPF_READ);
187 if(!GRANT_VALID(rinit.rproctab_gid)) {
188 panic("unable to create rprocpub table grant: %d", rinit.rproctab_gid);
191 /* Initialize some global variables. */
192 rupdate.flags = 0;
193 shutting_down = FALSE;
195 /* Get a copy of the boot image table. */
196 if ((s = sys_getimage(image)) != OK) {
197 panic("unable to get copy of boot image table: %d", s);
200 /* Determine the number of system services in the boot image table. */
201 nr_image_srvs = 0;
202 for(i=0;i<NR_BOOT_PROCS;i++) {
203 ip = &image[i];
205 /* System services only. */
206 if(iskerneln(_ENDPOINT_P(ip->endpoint))) {
207 continue;
209 nr_image_srvs++;
212 /* Determine the number of entries in the boot image priv table and make sure
213 * it matches the number of system services in the boot image table.
215 nr_image_priv_srvs = 0;
216 for (i=0; boot_image_priv_table[i].endpoint != NULL_BOOT_NR; i++) {
217 boot_image_priv = &boot_image_priv_table[i];
219 /* System services only. */
220 if(iskerneln(_ENDPOINT_P(boot_image_priv->endpoint))) {
221 continue;
223 nr_image_priv_srvs++;
225 if(nr_image_srvs != nr_image_priv_srvs) {
226 panic("boot image table and boot image priv table mismatch");
229 /* Reset the system process table. */
230 for (rp=BEG_RPROC_ADDR; rp<END_RPROC_ADDR; rp++) {
231 rp->r_flags = 0;
232 rp->r_pub = &rprocpub[rp - rproc];
233 rp->r_pub->in_use = FALSE;
236 /* Initialize the system process table in 4 steps, each of them following
237 * the appearance of system services in the boot image priv table.
238 * - Step 1: set priviliges, sys properties, and dev properties (if any)
239 * for every system service.
241 for (i=0; boot_image_priv_table[i].endpoint != NULL_BOOT_NR; i++) {
242 boot_image_priv = &boot_image_priv_table[i];
244 /* System services only. */
245 if(iskerneln(_ENDPOINT_P(boot_image_priv->endpoint))) {
246 continue;
249 /* Lookup the corresponding entries in other tables. */
250 boot_image_info_lookup(boot_image_priv->endpoint, image,
251 &ip, NULL, &boot_image_sys, &boot_image_dev);
252 rp = &rproc[boot_image_priv - boot_image_priv_table];
253 rpub = rp->r_pub;
256 * Set privileges.
258 /* Get label. */
259 strcpy(rpub->label, boot_image_priv->label);
261 /* Force a static priv id for system services in the boot image. */
262 rp->r_priv.s_id = static_priv_id(
263 _ENDPOINT_P(boot_image_priv->endpoint));
265 /* Initialize privilege bitmaps and signal manager. */
266 rp->r_priv.s_flags = boot_image_priv->flags; /* priv flags */
267 rp->r_priv.s_trap_mask= SRV_OR_USR(rp, SRV_T, USR_T); /* traps */
268 ipc_to = SRV_OR_USR(rp, SRV_M, USR_M); /* targets */
269 fill_send_mask(&rp->r_priv.s_ipc_to, ipc_to == ALL_M);
270 rp->r_priv.s_sig_mgr= SRV_OR_USR(rp, SRV_SM, USR_SM); /* sig mgr */
271 rp->r_priv.s_bak_sig_mgr = NONE; /* backup sig mgr */
273 /* Initialize kernel call mask bitmap. */
274 calls = SRV_OR_USR(rp, SRV_KC, USR_KC) == ALL_C ? all_c : no_c;
275 fill_call_mask(calls, NR_SYS_CALLS,
276 rp->r_priv.s_k_call_mask, KERNEL_CALL, TRUE);
278 /* Set the privilege structure. RS and VM are exceptions and are already
279 * running.
281 if(boot_image_priv->endpoint != RS_PROC_NR &&
282 boot_image_priv->endpoint != VM_PROC_NR) {
283 if ((s = sys_privctl(ip->endpoint, SYS_PRIV_SET_SYS, &(rp->r_priv)))
284 != OK) {
285 panic("unable to set privilege structure: %d", s);
289 /* Synch the privilege structure with the kernel. */
290 if ((s = sys_getpriv(&(rp->r_priv), ip->endpoint)) != OK) {
291 panic("unable to synch privilege structure: %d", s);
295 * Set sys properties.
297 rpub->sys_flags = boot_image_sys->flags; /* sys flags */
300 * Set dev properties.
302 rpub->dev_flags = boot_image_dev->flags; /* device flags */
303 rpub->dev_nr = boot_image_dev->dev_nr; /* major device number */
304 rpub->dev_style = boot_image_dev->dev_style; /* device style */
305 rpub->dev_style2 = boot_image_dev->dev_style2; /* device style 2 */
307 /* Get process name. */
308 strcpy(rpub->proc_name, ip->proc_name);
310 /* Build command settings. */
311 rp->r_cmd[0]= '\0';
312 rp->r_script[0]= '\0';
313 build_cmd_dep(rp);
315 /* Initialize vm call mask bitmap. */
316 calls = SRV_OR_USR(rp, SRV_VC, USR_VC) == ALL_C ? all_c : no_c;
317 fill_call_mask(calls, NR_VM_CALLS, rpub->vm_call_mask, VM_RQ_BASE, TRUE);
319 /* Scheduling parameters. */
320 rp->r_scheduler = SRV_OR_USR(rp, SRV_SCH, USR_SCH);
321 rp->r_priority = SRV_OR_USR(rp, SRV_Q, USR_Q);
322 rp->r_quantum = SRV_OR_USR(rp, SRV_QT, USR_QT);
324 /* Get some settings from the boot image table. */
325 rpub->endpoint = ip->endpoint;
327 /* Set some defaults. */
328 rp->r_old_rp = NULL; /* no old version yet */
329 rp->r_new_rp = NULL; /* no new version yet */
330 rp->r_prev_rp = NULL; /* no prev replica yet */
331 rp->r_next_rp = NULL; /* no next replica yet */
332 rp->r_uid = 0; /* root */
333 rp->r_check_tm = 0; /* not checked yet */
334 getuptime(&rp->r_alive_tm); /* currently alive */
335 rp->r_stop_tm = 0; /* not exiting yet */
336 rp->r_restarts = 0; /* no restarts so far */
337 rp->r_period = 0; /* no period yet */
338 rp->r_exec = NULL; /* no in-memory copy yet */
339 rp->r_exec_len = 0;
341 /* Mark as in use and active. */
342 rp->r_flags = RS_IN_USE | RS_ACTIVE;
343 rproc_ptr[_ENDPOINT_P(rpub->endpoint)]= rp;
344 rpub->in_use = TRUE;
347 /* - Step 2: allow every system service in the boot image to run. */
348 nr_uncaught_init_srvs = 0;
349 for (i=0; boot_image_priv_table[i].endpoint != NULL_BOOT_NR; i++) {
350 boot_image_priv = &boot_image_priv_table[i];
352 /* System services only. */
353 if(iskerneln(_ENDPOINT_P(boot_image_priv->endpoint))) {
354 continue;
357 /* Lookup the corresponding slot in the system process table. */
358 rp = &rproc[boot_image_priv - boot_image_priv_table];
359 rpub = rp->r_pub;
361 /* RS/VM are already running as we speak. */
362 if(boot_image_priv->endpoint == RS_PROC_NR ||
363 boot_image_priv->endpoint == VM_PROC_NR) {
364 if ((s = init_service(rp, SEF_INIT_FRESH)) != OK) {
365 panic("unable to initialize %d: %d", boot_image_priv->endpoint, s);
367 continue;
370 /* Allow the service to run. */
371 if ((s = sched_init_proc(rp)) != OK) {
372 panic("unable to initialize scheduling: %d", s);
374 if ((s = sys_privctl(rpub->endpoint, SYS_PRIV_ALLOW, NULL)) != OK) {
375 panic("unable to initialize privileges: %d", s);
378 /* Initialize service. We assume every service will always get
379 * back to us here at boot time.
381 if(boot_image_priv->flags & SYS_PROC) {
382 if ((s = init_service(rp, SEF_INIT_FRESH)) != OK) {
383 panic("unable to initialize service: %d", s);
385 if(rpub->sys_flags & SF_SYNCH_BOOT) {
386 /* Catch init ready message now to synchronize. */
387 catch_boot_init_ready(rpub->endpoint);
389 else {
390 /* Catch init ready message later. */
391 nr_uncaught_init_srvs++;
396 /* - Step 3: let every system service complete initialization by
397 * catching all the init ready messages left.
399 while(nr_uncaught_init_srvs) {
400 catch_boot_init_ready(ANY);
401 nr_uncaught_init_srvs--;
404 /* - Step 4: all the system services in the boot image are now running.
405 * Complete the initialization of the system process table in collaboration
406 * with other system services.
408 for (i=0; boot_image_priv_table[i].endpoint != NULL_BOOT_NR; i++) {
409 boot_image_priv = &boot_image_priv_table[i];
411 /* System services only. */
412 if(iskerneln(_ENDPOINT_P(boot_image_priv->endpoint))) {
413 continue;
416 /* Lookup the corresponding slot in the system process table. */
417 rp = &rproc[boot_image_priv - boot_image_priv_table];
418 rpub = rp->r_pub;
420 /* Get pid from PM. */
421 rp->r_pid = getnpid(rpub->endpoint);
422 if(rp->r_pid == -1) {
423 panic("unable to get pid");
427 /* Set alarm to periodically check service status. */
428 if (OK != (s=sys_setalarm(RS_DELTA_T, 0)))
429 panic("couldn't set alarm: %d", s);
431 #if USE_LIVEUPDATE
432 /* Now create a new RS instance and let the current
433 * instance live update into the replica. Clone RS' own slot first.
435 rp = rproc_ptr[_ENDPOINT_P(RS_PROC_NR)];
436 if((s = clone_slot(rp, &replica_rp)) != OK) {
437 panic("unable to clone current RS instance: %d", s);
440 /* Fork a new RS instance with root:operator. */
441 pid = srv_fork(0, 0);
442 if(pid == -1) {
443 panic("unable to fork a new RS instance");
445 replica_pid = pid ? pid : getpid();
446 replica_endpoint = getnprocnr(replica_pid);
447 replica_rp->r_pid = replica_pid;
448 replica_rp->r_pub->endpoint = replica_endpoint;
450 if(pid == 0) {
451 /* New RS instance running. */
453 /* Live update the old instance into the new one. */
454 s = update_service(&rp, &replica_rp, RS_SWAP);
455 if(s != OK) {
456 panic("unable to live update RS: %d", s);
458 cpf_reload();
460 /* Clean up the old RS instance, the new instance will take over. */
461 cleanup_service(rp);
463 /* Ask VM to pin memory for the new RS instance. */
464 if((s = vm_memctl(RS_PROC_NR, VM_RS_MEM_PIN)) != OK) {
465 panic("unable to pin memory for the new RS instance: %d", s);
468 else {
469 /* Old RS instance running. */
471 /* Set up privileges for the new instance and let it run. */
472 s = sys_privctl(replica_endpoint, SYS_PRIV_SET_SYS, &(replica_rp->r_priv));
473 if(s != OK) {
474 panic("unable to set privileges for the new RS instance: %d", s);
476 if ((s = sched_init_proc(replica_rp)) != OK) {
477 panic("unable to initialize RS replica scheduling: %d", s);
479 s = sys_privctl(replica_endpoint, SYS_PRIV_YIELD, NULL);
480 if(s != OK) {
481 panic("unable to yield control to the new RS instance: %d", s);
483 NOT_REACHABLE;
485 #endif /* USE_LIVEUPDATE */
487 return(OK);
490 /*===========================================================================*
491 * sef_cb_signal_handler *
492 *===========================================================================*/
493 static void sef_cb_signal_handler(int signo)
495 /* Check for known signals, ignore anything else. */
496 switch(signo) {
497 case SIGCHLD:
498 do_sigchld();
499 break;
500 case SIGTERM:
501 do_shutdown(NULL);
502 break;
506 /*===========================================================================*
507 * sef_cb_signal_manager *
508 *===========================================================================*/
509 static int sef_cb_signal_manager(endpoint_t target, int signo)
511 /* Process system signal on behalf of the kernel. */
512 int target_p;
513 struct rproc *rp;
514 struct rprocpub *rpub;
515 message m;
517 /* Lookup slot. */
518 if(rs_isokendpt(target, &target_p) != OK || rproc_ptr[target_p] == NULL) {
519 if(rs_verbose)
520 printf("RS: ignoring spurious signal %d for process %d\n",
521 signo, target);
522 return OK; /* clear the signal */
524 rp = rproc_ptr[target_p];
525 rpub = rp->r_pub;
527 /* Don't bother if a termination signal has already been processed. */
528 if((rp->r_flags & RS_TERMINATED) && !(rp->r_flags & RS_EXITING)) {
529 return EDEADEPT; /* process is gone */
532 /* Ignore external signals for inactive service instances. */
533 if( !(rp->r_flags & RS_ACTIVE) && !(rp->r_flags & RS_EXITING)) {
534 if(rs_verbose)
535 printf("RS: ignoring signal %d for inactive %s\n",
536 signo, srv_to_string(rp));
537 return OK; /* clear the signal */
540 if(rs_verbose)
541 printf("RS: %s got %s signal %d\n", srv_to_string(rp),
542 SIGS_IS_TERMINATION(signo) ? "termination" : "non-termination",signo);
544 /* Print stacktrace if necessary. */
545 if(SIGS_IS_STACKTRACE(signo)) {
546 sys_sysctl_stacktrace(target);
549 /* In case of termination signal handle the event. */
550 if(SIGS_IS_TERMINATION(signo)) {
551 rp->r_flags |= RS_TERMINATED;
552 terminate_service(rp);
554 return EDEADEPT; /* process is now gone */
557 /* Translate every non-termination signal into a message. */
558 m.m_type = SIGS_SIGNAL_RECEIVED;
559 m.SIGS_SIG_NUM = signo;
560 asynsend3(rpub->endpoint, &m, AMF_NOREPLY);
562 return OK; /* signal has been delivered */
565 /*===========================================================================*
566 * boot_image_info_lookup *
567 *===========================================================================*/
568 static void boot_image_info_lookup(endpoint, image, ip, pp, sp, dp)
569 endpoint_t endpoint;
570 struct boot_image *image;
571 struct boot_image **ip;
572 struct boot_image_priv **pp;
573 struct boot_image_sys **sp;
574 struct boot_image_dev **dp;
576 /* Lookup entries in boot image tables. */
577 int i;
579 /* When requested, locate the corresponding entry in the boot image table
580 * or panic if not found.
582 if(ip) {
583 for (i=0; i < NR_BOOT_PROCS; i++) {
584 if(image[i].endpoint == endpoint) {
585 *ip = &image[i];
586 break;
589 if(i == NR_BOOT_PROCS) {
590 panic("boot image table lookup failed");
594 /* When requested, locate the corresponding entry in the boot image priv table
595 * or panic if not found.
597 if(pp) {
598 for (i=0; boot_image_priv_table[i].endpoint != NULL_BOOT_NR; i++) {
599 if(boot_image_priv_table[i].endpoint == endpoint) {
600 *pp = &boot_image_priv_table[i];
601 break;
604 if(i == NULL_BOOT_NR) {
605 panic("boot image priv table lookup failed");
609 /* When requested, locate the corresponding entry in the boot image sys table
610 * or resort to the default entry if not found.
612 if(sp) {
613 for (i=0; boot_image_sys_table[i].endpoint != DEFAULT_BOOT_NR; i++) {
614 if(boot_image_sys_table[i].endpoint == endpoint) {
615 *sp = &boot_image_sys_table[i];
616 break;
619 if(boot_image_sys_table[i].endpoint == DEFAULT_BOOT_NR) {
620 *sp = &boot_image_sys_table[i]; /* accept the default entry */
624 /* When requested, locate the corresponding entry in the boot image dev table
625 * or resort to the default entry if not found.
627 if(dp) {
628 for (i=0; boot_image_dev_table[i].endpoint != DEFAULT_BOOT_NR; i++) {
629 if(boot_image_dev_table[i].endpoint == endpoint) {
630 *dp = &boot_image_dev_table[i];
631 break;
634 if(boot_image_dev_table[i].endpoint == DEFAULT_BOOT_NR) {
635 *dp = &boot_image_dev_table[i]; /* accept the default entry */
640 /*===========================================================================*
641 * catch_boot_init_ready *
642 *===========================================================================*/
643 static void catch_boot_init_ready(endpoint)
644 endpoint_t endpoint;
646 /* Block and catch an init ready message from the given source. */
647 int r;
648 int ipc_status;
649 message m;
650 struct rproc *rp;
651 int result;
653 /* Receive init ready message. */
654 if ((r = sef_receive_status(endpoint, &m, &ipc_status)) != OK) {
655 panic("unable to receive init reply: %d", r);
657 if(m.m_type != RS_INIT) {
658 panic("unexpected reply from service: %d", m.m_source);
660 result = m.RS_INIT_RESULT;
661 rp = rproc_ptr[_ENDPOINT_P(m.m_source)];
663 /* Check result. */
664 if(result != OK) {
665 panic("unable to complete init for service: %d", m.m_source);
668 /* Send a reply to unblock the service. */
669 m.m_type = OK;
670 reply(m.m_source, rp, &m);
672 /* Mark the slot as no longer initializing. */
673 rp->r_flags &= ~RS_INITIALIZING;
674 rp->r_check_tm = 0;
675 getuptime(&rp->r_alive_tm);
678 /*===========================================================================*
679 * get_work *
680 *===========================================================================*/
681 static void get_work(m_ptr, status_ptr)
682 message *m_ptr; /* pointer to message */
683 int *status_ptr; /* pointer to status */
685 int r;
686 if (OK != (r=sef_receive_status(ANY, m_ptr, status_ptr)))
687 panic("sef_receive_status failed: %d", r);