1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 * Copyright 2012, Joyent, Inc. All rights reserved. 25 */ 26 27 /* 28 * wait.c - asynchronous monitoring of "wait registered" start methods 29 * 30 * Use event ports to poll on the set of fds representing the /proc/[pid]/psinfo 31 * files. If one of these fds returns an event, then we inform the restarter 32 * that it has stopped. 33 * 34 * The wait_info_list holds the series of processes currently being monitored 35 * for exit. The wi_fd member, which contains the file descriptor of the psinfo 36 * file being polled upon ("event ported upon"), will be set to -1 if the file 37 * descriptor is inactive (already closed or not yet opened). 38 */ 39 40 #ifdef _FILE_OFFSET_BITS 41 #undef _FILE_OFFSET_BITS 42 #endif /* _FILE_OFFSET_BITS */ 43 44 #include <sys/resource.h> 45 #include <sys/stat.h> 46 #include <sys/types.h> 47 #include <sys/uio.h> 48 #include <sys/wait.h> 49 50 #include <assert.h> 51 #include <errno.h> 52 #include <fcntl.h> 53 #include <libuutil.h> 54 #include <poll.h> 55 #include <port.h> 56 #include <pthread.h> 57 #include <procfs.h> 58 #include <string.h> 59 #include <stropts.h> 60 #include <unistd.h> 61 62 #include "startd.h" 63 64 #define WAIT_FILES 262144 /* reasonably high maximum */ 65 66 static int port_fd; 67 static scf_handle_t *wait_hndl; 68 static struct rlimit init_fd_rlimit; 69 70 static uu_list_pool_t *wait_info_pool; 71 static uu_list_t *wait_info_list; 72 73 static pthread_mutex_t wait_info_lock; 74 75 /* 76 * void wait_remove(wait_info_t *, int) 77 * Remove the given wait_info structure from our list, performing various 78 * cleanup operations along the way. If the direct flag is false (meaning 79 * that we are being called with from restarter instance list context) and 80 * the instance should not be ignored, then notify the restarter that the 81 * associated instance has exited. If the wi_ignore flag is true then it 82 * means that the stop was initiated from within svc.startd, rather than 83 * from outside it. 84 * 85 * Since we may no longer be the startd that started this process, we only are 86 * concerned with a waitpid(3C) failure if the wi_parent field is non-zero. 87 */ 88 static void 89 wait_remove(wait_info_t *wi, int direct) 90 { 91 int status; 92 stop_cause_t cause = RSTOP_EXIT; 93 94 if (waitpid(wi->wi_pid, &status, 0) == -1) { 95 if (wi->wi_parent) 96 log_framework(LOG_INFO, 97 "instance %s waitpid failure: %s\n", wi->wi_fmri, 98 strerror(errno)); 99 } else { 100 if (WEXITSTATUS(status) != 0) { 101 log_framework(LOG_NOTICE, 102 "instance %s exited with status %d\n", wi->wi_fmri, 103 WEXITSTATUS(status)); 104 if (WEXITSTATUS(status) == SMF_EXIT_ERR_CONFIG) 105 cause = RSTOP_ERR_CFG; 106 else 107 cause = RSTOP_ERR_EXIT; 108 } 109 } 110 111 MUTEX_LOCK(&wait_info_lock); 112 if (wi->wi_fd != -1) { 113 startd_close(wi->wi_fd); 114 wi->wi_fd = -1; 115 } 116 uu_list_remove(wait_info_list, wi); 117 MUTEX_UNLOCK(&wait_info_lock); 118 119 /* 120 * Make an attempt to clear out any utmpx record associated with this 121 * PID. 122 */ 123 utmpx_mark_dead(wi->wi_pid, status, B_FALSE); 124 125 if (!direct && !wi->wi_ignore) { 126 /* 127 * Bind wait_hndl lazily. 128 */ 129 if (wait_hndl == NULL) { 130 for (wait_hndl = 131 libscf_handle_create_bound(SCF_VERSION); 132 wait_hndl == NULL; 133 wait_hndl = 134 libscf_handle_create_bound(SCF_VERSION)) { 135 log_error(LOG_INFO, "[wait_remove] Unable to " 136 "bind a new repository handle: %s\n", 137 scf_strerror(scf_error())); 138 (void) sleep(2); 139 } 140 } 141 142 log_framework(LOG_DEBUG, 143 "wait_remove requesting stop of %s\n", wi->wi_fmri); 144 (void) stop_instance_fmri(wait_hndl, wi->wi_fmri, cause); 145 } 146 147 uu_list_node_fini(wi, &wi->wi_link, wait_info_pool); 148 startd_free(wi, sizeof (wait_info_t)); 149 } 150 151 /* 152 * void wait_ignore_by_fmri(const char *) 153 * wait_ignore_by_fmri is called when svc.startd is going to stop the 154 * instance. Since we need to wait on the process and close the utmpx record, 155 * we're going to set the wi_ignore flag, so that when the process exits we 156 * clean up, but don't tell the restarter to stop it. 157 */ 158 void 159 wait_ignore_by_fmri(const char *fmri) 160 { 161 wait_info_t *wi; 162 163 MUTEX_LOCK(&wait_info_lock); 164 165 for (wi = uu_list_first(wait_info_list); wi != NULL; 166 wi = uu_list_next(wait_info_list, wi)) { 167 if (strcmp(wi->wi_fmri, fmri) == 0) 168 break; 169 } 170 171 if (wi != NULL) { 172 wi->wi_ignore = 1; 173 } 174 175 MUTEX_UNLOCK(&wait_info_lock); 176 } 177 178 /* 179 * int wait_register(pid_t, char *, int, int) 180 * wait_register is called after we have called fork(2), and know which pid we 181 * wish to monitor. However, since the child may have already exited by the 182 * time we are called, we must handle the error cases from open(2) 183 * appropriately. The am_parent flag is recorded to handle waitpid(2) 184 * behaviour on removal; similarly, the direct flag is passed through to a 185 * potential call to wait_remove() to govern its behaviour in different 186 * contexts. 187 * 188 * Returns 0 if registration successful, 1 if child pid did not exist, and -1 189 * if a different error occurred. 190 */ 191 int 192 wait_register(pid_t pid, const char *inst_fmri, int am_parent, int direct) 193 { 194 char *fname = uu_msprintf("/proc/%ld/psinfo", pid); 195 int fd; 196 wait_info_t *wi; 197 198 assert(pid != 0); 199 200 if (fname == NULL) 201 return (-1); 202 203 wi = startd_alloc(sizeof (wait_info_t)); 204 205 uu_list_node_init(wi, &wi->wi_link, wait_info_pool); 206 207 wi->wi_fd = -1; 208 wi->wi_pid = pid; 209 wi->wi_fmri = inst_fmri; 210 wi->wi_parent = am_parent; 211 wi->wi_ignore = 0; 212 213 MUTEX_LOCK(&wait_info_lock); 214 (void) uu_list_insert_before(wait_info_list, NULL, wi); 215 MUTEX_UNLOCK(&wait_info_lock); 216 217 if ((fd = open(fname, O_RDONLY)) == -1) { 218 if (errno == ENOENT) { 219 /* 220 * Child has already exited. 221 */ 222 wait_remove(wi, direct); 223 uu_free(fname); 224 return (1); 225 } else { 226 log_error(LOG_WARNING, 227 "open %s failed; not monitoring %s: %s\n", fname, 228 inst_fmri, strerror(errno)); 229 uu_free(fname); 230 return (-1); 231 } 232 } 233 234 uu_free(fname); 235 236 wi->wi_fd = fd; 237 238 if (port_associate(port_fd, PORT_SOURCE_FD, fd, 0, wi)) { 239 log_error(LOG_WARNING, 240 "initial port_association of %d / %s failed: %s\n", fd, 241 inst_fmri, strerror(errno)); 242 return (-1); 243 } 244 245 log_framework(LOG_DEBUG, "monitoring PID %ld on fd %d (%s)\n", pid, fd, 246 inst_fmri); 247 248 return (0); 249 } 250 251 /*ARGSUSED*/ 252 void * 253 wait_thread(void *args) 254 { 255 for (;;) { 256 port_event_t pe; 257 int fd; 258 wait_info_t *wi; 259 260 if (port_get(port_fd, &pe, NULL) != 0) { 261 if (errno == EINTR) 262 continue; 263 else { 264 log_error(LOG_WARNING, 265 "port_get() failed with %s\n", 266 strerror(errno)); 267 bad_error("port_get", errno); 268 } 269 } 270 271 fd = pe.portev_object; 272 wi = pe.portev_user; 273 assert(wi != NULL); 274 assert(fd == wi->wi_fd); 275 276 if ((pe.portev_events & POLLHUP) == POLLHUP) { 277 psinfo_t psi; 278 279 if (lseek(fd, 0, SEEK_SET) != 0 || 280 read(fd, &psi, sizeof (psinfo_t)) != 281 sizeof (psinfo_t)) { 282 log_framework(LOG_WARNING, 283 "couldn't get psinfo data for %s (%s); " 284 "assuming failed\n", wi->wi_fmri, 285 strerror(errno)); 286 goto err_remove; 287 } 288 289 if (psi.pr_nlwp != 0 || 290 psi.pr_nzomb != 0 || 291 psi.pr_lwp.pr_lwpid != 0) { 292 /* 293 * We have determined, in accordance with the 294 * definition in proc(4), this process is not a 295 * zombie. Reassociate. 296 */ 297 if (port_associate(port_fd, PORT_SOURCE_FD, fd, 298 0, wi)) 299 log_error(LOG_WARNING, 300 "port_association of %d / %s " 301 "failed\n", fd, wi->wi_fmri); 302 continue; 303 } 304 } else if ( 305 (pe.portev_events & POLLERR) == 0) { 306 if (port_associate(port_fd, PORT_SOURCE_FD, fd, 0, wi)) 307 log_error(LOG_WARNING, 308 "port_association of %d / %s " 309 "failed\n", fd, wi->wi_fmri); 310 continue; 311 } 312 313 err_remove: 314 wait_remove(wi, 0); 315 } 316 317 /*LINTED E_FUNC_HAS_NO_RETURN_STMT*/ 318 } 319 320 void 321 wait_prefork() 322 { 323 MUTEX_LOCK(&wait_info_lock); 324 } 325 326 void 327 wait_postfork(pid_t pid) 328 { 329 wait_info_t *wi; 330 331 MUTEX_UNLOCK(&wait_info_lock); 332 333 if (pid != 0) 334 return; 335 336 /* 337 * Close all of the child's wait-related fds. The wait_thread() is 338 * gone, so no need to worry about returning events. We always exec(2) 339 * after a fork request, so we needn't free the list elements 340 * themselves. 341 */ 342 343 for (wi = uu_list_first(wait_info_list); 344 wi != NULL; 345 wi = uu_list_next(wait_info_list, wi)) { 346 if (wi->wi_fd != -1) 347 startd_close(wi->wi_fd); 348 } 349 350 startd_close(port_fd); 351 352 (void) setrlimit(RLIMIT_NOFILE, &init_fd_rlimit); 353 } 354 355 void 356 wait_init() 357 { 358 struct rlimit fd_new; 359 360 (void) getrlimit(RLIMIT_NOFILE, &init_fd_rlimit); 361 (void) getrlimit(RLIMIT_NOFILE, &fd_new); 362 363 fd_new.rlim_max = fd_new.rlim_cur = WAIT_FILES; 364 365 (void) setrlimit(RLIMIT_NOFILE, &fd_new); 366 367 if ((port_fd = port_create()) == -1) 368 uu_die("wait_init couldn't port_create"); 369 370 wait_info_pool = uu_list_pool_create("wait_info", sizeof (wait_info_t), 371 offsetof(wait_info_t, wi_link), NULL, UU_LIST_POOL_DEBUG); 372 if (wait_info_pool == NULL) 373 uu_die("wait_init couldn't create wait_info_pool"); 374 375 wait_info_list = uu_list_create(wait_info_pool, wait_info_list, 0); 376 if (wait_info_list == NULL) 377 uu_die("wait_init couldn't create wait_info_list"); 378 379 (void) pthread_mutex_init(&wait_info_lock, &mutex_attrs); 380 } 381