1 /* 2 * linux/fs/proc/array.c 3 * 4 * Copyright (C) 1992 by Linus Torvalds 5 * based on ideas by Darren Senn 6 * 7 * Fixes: 8 * Michael. K. Johnson: stat,statm extensions. 9 * <johnsonm@stolaf.edu> 10 * 11 * Pauline Middelink : Made cmdline,envline only break at '\0's, to 12 * make sure SET_PROCTITLE works. Also removed 13 * bad '!' which forced address recalculation for 14 * EVERY character on the current page. 15 * <middelin@polyware.iaf.nl> 16 * 17 * Danny ter Haar : added cpuinfo 18 * <dth@cistron.nl> 19 * 20 * Alessandro Rubini : profile extension. 21 * <rubini@ipvvis.unipv.it> 22 * 23 * Jeff Tranter : added BogoMips field to cpuinfo 24 * <Jeff_Tranter@Mitel.COM> 25 * 26 * Bruno Haible : remove 4K limit for the maps file 27 * <haible@ma2s2.mathematik.uni-karlsruhe.de> 28 * 29 * Yves Arrouye : remove removal of trailing spaces in get_array. 30 * <Yves.Arrouye@marin.fdn.fr> 31 * 32 * Jerome Forissier : added per-CPU time information to /proc/stat 33 * and /proc/<pid>/cpu extension 34 * <forissier@isia.cma.fr> 35 * - Incorporation and non-SMP safe operation 36 * of forissier patch in 2.1.78 by 37 * Hans Marcus <crowbar@concepts.nl> 38 * 39 * aeb@cwi.nl : /proc/partitions 40 * 41 * 42 * Alan Cox : security fixes. 43 * <alan@lxorguk.ukuu.org.uk> 44 * 45 * Al Viro : safe handling of mm_struct 46 * 47 * Gerhard Wichert : added BIGMEM support 48 * Siemens AG <Gerhard.Wichert@pdb.siemens.de> 49 * 50 * Al Viro & Jeff Garzik : moved most of the thing into base.c and 51 * : proc_misc.c. The rest may eventually go into 52 * : base.c too. 53 */ 54 55 #include <linux/types.h> 56 #include <linux/errno.h> 57 #include <linux/time.h> 58 #include <linux/kernel.h> 59 #include <linux/kernel_stat.h> 60 #include <linux/tty.h> 61 #include <linux/string.h> 62 #include <linux/mman.h> 63 #include <linux/proc_fs.h> 64 #include <linux/ioport.h> 65 #include <linux/uaccess.h> 66 #include <linux/io.h> 67 #include <linux/mm.h> 68 #include <linux/hugetlb.h> 69 #include <linux/pagemap.h> 70 #include <linux/swap.h> 71 #include <linux/smp.h> 72 #include <linux/signal.h> 73 #include <linux/highmem.h> 74 #include <linux/file.h> 75 #include <linux/fdtable.h> 76 #include <linux/times.h> 77 #include <linux/cpuset.h> 78 #include <linux/rcupdate.h> 79 #include <linux/delayacct.h> 80 #include <linux/seq_file.h> 81 #include <linux/pid_namespace.h> 82 #include <linux/ptrace.h> 83 #include <linux/tracehook.h> 84 #include <linux/string_helpers.h> 85 #include <linux/user_namespace.h> 86 87 #include <asm/pgtable.h> 88 #include <asm/processor.h> 89 #include "internal.h" 90 91 static inline void task_name(struct seq_file *m, struct task_struct *p) 92 { 93 char *buf; 94 char tcomm[sizeof(p->comm)]; 95 96 get_task_comm(tcomm, p); 97 98 seq_puts(m, "Name:\t"); 99 buf = m->buf + m->count; 100 101 /* Ignore error for now */ 102 buf += string_escape_str(tcomm, buf, m->size - m->count, 103 ESCAPE_SPACE | ESCAPE_SPECIAL, "\n\\"); 104 105 m->count = buf - m->buf; 106 seq_putc(m, '\n'); 107 } 108 109 /* 110 * The task state array is a strange "bitmap" of 111 * reasons to sleep. Thus "running" is zero, and 112 * you can test for combinations of others with 113 * simple bit tests. 114 */ 115 static const char * const task_state_array[] = { 116 "R (running)", /* 0 */ 117 "S (sleeping)", /* 1 */ 118 "D (disk sleep)", /* 2 */ 119 "T (stopped)", /* 4 */ 120 "t (tracing stop)", /* 8 */ 121 "X (dead)", /* 16 */ 122 "Z (zombie)", /* 32 */ 123 }; 124 125 static inline const char *get_task_state(struct task_struct *tsk) 126 { 127 unsigned int state = (tsk->state | tsk->exit_state) & TASK_REPORT; 128 129 BUILD_BUG_ON(1 + ilog2(TASK_REPORT) != ARRAY_SIZE(task_state_array)-1); 130 131 return task_state_array[fls(state)]; 132 } 133 134 static inline void task_state(struct seq_file *m, struct pid_namespace *ns, 135 struct pid *pid, struct task_struct *p) 136 { 137 struct user_namespace *user_ns = seq_user_ns(m); 138 struct group_info *group_info; 139 int g; 140 struct task_struct *tracer; 141 const struct cred *cred; 142 pid_t ppid, tpid = 0, tgid, ngid; 143 unsigned int max_fds = 0; 144 145 rcu_read_lock(); 146 ppid = pid_alive(p) ? 147 task_tgid_nr_ns(rcu_dereference(p->real_parent), ns) : 0; 148 149 tracer = ptrace_parent(p); 150 if (tracer) 151 tpid = task_pid_nr_ns(tracer, ns); 152 153 tgid = task_tgid_nr_ns(p, ns); 154 ngid = task_numa_group_id(p); 155 cred = get_task_cred(p); 156 157 task_lock(p); 158 if (p->files) 159 max_fds = files_fdtable(p->files)->max_fds; 160 task_unlock(p); 161 rcu_read_unlock(); 162 163 seq_printf(m, 164 "State:\t%s\n" 165 "Tgid:\t%d\n" 166 "Ngid:\t%d\n" 167 "Pid:\t%d\n" 168 "PPid:\t%d\n" 169 "TracerPid:\t%d\n" 170 "Uid:\t%d\t%d\t%d\t%d\n" 171 "Gid:\t%d\t%d\t%d\t%d\n" 172 "FDSize:\t%d\nGroups:\t", 173 get_task_state(p), 174 tgid, ngid, pid_nr_ns(pid, ns), ppid, tpid, 175 from_kuid_munged(user_ns, cred->uid), 176 from_kuid_munged(user_ns, cred->euid), 177 from_kuid_munged(user_ns, cred->suid), 178 from_kuid_munged(user_ns, cred->fsuid), 179 from_kgid_munged(user_ns, cred->gid), 180 from_kgid_munged(user_ns, cred->egid), 181 from_kgid_munged(user_ns, cred->sgid), 182 from_kgid_munged(user_ns, cred->fsgid), 183 max_fds); 184 185 group_info = cred->group_info; 186 for (g = 0; g < group_info->ngroups; g++) 187 seq_printf(m, "%d ", 188 from_kgid_munged(user_ns, GROUP_AT(group_info, g))); 189 put_cred(cred); 190 191 #ifdef CONFIG_PID_NS 192 seq_puts(m, "\nNStgid:"); 193 for (g = ns->level; g <= pid->level; g++) 194 seq_printf(m, "\t%d", 195 task_tgid_nr_ns(p, pid->numbers[g].ns)); 196 seq_puts(m, "\nNSpid:"); 197 for (g = ns->level; g <= pid->level; g++) 198 seq_printf(m, "\t%d", 199 task_pid_nr_ns(p, pid->numbers[g].ns)); 200 seq_puts(m, "\nNSpgid:"); 201 for (g = ns->level; g <= pid->level; g++) 202 seq_printf(m, "\t%d", 203 task_pgrp_nr_ns(p, pid->numbers[g].ns)); 204 seq_puts(m, "\nNSsid:"); 205 for (g = ns->level; g <= pid->level; g++) 206 seq_printf(m, "\t%d", 207 task_session_nr_ns(p, pid->numbers[g].ns)); 208 #endif 209 seq_putc(m, '\n'); 210 } 211 212 void render_sigset_t(struct seq_file *m, const char *header, 213 sigset_t *set) 214 { 215 int i; 216 217 seq_puts(m, header); 218 219 i = _NSIG; 220 do { 221 int x = 0; 222 223 i -= 4; 224 if (sigismember(set, i+1)) x |= 1; 225 if (sigismember(set, i+2)) x |= 2; 226 if (sigismember(set, i+3)) x |= 4; 227 if (sigismember(set, i+4)) x |= 8; 228 seq_printf(m, "%x", x); 229 } while (i >= 4); 230 231 seq_putc(m, '\n'); 232 } 233 234 static void collect_sigign_sigcatch(struct task_struct *p, sigset_t *ign, 235 sigset_t *catch) 236 { 237 struct k_sigaction *k; 238 int i; 239 240 k = p->sighand->action; 241 for (i = 1; i <= _NSIG; ++i, ++k) { 242 if (k->sa.sa_handler == SIG_IGN) 243 sigaddset(ign, i); 244 else if (k->sa.sa_handler != SIG_DFL) 245 sigaddset(catch, i); 246 } 247 } 248 249 static inline void task_sig(struct seq_file *m, struct task_struct *p) 250 { 251 unsigned long flags; 252 sigset_t pending, shpending, blocked, ignored, caught; 253 int num_threads = 0; 254 unsigned long qsize = 0; 255 unsigned long qlim = 0; 256 257 sigemptyset(&pending); 258 sigemptyset(&shpending); 259 sigemptyset(&blocked); 260 sigemptyset(&ignored); 261 sigemptyset(&caught); 262 263 if (lock_task_sighand(p, &flags)) { 264 pending = p->pending.signal; 265 shpending = p->signal->shared_pending.signal; 266 blocked = p->blocked; 267 collect_sigign_sigcatch(p, &ignored, &caught); 268 num_threads = get_nr_threads(p); 269 rcu_read_lock(); /* FIXME: is this correct? */ 270 qsize = atomic_read(&__task_cred(p)->user->sigpending); 271 rcu_read_unlock(); 272 qlim = task_rlimit(p, RLIMIT_SIGPENDING); 273 unlock_task_sighand(p, &flags); 274 } 275 276 seq_printf(m, "Threads:\t%d\n", num_threads); 277 seq_printf(m, "SigQ:\t%lu/%lu\n", qsize, qlim); 278 279 /* render them all */ 280 render_sigset_t(m, "SigPnd:\t", &pending); 281 render_sigset_t(m, "ShdPnd:\t", &shpending); 282 render_sigset_t(m, "SigBlk:\t", &blocked); 283 render_sigset_t(m, "SigIgn:\t", &ignored); 284 render_sigset_t(m, "SigCgt:\t", &caught); 285 } 286 287 static void render_cap_t(struct seq_file *m, const char *header, 288 kernel_cap_t *a) 289 { 290 unsigned __capi; 291 292 seq_puts(m, header); 293 CAP_FOR_EACH_U32(__capi) { 294 seq_printf(m, "%08x", 295 a->cap[CAP_LAST_U32 - __capi]); 296 } 297 seq_putc(m, '\n'); 298 } 299 300 static inline void task_cap(struct seq_file *m, struct task_struct *p) 301 { 302 const struct cred *cred; 303 kernel_cap_t cap_inheritable, cap_permitted, cap_effective, cap_bset; 304 305 rcu_read_lock(); 306 cred = __task_cred(p); 307 cap_inheritable = cred->cap_inheritable; 308 cap_permitted = cred->cap_permitted; 309 cap_effective = cred->cap_effective; 310 cap_bset = cred->cap_bset; 311 rcu_read_unlock(); 312 313 render_cap_t(m, "CapInh:\t", &cap_inheritable); 314 render_cap_t(m, "CapPrm:\t", &cap_permitted); 315 render_cap_t(m, "CapEff:\t", &cap_effective); 316 render_cap_t(m, "CapBnd:\t", &cap_bset); 317 } 318 319 static inline void task_seccomp(struct seq_file *m, struct task_struct *p) 320 { 321 #ifdef CONFIG_SECCOMP 322 seq_printf(m, "Seccomp:\t%d\n", p->seccomp.mode); 323 #endif 324 } 325 326 static inline void task_context_switch_counts(struct seq_file *m, 327 struct task_struct *p) 328 { 329 seq_printf(m, "voluntary_ctxt_switches:\t%lu\n" 330 "nonvoluntary_ctxt_switches:\t%lu\n", 331 p->nvcsw, 332 p->nivcsw); 333 } 334 335 static void task_cpus_allowed(struct seq_file *m, struct task_struct *task) 336 { 337 seq_printf(m, "Cpus_allowed:\t%*pb\n", 338 cpumask_pr_args(&task->cpus_allowed)); 339 seq_printf(m, "Cpus_allowed_list:\t%*pbl\n", 340 cpumask_pr_args(&task->cpus_allowed)); 341 } 342 343 int proc_pid_status(struct seq_file *m, struct pid_namespace *ns, 344 struct pid *pid, struct task_struct *task) 345 { 346 struct mm_struct *mm = get_task_mm(task); 347 348 task_name(m, task); 349 task_state(m, ns, pid, task); 350 351 if (mm) { 352 task_mem(m, mm); 353 mmput(mm); 354 } 355 task_sig(m, task); 356 task_cap(m, task); 357 task_seccomp(m, task); 358 task_cpus_allowed(m, task); 359 cpuset_task_status_allowed(m, task); 360 task_context_switch_counts(m, task); 361 return 0; 362 } 363 364 static int do_task_stat(struct seq_file *m, struct pid_namespace *ns, 365 struct pid *pid, struct task_struct *task, int whole) 366 { 367 unsigned long vsize, eip, esp, wchan = ~0UL; 368 int priority, nice; 369 int tty_pgrp = -1, tty_nr = 0; 370 sigset_t sigign, sigcatch; 371 char state; 372 pid_t ppid = 0, pgid = -1, sid = -1; 373 int num_threads = 0; 374 int permitted; 375 struct mm_struct *mm; 376 unsigned long long start_time; 377 unsigned long cmin_flt = 0, cmaj_flt = 0; 378 unsigned long min_flt = 0, maj_flt = 0; 379 cputime_t cutime, cstime, utime, stime; 380 cputime_t cgtime, gtime; 381 unsigned long rsslim = 0; 382 char tcomm[sizeof(task->comm)]; 383 unsigned long flags; 384 385 state = *get_task_state(task); 386 vsize = eip = esp = 0; 387 permitted = ptrace_may_access(task, PTRACE_MODE_READ | PTRACE_MODE_NOAUDIT); 388 mm = get_task_mm(task); 389 if (mm) { 390 vsize = task_vsize(mm); 391 if (permitted) { 392 eip = KSTK_EIP(task); 393 esp = KSTK_ESP(task); 394 } 395 } 396 397 get_task_comm(tcomm, task); 398 399 sigemptyset(&sigign); 400 sigemptyset(&sigcatch); 401 cutime = cstime = utime = stime = 0; 402 cgtime = gtime = 0; 403 404 if (lock_task_sighand(task, &flags)) { 405 struct signal_struct *sig = task->signal; 406 407 if (sig->tty) { 408 struct pid *pgrp = tty_get_pgrp(sig->tty); 409 tty_pgrp = pid_nr_ns(pgrp, ns); 410 put_pid(pgrp); 411 tty_nr = new_encode_dev(tty_devnum(sig->tty)); 412 } 413 414 num_threads = get_nr_threads(task); 415 collect_sigign_sigcatch(task, &sigign, &sigcatch); 416 417 cmin_flt = sig->cmin_flt; 418 cmaj_flt = sig->cmaj_flt; 419 cutime = sig->cutime; 420 cstime = sig->cstime; 421 cgtime = sig->cgtime; 422 rsslim = ACCESS_ONCE(sig->rlim[RLIMIT_RSS].rlim_cur); 423 424 /* add up live thread stats at the group level */ 425 if (whole) { 426 struct task_struct *t = task; 427 do { 428 min_flt += t->min_flt; 429 maj_flt += t->maj_flt; 430 gtime += task_gtime(t); 431 } while_each_thread(task, t); 432 433 min_flt += sig->min_flt; 434 maj_flt += sig->maj_flt; 435 thread_group_cputime_adjusted(task, &utime, &stime); 436 gtime += sig->gtime; 437 } 438 439 sid = task_session_nr_ns(task, ns); 440 ppid = task_tgid_nr_ns(task->real_parent, ns); 441 pgid = task_pgrp_nr_ns(task, ns); 442 443 unlock_task_sighand(task, &flags); 444 } 445 446 if (permitted && (!whole || num_threads < 2)) 447 wchan = get_wchan(task); 448 if (!whole) { 449 min_flt = task->min_flt; 450 maj_flt = task->maj_flt; 451 task_cputime_adjusted(task, &utime, &stime); 452 gtime = task_gtime(task); 453 } 454 455 /* scale priority and nice values from timeslices to -20..20 */ 456 /* to make it look like a "normal" Unix priority/nice value */ 457 priority = task_prio(task); 458 nice = task_nice(task); 459 460 /* convert nsec -> ticks */ 461 start_time = nsec_to_clock_t(task->real_start_time); 462 463 seq_printf(m, "%d (%s) %c", pid_nr_ns(pid, ns), tcomm, state); 464 seq_put_decimal_ll(m, ' ', ppid); 465 seq_put_decimal_ll(m, ' ', pgid); 466 seq_put_decimal_ll(m, ' ', sid); 467 seq_put_decimal_ll(m, ' ', tty_nr); 468 seq_put_decimal_ll(m, ' ', tty_pgrp); 469 seq_put_decimal_ull(m, ' ', task->flags); 470 seq_put_decimal_ull(m, ' ', min_flt); 471 seq_put_decimal_ull(m, ' ', cmin_flt); 472 seq_put_decimal_ull(m, ' ', maj_flt); 473 seq_put_decimal_ull(m, ' ', cmaj_flt); 474 seq_put_decimal_ull(m, ' ', cputime_to_clock_t(utime)); 475 seq_put_decimal_ull(m, ' ', cputime_to_clock_t(stime)); 476 seq_put_decimal_ll(m, ' ', cputime_to_clock_t(cutime)); 477 seq_put_decimal_ll(m, ' ', cputime_to_clock_t(cstime)); 478 seq_put_decimal_ll(m, ' ', priority); 479 seq_put_decimal_ll(m, ' ', nice); 480 seq_put_decimal_ll(m, ' ', num_threads); 481 seq_put_decimal_ull(m, ' ', 0); 482 seq_put_decimal_ull(m, ' ', start_time); 483 seq_put_decimal_ull(m, ' ', vsize); 484 seq_put_decimal_ull(m, ' ', mm ? get_mm_rss(mm) : 0); 485 seq_put_decimal_ull(m, ' ', rsslim); 486 seq_put_decimal_ull(m, ' ', mm ? (permitted ? mm->start_code : 1) : 0); 487 seq_put_decimal_ull(m, ' ', mm ? (permitted ? mm->end_code : 1) : 0); 488 seq_put_decimal_ull(m, ' ', (permitted && mm) ? mm->start_stack : 0); 489 seq_put_decimal_ull(m, ' ', esp); 490 seq_put_decimal_ull(m, ' ', eip); 491 /* The signal information here is obsolete. 492 * It must be decimal for Linux 2.0 compatibility. 493 * Use /proc/#/status for real-time signals. 494 */ 495 seq_put_decimal_ull(m, ' ', task->pending.signal.sig[0] & 0x7fffffffUL); 496 seq_put_decimal_ull(m, ' ', task->blocked.sig[0] & 0x7fffffffUL); 497 seq_put_decimal_ull(m, ' ', sigign.sig[0] & 0x7fffffffUL); 498 seq_put_decimal_ull(m, ' ', sigcatch.sig[0] & 0x7fffffffUL); 499 seq_put_decimal_ull(m, ' ', wchan); 500 seq_put_decimal_ull(m, ' ', 0); 501 seq_put_decimal_ull(m, ' ', 0); 502 seq_put_decimal_ll(m, ' ', task->exit_signal); 503 seq_put_decimal_ll(m, ' ', task_cpu(task)); 504 seq_put_decimal_ull(m, ' ', task->rt_priority); 505 seq_put_decimal_ull(m, ' ', task->policy); 506 seq_put_decimal_ull(m, ' ', delayacct_blkio_ticks(task)); 507 seq_put_decimal_ull(m, ' ', cputime_to_clock_t(gtime)); 508 seq_put_decimal_ll(m, ' ', cputime_to_clock_t(cgtime)); 509 510 if (mm && permitted) { 511 seq_put_decimal_ull(m, ' ', mm->start_data); 512 seq_put_decimal_ull(m, ' ', mm->end_data); 513 seq_put_decimal_ull(m, ' ', mm->start_brk); 514 seq_put_decimal_ull(m, ' ', mm->arg_start); 515 seq_put_decimal_ull(m, ' ', mm->arg_end); 516 seq_put_decimal_ull(m, ' ', mm->env_start); 517 seq_put_decimal_ull(m, ' ', mm->env_end); 518 } else 519 seq_printf(m, " 0 0 0 0 0 0 0"); 520 521 if (permitted) 522 seq_put_decimal_ll(m, ' ', task->exit_code); 523 else 524 seq_put_decimal_ll(m, ' ', 0); 525 526 seq_putc(m, '\n'); 527 if (mm) 528 mmput(mm); 529 return 0; 530 } 531 532 int proc_tid_stat(struct seq_file *m, struct pid_namespace *ns, 533 struct pid *pid, struct task_struct *task) 534 { 535 return do_task_stat(m, ns, pid, task, 0); 536 } 537 538 int proc_tgid_stat(struct seq_file *m, struct pid_namespace *ns, 539 struct pid *pid, struct task_struct *task) 540 { 541 return do_task_stat(m, ns, pid, task, 1); 542 } 543 544 int proc_pid_statm(struct seq_file *m, struct pid_namespace *ns, 545 struct pid *pid, struct task_struct *task) 546 { 547 unsigned long size = 0, resident = 0, shared = 0, text = 0, data = 0; 548 struct mm_struct *mm = get_task_mm(task); 549 550 if (mm) { 551 size = task_statm(mm, &shared, &text, &data, &resident); 552 mmput(mm); 553 } 554 /* 555 * For quick read, open code by putting numbers directly 556 * expected format is 557 * seq_printf(m, "%lu %lu %lu %lu 0 %lu 0\n", 558 * size, resident, shared, text, data); 559 */ 560 seq_put_decimal_ull(m, 0, size); 561 seq_put_decimal_ull(m, ' ', resident); 562 seq_put_decimal_ull(m, ' ', shared); 563 seq_put_decimal_ull(m, ' ', text); 564 seq_put_decimal_ull(m, ' ', 0); 565 seq_put_decimal_ull(m, ' ', data); 566 seq_put_decimal_ull(m, ' ', 0); 567 seq_putc(m, '\n'); 568 569 return 0; 570 } 571 572 #ifdef CONFIG_CHECKPOINT_RESTORE 573 static struct pid * 574 get_children_pid(struct inode *inode, struct pid *pid_prev, loff_t pos) 575 { 576 struct task_struct *start, *task; 577 struct pid *pid = NULL; 578 579 read_lock(&tasklist_lock); 580 581 start = pid_task(proc_pid(inode), PIDTYPE_PID); 582 if (!start) 583 goto out; 584 585 /* 586 * Lets try to continue searching first, this gives 587 * us significant speedup on children-rich processes. 588 */ 589 if (pid_prev) { 590 task = pid_task(pid_prev, PIDTYPE_PID); 591 if (task && task->real_parent == start && 592 !(list_empty(&task->sibling))) { 593 if (list_is_last(&task->sibling, &start->children)) 594 goto out; 595 task = list_first_entry(&task->sibling, 596 struct task_struct, sibling); 597 pid = get_pid(task_pid(task)); 598 goto out; 599 } 600 } 601 602 /* 603 * Slow search case. 604 * 605 * We might miss some children here if children 606 * are exited while we were not holding the lock, 607 * but it was never promised to be accurate that 608 * much. 609 * 610 * "Just suppose that the parent sleeps, but N children 611 * exit after we printed their tids. Now the slow paths 612 * skips N extra children, we miss N tasks." (c) 613 * 614 * So one need to stop or freeze the leader and all 615 * its children to get a precise result. 616 */ 617 list_for_each_entry(task, &start->children, sibling) { 618 if (pos-- == 0) { 619 pid = get_pid(task_pid(task)); 620 break; 621 } 622 } 623 624 out: 625 read_unlock(&tasklist_lock); 626 return pid; 627 } 628 629 static int children_seq_show(struct seq_file *seq, void *v) 630 { 631 struct inode *inode = seq->private; 632 pid_t pid; 633 634 pid = pid_nr_ns(v, inode->i_sb->s_fs_info); 635 seq_printf(seq, "%d ", pid); 636 637 return 0; 638 } 639 640 static void *children_seq_start(struct seq_file *seq, loff_t *pos) 641 { 642 return get_children_pid(seq->private, NULL, *pos); 643 } 644 645 static void *children_seq_next(struct seq_file *seq, void *v, loff_t *pos) 646 { 647 struct pid *pid; 648 649 pid = get_children_pid(seq->private, v, *pos + 1); 650 put_pid(v); 651 652 ++*pos; 653 return pid; 654 } 655 656 static void children_seq_stop(struct seq_file *seq, void *v) 657 { 658 put_pid(v); 659 } 660 661 static const struct seq_operations children_seq_ops = { 662 .start = children_seq_start, 663 .next = children_seq_next, 664 .stop = children_seq_stop, 665 .show = children_seq_show, 666 }; 667 668 static int children_seq_open(struct inode *inode, struct file *file) 669 { 670 struct seq_file *m; 671 int ret; 672 673 ret = seq_open(file, &children_seq_ops); 674 if (ret) 675 return ret; 676 677 m = file->private_data; 678 m->private = inode; 679 680 return ret; 681 } 682 683 int children_seq_release(struct inode *inode, struct file *file) 684 { 685 seq_release(inode, file); 686 return 0; 687 } 688 689 const struct file_operations proc_tid_children_operations = { 690 .open = children_seq_open, 691 .read = seq_read, 692 .llseek = seq_lseek, 693 .release = children_seq_release, 694 }; 695 #endif /* CONFIG_CHECKPOINT_RESTORE */ 696