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Linux 4.2.6
[linux/fpc-iii.git] / fs / proc / array.c
blobce065cf3104fb5ddd042a6c1344936d0ef0e8184
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 /*
130 * Parked tasks do not run; they sit in __kthread_parkme().
131 * Without this check, we would report them as running, which is
132 * clearly wrong, so we report them as sleeping instead.
133 */
134 if (tsk->state == TASK_PARKED)
135 state = TASK_INTERRUPTIBLE;
136
137 BUILD_BUG_ON(1 + ilog2(TASK_REPORT) != ARRAY_SIZE(task_state_array)-1);
138
139 return task_state_array[fls(state)];
140 }
141
142 static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
143 struct pid *pid, struct task_struct *p)
144 {
145 struct user_namespace *user_ns = seq_user_ns(m);
146 struct group_info *group_info;
147 int g;
148 struct task_struct *tracer;
149 const struct cred *cred;
150 pid_t ppid, tpid = 0, tgid, ngid;
151 unsigned int max_fds = 0;
152
153 rcu_read_lock();
154 ppid = pid_alive(p) ?
155 task_tgid_nr_ns(rcu_dereference(p->real_parent), ns) : 0;
156
157 tracer = ptrace_parent(p);
158 if (tracer)
159 tpid = task_pid_nr_ns(tracer, ns);
160
161 tgid = task_tgid_nr_ns(p, ns);
162 ngid = task_numa_group_id(p);
163 cred = get_task_cred(p);
164
165 task_lock(p);
166 if (p->files)
167 max_fds = files_fdtable(p->files)->max_fds;
168 task_unlock(p);
169 rcu_read_unlock();
170
171 seq_printf(m,
172 "State:\t%s\n"
173 "Tgid:\t%d\n"
174 "Ngid:\t%d\n"
175 "Pid:\t%d\n"
176 "PPid:\t%d\n"
177 "TracerPid:\t%d\n"
178 "Uid:\t%d\t%d\t%d\t%d\n"
179 "Gid:\t%d\t%d\t%d\t%d\n"
180 "FDSize:\t%d\nGroups:\t",
181 get_task_state(p),
182 tgid, ngid, pid_nr_ns(pid, ns), ppid, tpid,
183 from_kuid_munged(user_ns, cred->uid),
184 from_kuid_munged(user_ns, cred->euid),
185 from_kuid_munged(user_ns, cred->suid),
186 from_kuid_munged(user_ns, cred->fsuid),
187 from_kgid_munged(user_ns, cred->gid),
188 from_kgid_munged(user_ns, cred->egid),
189 from_kgid_munged(user_ns, cred->sgid),
190 from_kgid_munged(user_ns, cred->fsgid),
191 max_fds);
192
193 group_info = cred->group_info;
194 for (g = 0; g < group_info->ngroups; g++)
195 seq_printf(m, "%d ",
196 from_kgid_munged(user_ns, GROUP_AT(group_info, g)));
197 put_cred(cred);
198
199 #ifdef CONFIG_PID_NS
200 seq_puts(m, "\nNStgid:");
201 for (g = ns->level; g <= pid->level; g++)
202 seq_printf(m, "\t%d",
203 task_tgid_nr_ns(p, pid->numbers[g].ns));
204 seq_puts(m, "\nNSpid:");
205 for (g = ns->level; g <= pid->level; g++)
206 seq_printf(m, "\t%d",
207 task_pid_nr_ns(p, pid->numbers[g].ns));
208 seq_puts(m, "\nNSpgid:");
209 for (g = ns->level; g <= pid->level; g++)
210 seq_printf(m, "\t%d",
211 task_pgrp_nr_ns(p, pid->numbers[g].ns));
212 seq_puts(m, "\nNSsid:");
213 for (g = ns->level; g <= pid->level; g++)
214 seq_printf(m, "\t%d",
215 task_session_nr_ns(p, pid->numbers[g].ns));
216 #endif
217 seq_putc(m, '\n');
218 }
219
220 void render_sigset_t(struct seq_file *m, const char *header,
221 sigset_t *set)
222 {
223 int i;
224
225 seq_puts(m, header);
226
227 i = _NSIG;
228 do {
229 int x = 0;
230
231 i -= 4;
232 if (sigismember(set, i+1)) x |= 1;
233 if (sigismember(set, i+2)) x |= 2;
234 if (sigismember(set, i+3)) x |= 4;
235 if (sigismember(set, i+4)) x |= 8;
236 seq_printf(m, "%x", x);
237 } while (i >= 4);
238
239 seq_putc(m, '\n');
240 }
241
242 static void collect_sigign_sigcatch(struct task_struct *p, sigset_t *ign,
243 sigset_t *catch)
244 {
245 struct k_sigaction *k;
246 int i;
247
248 k = p->sighand->action;
249 for (i = 1; i <= _NSIG; ++i, ++k) {
250 if (k->sa.sa_handler == SIG_IGN)
251 sigaddset(ign, i);
252 else if (k->sa.sa_handler != SIG_DFL)
253 sigaddset(catch, i);
254 }
255 }
256
257 static inline void task_sig(struct seq_file *m, struct task_struct *p)
258 {
259 unsigned long flags;
260 sigset_t pending, shpending, blocked, ignored, caught;
261 int num_threads = 0;
262 unsigned long qsize = 0;
263 unsigned long qlim = 0;
264
265 sigemptyset(&pending);
266 sigemptyset(&shpending);
267 sigemptyset(&blocked);
268 sigemptyset(&ignored);
269 sigemptyset(&caught);
270
271 if (lock_task_sighand(p, &flags)) {
272 pending = p->pending.signal;
273 shpending = p->signal->shared_pending.signal;
274 blocked = p->blocked;
275 collect_sigign_sigcatch(p, &ignored, &caught);
276 num_threads = get_nr_threads(p);
277 rcu_read_lock(); /* FIXME: is this correct? */
278 qsize = atomic_read(&__task_cred(p)->user->sigpending);
279 rcu_read_unlock();
280 qlim = task_rlimit(p, RLIMIT_SIGPENDING);
281 unlock_task_sighand(p, &flags);
282 }
283
284 seq_printf(m, "Threads:\t%d\n", num_threads);
285 seq_printf(m, "SigQ:\t%lu/%lu\n", qsize, qlim);
286
287 /* render them all */
288 render_sigset_t(m, "SigPnd:\t", &pending);
289 render_sigset_t(m, "ShdPnd:\t", &shpending);
290 render_sigset_t(m, "SigBlk:\t", &blocked);
291 render_sigset_t(m, "SigIgn:\t", &ignored);
292 render_sigset_t(m, "SigCgt:\t", &caught);
293 }
294
295 static void render_cap_t(struct seq_file *m, const char *header,
296 kernel_cap_t *a)
297 {
298 unsigned __capi;
299
300 seq_puts(m, header);
301 CAP_FOR_EACH_U32(__capi) {
302 seq_printf(m, "%08x",
303 a->cap[CAP_LAST_U32 - __capi]);
304 }
305 seq_putc(m, '\n');
306 }
307
308 static inline void task_cap(struct seq_file *m, struct task_struct *p)
309 {
310 const struct cred *cred;
311 kernel_cap_t cap_inheritable, cap_permitted, cap_effective, cap_bset;
312
313 rcu_read_lock();
314 cred = __task_cred(p);
315 cap_inheritable = cred->cap_inheritable;
316 cap_permitted = cred->cap_permitted;
317 cap_effective = cred->cap_effective;
318 cap_bset = cred->cap_bset;
319 rcu_read_unlock();
320
321 render_cap_t(m, "CapInh:\t", &cap_inheritable);
322 render_cap_t(m, "CapPrm:\t", &cap_permitted);
323 render_cap_t(m, "CapEff:\t", &cap_effective);
324 render_cap_t(m, "CapBnd:\t", &cap_bset);
325 }
326
327 static inline void task_seccomp(struct seq_file *m, struct task_struct *p)
328 {
329 #ifdef CONFIG_SECCOMP
330 seq_printf(m, "Seccomp:\t%d\n", p->seccomp.mode);
331 #endif
332 }
333
334 static inline void task_context_switch_counts(struct seq_file *m,
335 struct task_struct *p)
336 {
337 seq_printf(m, "voluntary_ctxt_switches:\t%lu\n"
338 "nonvoluntary_ctxt_switches:\t%lu\n",
339 p->nvcsw,
340 p->nivcsw);
341 }
342
343 static void task_cpus_allowed(struct seq_file *m, struct task_struct *task)
344 {
345 seq_printf(m, "Cpus_allowed:\t%*pb\n",
346 cpumask_pr_args(&task->cpus_allowed));
347 seq_printf(m, "Cpus_allowed_list:\t%*pbl\n",
348 cpumask_pr_args(&task->cpus_allowed));
349 }
350
351 int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
352 struct pid *pid, struct task_struct *task)
353 {
354 struct mm_struct *mm = get_task_mm(task);
355
356 task_name(m, task);
357 task_state(m, ns, pid, task);
358
359 if (mm) {
360 task_mem(m, mm);
361 mmput(mm);
362 }
363 task_sig(m, task);
364 task_cap(m, task);
365 task_seccomp(m, task);
366 task_cpus_allowed(m, task);
367 cpuset_task_status_allowed(m, task);
368 task_context_switch_counts(m, task);
369 return 0;
370 }
371
372 static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
373 struct pid *pid, struct task_struct *task, int whole)
374 {
375 unsigned long vsize, eip, esp, wchan = ~0UL;
376 int priority, nice;
377 int tty_pgrp = -1, tty_nr = 0;
378 sigset_t sigign, sigcatch;
379 char state;
380 pid_t ppid = 0, pgid = -1, sid = -1;
381 int num_threads = 0;
382 int permitted;
383 struct mm_struct *mm;
384 unsigned long long start_time;
385 unsigned long cmin_flt = 0, cmaj_flt = 0;
386 unsigned long min_flt = 0, maj_flt = 0;
387 cputime_t cutime, cstime, utime, stime;
388 cputime_t cgtime, gtime;
389 unsigned long rsslim = 0;
390 char tcomm[sizeof(task->comm)];
391 unsigned long flags;
392
393 state = *get_task_state(task);
394 vsize = eip = esp = 0;
395 permitted = ptrace_may_access(task, PTRACE_MODE_READ | PTRACE_MODE_NOAUDIT);
396 mm = get_task_mm(task);
397 if (mm) {
398 vsize = task_vsize(mm);
399 if (permitted) {
400 eip = KSTK_EIP(task);
401 esp = KSTK_ESP(task);
402 }
403 }
404
405 get_task_comm(tcomm, task);
406
407 sigemptyset(&sigign);
408 sigemptyset(&sigcatch);
409 cutime = cstime = utime = stime = 0;
410 cgtime = gtime = 0;
411
412 if (lock_task_sighand(task, &flags)) {
413 struct signal_struct *sig = task->signal;
414
415 if (sig->tty) {
416 struct pid *pgrp = tty_get_pgrp(sig->tty);
417 tty_pgrp = pid_nr_ns(pgrp, ns);
418 put_pid(pgrp);
419 tty_nr = new_encode_dev(tty_devnum(sig->tty));
420 }
421
422 num_threads = get_nr_threads(task);
423 collect_sigign_sigcatch(task, &sigign, &sigcatch);
424
425 cmin_flt = sig->cmin_flt;
426 cmaj_flt = sig->cmaj_flt;
427 cutime = sig->cutime;
428 cstime = sig->cstime;
429 cgtime = sig->cgtime;
430 rsslim = ACCESS_ONCE(sig->rlim[RLIMIT_RSS].rlim_cur);
431
432 /* add up live thread stats at the group level */
433 if (whole) {
434 struct task_struct *t = task;
435 do {
436 min_flt += t->min_flt;
437 maj_flt += t->maj_flt;
438 gtime += task_gtime(t);
439 } while_each_thread(task, t);
440
441 min_flt += sig->min_flt;
442 maj_flt += sig->maj_flt;
443 thread_group_cputime_adjusted(task, &utime, &stime);
444 gtime += sig->gtime;
445 }
446
447 sid = task_session_nr_ns(task, ns);
448 ppid = task_tgid_nr_ns(task->real_parent, ns);
449 pgid = task_pgrp_nr_ns(task, ns);
450
451 unlock_task_sighand(task, &flags);
452 }
453
454 if (permitted && (!whole || num_threads < 2))
455 wchan = get_wchan(task);
456 if (!whole) {
457 min_flt = task->min_flt;
458 maj_flt = task->maj_flt;
459 task_cputime_adjusted(task, &utime, &stime);
460 gtime = task_gtime(task);
461 }
462
463 /* scale priority and nice values from timeslices to -20..20 */
464 /* to make it look like a "normal" Unix priority/nice value */
465 priority = task_prio(task);
466 nice = task_nice(task);
467
468 /* convert nsec -> ticks */
469 start_time = nsec_to_clock_t(task->real_start_time);
470
471 seq_printf(m, "%d (%s) %c", pid_nr_ns(pid, ns), tcomm, state);
472 seq_put_decimal_ll(m, ' ', ppid);
473 seq_put_decimal_ll(m, ' ', pgid);
474 seq_put_decimal_ll(m, ' ', sid);
475 seq_put_decimal_ll(m, ' ', tty_nr);
476 seq_put_decimal_ll(m, ' ', tty_pgrp);
477 seq_put_decimal_ull(m, ' ', task->flags);
478 seq_put_decimal_ull(m, ' ', min_flt);
479 seq_put_decimal_ull(m, ' ', cmin_flt);
480 seq_put_decimal_ull(m, ' ', maj_flt);
481 seq_put_decimal_ull(m, ' ', cmaj_flt);
482 seq_put_decimal_ull(m, ' ', cputime_to_clock_t(utime));
483 seq_put_decimal_ull(m, ' ', cputime_to_clock_t(stime));
484 seq_put_decimal_ll(m, ' ', cputime_to_clock_t(cutime));
485 seq_put_decimal_ll(m, ' ', cputime_to_clock_t(cstime));
486 seq_put_decimal_ll(m, ' ', priority);
487 seq_put_decimal_ll(m, ' ', nice);
488 seq_put_decimal_ll(m, ' ', num_threads);
489 seq_put_decimal_ull(m, ' ', 0);
490 seq_put_decimal_ull(m, ' ', start_time);
491 seq_put_decimal_ull(m, ' ', vsize);
492 seq_put_decimal_ull(m, ' ', mm ? get_mm_rss(mm) : 0);
493 seq_put_decimal_ull(m, ' ', rsslim);
494 seq_put_decimal_ull(m, ' ', mm ? (permitted ? mm->start_code : 1) : 0);
495 seq_put_decimal_ull(m, ' ', mm ? (permitted ? mm->end_code : 1) : 0);
496 seq_put_decimal_ull(m, ' ', (permitted && mm) ? mm->start_stack : 0);
497 seq_put_decimal_ull(m, ' ', esp);
498 seq_put_decimal_ull(m, ' ', eip);
499 /* The signal information here is obsolete.
500 * It must be decimal for Linux 2.0 compatibility.
501 * Use /proc/#/status for real-time signals.
502 */
503 seq_put_decimal_ull(m, ' ', task->pending.signal.sig[0] & 0x7fffffffUL);
504 seq_put_decimal_ull(m, ' ', task->blocked.sig[0] & 0x7fffffffUL);
505 seq_put_decimal_ull(m, ' ', sigign.sig[0] & 0x7fffffffUL);
506 seq_put_decimal_ull(m, ' ', sigcatch.sig[0] & 0x7fffffffUL);
507 seq_put_decimal_ull(m, ' ', wchan);
508 seq_put_decimal_ull(m, ' ', 0);
509 seq_put_decimal_ull(m, ' ', 0);
510 seq_put_decimal_ll(m, ' ', task->exit_signal);
511 seq_put_decimal_ll(m, ' ', task_cpu(task));
512 seq_put_decimal_ull(m, ' ', task->rt_priority);
513 seq_put_decimal_ull(m, ' ', task->policy);
514 seq_put_decimal_ull(m, ' ', delayacct_blkio_ticks(task));
515 seq_put_decimal_ull(m, ' ', cputime_to_clock_t(gtime));
516 seq_put_decimal_ll(m, ' ', cputime_to_clock_t(cgtime));
517
518 if (mm && permitted) {
519 seq_put_decimal_ull(m, ' ', mm->start_data);
520 seq_put_decimal_ull(m, ' ', mm->end_data);
521 seq_put_decimal_ull(m, ' ', mm->start_brk);
522 seq_put_decimal_ull(m, ' ', mm->arg_start);
523 seq_put_decimal_ull(m, ' ', mm->arg_end);
524 seq_put_decimal_ull(m, ' ', mm->env_start);
525 seq_put_decimal_ull(m, ' ', mm->env_end);
526 } else
527 seq_printf(m, " 0 0 0 0 0 0 0");
528
529 if (permitted)
530 seq_put_decimal_ll(m, ' ', task->exit_code);
531 else
532 seq_put_decimal_ll(m, ' ', 0);
533
534 seq_putc(m, '\n');
535 if (mm)
536 mmput(mm);
537 return 0;
538 }
539
540 int proc_tid_stat(struct seq_file *m, struct pid_namespace *ns,
541 struct pid *pid, struct task_struct *task)
542 {
543 return do_task_stat(m, ns, pid, task, 0);
544 }
545
546 int proc_tgid_stat(struct seq_file *m, struct pid_namespace *ns,
547 struct pid *pid, struct task_struct *task)
548 {
549 return do_task_stat(m, ns, pid, task, 1);
550 }
551
552 int proc_pid_statm(struct seq_file *m, struct pid_namespace *ns,
553 struct pid *pid, struct task_struct *task)
554 {
555 unsigned long size = 0, resident = 0, shared = 0, text = 0, data = 0;
556 struct mm_struct *mm = get_task_mm(task);
557
558 if (mm) {
559 size = task_statm(mm, &shared, &text, &data, &resident);
560 mmput(mm);
561 }
562 /*
563 * For quick read, open code by putting numbers directly
564 * expected format is
565 * seq_printf(m, "%lu %lu %lu %lu 0 %lu 0\n",
566 * size, resident, shared, text, data);
567 */
568 seq_put_decimal_ull(m, 0, size);
569 seq_put_decimal_ull(m, ' ', resident);
570 seq_put_decimal_ull(m, ' ', shared);
571 seq_put_decimal_ull(m, ' ', text);
572 seq_put_decimal_ull(m, ' ', 0);
573 seq_put_decimal_ull(m, ' ', data);
574 seq_put_decimal_ull(m, ' ', 0);
575 seq_putc(m, '\n');
576
577 return 0;
578 }
579
580 #ifdef CONFIG_PROC_CHILDREN
581 static struct pid *
582 get_children_pid(struct inode *inode, struct pid *pid_prev, loff_t pos)
583 {
584 struct task_struct *start, *task;
585 struct pid *pid = NULL;
586
587 read_lock(&tasklist_lock);
588
589 start = pid_task(proc_pid(inode), PIDTYPE_PID);
590 if (!start)
591 goto out;
592
593 /*
594 * Lets try to continue searching first, this gives
595 * us significant speedup on children-rich processes.
596 */
597 if (pid_prev) {
598 task = pid_task(pid_prev, PIDTYPE_PID);
599 if (task && task->real_parent == start &&
600 !(list_empty(&task->sibling))) {
601 if (list_is_last(&task->sibling, &start->children))
602 goto out;
603 task = list_first_entry(&task->sibling,
604 struct task_struct, sibling);
605 pid = get_pid(task_pid(task));
606 goto out;
607 }
608 }
609
610 /*
611 * Slow search case.
612 *
613 * We might miss some children here if children
614 * are exited while we were not holding the lock,
615 * but it was never promised to be accurate that
616 * much.
617 *
618 * "Just suppose that the parent sleeps, but N children
619 * exit after we printed their tids. Now the slow paths
620 * skips N extra children, we miss N tasks." (c)
621 *
622 * So one need to stop or freeze the leader and all
623 * its children to get a precise result.
624 */
625 list_for_each_entry(task, &start->children, sibling) {
626 if (pos-- == 0) {
627 pid = get_pid(task_pid(task));
628 break;
629 }
630 }
631
632 out:
633 read_unlock(&tasklist_lock);
634 return pid;
635 }
636
637 static int children_seq_show(struct seq_file *seq, void *v)
638 {
639 struct inode *inode = seq->private;
640 pid_t pid;
641
642 pid = pid_nr_ns(v, inode->i_sb->s_fs_info);
643 seq_printf(seq, "%d ", pid);
644
645 return 0;
646 }
647
648 static void *children_seq_start(struct seq_file *seq, loff_t *pos)
649 {
650 return get_children_pid(seq->private, NULL, *pos);
651 }
652
653 static void *children_seq_next(struct seq_file *seq, void *v, loff_t *pos)
654 {
655 struct pid *pid;
656
657 pid = get_children_pid(seq->private, v, *pos + 1);
658 put_pid(v);
659
660 ++*pos;
661 return pid;
662 }
663
664 static void children_seq_stop(struct seq_file *seq, void *v)
665 {
666 put_pid(v);
667 }
668
669 static const struct seq_operations children_seq_ops = {
670 .start = children_seq_start,
671 .next = children_seq_next,
672 .stop = children_seq_stop,
673 .show = children_seq_show,
674 };
675
676 static int children_seq_open(struct inode *inode, struct file *file)
677 {
678 struct seq_file *m;
679 int ret;
680
681 ret = seq_open(file, &children_seq_ops);
682 if (ret)
683 return ret;
684
685 m = file->private_data;
686 m->private = inode;
687
688 return ret;
689 }
690
691 int children_seq_release(struct inode *inode, struct file *file)
692 {
693 seq_release(inode, file);
694 return 0;
695 }
696
697 const struct file_operations proc_tid_children_operations = {
698 .open = children_seq_open,
699 .read = seq_read,
700 .llseek = seq_lseek,
701 .release = children_seq_release,
702 };
703 #endif /* CONFIG_PROC_CHILDREN */
Linux with added FPC-III support