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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#include <linux/fs_struct.h>
87
88#include <asm/pgtable.h>
89#include <asm/processor.h>
90#include "internal.h"
91
92static inline void task_name(struct seq_file *m, struct task_struct *p)
93{
94 char *buf;
95 size_t size;
96 char tcomm[sizeof(p->comm)];
97 int ret;
98
99 get_task_comm(tcomm, p);
100
101 seq_puts(m, "Name:\t");
102
103 size = seq_get_buf(m, &buf);
104 ret = string_escape_str(tcomm, buf, size, ESCAPE_SPACE | ESCAPE_SPECIAL, "\n\\");
105 seq_commit(m, ret < size ? ret : -1);
106
107 seq_putc(m, '\n');
108}
109
110/*
111 * The task state array is a strange "bitmap" of
112 * reasons to sleep. Thus "running" is zero, and
113 * you can test for combinations of others with
114 * simple bit tests.
115 */
116static const char * const task_state_array[] = {
117 "R (running)", /* 0 */
118 "S (sleeping)", /* 1 */
119 "D (disk sleep)", /* 2 */
120 "T (stopped)", /* 4 */
121 "t (tracing stop)", /* 8 */
122 "X (dead)", /* 16 */
123 "Z (zombie)", /* 32 */
124};
125
126static inline const char *get_task_state(struct task_struct *tsk)
127{
128 unsigned int state = (tsk->state | tsk->exit_state) & TASK_REPORT;
129
130 /*
131 * Parked tasks do not run; they sit in __kthread_parkme().
132 * Without this check, we would report them as running, which is
133 * clearly wrong, so we report them as sleeping instead.
134 */
135 if (tsk->state == TASK_PARKED)
136 state = TASK_INTERRUPTIBLE;
137
138 BUILD_BUG_ON(1 + ilog2(TASK_REPORT) != ARRAY_SIZE(task_state_array)-1);
139
140 return task_state_array[fls(state)];
141}
142
143static inline int get_task_umask(struct task_struct *tsk)
144{
145 struct fs_struct *fs;
146 int umask = -ENOENT;
147
148 task_lock(tsk);
149 fs = tsk->fs;
150 if (fs)
151 umask = fs->umask;
152 task_unlock(tsk);
153 return umask;
154}
155
156static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
157 struct pid *pid, struct task_struct *p)
158{
159 struct user_namespace *user_ns = seq_user_ns(m);
160 struct group_info *group_info;
161 int g, umask;
162 struct task_struct *tracer;
163 const struct cred *cred;
164 pid_t ppid, tpid = 0, tgid, ngid;
165 unsigned int max_fds = 0;
166
167 rcu_read_lock();
168 ppid = pid_alive(p) ?
169 task_tgid_nr_ns(rcu_dereference(p->real_parent), ns) : 0;
170
171 tracer = ptrace_parent(p);
172 if (tracer)
173 tpid = task_pid_nr_ns(tracer, ns);
174
175 tgid = task_tgid_nr_ns(p, ns);
176 ngid = task_numa_group_id(p);
177 cred = get_task_cred(p);
178
179 umask = get_task_umask(p);
180 if (umask >= 0)
181 seq_printf(m, "Umask:\t%#04o\n", umask);
182
183 task_lock(p);
184 if (p->files)
185 max_fds = files_fdtable(p->files)->max_fds;
186 task_unlock(p);
187 rcu_read_unlock();
188
189 seq_printf(m, "State:\t%s", get_task_state(p));
190
191 seq_put_decimal_ull(m, "\nTgid:\t", tgid);
192 seq_put_decimal_ull(m, "\nNgid:\t", ngid);
193 seq_put_decimal_ull(m, "\nPid:\t", pid_nr_ns(pid, ns));
194 seq_put_decimal_ull(m, "\nPPid:\t", ppid);
195 seq_put_decimal_ull(m, "\nTracerPid:\t", tpid);
196 seq_put_decimal_ull(m, "\nUid:\t", from_kuid_munged(user_ns, cred->uid));
197 seq_put_decimal_ull(m, "\t", from_kuid_munged(user_ns, cred->euid));
198 seq_put_decimal_ull(m, "\t", from_kuid_munged(user_ns, cred->suid));
199 seq_put_decimal_ull(m, "\t", from_kuid_munged(user_ns, cred->fsuid));
200 seq_put_decimal_ull(m, "\nGid:\t", from_kgid_munged(user_ns, cred->gid));
201 seq_put_decimal_ull(m, "\t", from_kgid_munged(user_ns, cred->egid));
202 seq_put_decimal_ull(m, "\t", from_kgid_munged(user_ns, cred->sgid));
203 seq_put_decimal_ull(m, "\t", from_kgid_munged(user_ns, cred->fsgid));
204 seq_put_decimal_ull(m, "\nFDSize:\t", max_fds);
205
206 seq_puts(m, "\nGroups:\t");
207 group_info = cred->group_info;
208 for (g = 0; g < group_info->ngroups; g++)
209 seq_put_decimal_ull(m, g ? " " : "",
210 from_kgid_munged(user_ns, group_info->gid[g]));
211 put_cred(cred);
212 /* Trailing space shouldn't have been added in the first place. */
213 seq_putc(m, ' ');
214
215#ifdef CONFIG_PID_NS
216 seq_puts(m, "\nNStgid:");
217 for (g = ns->level; g <= pid->level; g++)
218 seq_put_decimal_ull(m, "\t", task_tgid_nr_ns(p, pid->numbers[g].ns));
219 seq_puts(m, "\nNSpid:");
220 for (g = ns->level; g <= pid->level; g++)
221 seq_put_decimal_ull(m, "\t", task_pid_nr_ns(p, pid->numbers[g].ns));
222 seq_puts(m, "\nNSpgid:");
223 for (g = ns->level; g <= pid->level; g++)
224 seq_put_decimal_ull(m, "\t", task_pgrp_nr_ns(p, pid->numbers[g].ns));
225 seq_puts(m, "\nNSsid:");
226 for (g = ns->level; g <= pid->level; g++)
227 seq_put_decimal_ull(m, "\t", task_session_nr_ns(p, pid->numbers[g].ns));
228#endif
229 seq_putc(m, '\n');
230}
231
232void render_sigset_t(struct seq_file *m, const char *header,
233 sigset_t *set)
234{
235 int i;
236
237 seq_puts(m, header);
238
239 i = _NSIG;
240 do {
241 int x = 0;
242
243 i -= 4;
244 if (sigismember(set, i+1)) x |= 1;
245 if (sigismember(set, i+2)) x |= 2;
246 if (sigismember(set, i+3)) x |= 4;
247 if (sigismember(set, i+4)) x |= 8;
248 seq_putc(m, hex_asc[x]);
249 } while (i >= 4);
250
251 seq_putc(m, '\n');
252}
253
254static void collect_sigign_sigcatch(struct task_struct *p, sigset_t *ign,
255 sigset_t *catch)
256{
257 struct k_sigaction *k;
258 int i;
259
260 k = p->sighand->action;
261 for (i = 1; i <= _NSIG; ++i, ++k) {
262 if (k->sa.sa_handler == SIG_IGN)
263 sigaddset(ign, i);
264 else if (k->sa.sa_handler != SIG_DFL)
265 sigaddset(catch, i);
266 }
267}
268
269static inline void task_sig(struct seq_file *m, struct task_struct *p)
270{
271 unsigned long flags;
272 sigset_t pending, shpending, blocked, ignored, caught;
273 int num_threads = 0;
274 unsigned long qsize = 0;
275 unsigned long qlim = 0;
276
277 sigemptyset(&pending);
278 sigemptyset(&shpending);
279 sigemptyset(&blocked);
280 sigemptyset(&ignored);
281 sigemptyset(&caught);
282
283 if (lock_task_sighand(p, &flags)) {
284 pending = p->pending.signal;
285 shpending = p->signal->shared_pending.signal;
286 blocked = p->blocked;
287 collect_sigign_sigcatch(p, &ignored, &caught);
288 num_threads = get_nr_threads(p);
289 rcu_read_lock(); /* FIXME: is this correct? */
290 qsize = atomic_read(&__task_cred(p)->user->sigpending);
291 rcu_read_unlock();
292 qlim = task_rlimit(p, RLIMIT_SIGPENDING);
293 unlock_task_sighand(p, &flags);
294 }
295
296 seq_put_decimal_ull(m, "Threads:\t", num_threads);
297 seq_put_decimal_ull(m, "\nSigQ:\t", qsize);
298 seq_put_decimal_ull(m, "/", qlim);
299
300 /* render them all */
301 render_sigset_t(m, "\nSigPnd:\t", &pending);
302 render_sigset_t(m, "ShdPnd:\t", &shpending);
303 render_sigset_t(m, "SigBlk:\t", &blocked);
304 render_sigset_t(m, "SigIgn:\t", &ignored);
305 render_sigset_t(m, "SigCgt:\t", &caught);
306}
307
308static void render_cap_t(struct seq_file *m, const char *header,
309 kernel_cap_t *a)
310{
311 unsigned __capi;
312
313 seq_puts(m, header);
314 CAP_FOR_EACH_U32(__capi) {
315 seq_printf(m, "%08x",
316 a->cap[CAP_LAST_U32 - __capi]);
317 }
318 seq_putc(m, '\n');
319}
320
321static inline void task_cap(struct seq_file *m, struct task_struct *p)
322{
323 const struct cred *cred;
324 kernel_cap_t cap_inheritable, cap_permitted, cap_effective,
325 cap_bset, cap_ambient;
326
327 rcu_read_lock();
328 cred = __task_cred(p);
329 cap_inheritable = cred->cap_inheritable;
330 cap_permitted = cred->cap_permitted;
331 cap_effective = cred->cap_effective;
332 cap_bset = cred->cap_bset;
333 cap_ambient = cred->cap_ambient;
334 rcu_read_unlock();
335
336 render_cap_t(m, "CapInh:\t", &cap_inheritable);
337 render_cap_t(m, "CapPrm:\t", &cap_permitted);
338 render_cap_t(m, "CapEff:\t", &cap_effective);
339 render_cap_t(m, "CapBnd:\t", &cap_bset);
340 render_cap_t(m, "CapAmb:\t", &cap_ambient);
341}
342
343static inline void task_seccomp(struct seq_file *m, struct task_struct *p)
344{
345 seq_put_decimal_ull(m, "NoNewPrivs:\t", task_no_new_privs(p));
346#ifdef CONFIG_SECCOMP
347 seq_put_decimal_ull(m, "\nSeccomp:\t", p->seccomp.mode);
348#endif
349 seq_putc(m, '\n');
350}
351
352static inline void task_context_switch_counts(struct seq_file *m,
353 struct task_struct *p)
354{
355 seq_put_decimal_ull(m, "voluntary_ctxt_switches:\t", p->nvcsw);
356 seq_put_decimal_ull(m, "\nnonvoluntary_ctxt_switches:\t", p->nivcsw);
357 seq_putc(m, '\n');
358}
359
360static void task_cpus_allowed(struct seq_file *m, struct task_struct *task)
361{
362 seq_printf(m, "Cpus_allowed:\t%*pb\n",
363 cpumask_pr_args(&task->cpus_allowed));
364 seq_printf(m, "Cpus_allowed_list:\t%*pbl\n",
365 cpumask_pr_args(&task->cpus_allowed));
366}
367
368int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
369 struct pid *pid, struct task_struct *task)
370{
371 struct mm_struct *mm = get_task_mm(task);
372
373 task_name(m, task);
374 task_state(m, ns, pid, task);
375
376 if (mm) {
377 task_mem(m, mm);
378 mmput(mm);
379 }
380 task_sig(m, task);
381 task_cap(m, task);
382 task_seccomp(m, task);
383 task_cpus_allowed(m, task);
384 cpuset_task_status_allowed(m, task);
385 task_context_switch_counts(m, task);
386 return 0;
387}
388
389static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
390 struct pid *pid, struct task_struct *task, int whole)
391{
392 unsigned long vsize, eip, esp, wchan = 0;
393 int priority, nice;
394 int tty_pgrp = -1, tty_nr = 0;
395 sigset_t sigign, sigcatch;
396 char state;
397 pid_t ppid = 0, pgid = -1, sid = -1;
398 int num_threads = 0;
399 int permitted;
400 struct mm_struct *mm;
401 unsigned long long start_time;
402 unsigned long cmin_flt = 0, cmaj_flt = 0;
403 unsigned long min_flt = 0, maj_flt = 0;
404 cputime_t cutime, cstime, utime, stime;
405 cputime_t cgtime, gtime;
406 unsigned long rsslim = 0;
407 char tcomm[sizeof(task->comm)];
408 unsigned long flags;
409
410 state = *get_task_state(task);
411 vsize = eip = esp = 0;
412 permitted = ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS | PTRACE_MODE_NOAUDIT);
413 mm = get_task_mm(task);
414 if (mm) {
415 vsize = task_vsize(mm);
416 /*
417 * esp and eip are intentionally zeroed out. There is no
418 * non-racy way to read them without freezing the task.
419 * Programs that need reliable values can use ptrace(2).
420 */
421 }
422
423 get_task_comm(tcomm, task);
424
425 sigemptyset(&sigign);
426 sigemptyset(&sigcatch);
427 cutime = cstime = utime = stime = 0;
428 cgtime = gtime = 0;
429
430 if (lock_task_sighand(task, &flags)) {
431 struct signal_struct *sig = task->signal;
432
433 if (sig->tty) {
434 struct pid *pgrp = tty_get_pgrp(sig->tty);
435 tty_pgrp = pid_nr_ns(pgrp, ns);
436 put_pid(pgrp);
437 tty_nr = new_encode_dev(tty_devnum(sig->tty));
438 }
439
440 num_threads = get_nr_threads(task);
441 collect_sigign_sigcatch(task, &sigign, &sigcatch);
442
443 cmin_flt = sig->cmin_flt;
444 cmaj_flt = sig->cmaj_flt;
445 cutime = sig->cutime;
446 cstime = sig->cstime;
447 cgtime = sig->cgtime;
448 rsslim = ACCESS_ONCE(sig->rlim[RLIMIT_RSS].rlim_cur);
449
450 /* add up live thread stats at the group level */
451 if (whole) {
452 struct task_struct *t = task;
453 do {
454 min_flt += t->min_flt;
455 maj_flt += t->maj_flt;
456 gtime += task_gtime(t);
457 } while_each_thread(task, t);
458
459 min_flt += sig->min_flt;
460 maj_flt += sig->maj_flt;
461 thread_group_cputime_adjusted(task, &utime, &stime);
462 gtime += sig->gtime;
463 }
464
465 sid = task_session_nr_ns(task, ns);
466 ppid = task_tgid_nr_ns(task->real_parent, ns);
467 pgid = task_pgrp_nr_ns(task, ns);
468
469 unlock_task_sighand(task, &flags);
470 }
471
472 if (permitted && (!whole || num_threads < 2))
473 wchan = get_wchan(task);
474 if (!whole) {
475 min_flt = task->min_flt;
476 maj_flt = task->maj_flt;
477 task_cputime_adjusted(task, &utime, &stime);
478 gtime = task_gtime(task);
479 }
480
481 /* scale priority and nice values from timeslices to -20..20 */
482 /* to make it look like a "normal" Unix priority/nice value */
483 priority = task_prio(task);
484 nice = task_nice(task);
485
486 /* convert nsec -> ticks */
487 start_time = nsec_to_clock_t(task->real_start_time);
488
489 seq_printf(m, "%d (%s) %c", pid_nr_ns(pid, ns), tcomm, state);
490 seq_put_decimal_ll(m, " ", ppid);
491 seq_put_decimal_ll(m, " ", pgid);
492 seq_put_decimal_ll(m, " ", sid);
493 seq_put_decimal_ll(m, " ", tty_nr);
494 seq_put_decimal_ll(m, " ", tty_pgrp);
495 seq_put_decimal_ull(m, " ", task->flags);
496 seq_put_decimal_ull(m, " ", min_flt);
497 seq_put_decimal_ull(m, " ", cmin_flt);
498 seq_put_decimal_ull(m, " ", maj_flt);
499 seq_put_decimal_ull(m, " ", cmaj_flt);
500 seq_put_decimal_ull(m, " ", cputime_to_clock_t(utime));
501 seq_put_decimal_ull(m, " ", cputime_to_clock_t(stime));
502 seq_put_decimal_ll(m, " ", cputime_to_clock_t(cutime));
503 seq_put_decimal_ll(m, " ", cputime_to_clock_t(cstime));
504 seq_put_decimal_ll(m, " ", priority);
505 seq_put_decimal_ll(m, " ", nice);
506 seq_put_decimal_ll(m, " ", num_threads);
507 seq_put_decimal_ull(m, " ", 0);
508 seq_put_decimal_ull(m, " ", start_time);
509 seq_put_decimal_ull(m, " ", vsize);
510 seq_put_decimal_ull(m, " ", mm ? get_mm_rss(mm) : 0);
511 seq_put_decimal_ull(m, " ", rsslim);
512 seq_put_decimal_ull(m, " ", mm ? (permitted ? mm->start_code : 1) : 0);
513 seq_put_decimal_ull(m, " ", mm ? (permitted ? mm->end_code : 1) : 0);
514 seq_put_decimal_ull(m, " ", (permitted && mm) ? mm->start_stack : 0);
515 seq_put_decimal_ull(m, " ", esp);
516 seq_put_decimal_ull(m, " ", eip);
517 /* The signal information here is obsolete.
518 * It must be decimal for Linux 2.0 compatibility.
519 * Use /proc/#/status for real-time signals.
520 */
521 seq_put_decimal_ull(m, " ", task->pending.signal.sig[0] & 0x7fffffffUL);
522 seq_put_decimal_ull(m, " ", task->blocked.sig[0] & 0x7fffffffUL);
523 seq_put_decimal_ull(m, " ", sigign.sig[0] & 0x7fffffffUL);
524 seq_put_decimal_ull(m, " ", sigcatch.sig[0] & 0x7fffffffUL);
525
526 /*
527 * We used to output the absolute kernel address, but that's an
528 * information leak - so instead we show a 0/1 flag here, to signal
529 * to user-space whether there's a wchan field in /proc/PID/wchan.
530 *
531 * This works with older implementations of procps as well.
532 */
533 if (wchan)
534 seq_puts(m, " 1");
535 else
536 seq_puts(m, " 0");
537
538 seq_put_decimal_ull(m, " ", 0);
539 seq_put_decimal_ull(m, " ", 0);
540 seq_put_decimal_ll(m, " ", task->exit_signal);
541 seq_put_decimal_ll(m, " ", task_cpu(task));
542 seq_put_decimal_ull(m, " ", task->rt_priority);
543 seq_put_decimal_ull(m, " ", task->policy);
544 seq_put_decimal_ull(m, " ", delayacct_blkio_ticks(task));
545 seq_put_decimal_ull(m, " ", cputime_to_clock_t(gtime));
546 seq_put_decimal_ll(m, " ", cputime_to_clock_t(cgtime));
547
548 if (mm && permitted) {
549 seq_put_decimal_ull(m, " ", mm->start_data);
550 seq_put_decimal_ull(m, " ", mm->end_data);
551 seq_put_decimal_ull(m, " ", mm->start_brk);
552 seq_put_decimal_ull(m, " ", mm->arg_start);
553 seq_put_decimal_ull(m, " ", mm->arg_end);
554 seq_put_decimal_ull(m, " ", mm->env_start);
555 seq_put_decimal_ull(m, " ", mm->env_end);
556 } else
557 seq_puts(m, " 0 0 0 0 0 0 0");
558
559 if (permitted)
560 seq_put_decimal_ll(m, " ", task->exit_code);
561 else
562 seq_puts(m, " 0");
563
564 seq_putc(m, '\n');
565 if (mm)
566 mmput(mm);
567 return 0;
568}
569
570int proc_tid_stat(struct seq_file *m, struct pid_namespace *ns,
571 struct pid *pid, struct task_struct *task)
572{
573 return do_task_stat(m, ns, pid, task, 0);
574}
575
576int proc_tgid_stat(struct seq_file *m, struct pid_namespace *ns,
577 struct pid *pid, struct task_struct *task)
578{
579 return do_task_stat(m, ns, pid, task, 1);
580}
581
582int proc_pid_statm(struct seq_file *m, struct pid_namespace *ns,
583 struct pid *pid, struct task_struct *task)
584{
585 unsigned long size = 0, resident = 0, shared = 0, text = 0, data = 0;
586 struct mm_struct *mm = get_task_mm(task);
587
588 if (mm) {
589 size = task_statm(mm, &shared, &text, &data, &resident);
590 mmput(mm);
591 }
592 /*
593 * For quick read, open code by putting numbers directly
594 * expected format is
595 * seq_printf(m, "%lu %lu %lu %lu 0 %lu 0\n",
596 * size, resident, shared, text, data);
597 */
598 seq_put_decimal_ull(m, "", size);
599 seq_put_decimal_ull(m, " ", resident);
600 seq_put_decimal_ull(m, " ", shared);
601 seq_put_decimal_ull(m, " ", text);
602 seq_put_decimal_ull(m, " ", 0);
603 seq_put_decimal_ull(m, " ", data);
604 seq_put_decimal_ull(m, " ", 0);
605 seq_putc(m, '\n');
606
607 return 0;
608}
609
610#ifdef CONFIG_PROC_CHILDREN
611static struct pid *
612get_children_pid(struct inode *inode, struct pid *pid_prev, loff_t pos)
613{
614 struct task_struct *start, *task;
615 struct pid *pid = NULL;
616
617 read_lock(&tasklist_lock);
618
619 start = pid_task(proc_pid(inode), PIDTYPE_PID);
620 if (!start)
621 goto out;
622
623 /*
624 * Lets try to continue searching first, this gives
625 * us significant speedup on children-rich processes.
626 */
627 if (pid_prev) {
628 task = pid_task(pid_prev, PIDTYPE_PID);
629 if (task && task->real_parent == start &&
630 !(list_empty(&task->sibling))) {
631 if (list_is_last(&task->sibling, &start->children))
632 goto out;
633 task = list_first_entry(&task->sibling,
634 struct task_struct, sibling);
635 pid = get_pid(task_pid(task));
636 goto out;
637 }
638 }
639
640 /*
641 * Slow search case.
642 *
643 * We might miss some children here if children
644 * are exited while we were not holding the lock,
645 * but it was never promised to be accurate that
646 * much.
647 *
648 * "Just suppose that the parent sleeps, but N children
649 * exit after we printed their tids. Now the slow paths
650 * skips N extra children, we miss N tasks." (c)
651 *
652 * So one need to stop or freeze the leader and all
653 * its children to get a precise result.
654 */
655 list_for_each_entry(task, &start->children, sibling) {
656 if (pos-- == 0) {
657 pid = get_pid(task_pid(task));
658 break;
659 }
660 }
661
662out:
663 read_unlock(&tasklist_lock);
664 return pid;
665}
666
667static int children_seq_show(struct seq_file *seq, void *v)
668{
669 struct inode *inode = seq->private;
670 pid_t pid;
671
672 pid = pid_nr_ns(v, inode->i_sb->s_fs_info);
673 seq_printf(seq, "%d ", pid);
674
675 return 0;
676}
677
678static void *children_seq_start(struct seq_file *seq, loff_t *pos)
679{
680 return get_children_pid(seq->private, NULL, *pos);
681}
682
683static void *children_seq_next(struct seq_file *seq, void *v, loff_t *pos)
684{
685 struct pid *pid;
686
687 pid = get_children_pid(seq->private, v, *pos + 1);
688 put_pid(v);
689
690 ++*pos;
691 return pid;
692}
693
694static void children_seq_stop(struct seq_file *seq, void *v)
695{
696 put_pid(v);
697}
698
699static const struct seq_operations children_seq_ops = {
700 .start = children_seq_start,
701 .next = children_seq_next,
702 .stop = children_seq_stop,
703 .show = children_seq_show,
704};
705
706static int children_seq_open(struct inode *inode, struct file *file)
707{
708 struct seq_file *m;
709 int ret;
710
711 ret = seq_open(file, &children_seq_ops);
712 if (ret)
713 return ret;
714
715 m = file->private_data;
716 m->private = inode;
717
718 return ret;
719}
720
721int children_seq_release(struct inode *inode, struct file *file)
722{
723 seq_release(inode, file);
724 return 0;
725}
726
727const struct file_operations proc_tid_children_operations = {
728 .open = children_seq_open,
729 .read = seq_read,
730 .llseek = seq_lseek,
731 .release = children_seq_release,
732};
733#endif /* CONFIG_PROC_CHILDREN */
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/user_namespace.h>
85
86#include <asm/pgtable.h>
87#include <asm/processor.h>
88#include "internal.h"
89
90static inline void task_name(struct seq_file *m, struct task_struct *p)
91{
92 int i;
93 char *buf, *end;
94 char *name;
95 char tcomm[sizeof(p->comm)];
96
97 get_task_comm(tcomm, p);
98
99 seq_puts(m, "Name:\t");
100 end = m->buf + m->size;
101 buf = m->buf + m->count;
102 name = tcomm;
103 i = sizeof(tcomm);
104 while (i && (buf < end)) {
105 unsigned char c = *name;
106 name++;
107 i--;
108 *buf = c;
109 if (!c)
110 break;
111 if (c == '\\') {
112 buf++;
113 if (buf < end)
114 *buf++ = c;
115 continue;
116 }
117 if (c == '\n') {
118 *buf++ = '\\';
119 if (buf < end)
120 *buf++ = 'n';
121 continue;
122 }
123 buf++;
124 }
125 m->count = buf - m->buf;
126 seq_putc(m, '\n');
127}
128
129/*
130 * The task state array is a strange "bitmap" of
131 * reasons to sleep. Thus "running" is zero, and
132 * you can test for combinations of others with
133 * simple bit tests.
134 */
135static const char * const task_state_array[] = {
136 "R (running)", /* 0 */
137 "S (sleeping)", /* 1 */
138 "D (disk sleep)", /* 2 */
139 "T (stopped)", /* 4 */
140 "t (tracing stop)", /* 8 */
141 "X (dead)", /* 16 */
142 "Z (zombie)", /* 32 */
143};
144
145static inline const char *get_task_state(struct task_struct *tsk)
146{
147 unsigned int state = (tsk->state | tsk->exit_state) & TASK_REPORT;
148
149 BUILD_BUG_ON(1 + ilog2(TASK_REPORT) != ARRAY_SIZE(task_state_array)-1);
150
151 return task_state_array[fls(state)];
152}
153
154static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
155 struct pid *pid, struct task_struct *p)
156{
157 struct user_namespace *user_ns = seq_user_ns(m);
158 struct group_info *group_info;
159 int g;
160 struct fdtable *fdt = NULL;
161 const struct cred *cred;
162 pid_t ppid, tpid;
163
164 rcu_read_lock();
165 ppid = pid_alive(p) ?
166 task_tgid_nr_ns(rcu_dereference(p->real_parent), ns) : 0;
167 tpid = 0;
168 if (pid_alive(p)) {
169 struct task_struct *tracer = ptrace_parent(p);
170 if (tracer)
171 tpid = task_pid_nr_ns(tracer, ns);
172 }
173 cred = get_task_cred(p);
174 seq_printf(m,
175 "State:\t%s\n"
176 "Tgid:\t%d\n"
177 "Ngid:\t%d\n"
178 "Pid:\t%d\n"
179 "PPid:\t%d\n"
180 "TracerPid:\t%d\n"
181 "Uid:\t%d\t%d\t%d\t%d\n"
182 "Gid:\t%d\t%d\t%d\t%d\n",
183 get_task_state(p),
184 task_tgid_nr_ns(p, ns),
185 task_numa_group_id(p),
186 pid_nr_ns(pid, ns),
187 ppid, tpid,
188 from_kuid_munged(user_ns, cred->uid),
189 from_kuid_munged(user_ns, cred->euid),
190 from_kuid_munged(user_ns, cred->suid),
191 from_kuid_munged(user_ns, cred->fsuid),
192 from_kgid_munged(user_ns, cred->gid),
193 from_kgid_munged(user_ns, cred->egid),
194 from_kgid_munged(user_ns, cred->sgid),
195 from_kgid_munged(user_ns, cred->fsgid));
196
197 task_lock(p);
198 if (p->files)
199 fdt = files_fdtable(p->files);
200 seq_printf(m,
201 "FDSize:\t%d\n"
202 "Groups:\t",
203 fdt ? fdt->max_fds : 0);
204 rcu_read_unlock();
205
206 group_info = cred->group_info;
207 task_unlock(p);
208
209 for (g = 0; g < group_info->ngroups; g++)
210 seq_printf(m, "%d ",
211 from_kgid_munged(user_ns, GROUP_AT(group_info, g)));
212 put_cred(cred);
213
214 seq_putc(m, '\n');
215}
216
217void render_sigset_t(struct seq_file *m, const char *header,
218 sigset_t *set)
219{
220 int i;
221
222 seq_puts(m, header);
223
224 i = _NSIG;
225 do {
226 int x = 0;
227
228 i -= 4;
229 if (sigismember(set, i+1)) x |= 1;
230 if (sigismember(set, i+2)) x |= 2;
231 if (sigismember(set, i+3)) x |= 4;
232 if (sigismember(set, i+4)) x |= 8;
233 seq_printf(m, "%x", x);
234 } while (i >= 4);
235
236 seq_putc(m, '\n');
237}
238
239static void collect_sigign_sigcatch(struct task_struct *p, sigset_t *ign,
240 sigset_t *catch)
241{
242 struct k_sigaction *k;
243 int i;
244
245 k = p->sighand->action;
246 for (i = 1; i <= _NSIG; ++i, ++k) {
247 if (k->sa.sa_handler == SIG_IGN)
248 sigaddset(ign, i);
249 else if (k->sa.sa_handler != SIG_DFL)
250 sigaddset(catch, i);
251 }
252}
253
254static inline void task_sig(struct seq_file *m, struct task_struct *p)
255{
256 unsigned long flags;
257 sigset_t pending, shpending, blocked, ignored, caught;
258 int num_threads = 0;
259 unsigned long qsize = 0;
260 unsigned long qlim = 0;
261
262 sigemptyset(&pending);
263 sigemptyset(&shpending);
264 sigemptyset(&blocked);
265 sigemptyset(&ignored);
266 sigemptyset(&caught);
267
268 if (lock_task_sighand(p, &flags)) {
269 pending = p->pending.signal;
270 shpending = p->signal->shared_pending.signal;
271 blocked = p->blocked;
272 collect_sigign_sigcatch(p, &ignored, &caught);
273 num_threads = get_nr_threads(p);
274 rcu_read_lock(); /* FIXME: is this correct? */
275 qsize = atomic_read(&__task_cred(p)->user->sigpending);
276 rcu_read_unlock();
277 qlim = task_rlimit(p, RLIMIT_SIGPENDING);
278 unlock_task_sighand(p, &flags);
279 }
280
281 seq_printf(m, "Threads:\t%d\n", num_threads);
282 seq_printf(m, "SigQ:\t%lu/%lu\n", qsize, qlim);
283
284 /* render them all */
285 render_sigset_t(m, "SigPnd:\t", &pending);
286 render_sigset_t(m, "ShdPnd:\t", &shpending);
287 render_sigset_t(m, "SigBlk:\t", &blocked);
288 render_sigset_t(m, "SigIgn:\t", &ignored);
289 render_sigset_t(m, "SigCgt:\t", &caught);
290}
291
292static void render_cap_t(struct seq_file *m, const char *header,
293 kernel_cap_t *a)
294{
295 unsigned __capi;
296
297 seq_puts(m, header);
298 CAP_FOR_EACH_U32(__capi) {
299 seq_printf(m, "%08x",
300 a->cap[(_KERNEL_CAPABILITY_U32S-1) - __capi]);
301 }
302 seq_putc(m, '\n');
303}
304
305/* Remove non-existent capabilities */
306#define NORM_CAPS(v) (v.cap[CAP_TO_INDEX(CAP_LAST_CAP)] &= \
307 CAP_TO_MASK(CAP_LAST_CAP + 1) - 1)
308
309static inline void task_cap(struct seq_file *m, struct task_struct *p)
310{
311 const struct cred *cred;
312 kernel_cap_t cap_inheritable, cap_permitted, cap_effective, cap_bset;
313
314 rcu_read_lock();
315 cred = __task_cred(p);
316 cap_inheritable = cred->cap_inheritable;
317 cap_permitted = cred->cap_permitted;
318 cap_effective = cred->cap_effective;
319 cap_bset = cred->cap_bset;
320 rcu_read_unlock();
321
322 NORM_CAPS(cap_inheritable);
323 NORM_CAPS(cap_permitted);
324 NORM_CAPS(cap_effective);
325 NORM_CAPS(cap_bset);
326
327 render_cap_t(m, "CapInh:\t", &cap_inheritable);
328 render_cap_t(m, "CapPrm:\t", &cap_permitted);
329 render_cap_t(m, "CapEff:\t", &cap_effective);
330 render_cap_t(m, "CapBnd:\t", &cap_bset);
331}
332
333static inline void task_seccomp(struct seq_file *m, struct task_struct *p)
334{
335#ifdef CONFIG_SECCOMP
336 seq_printf(m, "Seccomp:\t%d\n", p->seccomp.mode);
337#endif
338}
339
340static inline void task_context_switch_counts(struct seq_file *m,
341 struct task_struct *p)
342{
343 seq_printf(m, "voluntary_ctxt_switches:\t%lu\n"
344 "nonvoluntary_ctxt_switches:\t%lu\n",
345 p->nvcsw,
346 p->nivcsw);
347}
348
349static void task_cpus_allowed(struct seq_file *m, struct task_struct *task)
350{
351 seq_puts(m, "Cpus_allowed:\t");
352 seq_cpumask(m, &task->cpus_allowed);
353 seq_putc(m, '\n');
354 seq_puts(m, "Cpus_allowed_list:\t");
355 seq_cpumask_list(m, &task->cpus_allowed);
356 seq_putc(m, '\n');
357}
358
359int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
360 struct pid *pid, struct task_struct *task)
361{
362 struct mm_struct *mm = get_task_mm(task);
363
364 task_name(m, task);
365 task_state(m, ns, pid, task);
366
367 if (mm) {
368 task_mem(m, mm);
369 mmput(mm);
370 }
371 task_sig(m, task);
372 task_cap(m, task);
373 task_seccomp(m, task);
374 task_cpus_allowed(m, task);
375 cpuset_task_status_allowed(m, task);
376 task_context_switch_counts(m, task);
377 return 0;
378}
379
380static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
381 struct pid *pid, struct task_struct *task, int whole)
382{
383 unsigned long vsize, eip, esp, wchan = ~0UL;
384 int priority, nice;
385 int tty_pgrp = -1, tty_nr = 0;
386 sigset_t sigign, sigcatch;
387 char state;
388 pid_t ppid = 0, pgid = -1, sid = -1;
389 int num_threads = 0;
390 int permitted;
391 struct mm_struct *mm;
392 unsigned long long start_time;
393 unsigned long cmin_flt = 0, cmaj_flt = 0;
394 unsigned long min_flt = 0, maj_flt = 0;
395 cputime_t cutime, cstime, utime, stime;
396 cputime_t cgtime, gtime;
397 unsigned long rsslim = 0;
398 char tcomm[sizeof(task->comm)];
399 unsigned long flags;
400
401 state = *get_task_state(task);
402 vsize = eip = esp = 0;
403 permitted = ptrace_may_access(task, PTRACE_MODE_READ | PTRACE_MODE_NOAUDIT);
404 mm = get_task_mm(task);
405 if (mm) {
406 vsize = task_vsize(mm);
407 if (permitted) {
408 eip = KSTK_EIP(task);
409 esp = KSTK_ESP(task);
410 }
411 }
412
413 get_task_comm(tcomm, task);
414
415 sigemptyset(&sigign);
416 sigemptyset(&sigcatch);
417 cutime = cstime = utime = stime = 0;
418 cgtime = gtime = 0;
419
420 if (lock_task_sighand(task, &flags)) {
421 struct signal_struct *sig = task->signal;
422
423 if (sig->tty) {
424 struct pid *pgrp = tty_get_pgrp(sig->tty);
425 tty_pgrp = pid_nr_ns(pgrp, ns);
426 put_pid(pgrp);
427 tty_nr = new_encode_dev(tty_devnum(sig->tty));
428 }
429
430 num_threads = get_nr_threads(task);
431 collect_sigign_sigcatch(task, &sigign, &sigcatch);
432
433 cmin_flt = sig->cmin_flt;
434 cmaj_flt = sig->cmaj_flt;
435 cutime = sig->cutime;
436 cstime = sig->cstime;
437 cgtime = sig->cgtime;
438 rsslim = ACCESS_ONCE(sig->rlim[RLIMIT_RSS].rlim_cur);
439
440 /* add up live thread stats at the group level */
441 if (whole) {
442 struct task_struct *t = task;
443 do {
444 min_flt += t->min_flt;
445 maj_flt += t->maj_flt;
446 gtime += task_gtime(t);
447 } while_each_thread(task, t);
448
449 min_flt += sig->min_flt;
450 maj_flt += sig->maj_flt;
451 thread_group_cputime_adjusted(task, &utime, &stime);
452 gtime += sig->gtime;
453 }
454
455 sid = task_session_nr_ns(task, ns);
456 ppid = task_tgid_nr_ns(task->real_parent, ns);
457 pgid = task_pgrp_nr_ns(task, ns);
458
459 unlock_task_sighand(task, &flags);
460 }
461
462 if (permitted && (!whole || num_threads < 2))
463 wchan = get_wchan(task);
464 if (!whole) {
465 min_flt = task->min_flt;
466 maj_flt = task->maj_flt;
467 task_cputime_adjusted(task, &utime, &stime);
468 gtime = task_gtime(task);
469 }
470
471 /* scale priority and nice values from timeslices to -20..20 */
472 /* to make it look like a "normal" Unix priority/nice value */
473 priority = task_prio(task);
474 nice = task_nice(task);
475
476 /* Temporary variable needed for gcc-2.96 */
477 /* convert timespec -> nsec*/
478 start_time =
479 (unsigned long long)task->real_start_time.tv_sec * NSEC_PER_SEC
480 + task->real_start_time.tv_nsec;
481 /* convert nsec -> ticks */
482 start_time = nsec_to_clock_t(start_time);
483
484 seq_printf(m, "%d (%s) %c", pid_nr_ns(pid, ns), tcomm, state);
485 seq_put_decimal_ll(m, ' ', ppid);
486 seq_put_decimal_ll(m, ' ', pgid);
487 seq_put_decimal_ll(m, ' ', sid);
488 seq_put_decimal_ll(m, ' ', tty_nr);
489 seq_put_decimal_ll(m, ' ', tty_pgrp);
490 seq_put_decimal_ull(m, ' ', task->flags);
491 seq_put_decimal_ull(m, ' ', min_flt);
492 seq_put_decimal_ull(m, ' ', cmin_flt);
493 seq_put_decimal_ull(m, ' ', maj_flt);
494 seq_put_decimal_ull(m, ' ', cmaj_flt);
495 seq_put_decimal_ull(m, ' ', cputime_to_clock_t(utime));
496 seq_put_decimal_ull(m, ' ', cputime_to_clock_t(stime));
497 seq_put_decimal_ll(m, ' ', cputime_to_clock_t(cutime));
498 seq_put_decimal_ll(m, ' ', cputime_to_clock_t(cstime));
499 seq_put_decimal_ll(m, ' ', priority);
500 seq_put_decimal_ll(m, ' ', nice);
501 seq_put_decimal_ll(m, ' ', num_threads);
502 seq_put_decimal_ull(m, ' ', 0);
503 seq_put_decimal_ull(m, ' ', start_time);
504 seq_put_decimal_ull(m, ' ', vsize);
505 seq_put_decimal_ull(m, ' ', mm ? get_mm_rss(mm) : 0);
506 seq_put_decimal_ull(m, ' ', rsslim);
507 seq_put_decimal_ull(m, ' ', mm ? (permitted ? mm->start_code : 1) : 0);
508 seq_put_decimal_ull(m, ' ', mm ? (permitted ? mm->end_code : 1) : 0);
509 seq_put_decimal_ull(m, ' ', (permitted && mm) ? mm->start_stack : 0);
510 seq_put_decimal_ull(m, ' ', esp);
511 seq_put_decimal_ull(m, ' ', eip);
512 /* The signal information here is obsolete.
513 * It must be decimal for Linux 2.0 compatibility.
514 * Use /proc/#/status for real-time signals.
515 */
516 seq_put_decimal_ull(m, ' ', task->pending.signal.sig[0] & 0x7fffffffUL);
517 seq_put_decimal_ull(m, ' ', task->blocked.sig[0] & 0x7fffffffUL);
518 seq_put_decimal_ull(m, ' ', sigign.sig[0] & 0x7fffffffUL);
519 seq_put_decimal_ull(m, ' ', sigcatch.sig[0] & 0x7fffffffUL);
520 seq_put_decimal_ull(m, ' ', wchan);
521 seq_put_decimal_ull(m, ' ', 0);
522 seq_put_decimal_ull(m, ' ', 0);
523 seq_put_decimal_ll(m, ' ', task->exit_signal);
524 seq_put_decimal_ll(m, ' ', task_cpu(task));
525 seq_put_decimal_ull(m, ' ', task->rt_priority);
526 seq_put_decimal_ull(m, ' ', task->policy);
527 seq_put_decimal_ull(m, ' ', delayacct_blkio_ticks(task));
528 seq_put_decimal_ull(m, ' ', cputime_to_clock_t(gtime));
529 seq_put_decimal_ll(m, ' ', cputime_to_clock_t(cgtime));
530
531 if (mm && permitted) {
532 seq_put_decimal_ull(m, ' ', mm->start_data);
533 seq_put_decimal_ull(m, ' ', mm->end_data);
534 seq_put_decimal_ull(m, ' ', mm->start_brk);
535 seq_put_decimal_ull(m, ' ', mm->arg_start);
536 seq_put_decimal_ull(m, ' ', mm->arg_end);
537 seq_put_decimal_ull(m, ' ', mm->env_start);
538 seq_put_decimal_ull(m, ' ', mm->env_end);
539 } else
540 seq_printf(m, " 0 0 0 0 0 0 0");
541
542 if (permitted)
543 seq_put_decimal_ll(m, ' ', task->exit_code);
544 else
545 seq_put_decimal_ll(m, ' ', 0);
546
547 seq_putc(m, '\n');
548 if (mm)
549 mmput(mm);
550 return 0;
551}
552
553int proc_tid_stat(struct seq_file *m, struct pid_namespace *ns,
554 struct pid *pid, struct task_struct *task)
555{
556 return do_task_stat(m, ns, pid, task, 0);
557}
558
559int proc_tgid_stat(struct seq_file *m, struct pid_namespace *ns,
560 struct pid *pid, struct task_struct *task)
561{
562 return do_task_stat(m, ns, pid, task, 1);
563}
564
565int proc_pid_statm(struct seq_file *m, struct pid_namespace *ns,
566 struct pid *pid, struct task_struct *task)
567{
568 unsigned long size = 0, resident = 0, shared = 0, text = 0, data = 0;
569 struct mm_struct *mm = get_task_mm(task);
570
571 if (mm) {
572 size = task_statm(mm, &shared, &text, &data, &resident);
573 mmput(mm);
574 }
575 /*
576 * For quick read, open code by putting numbers directly
577 * expected format is
578 * seq_printf(m, "%lu %lu %lu %lu 0 %lu 0\n",
579 * size, resident, shared, text, data);
580 */
581 seq_put_decimal_ull(m, 0, size);
582 seq_put_decimal_ull(m, ' ', resident);
583 seq_put_decimal_ull(m, ' ', shared);
584 seq_put_decimal_ull(m, ' ', text);
585 seq_put_decimal_ull(m, ' ', 0);
586 seq_put_decimal_ull(m, ' ', data);
587 seq_put_decimal_ull(m, ' ', 0);
588 seq_putc(m, '\n');
589
590 return 0;
591}
592
593#ifdef CONFIG_CHECKPOINT_RESTORE
594static struct pid *
595get_children_pid(struct inode *inode, struct pid *pid_prev, loff_t pos)
596{
597 struct task_struct *start, *task;
598 struct pid *pid = NULL;
599
600 read_lock(&tasklist_lock);
601
602 start = pid_task(proc_pid(inode), PIDTYPE_PID);
603 if (!start)
604 goto out;
605
606 /*
607 * Lets try to continue searching first, this gives
608 * us significant speedup on children-rich processes.
609 */
610 if (pid_prev) {
611 task = pid_task(pid_prev, PIDTYPE_PID);
612 if (task && task->real_parent == start &&
613 !(list_empty(&task->sibling))) {
614 if (list_is_last(&task->sibling, &start->children))
615 goto out;
616 task = list_first_entry(&task->sibling,
617 struct task_struct, sibling);
618 pid = get_pid(task_pid(task));
619 goto out;
620 }
621 }
622
623 /*
624 * Slow search case.
625 *
626 * We might miss some children here if children
627 * are exited while we were not holding the lock,
628 * but it was never promised to be accurate that
629 * much.
630 *
631 * "Just suppose that the parent sleeps, but N children
632 * exit after we printed their tids. Now the slow paths
633 * skips N extra children, we miss N tasks." (c)
634 *
635 * So one need to stop or freeze the leader and all
636 * its children to get a precise result.
637 */
638 list_for_each_entry(task, &start->children, sibling) {
639 if (pos-- == 0) {
640 pid = get_pid(task_pid(task));
641 break;
642 }
643 }
644
645out:
646 read_unlock(&tasklist_lock);
647 return pid;
648}
649
650static int children_seq_show(struct seq_file *seq, void *v)
651{
652 struct inode *inode = seq->private;
653 pid_t pid;
654
655 pid = pid_nr_ns(v, inode->i_sb->s_fs_info);
656 return seq_printf(seq, "%d ", pid);
657}
658
659static void *children_seq_start(struct seq_file *seq, loff_t *pos)
660{
661 return get_children_pid(seq->private, NULL, *pos);
662}
663
664static void *children_seq_next(struct seq_file *seq, void *v, loff_t *pos)
665{
666 struct pid *pid;
667
668 pid = get_children_pid(seq->private, v, *pos + 1);
669 put_pid(v);
670
671 ++*pos;
672 return pid;
673}
674
675static void children_seq_stop(struct seq_file *seq, void *v)
676{
677 put_pid(v);
678}
679
680static const struct seq_operations children_seq_ops = {
681 .start = children_seq_start,
682 .next = children_seq_next,
683 .stop = children_seq_stop,
684 .show = children_seq_show,
685};
686
687static int children_seq_open(struct inode *inode, struct file *file)
688{
689 struct seq_file *m;
690 int ret;
691
692 ret = seq_open(file, &children_seq_ops);
693 if (ret)
694 return ret;
695
696 m = file->private_data;
697 m->private = inode;
698
699 return ret;
700}
701
702int children_seq_release(struct inode *inode, struct file *file)
703{
704 seq_release(inode, file);
705 return 0;
706}
707
708const struct file_operations proc_tid_children_operations = {
709 .open = children_seq_open,
710 .read = seq_read,
711 .llseek = seq_lseek,
712 .release = children_seq_release,
713};
714#endif /* CONFIG_CHECKPOINT_RESTORE */