xref: /openbmc/linux/fs/proc/array.c (revision 4800cd83) 
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 
85 #include <asm/pgtable.h>
86 #include <asm/processor.h>
87 #include "internal.h"
88 
89 static inline void task_name(struct seq_file *m, struct task_struct *p)
90 {
91 	int i;
92 	char *buf, *end;
93 	char *name;
94 	char tcomm[sizeof(p->comm)];
95 
96 	get_task_comm(tcomm, p);
97 
98 	seq_puts(m, "Name:\t");
99 	end = m->buf + m->size;
100 	buf = m->buf + m->count;
101 	name = tcomm;
102 	i = sizeof(tcomm);
103 	while (i && (buf < end)) {
104 		unsigned char c = *name;
105 		name++;
106 		i--;
107 		*buf = c;
108 		if (!c)
109 			break;
110 		if (c == '\\') {
111 			buf++;
112 			if (buf < end)
113 				*buf++ = c;
114 			continue;
115 		}
116 		if (c == '\n') {
117 			*buf++ = '\\';
118 			if (buf < end)
119 				*buf++ = 'n';
120 			continue;
121 		}
122 		buf++;
123 	}
124 	m->count = buf - m->buf;
125 	seq_putc(m, '\n');
126 }
127 
128 /*
129  * The task state array is a strange "bitmap" of
130  * reasons to sleep. Thus "running" is zero, and
131  * you can test for combinations of others with
132  * simple bit tests.
133  */
134 static const char *task_state_array[] = {
135 	"R (running)",		/*   0 */
136 	"S (sleeping)",		/*   1 */
137 	"D (disk sleep)",	/*   2 */
138 	"T (stopped)",		/*   4 */
139 	"t (tracing stop)",	/*   8 */
140 	"Z (zombie)",		/*  16 */
141 	"X (dead)",		/*  32 */
142 	"x (dead)",		/*  64 */
143 	"K (wakekill)",		/* 128 */
144 	"W (waking)",		/* 256 */
145 };
146 
147 static inline const char *get_task_state(struct task_struct *tsk)
148 {
149 	unsigned int state = (tsk->state & TASK_REPORT) | tsk->exit_state;
150 	const char **p = &task_state_array[0];
151 
152 	BUILD_BUG_ON(1 + ilog2(TASK_STATE_MAX) != ARRAY_SIZE(task_state_array));
153 
154 	while (state) {
155 		p++;
156 		state >>= 1;
157 	}
158 	return *p;
159 }
160 
161 static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
162 				struct pid *pid, struct task_struct *p)
163 {
164 	struct group_info *group_info;
165 	int g;
166 	struct fdtable *fdt = NULL;
167 	const struct cred *cred;
168 	pid_t ppid, tpid;
169 
170 	rcu_read_lock();
171 	ppid = pid_alive(p) ?
172 		task_tgid_nr_ns(rcu_dereference(p->real_parent), ns) : 0;
173 	tpid = 0;
174 	if (pid_alive(p)) {
175 		struct task_struct *tracer = tracehook_tracer_task(p);
176 		if (tracer)
177 			tpid = task_pid_nr_ns(tracer, ns);
178 	}
179 	cred = get_task_cred(p);
180 	seq_printf(m,
181 		"State:\t%s\n"
182 		"Tgid:\t%d\n"
183 		"Pid:\t%d\n"
184 		"PPid:\t%d\n"
185 		"TracerPid:\t%d\n"
186 		"Uid:\t%d\t%d\t%d\t%d\n"
187 		"Gid:\t%d\t%d\t%d\t%d\n",
188 		get_task_state(p),
189 		task_tgid_nr_ns(p, ns),
190 		pid_nr_ns(pid, ns),
191 		ppid, tpid,
192 		cred->uid, cred->euid, cred->suid, cred->fsuid,
193 		cred->gid, cred->egid, cred->sgid, cred->fsgid);
194 
195 	task_lock(p);
196 	if (p->files)
197 		fdt = files_fdtable(p->files);
198 	seq_printf(m,
199 		"FDSize:\t%d\n"
200 		"Groups:\t",
201 		fdt ? fdt->max_fds : 0);
202 	rcu_read_unlock();
203 
204 	group_info = cred->group_info;
205 	task_unlock(p);
206 
207 	for (g = 0; g < min(group_info->ngroups, NGROUPS_SMALL); g++)
208 		seq_printf(m, "%d ", GROUP_AT(group_info, g));
209 	put_cred(cred);
210 
211 	seq_putc(m, '\n');
212 }
213 
214 static void render_sigset_t(struct seq_file *m, const char *header,
215 				sigset_t *set)
216 {
217 	int i;
218 
219 	seq_puts(m, header);
220 
221 	i = _NSIG;
222 	do {
223 		int x = 0;
224 
225 		i -= 4;
226 		if (sigismember(set, i+1)) x |= 1;
227 		if (sigismember(set, i+2)) x |= 2;
228 		if (sigismember(set, i+3)) x |= 4;
229 		if (sigismember(set, i+4)) x |= 8;
230 		seq_printf(m, "%x", x);
231 	} while (i >= 4);
232 
233 	seq_putc(m, '\n');
234 }
235 
236 static void collect_sigign_sigcatch(struct task_struct *p, sigset_t *ign,
237 				    sigset_t *catch)
238 {
239 	struct k_sigaction *k;
240 	int i;
241 
242 	k = p->sighand->action;
243 	for (i = 1; i <= _NSIG; ++i, ++k) {
244 		if (k->sa.sa_handler == SIG_IGN)
245 			sigaddset(ign, i);
246 		else if (k->sa.sa_handler != SIG_DFL)
247 			sigaddset(catch, i);
248 	}
249 }
250 
251 static inline void task_sig(struct seq_file *m, struct task_struct *p)
252 {
253 	unsigned long flags;
254 	sigset_t pending, shpending, blocked, ignored, caught;
255 	int num_threads = 0;
256 	unsigned long qsize = 0;
257 	unsigned long qlim = 0;
258 
259 	sigemptyset(&pending);
260 	sigemptyset(&shpending);
261 	sigemptyset(&blocked);
262 	sigemptyset(&ignored);
263 	sigemptyset(&caught);
264 
265 	if (lock_task_sighand(p, &flags)) {
266 		pending = p->pending.signal;
267 		shpending = p->signal->shared_pending.signal;
268 		blocked = p->blocked;
269 		collect_sigign_sigcatch(p, &ignored, &caught);
270 		num_threads = get_nr_threads(p);
271 		rcu_read_lock();  /* FIXME: is this correct? */
272 		qsize = atomic_read(&__task_cred(p)->user->sigpending);
273 		rcu_read_unlock();
274 		qlim = task_rlimit(p, RLIMIT_SIGPENDING);
275 		unlock_task_sighand(p, &flags);
276 	}
277 
278 	seq_printf(m, "Threads:\t%d\n", num_threads);
279 	seq_printf(m, "SigQ:\t%lu/%lu\n", qsize, qlim);
280 
281 	/* render them all */
282 	render_sigset_t(m, "SigPnd:\t", &pending);
283 	render_sigset_t(m, "ShdPnd:\t", &shpending);
284 	render_sigset_t(m, "SigBlk:\t", &blocked);
285 	render_sigset_t(m, "SigIgn:\t", &ignored);
286 	render_sigset_t(m, "SigCgt:\t", &caught);
287 }
288 
289 static void render_cap_t(struct seq_file *m, const char *header,
290 			kernel_cap_t *a)
291 {
292 	unsigned __capi;
293 
294 	seq_puts(m, header);
295 	CAP_FOR_EACH_U32(__capi) {
296 		seq_printf(m, "%08x",
297 			   a->cap[(_KERNEL_CAPABILITY_U32S-1) - __capi]);
298 	}
299 	seq_putc(m, '\n');
300 }
301 
302 static inline void task_cap(struct seq_file *m, struct task_struct *p)
303 {
304 	const struct cred *cred;
305 	kernel_cap_t cap_inheritable, cap_permitted, cap_effective, cap_bset;
306 
307 	rcu_read_lock();
308 	cred = __task_cred(p);
309 	cap_inheritable	= cred->cap_inheritable;
310 	cap_permitted	= cred->cap_permitted;
311 	cap_effective	= cred->cap_effective;
312 	cap_bset	= cred->cap_bset;
313 	rcu_read_unlock();
314 
315 	render_cap_t(m, "CapInh:\t", &cap_inheritable);
316 	render_cap_t(m, "CapPrm:\t", &cap_permitted);
317 	render_cap_t(m, "CapEff:\t", &cap_effective);
318 	render_cap_t(m, "CapBnd:\t", &cap_bset);
319 }
320 
321 static inline void task_context_switch_counts(struct seq_file *m,
322 						struct task_struct *p)
323 {
324 	seq_printf(m,	"voluntary_ctxt_switches:\t%lu\n"
325 			"nonvoluntary_ctxt_switches:\t%lu\n",
326 			p->nvcsw,
327 			p->nivcsw);
328 }
329 
330 static void task_cpus_allowed(struct seq_file *m, struct task_struct *task)
331 {
332 	seq_puts(m, "Cpus_allowed:\t");
333 	seq_cpumask(m, &task->cpus_allowed);
334 	seq_putc(m, '\n');
335 	seq_puts(m, "Cpus_allowed_list:\t");
336 	seq_cpumask_list(m, &task->cpus_allowed);
337 	seq_putc(m, '\n');
338 }
339 
340 int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
341 			struct pid *pid, struct task_struct *task)
342 {
343 	struct mm_struct *mm = get_task_mm(task);
344 
345 	task_name(m, task);
346 	task_state(m, ns, pid, task);
347 
348 	if (mm) {
349 		task_mem(m, mm);
350 		mmput(mm);
351 	}
352 	task_sig(m, task);
353 	task_cap(m, task);
354 	task_cpus_allowed(m, task);
355 	cpuset_task_status_allowed(m, task);
356 	task_context_switch_counts(m, task);
357 	return 0;
358 }
359 
360 static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
361 			struct pid *pid, struct task_struct *task, int whole)
362 {
363 	unsigned long vsize, eip, esp, wchan = ~0UL;
364 	long priority, nice;
365 	int tty_pgrp = -1, tty_nr = 0;
366 	sigset_t sigign, sigcatch;
367 	char state;
368 	pid_t ppid = 0, pgid = -1, sid = -1;
369 	int num_threads = 0;
370 	int permitted;
371 	struct mm_struct *mm;
372 	unsigned long long start_time;
373 	unsigned long cmin_flt = 0, cmaj_flt = 0;
374 	unsigned long  min_flt = 0,  maj_flt = 0;
375 	cputime_t cutime, cstime, utime, stime;
376 	cputime_t cgtime, gtime;
377 	unsigned long rsslim = 0;
378 	char tcomm[sizeof(task->comm)];
379 	unsigned long flags;
380 
381 	state = *get_task_state(task);
382 	vsize = eip = esp = 0;
383 	permitted = ptrace_may_access(task, PTRACE_MODE_READ);
384 	mm = get_task_mm(task);
385 	if (mm) {
386 		vsize = task_vsize(mm);
387 		if (permitted) {
388 			eip = KSTK_EIP(task);
389 			esp = KSTK_ESP(task);
390 		}
391 	}
392 
393 	get_task_comm(tcomm, task);
394 
395 	sigemptyset(&sigign);
396 	sigemptyset(&sigcatch);
397 	cutime = cstime = utime = stime = cputime_zero;
398 	cgtime = gtime = cputime_zero;
399 
400 	if (lock_task_sighand(task, &flags)) {
401 		struct signal_struct *sig = task->signal;
402 
403 		if (sig->tty) {
404 			struct pid *pgrp = tty_get_pgrp(sig->tty);
405 			tty_pgrp = pid_nr_ns(pgrp, ns);
406 			put_pid(pgrp);
407 			tty_nr = new_encode_dev(tty_devnum(sig->tty));
408 		}
409 
410 		num_threads = get_nr_threads(task);
411 		collect_sigign_sigcatch(task, &sigign, &sigcatch);
412 
413 		cmin_flt = sig->cmin_flt;
414 		cmaj_flt = sig->cmaj_flt;
415 		cutime = sig->cutime;
416 		cstime = sig->cstime;
417 		cgtime = sig->cgtime;
418 		rsslim = ACCESS_ONCE(sig->rlim[RLIMIT_RSS].rlim_cur);
419 
420 		/* add up live thread stats at the group level */
421 		if (whole) {
422 			struct task_struct *t = task;
423 			do {
424 				min_flt += t->min_flt;
425 				maj_flt += t->maj_flt;
426 				gtime = cputime_add(gtime, t->gtime);
427 				t = next_thread(t);
428 			} while (t != task);
429 
430 			min_flt += sig->min_flt;
431 			maj_flt += sig->maj_flt;
432 			thread_group_times(task, &utime, &stime);
433 			gtime = cputime_add(gtime, sig->gtime);
434 		}
435 
436 		sid = task_session_nr_ns(task, ns);
437 		ppid = task_tgid_nr_ns(task->real_parent, ns);
438 		pgid = task_pgrp_nr_ns(task, ns);
439 
440 		unlock_task_sighand(task, &flags);
441 	}
442 
443 	if (permitted && (!whole || num_threads < 2))
444 		wchan = get_wchan(task);
445 	if (!whole) {
446 		min_flt = task->min_flt;
447 		maj_flt = task->maj_flt;
448 		task_times(task, &utime, &stime);
449 		gtime = task->gtime;
450 	}
451 
452 	/* scale priority and nice values from timeslices to -20..20 */
453 	/* to make it look like a "normal" Unix priority/nice value  */
454 	priority = task_prio(task);
455 	nice = task_nice(task);
456 
457 	/* Temporary variable needed for gcc-2.96 */
458 	/* convert timespec -> nsec*/
459 	start_time =
460 		(unsigned long long)task->real_start_time.tv_sec * NSEC_PER_SEC
461 				+ task->real_start_time.tv_nsec;
462 	/* convert nsec -> ticks */
463 	start_time = nsec_to_clock_t(start_time);
464 
465 	seq_printf(m, "%d (%s) %c %d %d %d %d %d %u %lu \
466 %lu %lu %lu %lu %lu %ld %ld %ld %ld %d 0 %llu %lu %ld %lu %lu %lu %lu %lu \
467 %lu %lu %lu %lu %lu %lu %lu %lu %d %d %u %u %llu %lu %ld\n",
468 		pid_nr_ns(pid, ns),
469 		tcomm,
470 		state,
471 		ppid,
472 		pgid,
473 		sid,
474 		tty_nr,
475 		tty_pgrp,
476 		task->flags,
477 		min_flt,
478 		cmin_flt,
479 		maj_flt,
480 		cmaj_flt,
481 		cputime_to_clock_t(utime),
482 		cputime_to_clock_t(stime),
483 		cputime_to_clock_t(cutime),
484 		cputime_to_clock_t(cstime),
485 		priority,
486 		nice,
487 		num_threads,
488 		start_time,
489 		vsize,
490 		mm ? get_mm_rss(mm) : 0,
491 		rsslim,
492 		mm ? mm->start_code : 0,
493 		mm ? mm->end_code : 0,
494 		(permitted && mm) ? mm->start_stack : 0,
495 		esp,
496 		eip,
497 		/* The signal information here is obsolete.
498 		 * It must be decimal for Linux 2.0 compatibility.
499 		 * Use /proc/#/status for real-time signals.
500 		 */
501 		task->pending.signal.sig[0] & 0x7fffffffUL,
502 		task->blocked.sig[0] & 0x7fffffffUL,
503 		sigign      .sig[0] & 0x7fffffffUL,
504 		sigcatch    .sig[0] & 0x7fffffffUL,
505 		wchan,
506 		0UL,
507 		0UL,
508 		task->exit_signal,
509 		task_cpu(task),
510 		task->rt_priority,
511 		task->policy,
512 		(unsigned long long)delayacct_blkio_ticks(task),
513 		cputime_to_clock_t(gtime),
514 		cputime_to_clock_t(cgtime));
515 	if (mm)
516 		mmput(mm);
517 	return 0;
518 }
519 
520 int proc_tid_stat(struct seq_file *m, struct pid_namespace *ns,
521 			struct pid *pid, struct task_struct *task)
522 {
523 	return do_task_stat(m, ns, pid, task, 0);
524 }
525 
526 int proc_tgid_stat(struct seq_file *m, struct pid_namespace *ns,
527 			struct pid *pid, struct task_struct *task)
528 {
529 	return do_task_stat(m, ns, pid, task, 1);
530 }
531 
532 int proc_pid_statm(struct seq_file *m, struct pid_namespace *ns,
533 			struct pid *pid, struct task_struct *task)
534 {
535 	unsigned long size = 0, resident = 0, shared = 0, text = 0, data = 0;
536 	struct mm_struct *mm = get_task_mm(task);
537 
538 	if (mm) {
539 		size = task_statm(mm, &shared, &text, &data, &resident);
540 		mmput(mm);
541 	}
542 	seq_printf(m, "%lu %lu %lu %lu 0 %lu 0\n",
543 			size, resident, shared, text, data);
544 
545 	return 0;
546 }
547