xref: /openbmc/linux/fs/proc/array.c (revision 7dd65feb) 
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/slab.h>
72 #include <linux/smp.h>
73 #include <linux/signal.h>
74 #include <linux/highmem.h>
75 #include <linux/file.h>
76 #include <linux/fdtable.h>
77 #include <linux/times.h>
78 #include <linux/cpuset.h>
79 #include <linux/rcupdate.h>
80 #include <linux/delayacct.h>
81 #include <linux/seq_file.h>
82 #include <linux/pid_namespace.h>
83 #include <linux/ptrace.h>
84 #include <linux/tracehook.h>
85 #include <linux/swapops.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 	int i;
94 	char *buf, *end;
95 	char *name;
96 	char tcomm[sizeof(p->comm)];
97 
98 	get_task_comm(tcomm, p);
99 
100 	seq_printf(m, "Name:\t");
101 	end = m->buf + m->size;
102 	buf = m->buf + m->count;
103 	name = tcomm;
104 	i = sizeof(tcomm);
105 	while (i && (buf < end)) {
106 		unsigned char c = *name;
107 		name++;
108 		i--;
109 		*buf = c;
110 		if (!c)
111 			break;
112 		if (c == '\\') {
113 			buf++;
114 			if (buf < end)
115 				*buf++ = c;
116 			continue;
117 		}
118 		if (c == '\n') {
119 			*buf++ = '\\';
120 			if (buf < end)
121 				*buf++ = 'n';
122 			continue;
123 		}
124 		buf++;
125 	}
126 	m->count = buf - m->buf;
127 	seq_printf(m, "\n");
128 }
129 
130 /*
131  * The task state array is a strange "bitmap" of
132  * reasons to sleep. Thus "running" is zero, and
133  * you can test for combinations of others with
134  * simple bit tests.
135  */
136 static const char *task_state_array[] = {
137 	"R (running)",		/*   0 */
138 	"S (sleeping)",		/*   1 */
139 	"D (disk sleep)",	/*   2 */
140 	"T (stopped)",		/*   4 */
141 	"t (tracing stop)",	/*   8 */
142 	"Z (zombie)",		/*  16 */
143 	"X (dead)",		/*  32 */
144 	"x (dead)",		/*  64 */
145 	"K (wakekill)",		/* 128 */
146 	"W (waking)",		/* 256 */
147 };
148 
149 static inline const char *get_task_state(struct task_struct *tsk)
150 {
151 	unsigned int state = (tsk->state & TASK_REPORT) | tsk->exit_state;
152 	const char **p = &task_state_array[0];
153 
154 	BUILD_BUG_ON(1 + ilog2(TASK_STATE_MAX) != ARRAY_SIZE(task_state_array));
155 
156 	while (state) {
157 		p++;
158 		state >>= 1;
159 	}
160 	return *p;
161 }
162 
163 static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
164 				struct pid *pid, struct task_struct *p)
165 {
166 	struct group_info *group_info;
167 	int g;
168 	struct fdtable *fdt = NULL;
169 	const struct cred *cred;
170 	pid_t ppid, tpid;
171 
172 	rcu_read_lock();
173 	ppid = pid_alive(p) ?
174 		task_tgid_nr_ns(rcu_dereference(p->real_parent), ns) : 0;
175 	tpid = 0;
176 	if (pid_alive(p)) {
177 		struct task_struct *tracer = tracehook_tracer_task(p);
178 		if (tracer)
179 			tpid = task_pid_nr_ns(tracer, ns);
180 	}
181 	cred = get_cred((struct cred *) __task_cred(p));
182 	seq_printf(m,
183 		"State:\t%s\n"
184 		"Tgid:\t%d\n"
185 		"Pid:\t%d\n"
186 		"PPid:\t%d\n"
187 		"TracerPid:\t%d\n"
188 		"Uid:\t%d\t%d\t%d\t%d\n"
189 		"Gid:\t%d\t%d\t%d\t%d\n",
190 		get_task_state(p),
191 		task_tgid_nr_ns(p, ns),
192 		pid_nr_ns(pid, ns),
193 		ppid, tpid,
194 		cred->uid, cred->euid, cred->suid, cred->fsuid,
195 		cred->gid, cred->egid, cred->sgid, 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 < min(group_info->ngroups, NGROUPS_SMALL); g++)
210 		seq_printf(m, "%d ", GROUP_AT(group_info, g));
211 	put_cred(cred);
212 
213 	seq_printf(m, "\n");
214 }
215 
216 static void render_sigset_t(struct seq_file *m, const char *header,
217 				sigset_t *set)
218 {
219 	int i;
220 
221 	seq_printf(m, "%s", header);
222 
223 	i = _NSIG;
224 	do {
225 		int x = 0;
226 
227 		i -= 4;
228 		if (sigismember(set, i+1)) x |= 1;
229 		if (sigismember(set, i+2)) x |= 2;
230 		if (sigismember(set, i+3)) x |= 4;
231 		if (sigismember(set, i+4)) x |= 8;
232 		seq_printf(m, "%x", x);
233 	} while (i >= 4);
234 
235 	seq_printf(m, "\n");
236 }
237 
238 static void collect_sigign_sigcatch(struct task_struct *p, sigset_t *ign,
239 				    sigset_t *catch)
240 {
241 	struct k_sigaction *k;
242 	int i;
243 
244 	k = p->sighand->action;
245 	for (i = 1; i <= _NSIG; ++i, ++k) {
246 		if (k->sa.sa_handler == SIG_IGN)
247 			sigaddset(ign, i);
248 		else if (k->sa.sa_handler != SIG_DFL)
249 			sigaddset(catch, i);
250 	}
251 }
252 
253 static inline void task_sig(struct seq_file *m, struct task_struct *p)
254 {
255 	unsigned long flags;
256 	sigset_t pending, shpending, blocked, ignored, caught;
257 	int num_threads = 0;
258 	unsigned long qsize = 0;
259 	unsigned long qlim = 0;
260 
261 	sigemptyset(&pending);
262 	sigemptyset(&shpending);
263 	sigemptyset(&blocked);
264 	sigemptyset(&ignored);
265 	sigemptyset(&caught);
266 
267 	if (lock_task_sighand(p, &flags)) {
268 		pending = p->pending.signal;
269 		shpending = p->signal->shared_pending.signal;
270 		blocked = p->blocked;
271 		collect_sigign_sigcatch(p, &ignored, &caught);
272 		num_threads = atomic_read(&p->signal->count);
273 		qsize = atomic_read(&__task_cred(p)->user->sigpending);
274 		qlim = p->signal->rlim[RLIMIT_SIGPENDING].rlim_cur;
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_printf(m, "%s", header);
295 	CAP_FOR_EACH_U32(__capi) {
296 		seq_printf(m, "%08x",
297 			   a->cap[(_KERNEL_CAPABILITY_U32S-1) - __capi]);
298 	}
299 	seq_printf(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 #ifdef CONFIG_MMU
331 
332 struct stack_stats {
333 	struct vm_area_struct *vma;
334 	unsigned long	startpage;
335 	unsigned long	usage;
336 };
337 
338 static int stack_usage_pte_range(pmd_t *pmd, unsigned long addr,
339 				unsigned long end, struct mm_walk *walk)
340 {
341 	struct stack_stats *ss = walk->private;
342 	struct vm_area_struct *vma = ss->vma;
343 	pte_t *pte, ptent;
344 	spinlock_t *ptl;
345 	int ret = 0;
346 
347 	pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
348 	for (; addr != end; pte++, addr += PAGE_SIZE) {
349 		ptent = *pte;
350 
351 #ifdef CONFIG_STACK_GROWSUP
352 		if (pte_present(ptent) || is_swap_pte(ptent))
353 			ss->usage = addr - ss->startpage + PAGE_SIZE;
354 #else
355 		if (pte_present(ptent) || is_swap_pte(ptent)) {
356 			ss->usage = ss->startpage - addr + PAGE_SIZE;
357 			pte++;
358 			ret = 1;
359 			break;
360 		}
361 #endif
362 	}
363 	pte_unmap_unlock(pte - 1, ptl);
364 	cond_resched();
365 	return ret;
366 }
367 
368 static inline unsigned long get_stack_usage_in_bytes(struct vm_area_struct *vma,
369 				struct task_struct *task)
370 {
371 	struct stack_stats ss;
372 	struct mm_walk stack_walk = {
373 		.pmd_entry = stack_usage_pte_range,
374 		.mm = vma->vm_mm,
375 		.private = &ss,
376 	};
377 
378 	if (!vma->vm_mm || is_vm_hugetlb_page(vma))
379 		return 0;
380 
381 	ss.vma = vma;
382 	ss.startpage = task->stack_start & PAGE_MASK;
383 	ss.usage = 0;
384 
385 #ifdef CONFIG_STACK_GROWSUP
386 	walk_page_range(KSTK_ESP(task) & PAGE_MASK, vma->vm_end,
387 		&stack_walk);
388 #else
389 	walk_page_range(vma->vm_start, (KSTK_ESP(task) & PAGE_MASK) + PAGE_SIZE,
390 		&stack_walk);
391 #endif
392 	return ss.usage;
393 }
394 
395 static inline void task_show_stack_usage(struct seq_file *m,
396 						struct task_struct *task)
397 {
398 	struct vm_area_struct	*vma;
399 	struct mm_struct	*mm = get_task_mm(task);
400 
401 	if (mm) {
402 		down_read(&mm->mmap_sem);
403 		vma = find_vma(mm, task->stack_start);
404 		if (vma)
405 			seq_printf(m, "Stack usage:\t%lu kB\n",
406 				get_stack_usage_in_bytes(vma, task) >> 10);
407 
408 		up_read(&mm->mmap_sem);
409 		mmput(mm);
410 	}
411 }
412 #else
413 static void task_show_stack_usage(struct seq_file *m, struct task_struct *task)
414 {
415 }
416 #endif		/* CONFIG_MMU */
417 
418 static void task_cpus_allowed(struct seq_file *m, struct task_struct *task)
419 {
420 	seq_printf(m, "Cpus_allowed:\t");
421 	seq_cpumask(m, &task->cpus_allowed);
422 	seq_printf(m, "\n");
423 	seq_printf(m, "Cpus_allowed_list:\t");
424 	seq_cpumask_list(m, &task->cpus_allowed);
425 	seq_printf(m, "\n");
426 }
427 
428 int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
429 			struct pid *pid, struct task_struct *task)
430 {
431 	struct mm_struct *mm = get_task_mm(task);
432 
433 	task_name(m, task);
434 	task_state(m, ns, pid, task);
435 
436 	if (mm) {
437 		task_mem(m, mm);
438 		mmput(mm);
439 	}
440 	task_sig(m, task);
441 	task_cap(m, task);
442 	task_cpus_allowed(m, task);
443 	cpuset_task_status_allowed(m, task);
444 #if defined(CONFIG_S390)
445 	task_show_regs(m, task);
446 #endif
447 	task_context_switch_counts(m, task);
448 	task_show_stack_usage(m, task);
449 	return 0;
450 }
451 
452 static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
453 			struct pid *pid, struct task_struct *task, int whole)
454 {
455 	unsigned long vsize, eip, esp, wchan = ~0UL;
456 	long priority, nice;
457 	int tty_pgrp = -1, tty_nr = 0;
458 	sigset_t sigign, sigcatch;
459 	char state;
460 	pid_t ppid = 0, pgid = -1, sid = -1;
461 	int num_threads = 0;
462 	int permitted;
463 	struct mm_struct *mm;
464 	unsigned long long start_time;
465 	unsigned long cmin_flt = 0, cmaj_flt = 0;
466 	unsigned long  min_flt = 0,  maj_flt = 0;
467 	cputime_t cutime, cstime, utime, stime;
468 	cputime_t cgtime, gtime;
469 	unsigned long rsslim = 0;
470 	char tcomm[sizeof(task->comm)];
471 	unsigned long flags;
472 
473 	state = *get_task_state(task);
474 	vsize = eip = esp = 0;
475 	permitted = ptrace_may_access(task, PTRACE_MODE_READ);
476 	mm = get_task_mm(task);
477 	if (mm) {
478 		vsize = task_vsize(mm);
479 		if (permitted) {
480 			eip = KSTK_EIP(task);
481 			esp = KSTK_ESP(task);
482 		}
483 	}
484 
485 	get_task_comm(tcomm, task);
486 
487 	sigemptyset(&sigign);
488 	sigemptyset(&sigcatch);
489 	cutime = cstime = utime = stime = cputime_zero;
490 	cgtime = gtime = cputime_zero;
491 
492 	if (lock_task_sighand(task, &flags)) {
493 		struct signal_struct *sig = task->signal;
494 
495 		if (sig->tty) {
496 			struct pid *pgrp = tty_get_pgrp(sig->tty);
497 			tty_pgrp = pid_nr_ns(pgrp, ns);
498 			put_pid(pgrp);
499 			tty_nr = new_encode_dev(tty_devnum(sig->tty));
500 		}
501 
502 		num_threads = atomic_read(&sig->count);
503 		collect_sigign_sigcatch(task, &sigign, &sigcatch);
504 
505 		cmin_flt = sig->cmin_flt;
506 		cmaj_flt = sig->cmaj_flt;
507 		cutime = sig->cutime;
508 		cstime = sig->cstime;
509 		cgtime = sig->cgtime;
510 		rsslim = sig->rlim[RLIMIT_RSS].rlim_cur;
511 
512 		/* add up live thread stats at the group level */
513 		if (whole) {
514 			struct task_struct *t = task;
515 			do {
516 				min_flt += t->min_flt;
517 				maj_flt += t->maj_flt;
518 				gtime = cputime_add(gtime, t->gtime);
519 				t = next_thread(t);
520 			} while (t != task);
521 
522 			min_flt += sig->min_flt;
523 			maj_flt += sig->maj_flt;
524 			thread_group_times(task, &utime, &stime);
525 			gtime = cputime_add(gtime, sig->gtime);
526 		}
527 
528 		sid = task_session_nr_ns(task, ns);
529 		ppid = task_tgid_nr_ns(task->real_parent, ns);
530 		pgid = task_pgrp_nr_ns(task, ns);
531 
532 		unlock_task_sighand(task, &flags);
533 	}
534 
535 	if (permitted && (!whole || num_threads < 2))
536 		wchan = get_wchan(task);
537 	if (!whole) {
538 		min_flt = task->min_flt;
539 		maj_flt = task->maj_flt;
540 		task_times(task, &utime, &stime);
541 		gtime = task->gtime;
542 	}
543 
544 	/* scale priority and nice values from timeslices to -20..20 */
545 	/* to make it look like a "normal" Unix priority/nice value  */
546 	priority = task_prio(task);
547 	nice = task_nice(task);
548 
549 	/* Temporary variable needed for gcc-2.96 */
550 	/* convert timespec -> nsec*/
551 	start_time =
552 		(unsigned long long)task->real_start_time.tv_sec * NSEC_PER_SEC
553 				+ task->real_start_time.tv_nsec;
554 	/* convert nsec -> ticks */
555 	start_time = nsec_to_clock_t(start_time);
556 
557 	seq_printf(m, "%d (%s) %c %d %d %d %d %d %u %lu \
558 %lu %lu %lu %lu %lu %ld %ld %ld %ld %d 0 %llu %lu %ld %lu %lu %lu %lu %lu \
559 %lu %lu %lu %lu %lu %lu %lu %lu %d %d %u %u %llu %lu %ld\n",
560 		pid_nr_ns(pid, ns),
561 		tcomm,
562 		state,
563 		ppid,
564 		pgid,
565 		sid,
566 		tty_nr,
567 		tty_pgrp,
568 		task->flags,
569 		min_flt,
570 		cmin_flt,
571 		maj_flt,
572 		cmaj_flt,
573 		cputime_to_clock_t(utime),
574 		cputime_to_clock_t(stime),
575 		cputime_to_clock_t(cutime),
576 		cputime_to_clock_t(cstime),
577 		priority,
578 		nice,
579 		num_threads,
580 		start_time,
581 		vsize,
582 		mm ? get_mm_rss(mm) : 0,
583 		rsslim,
584 		mm ? mm->start_code : 0,
585 		mm ? mm->end_code : 0,
586 		(permitted && mm) ? task->stack_start : 0,
587 		esp,
588 		eip,
589 		/* The signal information here is obsolete.
590 		 * It must be decimal for Linux 2.0 compatibility.
591 		 * Use /proc/#/status for real-time signals.
592 		 */
593 		task->pending.signal.sig[0] & 0x7fffffffUL,
594 		task->blocked.sig[0] & 0x7fffffffUL,
595 		sigign      .sig[0] & 0x7fffffffUL,
596 		sigcatch    .sig[0] & 0x7fffffffUL,
597 		wchan,
598 		0UL,
599 		0UL,
600 		task->exit_signal,
601 		task_cpu(task),
602 		task->rt_priority,
603 		task->policy,
604 		(unsigned long long)delayacct_blkio_ticks(task),
605 		cputime_to_clock_t(gtime),
606 		cputime_to_clock_t(cgtime));
607 	if (mm)
608 		mmput(mm);
609 	return 0;
610 }
611 
612 int proc_tid_stat(struct seq_file *m, struct pid_namespace *ns,
613 			struct pid *pid, struct task_struct *task)
614 {
615 	return do_task_stat(m, ns, pid, task, 0);
616 }
617 
618 int proc_tgid_stat(struct seq_file *m, struct pid_namespace *ns,
619 			struct pid *pid, struct task_struct *task)
620 {
621 	return do_task_stat(m, ns, pid, task, 1);
622 }
623 
624 int proc_pid_statm(struct seq_file *m, struct pid_namespace *ns,
625 			struct pid *pid, struct task_struct *task)
626 {
627 	int size = 0, resident = 0, shared = 0, text = 0, lib = 0, data = 0;
628 	struct mm_struct *mm = get_task_mm(task);
629 
630 	if (mm) {
631 		size = task_statm(mm, &shared, &text, &data, &resident);
632 		mmput(mm);
633 	}
634 	seq_printf(m, "%d %d %d %d %d %d %d\n",
635 			size, resident, shared, text, lib, data, 0);
636 
637 	return 0;
638 }
639