xref: /openbmc/linux/fs/proc/array.c (revision 3252b11f) 
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 };
145 
146 static inline const char *get_task_state(struct task_struct *tsk)
147 {
148 	unsigned int state = (tsk->state & TASK_REPORT) | tsk->exit_state;
149 	const char **p = &task_state_array[0];
150 
151 	while (state) {
152 		p++;
153 		state >>= 1;
154 	}
155 	return *p;
156 }
157 
158 static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
159 				struct pid *pid, struct task_struct *p)
160 {
161 	struct group_info *group_info;
162 	int g;
163 	struct fdtable *fdt = NULL;
164 	const struct cred *cred;
165 	pid_t ppid, tpid;
166 
167 	rcu_read_lock();
168 	ppid = pid_alive(p) ?
169 		task_tgid_nr_ns(rcu_dereference(p->real_parent), ns) : 0;
170 	tpid = 0;
171 	if (pid_alive(p)) {
172 		struct task_struct *tracer = tracehook_tracer_task(p);
173 		if (tracer)
174 			tpid = task_pid_nr_ns(tracer, ns);
175 	}
176 	cred = get_cred((struct cred *) __task_cred(p));
177 	seq_printf(m,
178 		"State:\t%s\n"
179 		"Tgid:\t%d\n"
180 		"Pid:\t%d\n"
181 		"PPid:\t%d\n"
182 		"TracerPid:\t%d\n"
183 		"Uid:\t%d\t%d\t%d\t%d\n"
184 		"Gid:\t%d\t%d\t%d\t%d\n",
185 		get_task_state(p),
186 		task_tgid_nr_ns(p, ns),
187 		pid_nr_ns(pid, ns),
188 		ppid, tpid,
189 		cred->uid, cred->euid, cred->suid, cred->fsuid,
190 		cred->gid, cred->egid, cred->sgid, cred->fsgid);
191 
192 	task_lock(p);
193 	if (p->files)
194 		fdt = files_fdtable(p->files);
195 	seq_printf(m,
196 		"FDSize:\t%d\n"
197 		"Groups:\t",
198 		fdt ? fdt->max_fds : 0);
199 	rcu_read_unlock();
200 
201 	group_info = cred->group_info;
202 	task_unlock(p);
203 
204 	for (g = 0; g < min(group_info->ngroups, NGROUPS_SMALL); g++)
205 		seq_printf(m, "%d ", GROUP_AT(group_info, g));
206 	put_cred(cred);
207 
208 	seq_printf(m, "\n");
209 }
210 
211 static void render_sigset_t(struct seq_file *m, const char *header,
212 				sigset_t *set)
213 {
214 	int i;
215 
216 	seq_printf(m, "%s", header);
217 
218 	i = _NSIG;
219 	do {
220 		int x = 0;
221 
222 		i -= 4;
223 		if (sigismember(set, i+1)) x |= 1;
224 		if (sigismember(set, i+2)) x |= 2;
225 		if (sigismember(set, i+3)) x |= 4;
226 		if (sigismember(set, i+4)) x |= 8;
227 		seq_printf(m, "%x", x);
228 	} while (i >= 4);
229 
230 	seq_printf(m, "\n");
231 }
232 
233 static void collect_sigign_sigcatch(struct task_struct *p, sigset_t *ign,
234 				    sigset_t *catch)
235 {
236 	struct k_sigaction *k;
237 	int i;
238 
239 	k = p->sighand->action;
240 	for (i = 1; i <= _NSIG; ++i, ++k) {
241 		if (k->sa.sa_handler == SIG_IGN)
242 			sigaddset(ign, i);
243 		else if (k->sa.sa_handler != SIG_DFL)
244 			sigaddset(catch, i);
245 	}
246 }
247 
248 static inline void task_sig(struct seq_file *m, struct task_struct *p)
249 {
250 	unsigned long flags;
251 	sigset_t pending, shpending, blocked, ignored, caught;
252 	int num_threads = 0;
253 	unsigned long qsize = 0;
254 	unsigned long qlim = 0;
255 
256 	sigemptyset(&pending);
257 	sigemptyset(&shpending);
258 	sigemptyset(&blocked);
259 	sigemptyset(&ignored);
260 	sigemptyset(&caught);
261 
262 	if (lock_task_sighand(p, &flags)) {
263 		pending = p->pending.signal;
264 		shpending = p->signal->shared_pending.signal;
265 		blocked = p->blocked;
266 		collect_sigign_sigcatch(p, &ignored, &caught);
267 		num_threads = atomic_read(&p->signal->count);
268 		qsize = atomic_read(&__task_cred(p)->user->sigpending);
269 		qlim = p->signal->rlim[RLIMIT_SIGPENDING].rlim_cur;
270 		unlock_task_sighand(p, &flags);
271 	}
272 
273 	seq_printf(m, "Threads:\t%d\n", num_threads);
274 	seq_printf(m, "SigQ:\t%lu/%lu\n", qsize, qlim);
275 
276 	/* render them all */
277 	render_sigset_t(m, "SigPnd:\t", &pending);
278 	render_sigset_t(m, "ShdPnd:\t", &shpending);
279 	render_sigset_t(m, "SigBlk:\t", &blocked);
280 	render_sigset_t(m, "SigIgn:\t", &ignored);
281 	render_sigset_t(m, "SigCgt:\t", &caught);
282 }
283 
284 static void render_cap_t(struct seq_file *m, const char *header,
285 			kernel_cap_t *a)
286 {
287 	unsigned __capi;
288 
289 	seq_printf(m, "%s", header);
290 	CAP_FOR_EACH_U32(__capi) {
291 		seq_printf(m, "%08x",
292 			   a->cap[(_KERNEL_CAPABILITY_U32S-1) - __capi]);
293 	}
294 	seq_printf(m, "\n");
295 }
296 
297 static inline void task_cap(struct seq_file *m, struct task_struct *p)
298 {
299 	const struct cred *cred;
300 	kernel_cap_t cap_inheritable, cap_permitted, cap_effective, cap_bset;
301 
302 	rcu_read_lock();
303 	cred = __task_cred(p);
304 	cap_inheritable	= cred->cap_inheritable;
305 	cap_permitted	= cred->cap_permitted;
306 	cap_effective	= cred->cap_effective;
307 	cap_bset	= cred->cap_bset;
308 	rcu_read_unlock();
309 
310 	render_cap_t(m, "CapInh:\t", &cap_inheritable);
311 	render_cap_t(m, "CapPrm:\t", &cap_permitted);
312 	render_cap_t(m, "CapEff:\t", &cap_effective);
313 	render_cap_t(m, "CapBnd:\t", &cap_bset);
314 }
315 
316 static inline void task_context_switch_counts(struct seq_file *m,
317 						struct task_struct *p)
318 {
319 	seq_printf(m,	"voluntary_ctxt_switches:\t%lu\n"
320 			"nonvoluntary_ctxt_switches:\t%lu\n",
321 			p->nvcsw,
322 			p->nivcsw);
323 }
324 
325 #ifdef CONFIG_MMU
326 
327 struct stack_stats {
328 	struct vm_area_struct *vma;
329 	unsigned long	startpage;
330 	unsigned long	usage;
331 };
332 
333 static int stack_usage_pte_range(pmd_t *pmd, unsigned long addr,
334 				unsigned long end, struct mm_walk *walk)
335 {
336 	struct stack_stats *ss = walk->private;
337 	struct vm_area_struct *vma = ss->vma;
338 	pte_t *pte, ptent;
339 	spinlock_t *ptl;
340 	int ret = 0;
341 
342 	pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
343 	for (; addr != end; pte++, addr += PAGE_SIZE) {
344 		ptent = *pte;
345 
346 #ifdef CONFIG_STACK_GROWSUP
347 		if (pte_present(ptent) || is_swap_pte(ptent))
348 			ss->usage = addr - ss->startpage + PAGE_SIZE;
349 #else
350 		if (pte_present(ptent) || is_swap_pte(ptent)) {
351 			ss->usage = ss->startpage - addr + PAGE_SIZE;
352 			pte++;
353 			ret = 1;
354 			break;
355 		}
356 #endif
357 	}
358 	pte_unmap_unlock(pte - 1, ptl);
359 	cond_resched();
360 	return ret;
361 }
362 
363 static inline unsigned long get_stack_usage_in_bytes(struct vm_area_struct *vma,
364 				struct task_struct *task)
365 {
366 	struct stack_stats ss;
367 	struct mm_walk stack_walk = {
368 		.pmd_entry = stack_usage_pte_range,
369 		.mm = vma->vm_mm,
370 		.private = &ss,
371 	};
372 
373 	if (!vma->vm_mm || is_vm_hugetlb_page(vma))
374 		return 0;
375 
376 	ss.vma = vma;
377 	ss.startpage = task->stack_start & PAGE_MASK;
378 	ss.usage = 0;
379 
380 #ifdef CONFIG_STACK_GROWSUP
381 	walk_page_range(KSTK_ESP(task) & PAGE_MASK, vma->vm_end,
382 		&stack_walk);
383 #else
384 	walk_page_range(vma->vm_start, (KSTK_ESP(task) & PAGE_MASK) + PAGE_SIZE,
385 		&stack_walk);
386 #endif
387 	return ss.usage;
388 }
389 
390 static inline void task_show_stack_usage(struct seq_file *m,
391 						struct task_struct *task)
392 {
393 	struct vm_area_struct	*vma;
394 	struct mm_struct	*mm = get_task_mm(task);
395 
396 	if (mm) {
397 		down_read(&mm->mmap_sem);
398 		vma = find_vma(mm, task->stack_start);
399 		if (vma)
400 			seq_printf(m, "Stack usage:\t%lu kB\n",
401 				get_stack_usage_in_bytes(vma, task) >> 10);
402 
403 		up_read(&mm->mmap_sem);
404 		mmput(mm);
405 	}
406 }
407 #else
408 static void task_show_stack_usage(struct seq_file *m, struct task_struct *task)
409 {
410 }
411 #endif		/* CONFIG_MMU */
412 
413 static void task_cpus_allowed(struct seq_file *m, struct task_struct *task)
414 {
415 	seq_printf(m, "Cpus_allowed:\t");
416 	seq_cpumask(m, &task->cpus_allowed);
417 	seq_printf(m, "\n");
418 	seq_printf(m, "Cpus_allowed_list:\t");
419 	seq_cpumask_list(m, &task->cpus_allowed);
420 	seq_printf(m, "\n");
421 }
422 
423 int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
424 			struct pid *pid, struct task_struct *task)
425 {
426 	struct mm_struct *mm = get_task_mm(task);
427 
428 	task_name(m, task);
429 	task_state(m, ns, pid, task);
430 
431 	if (mm) {
432 		task_mem(m, mm);
433 		mmput(mm);
434 	}
435 	task_sig(m, task);
436 	task_cap(m, task);
437 	task_cpus_allowed(m, task);
438 	cpuset_task_status_allowed(m, task);
439 #if defined(CONFIG_S390)
440 	task_show_regs(m, task);
441 #endif
442 	task_context_switch_counts(m, task);
443 	task_show_stack_usage(m, task);
444 	return 0;
445 }
446 
447 static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
448 			struct pid *pid, struct task_struct *task, int whole)
449 {
450 	unsigned long vsize, eip, esp, wchan = ~0UL;
451 	long priority, nice;
452 	int tty_pgrp = -1, tty_nr = 0;
453 	sigset_t sigign, sigcatch;
454 	char state;
455 	pid_t ppid = 0, pgid = -1, sid = -1;
456 	int num_threads = 0;
457 	int permitted;
458 	struct mm_struct *mm;
459 	unsigned long long start_time;
460 	unsigned long cmin_flt = 0, cmaj_flt = 0;
461 	unsigned long  min_flt = 0,  maj_flt = 0;
462 	cputime_t cutime, cstime, utime, stime;
463 	cputime_t cgtime, gtime;
464 	unsigned long rsslim = 0;
465 	char tcomm[sizeof(task->comm)];
466 	unsigned long flags;
467 
468 	state = *get_task_state(task);
469 	vsize = eip = esp = 0;
470 	permitted = ptrace_may_access(task, PTRACE_MODE_READ);
471 	mm = get_task_mm(task);
472 	if (mm) {
473 		vsize = task_vsize(mm);
474 		if (permitted) {
475 			eip = KSTK_EIP(task);
476 			esp = KSTK_ESP(task);
477 		}
478 	}
479 
480 	get_task_comm(tcomm, task);
481 
482 	sigemptyset(&sigign);
483 	sigemptyset(&sigcatch);
484 	cutime = cstime = utime = stime = cputime_zero;
485 	cgtime = gtime = cputime_zero;
486 
487 	if (lock_task_sighand(task, &flags)) {
488 		struct signal_struct *sig = task->signal;
489 
490 		if (sig->tty) {
491 			struct pid *pgrp = tty_get_pgrp(sig->tty);
492 			tty_pgrp = pid_nr_ns(pgrp, ns);
493 			put_pid(pgrp);
494 			tty_nr = new_encode_dev(tty_devnum(sig->tty));
495 		}
496 
497 		num_threads = atomic_read(&sig->count);
498 		collect_sigign_sigcatch(task, &sigign, &sigcatch);
499 
500 		cmin_flt = sig->cmin_flt;
501 		cmaj_flt = sig->cmaj_flt;
502 		cutime = sig->cutime;
503 		cstime = sig->cstime;
504 		cgtime = sig->cgtime;
505 		rsslim = sig->rlim[RLIMIT_RSS].rlim_cur;
506 
507 		/* add up live thread stats at the group level */
508 		if (whole) {
509 			struct task_struct *t = task;
510 			do {
511 				min_flt += t->min_flt;
512 				maj_flt += t->maj_flt;
513 				gtime = cputime_add(gtime, t->gtime);
514 				t = next_thread(t);
515 			} while (t != task);
516 
517 			min_flt += sig->min_flt;
518 			maj_flt += sig->maj_flt;
519 			thread_group_times(task, &utime, &stime);
520 			gtime = cputime_add(gtime, sig->gtime);
521 		}
522 
523 		sid = task_session_nr_ns(task, ns);
524 		ppid = task_tgid_nr_ns(task->real_parent, ns);
525 		pgid = task_pgrp_nr_ns(task, ns);
526 
527 		unlock_task_sighand(task, &flags);
528 	}
529 
530 	if (permitted && (!whole || num_threads < 2))
531 		wchan = get_wchan(task);
532 	if (!whole) {
533 		min_flt = task->min_flt;
534 		maj_flt = task->maj_flt;
535 		task_times(task, &utime, &stime);
536 		gtime = task->gtime;
537 	}
538 
539 	/* scale priority and nice values from timeslices to -20..20 */
540 	/* to make it look like a "normal" Unix priority/nice value  */
541 	priority = task_prio(task);
542 	nice = task_nice(task);
543 
544 	/* Temporary variable needed for gcc-2.96 */
545 	/* convert timespec -> nsec*/
546 	start_time =
547 		(unsigned long long)task->real_start_time.tv_sec * NSEC_PER_SEC
548 				+ task->real_start_time.tv_nsec;
549 	/* convert nsec -> ticks */
550 	start_time = nsec_to_clock_t(start_time);
551 
552 	seq_printf(m, "%d (%s) %c %d %d %d %d %d %u %lu \
553 %lu %lu %lu %lu %lu %ld %ld %ld %ld %d 0 %llu %lu %ld %lu %lu %lu %lu %lu \
554 %lu %lu %lu %lu %lu %lu %lu %lu %d %d %u %u %llu %lu %ld\n",
555 		pid_nr_ns(pid, ns),
556 		tcomm,
557 		state,
558 		ppid,
559 		pgid,
560 		sid,
561 		tty_nr,
562 		tty_pgrp,
563 		task->flags,
564 		min_flt,
565 		cmin_flt,
566 		maj_flt,
567 		cmaj_flt,
568 		cputime_to_clock_t(utime),
569 		cputime_to_clock_t(stime),
570 		cputime_to_clock_t(cutime),
571 		cputime_to_clock_t(cstime),
572 		priority,
573 		nice,
574 		num_threads,
575 		start_time,
576 		vsize,
577 		mm ? get_mm_rss(mm) : 0,
578 		rsslim,
579 		mm ? mm->start_code : 0,
580 		mm ? mm->end_code : 0,
581 		(permitted && mm) ? task->stack_start : 0,
582 		esp,
583 		eip,
584 		/* The signal information here is obsolete.
585 		 * It must be decimal for Linux 2.0 compatibility.
586 		 * Use /proc/#/status for real-time signals.
587 		 */
588 		task->pending.signal.sig[0] & 0x7fffffffUL,
589 		task->blocked.sig[0] & 0x7fffffffUL,
590 		sigign      .sig[0] & 0x7fffffffUL,
591 		sigcatch    .sig[0] & 0x7fffffffUL,
592 		wchan,
593 		0UL,
594 		0UL,
595 		task->exit_signal,
596 		task_cpu(task),
597 		task->rt_priority,
598 		task->policy,
599 		(unsigned long long)delayacct_blkio_ticks(task),
600 		cputime_to_clock_t(gtime),
601 		cputime_to_clock_t(cgtime));
602 	if (mm)
603 		mmput(mm);
604 	return 0;
605 }
606 
607 int proc_tid_stat(struct seq_file *m, struct pid_namespace *ns,
608 			struct pid *pid, struct task_struct *task)
609 {
610 	return do_task_stat(m, ns, pid, task, 0);
611 }
612 
613 int proc_tgid_stat(struct seq_file *m, struct pid_namespace *ns,
614 			struct pid *pid, struct task_struct *task)
615 {
616 	return do_task_stat(m, ns, pid, task, 1);
617 }
618 
619 int proc_pid_statm(struct seq_file *m, struct pid_namespace *ns,
620 			struct pid *pid, struct task_struct *task)
621 {
622 	int size = 0, resident = 0, shared = 0, text = 0, lib = 0, data = 0;
623 	struct mm_struct *mm = get_task_mm(task);
624 
625 	if (mm) {
626 		size = task_statm(mm, &shared, &text, &data, &resident);
627 		mmput(mm);
628 	}
629 	seq_printf(m, "%d %d %d %d %d %d %d\n",
630 			size, resident, shared, text, lib, data, 0);
631 
632 	return 0;
633 }
634