Btrfs: Fix uninitialized root flags for subvolumes
[firefly-linux-kernel-4.4.55.git] / fs / proc / array.c
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
86 #include <asm/pgtable.h>
87 #include <asm/processor.h>
88 #include "internal.h"
89
90 static 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_printf(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_printf(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  */
135 static const char *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         "Z (zombie)",           /* 16 */
142         "X (dead)"              /* 32 */
143 };
144
145 static inline const char *get_task_state(struct task_struct *tsk)
146 {
147         unsigned int state = (tsk->state & TASK_REPORT) | tsk->exit_state;
148         const char **p = &task_state_array[0];
149
150         while (state) {
151                 p++;
152                 state >>= 1;
153         }
154         return *p;
155 }
156
157 static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
158                                 struct pid *pid, struct task_struct *p)
159 {
160         struct group_info *group_info;
161         int g;
162         struct fdtable *fdt = NULL;
163         const struct cred *cred;
164         pid_t ppid, tpid;
165
166         rcu_read_lock();
167         ppid = pid_alive(p) ?
168                 task_tgid_nr_ns(rcu_dereference(p->real_parent), ns) : 0;
169         tpid = 0;
170         if (pid_alive(p)) {
171                 struct task_struct *tracer = tracehook_tracer_task(p);
172                 if (tracer)
173                         tpid = task_pid_nr_ns(tracer, ns);
174         }
175         cred = get_task_cred(p);
176         seq_printf(m,
177                 "State:\t%s\n"
178                 "Tgid:\t%d\n"
179                 "Pid:\t%d\n"
180                 "PPid:\t%d\n"
181                 "TracerPid:\t%d\n"
182                 "Uid:\t%d\t%d\t%d\t%d\n"
183                 "Gid:\t%d\t%d\t%d\t%d\n",
184                 get_task_state(p),
185                 task_tgid_nr_ns(p, ns),
186                 pid_nr_ns(pid, ns),
187                 ppid, tpid,
188                 cred->uid, cred->euid, cred->suid, cred->fsuid,
189                 cred->gid, cred->egid, cred->sgid, cred->fsgid);
190
191         task_lock(p);
192         if (p->files)
193                 fdt = files_fdtable(p->files);
194         seq_printf(m,
195                 "FDSize:\t%d\n"
196                 "Groups:\t",
197                 fdt ? fdt->max_fds : 0);
198         rcu_read_unlock();
199
200         group_info = cred->group_info;
201         task_unlock(p);
202
203         for (g = 0; g < min(group_info->ngroups, NGROUPS_SMALL); g++)
204                 seq_printf(m, "%d ", GROUP_AT(group_info, g));
205         put_cred(cred);
206
207         seq_printf(m, "\n");
208 }
209
210 static void render_sigset_t(struct seq_file *m, const char *header,
211                                 sigset_t *set)
212 {
213         int i;
214
215         seq_printf(m, "%s", header);
216
217         i = _NSIG;
218         do {
219                 int x = 0;
220
221                 i -= 4;
222                 if (sigismember(set, i+1)) x |= 1;
223                 if (sigismember(set, i+2)) x |= 2;
224                 if (sigismember(set, i+3)) x |= 4;
225                 if (sigismember(set, i+4)) x |= 8;
226                 seq_printf(m, "%x", x);
227         } while (i >= 4);
228
229         seq_printf(m, "\n");
230 }
231
232 static void collect_sigign_sigcatch(struct task_struct *p, sigset_t *ign,
233                                     sigset_t *catch)
234 {
235         struct k_sigaction *k;
236         int i;
237
238         k = p->sighand->action;
239         for (i = 1; i <= _NSIG; ++i, ++k) {
240                 if (k->sa.sa_handler == SIG_IGN)
241                         sigaddset(ign, i);
242                 else if (k->sa.sa_handler != SIG_DFL)
243                         sigaddset(catch, i);
244         }
245 }
246
247 static inline void task_sig(struct seq_file *m, struct task_struct *p)
248 {
249         unsigned long flags;
250         sigset_t pending, shpending, blocked, ignored, caught;
251         int num_threads = 0;
252         unsigned long qsize = 0;
253         unsigned long qlim = 0;
254
255         sigemptyset(&pending);
256         sigemptyset(&shpending);
257         sigemptyset(&blocked);
258         sigemptyset(&ignored);
259         sigemptyset(&caught);
260
261         if (lock_task_sighand(p, &flags)) {
262                 pending = p->pending.signal;
263                 shpending = p->signal->shared_pending.signal;
264                 blocked = p->blocked;
265                 collect_sigign_sigcatch(p, &ignored, &caught);
266                 num_threads = atomic_read(&p->signal->count);
267                 qsize = atomic_read(&__task_cred(p)->user->sigpending);
268                 qlim = p->signal->rlim[RLIMIT_SIGPENDING].rlim_cur;
269                 unlock_task_sighand(p, &flags);
270         }
271
272         seq_printf(m, "Threads:\t%d\n", num_threads);
273         seq_printf(m, "SigQ:\t%lu/%lu\n", qsize, qlim);
274
275         /* render them all */
276         render_sigset_t(m, "SigPnd:\t", &pending);
277         render_sigset_t(m, "ShdPnd:\t", &shpending);
278         render_sigset_t(m, "SigBlk:\t", &blocked);
279         render_sigset_t(m, "SigIgn:\t", &ignored);
280         render_sigset_t(m, "SigCgt:\t", &caught);
281 }
282
283 static void render_cap_t(struct seq_file *m, const char *header,
284                         kernel_cap_t *a)
285 {
286         unsigned __capi;
287
288         seq_printf(m, "%s", header);
289         CAP_FOR_EACH_U32(__capi) {
290                 seq_printf(m, "%08x",
291                            a->cap[(_KERNEL_CAPABILITY_U32S-1) - __capi]);
292         }
293         seq_printf(m, "\n");
294 }
295
296 static inline void task_cap(struct seq_file *m, struct task_struct *p)
297 {
298         const struct cred *cred;
299         kernel_cap_t cap_inheritable, cap_permitted, cap_effective, cap_bset;
300
301         rcu_read_lock();
302         cred = __task_cred(p);
303         cap_inheritable = cred->cap_inheritable;
304         cap_permitted   = cred->cap_permitted;
305         cap_effective   = cred->cap_effective;
306         cap_bset        = cred->cap_bset;
307         rcu_read_unlock();
308
309         render_cap_t(m, "CapInh:\t", &cap_inheritable);
310         render_cap_t(m, "CapPrm:\t", &cap_permitted);
311         render_cap_t(m, "CapEff:\t", &cap_effective);
312         render_cap_t(m, "CapBnd:\t", &cap_bset);
313 }
314
315 static inline void task_context_switch_counts(struct seq_file *m,
316                                                 struct task_struct *p)
317 {
318         seq_printf(m,   "voluntary_ctxt_switches:\t%lu\n"
319                         "nonvoluntary_ctxt_switches:\t%lu\n",
320                         p->nvcsw,
321                         p->nivcsw);
322 }
323
324 int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
325                         struct pid *pid, struct task_struct *task)
326 {
327         struct mm_struct *mm = get_task_mm(task);
328
329         task_name(m, task);
330         task_state(m, ns, pid, task);
331
332         if (mm) {
333                 task_mem(m, mm);
334                 mmput(mm);
335         }
336         task_sig(m, task);
337         task_cap(m, task);
338         cpuset_task_status_allowed(m, task);
339         task_context_switch_counts(m, task);
340         return 0;
341 }
342
343 static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
344                         struct pid *pid, struct task_struct *task, int whole)
345 {
346         unsigned long vsize, eip, esp, wchan = ~0UL;
347         long priority, nice;
348         int tty_pgrp = -1, tty_nr = 0;
349         sigset_t sigign, sigcatch;
350         char state;
351         pid_t ppid = 0, pgid = -1, sid = -1;
352         int num_threads = 0;
353         int permitted;
354         struct mm_struct *mm;
355         unsigned long long start_time;
356         unsigned long cmin_flt = 0, cmaj_flt = 0;
357         unsigned long  min_flt = 0,  maj_flt = 0;
358         cputime_t cutime, cstime, utime, stime;
359         cputime_t cgtime, gtime;
360         unsigned long rsslim = 0;
361         char tcomm[sizeof(task->comm)];
362         unsigned long flags;
363
364         state = *get_task_state(task);
365         vsize = eip = esp = 0;
366         permitted = ptrace_may_access(task, PTRACE_MODE_READ);
367         mm = get_task_mm(task);
368         if (mm) {
369                 vsize = task_vsize(mm);
370                 if (permitted) {
371                         eip = KSTK_EIP(task);
372                         esp = KSTK_ESP(task);
373                 }
374         }
375
376         get_task_comm(tcomm, task);
377
378         sigemptyset(&sigign);
379         sigemptyset(&sigcatch);
380         cutime = cstime = utime = stime = cputime_zero;
381         cgtime = gtime = cputime_zero;
382
383         if (lock_task_sighand(task, &flags)) {
384                 struct signal_struct *sig = task->signal;
385
386                 if (sig->tty) {
387                         struct pid *pgrp = tty_get_pgrp(sig->tty);
388                         tty_pgrp = pid_nr_ns(pgrp, ns);
389                         put_pid(pgrp);
390                         tty_nr = new_encode_dev(tty_devnum(sig->tty));
391                 }
392
393                 num_threads = atomic_read(&sig->count);
394                 collect_sigign_sigcatch(task, &sigign, &sigcatch);
395
396                 cmin_flt = sig->cmin_flt;
397                 cmaj_flt = sig->cmaj_flt;
398                 cutime = sig->cutime;
399                 cstime = sig->cstime;
400                 cgtime = sig->cgtime;
401                 rsslim = sig->rlim[RLIMIT_RSS].rlim_cur;
402
403                 /* add up live thread stats at the group level */
404                 if (whole) {
405                         struct task_struct *t = task;
406                         do {
407                                 min_flt += t->min_flt;
408                                 maj_flt += t->maj_flt;
409                                 gtime = cputime_add(gtime, task_gtime(t));
410                                 t = next_thread(t);
411                         } while (t != task);
412
413                         min_flt += sig->min_flt;
414                         maj_flt += sig->maj_flt;
415                         thread_group_times(task, &utime, &stime);
416                         gtime = cputime_add(gtime, sig->gtime);
417                 }
418
419                 sid = task_session_nr_ns(task, ns);
420                 ppid = task_tgid_nr_ns(task->real_parent, ns);
421                 pgid = task_pgrp_nr_ns(task, ns);
422
423                 unlock_task_sighand(task, &flags);
424         }
425
426         if (permitted && (!whole || num_threads < 2))
427                 wchan = get_wchan(task);
428         if (!whole) {
429                 min_flt = task->min_flt;
430                 maj_flt = task->maj_flt;
431                 utime = task_utime(task);
432                 stime = task_stime(task);
433                 gtime = task_gtime(task);
434         }
435
436         /* scale priority and nice values from timeslices to -20..20 */
437         /* to make it look like a "normal" Unix priority/nice value  */
438         priority = task_prio(task);
439         nice = task_nice(task);
440
441         /* Temporary variable needed for gcc-2.96 */
442         /* convert timespec -> nsec*/
443         start_time =
444                 (unsigned long long)task->real_start_time.tv_sec * NSEC_PER_SEC
445                                 + task->real_start_time.tv_nsec;
446         /* convert nsec -> ticks */
447         start_time = nsec_to_clock_t(start_time);
448
449         seq_printf(m, "%d (%s) %c %d %d %d %d %d %u %lu \
450 %lu %lu %lu %lu %lu %ld %ld %ld %ld %d 0 %llu %lu %ld %lu %lu %lu %lu %lu \
451 %lu %lu %lu %lu %lu %lu %lu %lu %d %d %u %u %llu %lu %ld\n",
452                 pid_nr_ns(pid, ns),
453                 tcomm,
454                 state,
455                 ppid,
456                 pgid,
457                 sid,
458                 tty_nr,
459                 tty_pgrp,
460                 task->flags,
461                 min_flt,
462                 cmin_flt,
463                 maj_flt,
464                 cmaj_flt,
465                 cputime_to_clock_t(utime),
466                 cputime_to_clock_t(stime),
467                 cputime_to_clock_t(cutime),
468                 cputime_to_clock_t(cstime),
469                 priority,
470                 nice,
471                 num_threads,
472                 start_time,
473                 vsize,
474                 mm ? get_mm_rss(mm) : 0,
475                 rsslim,
476                 mm ? (permitted ? mm->start_code : 1) : 0,
477                 mm ? (permitted ? mm->end_code : 1) : 0,
478                 (permitted && mm) ? mm->start_stack : 0,
479                 esp,
480                 eip,
481                 /* The signal information here is obsolete.
482                  * It must be decimal for Linux 2.0 compatibility.
483                  * Use /proc/#/status for real-time signals.
484                  */
485                 task->pending.signal.sig[0] & 0x7fffffffUL,
486                 task->blocked.sig[0] & 0x7fffffffUL,
487                 sigign      .sig[0] & 0x7fffffffUL,
488                 sigcatch    .sig[0] & 0x7fffffffUL,
489                 wchan,
490                 0UL,
491                 0UL,
492                 task->exit_signal,
493                 task_cpu(task),
494                 task->rt_priority,
495                 task->policy,
496                 (unsigned long long)delayacct_blkio_ticks(task),
497                 cputime_to_clock_t(gtime),
498                 cputime_to_clock_t(cgtime));
499         if (mm)
500                 mmput(mm);
501         return 0;
502 }
503
504 int proc_tid_stat(struct seq_file *m, struct pid_namespace *ns,
505                         struct pid *pid, struct task_struct *task)
506 {
507         return do_task_stat(m, ns, pid, task, 0);
508 }
509
510 int proc_tgid_stat(struct seq_file *m, struct pid_namespace *ns,
511                         struct pid *pid, struct task_struct *task)
512 {
513         return do_task_stat(m, ns, pid, task, 1);
514 }
515
516 int proc_pid_statm(struct seq_file *m, struct pid_namespace *ns,
517                         struct pid *pid, struct task_struct *task)
518 {
519         int size = 0, resident = 0, shared = 0, text = 0, lib = 0, data = 0;
520         struct mm_struct *mm = get_task_mm(task);
521
522         if (mm) {
523                 size = task_statm(mm, &shared, &text, &data, &resident);
524                 mmput(mm);
525         }
526         seq_printf(m, "%d %d %d %d %d %d %d\n",
527                         size, resident, shared, text, lib, data, 0);
528
529         return 0;
530 }