1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * linux/fs/proc/array.c 4 * 5 * Copyright (C) 1992 by Linus Torvalds 6 * based on ideas by Darren Senn 7 * 8 * Fixes: 9 * Michael. K. Johnson: stat,statm extensions. 10 * <johnsonm@stolaf.edu> 11 * 12 * Pauline Middelink : Made cmdline,envline only break at '\0's, to 13 * make sure SET_PROCTITLE works. Also removed 14 * bad '!' which forced address recalculation for 15 * EVERY character on the current page. 16 * <middelin@polyware.iaf.nl> 17 * 18 * Danny ter Haar : added cpuinfo 19 * <dth@cistron.nl> 20 * 21 * Alessandro Rubini : profile extension. 22 * <rubini@ipvvis.unipv.it> 23 * 24 * Jeff Tranter : added BogoMips field to cpuinfo 25 * <Jeff_Tranter@Mitel.COM> 26 * 27 * Bruno Haible : remove 4K limit for the maps file 28 * <haible@ma2s2.mathematik.uni-karlsruhe.de> 29 * 30 * Yves Arrouye : remove removal of trailing spaces in get_array. 31 * <Yves.Arrouye@marin.fdn.fr> 32 * 33 * Jerome Forissier : added per-CPU time information to /proc/stat 34 * and /proc/<pid>/cpu extension 35 * <forissier@isia.cma.fr> 36 * - Incorporation and non-SMP safe operation 37 * of forissier patch in 2.1.78 by 38 * Hans Marcus <crowbar@concepts.nl> 39 * 40 * aeb@cwi.nl : /proc/partitions 41 * 42 * 43 * Alan Cox : security fixes. 44 * <alan@lxorguk.ukuu.org.uk> 45 * 46 * Al Viro : safe handling of mm_struct 47 * 48 * Gerhard Wichert : added BIGMEM support 49 * Siemens AG <Gerhard.Wichert@pdb.siemens.de> 50 * 51 * Al Viro & Jeff Garzik : moved most of the thing into base.c and 52 * : proc_misc.c. The rest may eventually go into 53 * : base.c too. 54 */ 55 56 #include <linux/types.h> 57 #include <linux/errno.h> 58 #include <linux/time.h> 59 #include <linux/kernel.h> 60 #include <linux/kernel_stat.h> 61 #include <linux/tty.h> 62 #include <linux/string.h> 63 #include <linux/mman.h> 64 #include <linux/sched/mm.h> 65 #include <linux/sched/numa_balancing.h> 66 #include <linux/sched/task_stack.h> 67 #include <linux/sched/task.h> 68 #include <linux/sched/cputime.h> 69 #include <linux/proc_fs.h> 70 #include <linux/ioport.h> 71 #include <linux/uaccess.h> 72 #include <linux/io.h> 73 #include <linux/mm.h> 74 #include <linux/hugetlb.h> 75 #include <linux/pagemap.h> 76 #include <linux/swap.h> 77 #include <linux/smp.h> 78 #include <linux/signal.h> 79 #include <linux/highmem.h> 80 #include <linux/file.h> 81 #include <linux/fdtable.h> 82 #include <linux/times.h> 83 #include <linux/cpuset.h> 84 #include <linux/rcupdate.h> 85 #include <linux/delayacct.h> 86 #include <linux/seq_file.h> 87 #include <linux/pid_namespace.h> 88 #include <linux/prctl.h> 89 #include <linux/ptrace.h> 90 #include <linux/tracehook.h> 91 #include <linux/string_helpers.h> 92 #include <linux/user_namespace.h> 93 #include <linux/fs_struct.h> 94 95 #include <asm/pgtable.h> 96 #include <asm/processor.h> 97 #include "internal.h" 98 99 static inline void task_name(struct seq_file *m, struct task_struct *p) 100 { 101 char *buf; 102 size_t size; 103 char tcomm[sizeof(p->comm)]; 104 int ret; 105 106 get_task_comm(tcomm, p); 107 108 seq_puts(m, "Name:\t"); 109 110 size = seq_get_buf(m, &buf); 111 ret = string_escape_str(tcomm, buf, size, ESCAPE_SPACE | ESCAPE_SPECIAL, "\n\\"); 112 seq_commit(m, ret < size ? ret : -1); 113 114 seq_putc(m, '\n'); 115 } 116 117 /* 118 * The task state array is a strange "bitmap" of 119 * reasons to sleep. Thus "running" is zero, and 120 * you can test for combinations of others with 121 * simple bit tests. 122 */ 123 static const char * const task_state_array[] = { 124 125 /* states in TASK_REPORT: */ 126 "R (running)", /* 0x00 */ 127 "S (sleeping)", /* 0x01 */ 128 "D (disk sleep)", /* 0x02 */ 129 "T (stopped)", /* 0x04 */ 130 "t (tracing stop)", /* 0x08 */ 131 "X (dead)", /* 0x10 */ 132 "Z (zombie)", /* 0x20 */ 133 "P (parked)", /* 0x40 */ 134 135 /* states beyond TASK_REPORT: */ 136 "I (idle)", /* 0x80 */ 137 }; 138 139 static inline const char *get_task_state(struct task_struct *tsk) 140 { 141 BUILD_BUG_ON(1 + ilog2(TASK_REPORT_MAX) != ARRAY_SIZE(task_state_array)); 142 return task_state_array[task_state_index(tsk)]; 143 } 144 145 static inline void task_state(struct seq_file *m, struct pid_namespace *ns, 146 struct pid *pid, struct task_struct *p) 147 { 148 struct user_namespace *user_ns = seq_user_ns(m); 149 struct group_info *group_info; 150 int g, umask = -1; 151 struct task_struct *tracer; 152 const struct cred *cred; 153 pid_t ppid, tpid = 0, tgid, ngid; 154 unsigned int max_fds = 0; 155 156 rcu_read_lock(); 157 ppid = pid_alive(p) ? 158 task_tgid_nr_ns(rcu_dereference(p->real_parent), ns) : 0; 159 160 tracer = ptrace_parent(p); 161 if (tracer) 162 tpid = task_pid_nr_ns(tracer, ns); 163 164 tgid = task_tgid_nr_ns(p, ns); 165 ngid = task_numa_group_id(p); 166 cred = get_task_cred(p); 167 168 task_lock(p); 169 if (p->fs) 170 umask = p->fs->umask; 171 if (p->files) 172 max_fds = files_fdtable(p->files)->max_fds; 173 task_unlock(p); 174 rcu_read_unlock(); 175 176 if (umask >= 0) 177 seq_printf(m, "Umask:\t%#04o\n", umask); 178 seq_puts(m, "State:\t"); 179 seq_puts(m, get_task_state(p)); 180 181 seq_put_decimal_ull(m, "\nTgid:\t", tgid); 182 seq_put_decimal_ull(m, "\nNgid:\t", ngid); 183 seq_put_decimal_ull(m, "\nPid:\t", pid_nr_ns(pid, ns)); 184 seq_put_decimal_ull(m, "\nPPid:\t", ppid); 185 seq_put_decimal_ull(m, "\nTracerPid:\t", tpid); 186 seq_put_decimal_ull(m, "\nUid:\t", from_kuid_munged(user_ns, cred->uid)); 187 seq_put_decimal_ull(m, "\t", from_kuid_munged(user_ns, cred->euid)); 188 seq_put_decimal_ull(m, "\t", from_kuid_munged(user_ns, cred->suid)); 189 seq_put_decimal_ull(m, "\t", from_kuid_munged(user_ns, cred->fsuid)); 190 seq_put_decimal_ull(m, "\nGid:\t", from_kgid_munged(user_ns, cred->gid)); 191 seq_put_decimal_ull(m, "\t", from_kgid_munged(user_ns, cred->egid)); 192 seq_put_decimal_ull(m, "\t", from_kgid_munged(user_ns, cred->sgid)); 193 seq_put_decimal_ull(m, "\t", from_kgid_munged(user_ns, cred->fsgid)); 194 seq_put_decimal_ull(m, "\nFDSize:\t", max_fds); 195 196 seq_puts(m, "\nGroups:\t"); 197 group_info = cred->group_info; 198 for (g = 0; g < group_info->ngroups; g++) 199 seq_put_decimal_ull(m, g ? " " : "", 200 from_kgid_munged(user_ns, group_info->gid[g])); 201 put_cred(cred); 202 /* Trailing space shouldn't have been added in the first place. */ 203 seq_putc(m, ' '); 204 205 #ifdef CONFIG_PID_NS 206 seq_puts(m, "\nNStgid:"); 207 for (g = ns->level; g <= pid->level; g++) 208 seq_put_decimal_ull(m, "\t", task_tgid_nr_ns(p, pid->numbers[g].ns)); 209 seq_puts(m, "\nNSpid:"); 210 for (g = ns->level; g <= pid->level; g++) 211 seq_put_decimal_ull(m, "\t", task_pid_nr_ns(p, pid->numbers[g].ns)); 212 seq_puts(m, "\nNSpgid:"); 213 for (g = ns->level; g <= pid->level; g++) 214 seq_put_decimal_ull(m, "\t", task_pgrp_nr_ns(p, pid->numbers[g].ns)); 215 seq_puts(m, "\nNSsid:"); 216 for (g = ns->level; g <= pid->level; g++) 217 seq_put_decimal_ull(m, "\t", task_session_nr_ns(p, pid->numbers[g].ns)); 218 #endif 219 seq_putc(m, '\n'); 220 } 221 222 void render_sigset_t(struct seq_file *m, const char *header, 223 sigset_t *set) 224 { 225 int i; 226 227 seq_puts(m, header); 228 229 i = _NSIG; 230 do { 231 int x = 0; 232 233 i -= 4; 234 if (sigismember(set, i+1)) x |= 1; 235 if (sigismember(set, i+2)) x |= 2; 236 if (sigismember(set, i+3)) x |= 4; 237 if (sigismember(set, i+4)) x |= 8; 238 seq_putc(m, hex_asc[x]); 239 } while (i >= 4); 240 241 seq_putc(m, '\n'); 242 } 243 244 static void collect_sigign_sigcatch(struct task_struct *p, sigset_t *ign, 245 sigset_t *catch) 246 { 247 struct k_sigaction *k; 248 int i; 249 250 k = p->sighand->action; 251 for (i = 1; i <= _NSIG; ++i, ++k) { 252 if (k->sa.sa_handler == SIG_IGN) 253 sigaddset(ign, i); 254 else if (k->sa.sa_handler != SIG_DFL) 255 sigaddset(catch, i); 256 } 257 } 258 259 static inline void task_sig(struct seq_file *m, struct task_struct *p) 260 { 261 unsigned long flags; 262 sigset_t pending, shpending, blocked, ignored, caught; 263 int num_threads = 0; 264 unsigned long qsize = 0; 265 unsigned long qlim = 0; 266 267 sigemptyset(&pending); 268 sigemptyset(&shpending); 269 sigemptyset(&blocked); 270 sigemptyset(&ignored); 271 sigemptyset(&caught); 272 273 if (lock_task_sighand(p, &flags)) { 274 pending = p->pending.signal; 275 shpending = p->signal->shared_pending.signal; 276 blocked = p->blocked; 277 collect_sigign_sigcatch(p, &ignored, &caught); 278 num_threads = get_nr_threads(p); 279 rcu_read_lock(); /* FIXME: is this correct? */ 280 qsize = atomic_read(&__task_cred(p)->user->sigpending); 281 rcu_read_unlock(); 282 qlim = task_rlimit(p, RLIMIT_SIGPENDING); 283 unlock_task_sighand(p, &flags); 284 } 285 286 seq_put_decimal_ull(m, "Threads:\t", num_threads); 287 seq_put_decimal_ull(m, "\nSigQ:\t", qsize); 288 seq_put_decimal_ull(m, "/", qlim); 289 290 /* render them all */ 291 render_sigset_t(m, "\nSigPnd:\t", &pending); 292 render_sigset_t(m, "ShdPnd:\t", &shpending); 293 render_sigset_t(m, "SigBlk:\t", &blocked); 294 render_sigset_t(m, "SigIgn:\t", &ignored); 295 render_sigset_t(m, "SigCgt:\t", &caught); 296 } 297 298 static void render_cap_t(struct seq_file *m, const char *header, 299 kernel_cap_t *a) 300 { 301 unsigned __capi; 302 303 seq_puts(m, header); 304 CAP_FOR_EACH_U32(__capi) { 305 seq_put_hex_ll(m, NULL, 306 a->cap[CAP_LAST_U32 - __capi], 8); 307 } 308 seq_putc(m, '\n'); 309 } 310 311 static inline void task_cap(struct seq_file *m, struct task_struct *p) 312 { 313 const struct cred *cred; 314 kernel_cap_t cap_inheritable, cap_permitted, cap_effective, 315 cap_bset, cap_ambient; 316 317 rcu_read_lock(); 318 cred = __task_cred(p); 319 cap_inheritable = cred->cap_inheritable; 320 cap_permitted = cred->cap_permitted; 321 cap_effective = cred->cap_effective; 322 cap_bset = cred->cap_bset; 323 cap_ambient = cred->cap_ambient; 324 rcu_read_unlock(); 325 326 render_cap_t(m, "CapInh:\t", &cap_inheritable); 327 render_cap_t(m, "CapPrm:\t", &cap_permitted); 328 render_cap_t(m, "CapEff:\t", &cap_effective); 329 render_cap_t(m, "CapBnd:\t", &cap_bset); 330 render_cap_t(m, "CapAmb:\t", &cap_ambient); 331 } 332 333 static inline void task_seccomp(struct seq_file *m, struct task_struct *p) 334 { 335 seq_put_decimal_ull(m, "NoNewPrivs:\t", task_no_new_privs(p)); 336 #ifdef CONFIG_SECCOMP 337 seq_put_decimal_ull(m, "\nSeccomp:\t", p->seccomp.mode); 338 #endif 339 seq_printf(m, "\nSpeculation Store Bypass:\t"); 340 switch (arch_prctl_spec_ctrl_get(p, PR_SPEC_STORE_BYPASS)) { 341 case -EINVAL: 342 seq_printf(m, "unknown"); 343 break; 344 case PR_SPEC_NOT_AFFECTED: 345 seq_printf(m, "not vulnerable"); 346 break; 347 case PR_SPEC_PRCTL | PR_SPEC_DISABLE: 348 seq_printf(m, "thread mitigated"); 349 break; 350 case PR_SPEC_PRCTL | PR_SPEC_ENABLE: 351 seq_printf(m, "thread vulnerable"); 352 break; 353 case PR_SPEC_DISABLE: 354 seq_printf(m, "globally mitigated"); 355 break; 356 default: 357 seq_printf(m, "vulnerable"); 358 break; 359 } 360 seq_putc(m, '\n'); 361 } 362 363 static inline void task_context_switch_counts(struct seq_file *m, 364 struct task_struct *p) 365 { 366 seq_put_decimal_ull(m, "voluntary_ctxt_switches:\t", p->nvcsw); 367 seq_put_decimal_ull(m, "\nnonvoluntary_ctxt_switches:\t", p->nivcsw); 368 seq_putc(m, '\n'); 369 } 370 371 static void task_cpus_allowed(struct seq_file *m, struct task_struct *task) 372 { 373 seq_printf(m, "Cpus_allowed:\t%*pb\n", 374 cpumask_pr_args(&task->cpus_allowed)); 375 seq_printf(m, "Cpus_allowed_list:\t%*pbl\n", 376 cpumask_pr_args(&task->cpus_allowed)); 377 } 378 379 static inline void task_core_dumping(struct seq_file *m, struct mm_struct *mm) 380 { 381 seq_put_decimal_ull(m, "CoreDumping:\t", !!mm->core_state); 382 seq_putc(m, '\n'); 383 } 384 385 int proc_pid_status(struct seq_file *m, struct pid_namespace *ns, 386 struct pid *pid, struct task_struct *task) 387 { 388 struct mm_struct *mm = get_task_mm(task); 389 390 task_name(m, task); 391 task_state(m, ns, pid, task); 392 393 if (mm) { 394 task_mem(m, mm); 395 task_core_dumping(m, mm); 396 mmput(mm); 397 } 398 task_sig(m, task); 399 task_cap(m, task); 400 task_seccomp(m, task); 401 task_cpus_allowed(m, task); 402 cpuset_task_status_allowed(m, task); 403 task_context_switch_counts(m, task); 404 return 0; 405 } 406 407 static int do_task_stat(struct seq_file *m, struct pid_namespace *ns, 408 struct pid *pid, struct task_struct *task, int whole) 409 { 410 unsigned long vsize, eip, esp, wchan = 0; 411 int priority, nice; 412 int tty_pgrp = -1, tty_nr = 0; 413 sigset_t sigign, sigcatch; 414 char state; 415 pid_t ppid = 0, pgid = -1, sid = -1; 416 int num_threads = 0; 417 int permitted; 418 struct mm_struct *mm; 419 unsigned long long start_time; 420 unsigned long cmin_flt = 0, cmaj_flt = 0; 421 unsigned long min_flt = 0, maj_flt = 0; 422 u64 cutime, cstime, utime, stime; 423 u64 cgtime, gtime; 424 unsigned long rsslim = 0; 425 char tcomm[sizeof(task->comm)]; 426 unsigned long flags; 427 428 state = *get_task_state(task); 429 vsize = eip = esp = 0; 430 permitted = ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS | PTRACE_MODE_NOAUDIT); 431 mm = get_task_mm(task); 432 if (mm) { 433 vsize = task_vsize(mm); 434 /* 435 * esp and eip are intentionally zeroed out. There is no 436 * non-racy way to read them without freezing the task. 437 * Programs that need reliable values can use ptrace(2). 438 * 439 * The only exception is if the task is core dumping because 440 * a program is not able to use ptrace(2) in that case. It is 441 * safe because the task has stopped executing permanently. 442 */ 443 if (permitted && (task->flags & PF_DUMPCORE)) { 444 if (try_get_task_stack(task)) { 445 eip = KSTK_EIP(task); 446 esp = KSTK_ESP(task); 447 put_task_stack(task); 448 } 449 } 450 } 451 452 get_task_comm(tcomm, task); 453 454 sigemptyset(&sigign); 455 sigemptyset(&sigcatch); 456 cutime = cstime = utime = stime = 0; 457 cgtime = gtime = 0; 458 459 if (lock_task_sighand(task, &flags)) { 460 struct signal_struct *sig = task->signal; 461 462 if (sig->tty) { 463 struct pid *pgrp = tty_get_pgrp(sig->tty); 464 tty_pgrp = pid_nr_ns(pgrp, ns); 465 put_pid(pgrp); 466 tty_nr = new_encode_dev(tty_devnum(sig->tty)); 467 } 468 469 num_threads = get_nr_threads(task); 470 collect_sigign_sigcatch(task, &sigign, &sigcatch); 471 472 cmin_flt = sig->cmin_flt; 473 cmaj_flt = sig->cmaj_flt; 474 cutime = sig->cutime; 475 cstime = sig->cstime; 476 cgtime = sig->cgtime; 477 rsslim = READ_ONCE(sig->rlim[RLIMIT_RSS].rlim_cur); 478 479 /* add up live thread stats at the group level */ 480 if (whole) { 481 struct task_struct *t = task; 482 do { 483 min_flt += t->min_flt; 484 maj_flt += t->maj_flt; 485 gtime += task_gtime(t); 486 } while_each_thread(task, t); 487 488 min_flt += sig->min_flt; 489 maj_flt += sig->maj_flt; 490 thread_group_cputime_adjusted(task, &utime, &stime); 491 gtime += sig->gtime; 492 } 493 494 sid = task_session_nr_ns(task, ns); 495 ppid = task_tgid_nr_ns(task->real_parent, ns); 496 pgid = task_pgrp_nr_ns(task, ns); 497 498 unlock_task_sighand(task, &flags); 499 } 500 501 if (permitted && (!whole || num_threads < 2)) 502 wchan = get_wchan(task); 503 if (!whole) { 504 min_flt = task->min_flt; 505 maj_flt = task->maj_flt; 506 task_cputime_adjusted(task, &utime, &stime); 507 gtime = task_gtime(task); 508 } 509 510 /* scale priority and nice values from timeslices to -20..20 */ 511 /* to make it look like a "normal" Unix priority/nice value */ 512 priority = task_prio(task); 513 nice = task_nice(task); 514 515 /* convert nsec -> ticks */ 516 start_time = nsec_to_clock_t(task->real_start_time); 517 518 seq_put_decimal_ull(m, "", pid_nr_ns(pid, ns)); 519 seq_puts(m, " ("); 520 seq_puts(m, tcomm); 521 seq_puts(m, ") "); 522 seq_putc(m, state); 523 seq_put_decimal_ll(m, " ", ppid); 524 seq_put_decimal_ll(m, " ", pgid); 525 seq_put_decimal_ll(m, " ", sid); 526 seq_put_decimal_ll(m, " ", tty_nr); 527 seq_put_decimal_ll(m, " ", tty_pgrp); 528 seq_put_decimal_ull(m, " ", task->flags); 529 seq_put_decimal_ull(m, " ", min_flt); 530 seq_put_decimal_ull(m, " ", cmin_flt); 531 seq_put_decimal_ull(m, " ", maj_flt); 532 seq_put_decimal_ull(m, " ", cmaj_flt); 533 seq_put_decimal_ull(m, " ", nsec_to_clock_t(utime)); 534 seq_put_decimal_ull(m, " ", nsec_to_clock_t(stime)); 535 seq_put_decimal_ll(m, " ", nsec_to_clock_t(cutime)); 536 seq_put_decimal_ll(m, " ", nsec_to_clock_t(cstime)); 537 seq_put_decimal_ll(m, " ", priority); 538 seq_put_decimal_ll(m, " ", nice); 539 seq_put_decimal_ll(m, " ", num_threads); 540 seq_put_decimal_ull(m, " ", 0); 541 seq_put_decimal_ull(m, " ", start_time); 542 seq_put_decimal_ull(m, " ", vsize); 543 seq_put_decimal_ull(m, " ", mm ? get_mm_rss(mm) : 0); 544 seq_put_decimal_ull(m, " ", rsslim); 545 seq_put_decimal_ull(m, " ", mm ? (permitted ? mm->start_code : 1) : 0); 546 seq_put_decimal_ull(m, " ", mm ? (permitted ? mm->end_code : 1) : 0); 547 seq_put_decimal_ull(m, " ", (permitted && mm) ? mm->start_stack : 0); 548 seq_put_decimal_ull(m, " ", esp); 549 seq_put_decimal_ull(m, " ", eip); 550 /* The signal information here is obsolete. 551 * It must be decimal for Linux 2.0 compatibility. 552 * Use /proc/#/status for real-time signals. 553 */ 554 seq_put_decimal_ull(m, " ", task->pending.signal.sig[0] & 0x7fffffffUL); 555 seq_put_decimal_ull(m, " ", task->blocked.sig[0] & 0x7fffffffUL); 556 seq_put_decimal_ull(m, " ", sigign.sig[0] & 0x7fffffffUL); 557 seq_put_decimal_ull(m, " ", sigcatch.sig[0] & 0x7fffffffUL); 558 559 /* 560 * We used to output the absolute kernel address, but that's an 561 * information leak - so instead we show a 0/1 flag here, to signal 562 * to user-space whether there's a wchan field in /proc/PID/wchan. 563 * 564 * This works with older implementations of procps as well. 565 */ 566 if (wchan) 567 seq_puts(m, " 1"); 568 else 569 seq_puts(m, " 0"); 570 571 seq_put_decimal_ull(m, " ", 0); 572 seq_put_decimal_ull(m, " ", 0); 573 seq_put_decimal_ll(m, " ", task->exit_signal); 574 seq_put_decimal_ll(m, " ", task_cpu(task)); 575 seq_put_decimal_ull(m, " ", task->rt_priority); 576 seq_put_decimal_ull(m, " ", task->policy); 577 seq_put_decimal_ull(m, " ", delayacct_blkio_ticks(task)); 578 seq_put_decimal_ull(m, " ", nsec_to_clock_t(gtime)); 579 seq_put_decimal_ll(m, " ", nsec_to_clock_t(cgtime)); 580 581 if (mm && permitted) { 582 seq_put_decimal_ull(m, " ", mm->start_data); 583 seq_put_decimal_ull(m, " ", mm->end_data); 584 seq_put_decimal_ull(m, " ", mm->start_brk); 585 seq_put_decimal_ull(m, " ", mm->arg_start); 586 seq_put_decimal_ull(m, " ", mm->arg_end); 587 seq_put_decimal_ull(m, " ", mm->env_start); 588 seq_put_decimal_ull(m, " ", mm->env_end); 589 } else 590 seq_puts(m, " 0 0 0 0 0 0 0"); 591 592 if (permitted) 593 seq_put_decimal_ll(m, " ", task->exit_code); 594 else 595 seq_puts(m, " 0"); 596 597 seq_putc(m, '\n'); 598 if (mm) 599 mmput(mm); 600 return 0; 601 } 602 603 int proc_tid_stat(struct seq_file *m, struct pid_namespace *ns, 604 struct pid *pid, struct task_struct *task) 605 { 606 return do_task_stat(m, ns, pid, task, 0); 607 } 608 609 int proc_tgid_stat(struct seq_file *m, struct pid_namespace *ns, 610 struct pid *pid, struct task_struct *task) 611 { 612 return do_task_stat(m, ns, pid, task, 1); 613 } 614 615 int proc_pid_statm(struct seq_file *m, struct pid_namespace *ns, 616 struct pid *pid, struct task_struct *task) 617 { 618 unsigned long size = 0, resident = 0, shared = 0, text = 0, data = 0; 619 struct mm_struct *mm = get_task_mm(task); 620 621 if (mm) { 622 size = task_statm(mm, &shared, &text, &data, &resident); 623 mmput(mm); 624 } 625 /* 626 * For quick read, open code by putting numbers directly 627 * expected format is 628 * seq_printf(m, "%lu %lu %lu %lu 0 %lu 0\n", 629 * size, resident, shared, text, data); 630 */ 631 seq_put_decimal_ull(m, "", size); 632 seq_put_decimal_ull(m, " ", resident); 633 seq_put_decimal_ull(m, " ", shared); 634 seq_put_decimal_ull(m, " ", text); 635 seq_put_decimal_ull(m, " ", 0); 636 seq_put_decimal_ull(m, " ", data); 637 seq_put_decimal_ull(m, " ", 0); 638 seq_putc(m, '\n'); 639 640 return 0; 641 } 642 643 #ifdef CONFIG_PROC_CHILDREN 644 static struct pid * 645 get_children_pid(struct inode *inode, struct pid *pid_prev, loff_t pos) 646 { 647 struct task_struct *start, *task; 648 struct pid *pid = NULL; 649 650 read_lock(&tasklist_lock); 651 652 start = pid_task(proc_pid(inode), PIDTYPE_PID); 653 if (!start) 654 goto out; 655 656 /* 657 * Lets try to continue searching first, this gives 658 * us significant speedup on children-rich processes. 659 */ 660 if (pid_prev) { 661 task = pid_task(pid_prev, PIDTYPE_PID); 662 if (task && task->real_parent == start && 663 !(list_empty(&task->sibling))) { 664 if (list_is_last(&task->sibling, &start->children)) 665 goto out; 666 task = list_first_entry(&task->sibling, 667 struct task_struct, sibling); 668 pid = get_pid(task_pid(task)); 669 goto out; 670 } 671 } 672 673 /* 674 * Slow search case. 675 * 676 * We might miss some children here if children 677 * are exited while we were not holding the lock, 678 * but it was never promised to be accurate that 679 * much. 680 * 681 * "Just suppose that the parent sleeps, but N children 682 * exit after we printed their tids. Now the slow paths 683 * skips N extra children, we miss N tasks." (c) 684 * 685 * So one need to stop or freeze the leader and all 686 * its children to get a precise result. 687 */ 688 list_for_each_entry(task, &start->children, sibling) { 689 if (pos-- == 0) { 690 pid = get_pid(task_pid(task)); 691 break; 692 } 693 } 694 695 out: 696 read_unlock(&tasklist_lock); 697 return pid; 698 } 699 700 static int children_seq_show(struct seq_file *seq, void *v) 701 { 702 struct inode *inode = seq->private; 703 pid_t pid; 704 705 pid = pid_nr_ns(v, inode->i_sb->s_fs_info); 706 seq_printf(seq, "%d ", pid); 707 708 return 0; 709 } 710 711 static void *children_seq_start(struct seq_file *seq, loff_t *pos) 712 { 713 return get_children_pid(seq->private, NULL, *pos); 714 } 715 716 static void *children_seq_next(struct seq_file *seq, void *v, loff_t *pos) 717 { 718 struct pid *pid; 719 720 pid = get_children_pid(seq->private, v, *pos + 1); 721 put_pid(v); 722 723 ++*pos; 724 return pid; 725 } 726 727 static void children_seq_stop(struct seq_file *seq, void *v) 728 { 729 put_pid(v); 730 } 731 732 static const struct seq_operations children_seq_ops = { 733 .start = children_seq_start, 734 .next = children_seq_next, 735 .stop = children_seq_stop, 736 .show = children_seq_show, 737 }; 738 739 static int children_seq_open(struct inode *inode, struct file *file) 740 { 741 struct seq_file *m; 742 int ret; 743 744 ret = seq_open(file, &children_seq_ops); 745 if (ret) 746 return ret; 747 748 m = file->private_data; 749 m->private = inode; 750 751 return ret; 752 } 753 754 const struct file_operations proc_tid_children_operations = { 755 .open = children_seq_open, 756 .read = seq_read, 757 .llseek = seq_lseek, 758 .release = seq_release, 759 }; 760 #endif /* CONFIG_PROC_CHILDREN */ 761