/*
   *  linux/fs/proc/array.c
   *
   *  Copyright (C) 1992  by Linus Torvalds
   *  based on ideas by Darren Senn
   *
   * Fixes:
   * Michael. K. Johnson: stat,statm extensions.
   *                      <johnsonm@stolaf.edu>
   *
   * Pauline Middelink :  Made cmdline,envline only break at '\0's, to
   *                      make sure SET_PROCTITLE works. Also removed
   *                      bad '!' which forced address recalculation for
   *                      EVERY character on the current page.
   *                      <middelin@polyware.iaf.nl>
   *
   * Danny ter Haar    :	added cpuinfo
   *			<dth@cistron.nl>
   *
   * Alessandro Rubini :  profile extension.
   *                      <rubini@ipvvis.unipv.it>
   *
   * Jeff Tranter      :  added BogoMips field to cpuinfo
   *                      <Jeff_Tranter@Mitel.COM>
   *
   * Bruno Haible      :  remove 4K limit for the maps file
   *			<haible@ma2s2.mathematik.uni-karlsruhe.de>
   *
   * Yves Arrouye      :  remove removal of trailing spaces in get_array.
   *			<Yves.Arrouye@marin.fdn.fr>
   *
   * Jerome Forissier  :  added per-CPU time information to /proc/stat
   *                      and /proc/<pid>/cpu extension
   *                      <forissier@isia.cma.fr>
   *			- Incorporation and non-SMP safe operation
   *			of forissier patch in 2.1.78 by
   *			Hans Marcus <crowbar@concepts.nl>
   *
   * aeb@cwi.nl        :  /proc/partitions
   *
   *
   * Alan Cox	     :  security fixes.

   *			<alan@lxorguk.ukuu.org.uk>

   *
   * Al Viro           :  safe handling of mm_struct
   *
   * Gerhard Wichert   :  added BIGMEM support
   * Siemens AG           <Gerhard.Wichert@pdb.siemens.de>
   *
   * Al Viro & Jeff Garzik :  moved most of the thing into base.c and
   *			 :  proc_misc.c. The rest may eventually go into
   *			 :  base.c too.
   */

  #include <linux/types.h>
  #include <linux/errno.h>
  #include <linux/time.h>
  #include <linux/kernel.h>
  #include <linux/kernel_stat.h>
  #include <linux/tty.h>
  #include <linux/string.h>
  #include <linux/mman.h>
  #include <linux/proc_fs.h>
  #include <linux/ioport.h>

  #include <linux/uaccess.h>
  #include <linux/io.h>

  #include <linux/mm.h>
  #include <linux/hugetlb.h>
  #include <linux/pagemap.h>
  #include <linux/swap.h>

  #include <linux/smp.h>
  #include <linux/signal.h>
  #include <linux/highmem.h>
  #include <linux/file.h>

  #include <linux/fdtable.h>

  #include <linux/times.h>
  #include <linux/cpuset.h>

  #include <linux/rcupdate.h>

  #include <linux/delayacct.h>

  #include <linux/seq_file.h>

  #include <linux/pid_namespace.h>

  #include <linux/ptrace.h>

  #include <linux/tracehook.h>

  #include <asm/pgtable.h>

  #include <asm/processor.h>
  #include "internal.h"

  static inline void task_name(struct seq_file *m, struct task_struct *p)

  {
  	int i;

  	char *buf, *end;

  	char *name;

  	char tcomm[sizeof(p->comm)];
  
  	get_task_comm(tcomm, p);

  	seq_puts(m, "Name:\t");

  	end = m->buf + m->size;
  	buf = m->buf + m->count;

  	name = tcomm;
  	i = sizeof(tcomm);

  	while (i && (buf < end)) {

  		unsigned char c = *name;
  		name++;
  		i--;
  		*buf = c;
  		if (!c)
  			break;
  		if (c == '\\') {

  			buf++;
  			if (buf < end)
  				*buf++ = c;

  			continue;
  		}
  		if (c == '
  ') {

  			*buf++ = '\\';
  			if (buf < end)
  				*buf++ = 'n';

  			continue;
  		}
  		buf++;

  	}
  	m->count = buf - m->buf;

  	seq_putc(m, '
  ');

  }
  
  /*
   * The task state array is a strange "bitmap" of
   * reasons to sleep. Thus "running" is zero, and
   * you can test for combinations of others with
   * simple bit tests.
   */

  static const char * const task_state_array[] = {

  	"R (running)",		/*   0 */
  	"S (sleeping)",		/*   1 */
  	"D (disk sleep)",	/*   2 */
  	"T (stopped)",		/*   4 */
  	"t (tracing stop)",	/*   8 */
  	"Z (zombie)",		/*  16 */
  	"X (dead)",		/*  32 */
  	"x (dead)",		/*  64 */

  	"K (wakekill)",		/* 128 */
  	"W (waking)",		/* 256 */

  };

  static inline const char *get_task_state(struct task_struct *tsk)

  {

  	unsigned int state = (tsk->state & TASK_REPORT) | tsk->exit_state;

  	const char * const *p = &task_state_array[0];

  	BUILD_BUG_ON(1 + ilog2(TASK_STATE_MAX) != ARRAY_SIZE(task_state_array));

  	while (state) {
  		p++;
  		state >>= 1;
  	}
  	return *p;
  }

  static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
  				struct pid *pid, struct task_struct *p)

  {
  	struct group_info *group_info;
  	int g;

  	struct fdtable *fdt = NULL;

  	const struct cred *cred;

  	pid_t ppid, tpid;

  	rcu_read_lock();

  	ppid = pid_alive(p) ?
  		task_tgid_nr_ns(rcu_dereference(p->real_parent), ns) : 0;

  	tpid = 0;
  	if (pid_alive(p)) {

  		struct task_struct *tracer = ptrace_parent(p);

  		if (tracer)
  			tpid = task_pid_nr_ns(tracer, ns);
  	}

  	cred = get_task_cred(p);

  	seq_printf(m,

  		"State:\t%s
  "

  		"Tgid:\t%d
  "
  		"Pid:\t%d
  "
  		"PPid:\t%d
  "
  		"TracerPid:\t%d
  "
  		"Uid:\t%d\t%d\t%d\t%d
  "
  		"Gid:\t%d\t%d\t%d\t%d
  ",
  		get_task_state(p),

  		task_tgid_nr_ns(p, ns),

  		pid_nr_ns(pid, ns),

  		ppid, tpid,

  		cred->uid, cred->euid, cred->suid, cred->fsuid,
  		cred->gid, cred->egid, cred->sgid, cred->fsgid);

  	task_lock(p);

  	if (p->files)
  		fdt = files_fdtable(p->files);

  	seq_printf(m,

  		"FDSize:\t%d
  "
  		"Groups:\t",

  		fdt ? fdt->max_fds : 0);

  	rcu_read_unlock();

  	group_info = cred->group_info;

  	task_unlock(p);

  	for (g = 0; g < min(group_info->ngroups, NGROUPS_SMALL); g++)

  		seq_printf(m, "%d ", GROUP_AT(group_info, g));

  	put_cred(cred);

  	seq_putc(m, '
  ');

  }

  static void render_sigset_t(struct seq_file *m, const char *header,
  				sigset_t *set)

  {

  	int i;

  	seq_puts(m, header);

  
  	i = _NSIG;
  	do {
  		int x = 0;
  
  		i -= 4;
  		if (sigismember(set, i+1)) x |= 1;
  		if (sigismember(set, i+2)) x |= 2;
  		if (sigismember(set, i+3)) x |= 4;
  		if (sigismember(set, i+4)) x |= 8;

  		seq_printf(m, "%x", x);

  	} while (i >= 4);

  	seq_putc(m, '
  ');

  }
  
  static void collect_sigign_sigcatch(struct task_struct *p, sigset_t *ign,
  				    sigset_t *catch)
  {
  	struct k_sigaction *k;
  	int i;
  
  	k = p->sighand->action;
  	for (i = 1; i <= _NSIG; ++i, ++k) {
  		if (k->sa.sa_handler == SIG_IGN)
  			sigaddset(ign, i);
  		else if (k->sa.sa_handler != SIG_DFL)
  			sigaddset(catch, i);
  	}
  }

  static inline void task_sig(struct seq_file *m, struct task_struct *p)

  {

  	unsigned long flags;

  	sigset_t pending, shpending, blocked, ignored, caught;
  	int num_threads = 0;
  	unsigned long qsize = 0;
  	unsigned long qlim = 0;
  
  	sigemptyset(&pending);
  	sigemptyset(&shpending);
  	sigemptyset(&blocked);
  	sigemptyset(&ignored);
  	sigemptyset(&caught);

  	if (lock_task_sighand(p, &flags)) {

  		pending = p->pending.signal;
  		shpending = p->signal->shared_pending.signal;
  		blocked = p->blocked;
  		collect_sigign_sigcatch(p, &ignored, &caught);

  		num_threads = get_nr_threads(p);

  		rcu_read_lock();  /* FIXME: is this correct? */

  		qsize = atomic_read(&__task_cred(p)->user->sigpending);

  		rcu_read_unlock();

  		qlim = task_rlimit(p, RLIMIT_SIGPENDING);

  		unlock_task_sighand(p, &flags);

  	}

  	seq_printf(m, "Threads:\t%d
  ", num_threads);
  	seq_printf(m, "SigQ:\t%lu/%lu
  ", qsize, qlim);

  
  	/* render them all */

  	render_sigset_t(m, "SigPnd:\t", &pending);
  	render_sigset_t(m, "ShdPnd:\t", &shpending);
  	render_sigset_t(m, "SigBlk:\t", &blocked);
  	render_sigset_t(m, "SigIgn:\t", &ignored);
  	render_sigset_t(m, "SigCgt:\t", &caught);

  }

  static void render_cap_t(struct seq_file *m, const char *header,
  			kernel_cap_t *a)

  {
  	unsigned __capi;

  	seq_puts(m, header);

  	CAP_FOR_EACH_U32(__capi) {

  		seq_printf(m, "%08x",

  			   a->cap[(_KERNEL_CAPABILITY_U32S-1) - __capi]);

  	}

  	seq_putc(m, '
  ');

  }

  static inline void task_cap(struct seq_file *m, struct task_struct *p)

  {

  	const struct cred *cred;
  	kernel_cap_t cap_inheritable, cap_permitted, cap_effective, cap_bset;

  	rcu_read_lock();
  	cred = __task_cred(p);
  	cap_inheritable	= cred->cap_inheritable;
  	cap_permitted	= cred->cap_permitted;
  	cap_effective	= cred->cap_effective;
  	cap_bset	= cred->cap_bset;
  	rcu_read_unlock();
  
  	render_cap_t(m, "CapInh:\t", &cap_inheritable);
  	render_cap_t(m, "CapPrm:\t", &cap_permitted);
  	render_cap_t(m, "CapEff:\t", &cap_effective);
  	render_cap_t(m, "CapBnd:\t", &cap_bset);

  }

  static inline void task_context_switch_counts(struct seq_file *m,
  						struct task_struct *p)

  {

  	seq_printf(m,	"voluntary_ctxt_switches:\t%lu
  "
  			"nonvoluntary_ctxt_switches:\t%lu
  ",
  			p->nvcsw,
  			p->nivcsw);

  }

  static void task_cpus_allowed(struct seq_file *m, struct task_struct *task)
  {

  	seq_puts(m, "Cpus_allowed:\t");

  	seq_cpumask(m, &task->cpus_allowed);

  	seq_putc(m, '
  ');
  	seq_puts(m, "Cpus_allowed_list:\t");

  	seq_cpumask_list(m, &task->cpus_allowed);

  	seq_putc(m, '
  ');

  }

  int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
  			struct pid *pid, struct task_struct *task)

  {

  	struct mm_struct *mm = get_task_mm(task);

  	task_name(m, task);
  	task_state(m, ns, pid, task);

  	if (mm) {

  		task_mem(m, mm);

  		mmput(mm);
  	}

  	task_sig(m, task);
  	task_cap(m, task);

  	task_cpus_allowed(m, task);

  	cpuset_task_status_allowed(m, task);

  	task_context_switch_counts(m, task);
  	return 0;

  }

  static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
  			struct pid *pid, struct task_struct *task, int whole)

  {
  	unsigned long vsize, eip, esp, wchan = ~0UL;
  	long priority, nice;
  	int tty_pgrp = -1, tty_nr = 0;
  	sigset_t sigign, sigcatch;
  	char state;

  	pid_t ppid = 0, pgid = -1, sid = -1;

  	int num_threads = 0;

  	int permitted;

  	struct mm_struct *mm;
  	unsigned long long start_time;
  	unsigned long cmin_flt = 0, cmaj_flt = 0;
  	unsigned long  min_flt = 0,  maj_flt = 0;

  	cputime_t cutime, cstime, utime, stime;

  	cputime_t cgtime, gtime;

  	unsigned long rsslim = 0;

  	char tcomm[sizeof(task->comm)];

  	unsigned long flags;

  
  	state = *get_task_state(task);
  	vsize = eip = esp = 0;

  	permitted = ptrace_may_access(task, PTRACE_MODE_READ | PTRACE_MODE_NOAUDIT);

  	mm = get_task_mm(task);
  	if (mm) {
  		vsize = task_vsize(mm);

  		if (permitted) {
  			eip = KSTK_EIP(task);
  			esp = KSTK_ESP(task);
  		}

  	}
  
  	get_task_comm(tcomm, task);
  
  	sigemptyset(&sigign);
  	sigemptyset(&sigcatch);

  	cutime = cstime = utime = stime = 0;
  	cgtime = gtime = 0;

  	if (lock_task_sighand(task, &flags)) {
  		struct signal_struct *sig = task->signal;

  
  		if (sig->tty) {

  			struct pid *pgrp = tty_get_pgrp(sig->tty);
  			tty_pgrp = pid_nr_ns(pgrp, ns);
  			put_pid(pgrp);

  			tty_nr = new_encode_dev(tty_devnum(sig->tty));

  		}

  		num_threads = get_nr_threads(task);

  		collect_sigign_sigcatch(task, &sigign, &sigcatch);

  		cmin_flt = sig->cmin_flt;
  		cmaj_flt = sig->cmaj_flt;
  		cutime = sig->cutime;
  		cstime = sig->cstime;

  		cgtime = sig->cgtime;

  		rsslim = ACCESS_ONCE(sig->rlim[RLIMIT_RSS].rlim_cur);

  		/* add up live thread stats at the group level */
  		if (whole) {

  			struct task_struct *t = task;

  			do {
  				min_flt += t->min_flt;
  				maj_flt += t->maj_flt;

  				gtime += t->gtime;

  				t = next_thread(t);
  			} while (t != task);

  			min_flt += sig->min_flt;
  			maj_flt += sig->maj_flt;

  			thread_group_times(task, &utime, &stime);

  			gtime += sig->gtime;

  		}

  		sid = task_session_nr_ns(task, ns);

  		ppid = task_tgid_nr_ns(task->real_parent, ns);

  		pgid = task_pgrp_nr_ns(task, ns);

  
  		unlock_task_sighand(task, &flags);

  	}

  	if (permitted && (!whole || num_threads < 2))

  		wchan = get_wchan(task);
  	if (!whole) {
  		min_flt = task->min_flt;
  		maj_flt = task->maj_flt;

  		task_times(task, &utime, &stime);

  		gtime = task->gtime;

  	}
  
  	/* scale priority and nice values from timeslices to -20..20 */
  	/* to make it look like a "normal" Unix priority/nice value  */
  	priority = task_prio(task);
  	nice = task_nice(task);
  
  	/* Temporary variable needed for gcc-2.96 */
  	/* convert timespec -> nsec*/

  	start_time =
  		(unsigned long long)task->real_start_time.tv_sec * NSEC_PER_SEC
  				+ task->real_start_time.tv_nsec;

  	/* convert nsec -> ticks */
  	start_time = nsec_to_clock_t(start_time);

  	seq_printf(m, "%d (%s) %c %d %d %d %d %d %u %lu \

  %lu %lu %lu %lu %lu %ld %ld %ld %ld %d 0 %llu %lu %ld %lu %lu %lu %lu %lu \

  %lu %lu %lu %lu %lu %lu %lu %lu %d %d %u %u %llu %lu %ld %lu %lu %lu
  ",

  		pid_nr_ns(pid, ns),

  		tcomm,
  		state,
  		ppid,
  		pgid,
  		sid,
  		tty_nr,
  		tty_pgrp,
  		task->flags,
  		min_flt,
  		cmin_flt,
  		maj_flt,
  		cmaj_flt,

  		cputime_to_clock_t(utime),
  		cputime_to_clock_t(stime),

  		cputime_to_clock_t(cutime),
  		cputime_to_clock_t(cstime),
  		priority,
  		nice,
  		num_threads,

  		start_time,
  		vsize,

  		mm ? get_mm_rss(mm) : 0,

  		rsslim,

  		mm ? (permitted ? mm->start_code : 1) : 0,
  		mm ? (permitted ? mm->end_code : 1) : 0,

  		(permitted && mm) ? mm->start_stack : 0,

  		esp,
  		eip,
  		/* The signal information here is obsolete.
  		 * It must be decimal for Linux 2.0 compatibility.
  		 * Use /proc/#/status for real-time signals.
  		 */
  		task->pending.signal.sig[0] & 0x7fffffffUL,
  		task->blocked.sig[0] & 0x7fffffffUL,
  		sigign      .sig[0] & 0x7fffffffUL,
  		sigcatch    .sig[0] & 0x7fffffffUL,
  		wchan,
  		0UL,
  		0UL,
  		task->exit_signal,
  		task_cpu(task),
  		task->rt_priority,

  		task->policy,

  		(unsigned long long)delayacct_blkio_ticks(task),
  		cputime_to_clock_t(gtime),

  		cputime_to_clock_t(cgtime),
  		(mm && permitted) ? mm->start_data : 0,
  		(mm && permitted) ? mm->end_data : 0,
  		(mm && permitted) ? mm->start_brk : 0);

  	if (mm)

  		mmput(mm);

  	return 0;

  }

  int proc_tid_stat(struct seq_file *m, struct pid_namespace *ns,
  			struct pid *pid, struct task_struct *task)

  {

  	return do_task_stat(m, ns, pid, task, 0);

  }

  int proc_tgid_stat(struct seq_file *m, struct pid_namespace *ns,
  			struct pid *pid, struct task_struct *task)

  {

  	return do_task_stat(m, ns, pid, task, 1);

  }

  int proc_pid_statm(struct seq_file *m, struct pid_namespace *ns,
  			struct pid *pid, struct task_struct *task)

  {

  	unsigned long size = 0, resident = 0, shared = 0, text = 0, data = 0;

  	struct mm_struct *mm = get_task_mm(task);

  	if (mm) {
  		size = task_statm(mm, &shared, &text, &data, &resident);
  		mmput(mm);
  	}

  	seq_printf(m, "%lu %lu %lu %lu 0 %lu 0
  ",
  			size, resident, shared, text, data);

  	return 0;

  }