/*
   *  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.Cox@linux.org>
   *
   * 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/slab.h>
  #include <linux/smp.h>
  #include <linux/signal.h>
  #include <linux/highmem.h>
  #include <linux/file.h>
  #include <linux/times.h>
  #include <linux/cpuset.h>

  #include <linux/rcupdate.h>

  #include <linux/delayacct.h>

  #include <asm/pgtable.h>

  #include <asm/processor.h>
  #include "internal.h"
  
  /* Gcc optimizes away "strlen(x)" for constant x */
  #define ADDBUF(buffer, string) \
  do { memcpy(buffer, string, strlen(string)); \
       buffer += strlen(string); } while (0)

  static inline char *task_name(struct task_struct *p, char *buf)

  {
  	int i;

  	char *name;

  	char tcomm[sizeof(p->comm)];
  
  	get_task_comm(tcomm, p);
  
  	ADDBUF(buf, "Name:\t");
  	name = tcomm;
  	i = sizeof(tcomm);
  	do {
  		unsigned char c = *name;
  		name++;
  		i--;
  		*buf = c;
  		if (!c)
  			break;
  		if (c == '\\') {
  			buf[1] = c;
  			buf += 2;
  			continue;
  		}
  		if (c == '
  ') {
  			buf[0] = '\\';
  			buf[1] = 'n';
  			buf += 2;
  			continue;
  		}
  		buf++;
  	} while (i);
  	*buf = '
  ';
  	return buf+1;
  }
  
  /*
   * 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 *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 */
  };

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

  {
  	unsigned int state = (tsk->state & (TASK_RUNNING |
  					    TASK_INTERRUPTIBLE |
  					    TASK_UNINTERRUPTIBLE |
  					    TASK_STOPPED |
  					    TASK_TRACED)) |
  			(tsk->exit_state & (EXIT_ZOMBIE |
  					    EXIT_DEAD));
  	const char **p = &task_state_array[0];
  
  	while (state) {
  		p++;
  		state >>= 1;
  	}
  	return *p;
  }

  static inline char *task_state(struct task_struct *p, char *buffer)

  {
  	struct group_info *group_info;
  	int g;

  	struct fdtable *fdt = NULL;

  	rcu_read_lock();

  	buffer += sprintf(buffer,
  		"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),

  		p->tgid, p->pid,
  		pid_alive(p) ? rcu_dereference(p->real_parent)->tgid : 0,

  		pid_alive(p) && p->ptrace ? rcu_dereference(p->parent)->pid : 0,

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

  	task_lock(p);

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

  	buffer += sprintf(buffer,
  		"FDSize:\t%d
  "
  		"Groups:\t",

  		fdt ? fdt->max_fds : 0);

  	rcu_read_unlock();

  
  	group_info = p->group_info;
  	get_group_info(group_info);
  	task_unlock(p);

  	for (g = 0; g < min(group_info->ngroups, NGROUPS_SMALL); g++)
  		buffer += sprintf(buffer, "%d ", GROUP_AT(group_info, g));

  	put_group_info(group_info);
  
  	buffer += sprintf(buffer, "
  ");
  	return buffer;
  }

  static char *render_sigset_t(const char *header, sigset_t *set, char *buffer)

  {
  	int i, len;
  
  	len = strlen(header);
  	memcpy(buffer, header, len);
  	buffer += len;
  
  	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;
  		*buffer++ = (x < 10 ? '0' : 'a' - 10) + x;
  	} while (i >= 4);
  
  	*buffer++ = '
  ';
  	*buffer = 0;
  	return buffer;
  }
  
  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 char *task_sig(struct task_struct *p, char *buffer)

  {

  	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);

  	rcu_read_lock();
  	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 = atomic_read(&p->signal->count);
  		qsize = atomic_read(&p->user->sigpending);
  		qlim = p->signal->rlim[RLIMIT_SIGPENDING].rlim_cur;

  		unlock_task_sighand(p, &flags);

  	}

  	rcu_read_unlock();

  
  	buffer += sprintf(buffer, "Threads:\t%d
  ", num_threads);
  	buffer += sprintf(buffer, "SigQ:\t%lu/%lu
  ", qsize, qlim);
  
  	/* render them all */
  	buffer = render_sigset_t("SigPnd:\t", &pending, buffer);
  	buffer = render_sigset_t("ShdPnd:\t", &shpending, buffer);
  	buffer = render_sigset_t("SigBlk:\t", &blocked, buffer);
  	buffer = render_sigset_t("SigIgn:\t", &ignored, buffer);
  	buffer = render_sigset_t("SigCgt:\t", &caught, buffer);
  
  	return buffer;
  }
  
  static inline char *task_cap(struct task_struct *p, char *buffer)
  {
      return buffer + sprintf(buffer, "CapInh:\t%016x
  "
  			    "CapPrm:\t%016x
  "
  			    "CapEff:\t%016x
  ",
  			    cap_t(p->cap_inheritable),
  			    cap_t(p->cap_permitted),
  			    cap_t(p->cap_effective));
  }

  static inline char *task_context_switch_counts(struct task_struct *p,
  						char *buffer)
  {
  	return buffer + sprintf(buffer, "voluntary_ctxt_switches:\t%lu
  "
  			    "nonvoluntary_ctxt_switches:\t%lu
  ",
  			    p->nvcsw,
  			    p->nivcsw);
  }

  int proc_pid_status(struct task_struct *task, char *buffer)

  {

  	char *orig = buffer;

  	struct mm_struct *mm = get_task_mm(task);
  
  	buffer = task_name(task, buffer);
  	buffer = task_state(task, buffer);

  	if (mm) {
  		buffer = task_mem(mm, buffer);
  		mmput(mm);
  	}
  	buffer = task_sig(task, buffer);
  	buffer = task_cap(task, buffer);
  	buffer = cpuset_task_status_allowed(task, buffer);

  #if defined(CONFIG_S390)

  	buffer = task_show_regs(task, buffer);
  #endif

  	buffer = task_context_switch_counts(task, buffer);

  	return buffer - orig;
  }

  static clock_t task_utime(struct task_struct *p)
  {
  	clock_t utime = cputime_to_clock_t(p->utime),
  		total = utime + cputime_to_clock_t(p->stime);
  	u64 temp;
  
  	/*
  	 * Use CFS's precise accounting:
  	 */
  	temp = (u64)nsec_to_clock_t(p->se.sum_exec_runtime);
  
  	if (total) {
  		temp *= utime;
  		do_div(temp, total);
  	}
  	utime = (clock_t)temp;
  
  	return utime;
  }
  
  static clock_t task_stime(struct task_struct *p)
  {

  	clock_t stime;

  
  	/*
  	 * Use CFS's precise accounting. (we subtract utime from
  	 * the total, to make sure the total observed by userspace
  	 * grows monotonically - apps rely on that):
  	 */
  	stime = nsec_to_clock_t(p->se.sum_exec_runtime) - task_utime(p);
  
  	return stime;
  }

  static int do_task_stat(struct task_struct *task, char *buffer, 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;
  	int res;

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

  	int num_threads = 0;
  	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;
  	clock_t utime, stime;

  	unsigned long rsslim = 0;

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

  	unsigned long flags;

  
  	state = *get_task_state(task);
  	vsize = eip = esp = 0;
  	mm = get_task_mm(task);
  	if (mm) {
  		vsize = task_vsize(mm);
  		eip = KSTK_EIP(task);
  		esp = KSTK_ESP(task);
  	}
  
  	get_task_comm(tcomm, task);
  
  	sigemptyset(&sigign);
  	sigemptyset(&sigcatch);

  	cutime = cstime = cputime_zero;
  	utime = stime = 0;

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

  
  		if (sig->tty) {

  			tty_pgrp = pid_nr(sig->tty->pgrp);

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

  		}
  
  		num_threads = atomic_read(&sig->count);

  		collect_sigign_sigcatch(task, &sigign, &sigcatch);

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

  				utime += task_utime(t);
  				stime += task_stime(t);

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

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

  			utime += cputime_to_clock_t(sig->utime);
  			stime += cputime_to_clock_t(sig->stime);

  		}

  		sid = signal_session(sig);

  		pgid = process_group(task);

  		ppid = rcu_dereference(task->real_parent)->tgid;
  
  		unlock_task_sighand(task, &flags);

  	}

  	rcu_read_unlock();

  	if (!whole || num_threads < 2)

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

  		utime = task_utime(task);
  		stime = task_stime(task);

  	}
  
  	/* 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);

  	res = sprintf(buffer, "%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
  ",

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

  		utime,
  		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 ? mm->start_code : 0,
  		mm ? mm->end_code : 0,
  		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));

  	if (mm)

  		mmput(mm);
  	return res;
  }

  int proc_tid_stat(struct task_struct *task, char *buffer)

  {
  	return do_task_stat(task, buffer, 0);
  }

  int proc_tgid_stat(struct task_struct *task, char *buffer)

  {
  	return do_task_stat(task, buffer, 1);
  }
  
  int proc_pid_statm(struct task_struct *task, char *buffer)
  {
  	int size = 0, resident = 0, shared = 0, text = 0, lib = 0, data = 0;
  	struct mm_struct *mm = get_task_mm(task);

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

  	return sprintf(buffer, "%d %d %d %d %d %d %d
  ",

  		       size, resident, shared, text, lib, data, 0);
  }