/*
 *  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/config.h>
#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/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 <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/io.h>
#include <asm/processor.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;

	ADDBUF(buf, "Name:\t");
	name = p->comm;
	i = sizeof(p->comm);
	do {
		unsigned char c = *name;
		name++;
		i--;
		*buf = c;
		if (!c)
			break;
		if (c == '\\') {
			buf[1] = c;
			buf += 2;
			continue;
		}
		if (c == '\n') {
			buf[0] = '\\';
			buf[1] = 'n';
			buf += 2;
			continue;
		}
		buf++;
	} while (i);
	*buf = '\n';
	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)",		/*  8 */
	"Z (zombie)",		/*  4 */
	"X (dead)"		/* 16 */
};

static inline const char * get_task_state(struct task_struct *tsk)
{
	unsigned int state = tsk->state & (TASK_RUNNING |
					   TASK_INTERRUPTIBLE |
					   TASK_UNINTERRUPTIBLE |
					   TASK_ZOMBIE |
					   TASK_STOPPED);
	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)
{
	int g;

	read_lock(&tasklist_lock);
	buffer += sprintf(buffer,
		"State:\t%s\n"
		"Tgid:\t%d\n"
		"Pid:\t%d\n"
		"PPid:\t%d\n"
		"TracerPid:\t%d\n"
		"Uid:\t%d\t%d\t%d\t%d\n"
		"Gid:\t%d\t%d\t%d\t%d\n",
		get_task_state(p), p->tgid,
		p->pid, p->pid ? p->real_parent->pid : 0, 0,
		p->uid, p->euid, p->suid, p->fsuid,
		p->gid, p->egid, p->sgid, p->fsgid);
	read_unlock(&tasklist_lock);	
	task_lock(p);
	buffer += sprintf(buffer,
		"FDSize:\t%d\n"
		"Groups:\t",
		p->files ? p->files->max_fds : 0);
	task_unlock(p);

	for (g = 0; g < p->ngroups; g++)
		buffer += sprintf(buffer, "%d ", p->groups[g]);

	buffer += sprintf(buffer, "\n");
	return buffer;
}

static inline char * task_mem(struct mm_struct *mm, char *buffer)
{
	struct vm_area_struct * vma;
	unsigned long data = 0, stack = 0;
	unsigned long exec = 0, lib = 0;

	down_read(&mm->mmap_sem);
	for (vma = mm->mmap; vma; vma = vma->vm_next) {
		unsigned long len = (vma->vm_end - vma->vm_start) >> 10;
		if (!vma->vm_file) {
			data += len;
			if (vma->vm_flags & VM_GROWSDOWN)
				stack += len;
			continue;
		}
		if (vma->vm_flags & VM_WRITE)
			continue;
		if (vma->vm_flags & VM_EXEC) {
			exec += len;
			if (vma->vm_flags & VM_EXECUTABLE)
				continue;
			lib += len;
		}
	}
	buffer += sprintf(buffer,
		"VmSize:\t%8lu kB\n"
		"VmLck:\t%8lu kB\n"
		"VmRSS:\t%8lu kB\n"
		"VmData:\t%8lu kB\n"
		"VmStk:\t%8lu kB\n"
		"VmExe:\t%8lu kB\n"
		"VmLib:\t%8lu kB\n",
		mm->total_vm << (PAGE_SHIFT-10),
		mm->locked_vm << (PAGE_SHIFT-10),
		mm->rss << (PAGE_SHIFT-10),
		data - stack, stack,
		exec - lib, lib);
	up_read(&mm->mmap_sem);
	return buffer;
}

static void collect_sigign_sigcatch(struct task_struct *p, sigset_t *ign,
				    sigset_t *catch)
{
	struct k_sigaction *k;
	int i;

	sigemptyset(ign);
	sigemptyset(catch);

	read_lock(&tasklist_lock);
	if (p->sig) {
		spin_lock_irq(&p->sig->siglock);
		k = p->sig->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);
		}
		spin_unlock_irq(&p->sig->siglock);
	}
	read_unlock(&tasklist_lock);
}

static inline char * task_sig(struct task_struct *p, char *buffer)
{
	sigset_t ign, catch;

	buffer += sprintf(buffer, "SigPnd:\t");
	buffer = render_sigset_t(&p->pending.signal, buffer);
	*buffer++ = '\n';
	buffer += sprintf(buffer, "SigBlk:\t");
	buffer = render_sigset_t(&p->blocked, buffer);
	*buffer++ = '\n';

	collect_sigign_sigcatch(p, &ign, &catch);
	buffer += sprintf(buffer, "SigIgn:\t");
	buffer = render_sigset_t(&ign, buffer);
	*buffer++ = '\n';
	buffer += sprintf(buffer, "SigCgt:\t"); /* Linux 2.0 uses "SigCgt" */
	buffer = render_sigset_t(&catch, buffer);
	*buffer++ = '\n';

	return buffer;
}

static inline char *task_cap(struct task_struct *p, char *buffer)
{
    return buffer + sprintf(buffer, "CapInh:\t%016x\n"
			    "CapPrm:\t%016x\n"
			    "CapEff:\t%016x\n",
			    cap_t(p->cap_inheritable),
			    cap_t(p->cap_permitted),
			    cap_t(p->cap_effective));
}


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);
#if defined(CONFIG_ARCH_S390)
	buffer = task_show_regs(task, buffer);
#endif
	return buffer - orig;
}

int proc_pid_stat(struct task_struct *task, char * buffer)
{
	unsigned long vsize, eip, esp, wchan;
	long priority, nice;
	int tty_pgrp = -1, tty_nr = 0;
	sigset_t sigign, sigcatch;
	char state;
	int res;
	pid_t ppid;
	struct mm_struct *mm;

	state = *get_task_state(task);
	vsize = eip = esp = 0;
	task_lock(task);
	mm = task->mm;
	if(mm)
		atomic_inc(&mm->mm_users);
	if (task->tty) {
		tty_pgrp = task->tty->pgrp;
		tty_nr = kdev_t_to_nr(task->tty->device);
	}
	task_unlock(task);
	if (mm) {
		struct vm_area_struct *vma;
		down_read(&mm->mmap_sem);
		vma = mm->mmap;
		while (vma) {
			vsize += vma->vm_end - vma->vm_start;
			vma = vma->vm_next;
		}
		eip = KSTK_EIP(task);
		esp = KSTK_ESP(task);
		up_read(&mm->mmap_sem);
	}

	wchan = get_wchan(task);

	collect_sigign_sigcatch(task, &sigign, &sigcatch);

	/* 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);

	read_lock(&tasklist_lock);
	ppid = task->pid ? task->real_parent->pid : 0;
	read_unlock(&tasklist_lock);
	res = sprintf(buffer,"%d (%s) %c %d %d %d %d %d %lu %lu \
%lu %lu %lu %lu %lu %ld %ld %ld %ld %ld %ld %lu %lu %ld %lu %lu %lu %lu %lu \
%lu %lu %lu %lu %lu %lu %lu %lu %d %d %lu %lu\n",
		task->pid,
		task->comm,
		state,
		ppid,
		task->pgrp,
		task->session,
		tty_nr,
		tty_pgrp,
		task->flags,
		task->min_flt,
		task->cmin_flt,
		task->maj_flt,
		task->cmaj_flt,
		jiffies_to_clock_t(task->utime),
		jiffies_to_clock_t(task->stime),
		jiffies_to_clock_t(task->cutime),
		jiffies_to_clock_t(task->cstime),
		priority,
		nice,
		0UL /* removed */,
		jiffies_to_clock_t(task->it_real_value),
		jiffies_to_clock_t(task->start_time),
		vsize,
		mm ? mm->rss : 0, /* you might want to shift this left 3 */
		task->rlim[RLIMIT_RSS].rlim_cur,
		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,
		task->nswap,
		task->cnswap,
		task->exit_signal,
		task_cpu(task),
		task->rt_priority,
		task->policy);
	if(mm)
		mmput(mm);
	return res;
}
		
int proc_pid_statm(task_t *task, char *buffer)
{
	int size, resident, shared, text, lib, data, dirty;
	struct mm_struct *mm = get_task_mm(task);
	struct vm_area_struct * vma;

	size = resident = shared = text = lib = data = dirty = 0;

	if (!mm)
		goto out;

	down_read(&mm->mmap_sem);
	resident = mm->rss;
	for (vma = mm->mmap; vma; vma = vma->vm_next) {
		int pages = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;

		size += pages;
		if (is_vm_hugetlb_page(vma)) {
			if (!(vma->vm_flags & VM_DONTCOPY))
				shared += pages;
			continue;
		}
		if (vma->vm_flags & VM_SHARED || !list_empty(&vma->shared))
			shared += pages;
		if (vma->vm_flags & VM_EXECUTABLE)
			text += pages;
		else
			data += pages;
	}
	up_read(&mm->mmap_sem);
	mmput(mm);
out:
	return sprintf(buffer,"%d %d %d %d %d %d %d\n",
		       size, resident, shared, text, lib, data, dirty);
}

/*
 * The way we support synthetic files > 4K
 * - without storing their contents in some buffer and
 * - without walking through the entire synthetic file until we reach the
 *   position of the requested data
 * is to cleverly encode the current position in the file's f_pos field.
 * There is no requirement that a read() call which returns `count' bytes
 * of data increases f_pos by exactly `count'.
 *
 * This idea is Linus' one. Bruno implemented it.
 */

/*
 * For the /proc/<pid>/maps file, we use fixed length records, each containing
 * a single line.
 *
 * f_pos = (number of the vma in the task->mm->mmap list) * PAGE_SIZE
 *         + (index into the line)
 */
/* for systems with sizeof(void*) == 4: */
#define MAPS_LINE_FORMAT4	  "%08lx-%08lx %s %08lx %02x:%02x %lu"
#define MAPS_LINE_MAX4	49 /* sum of 8  1  8  1 4 1 8 1 5 1 10 1 */

/* for systems with sizeof(void*) == 8: */
#define MAPS_LINE_FORMAT8	  "%016lx-%016lx %s %016lx %02x:%02x %lu"
#define MAPS_LINE_MAX8	73 /* sum of 16  1  16  1 4 1 16 1 5 1 10 1 */

#define MAPS_LINE_FORMAT	(sizeof(void*) == 4 ? MAPS_LINE_FORMAT4 : MAPS_LINE_FORMAT8)
#define MAPS_LINE_MAX	(sizeof(void*) == 4 ?  MAPS_LINE_MAX4 :  MAPS_LINE_MAX8)

static int proc_pid_maps_get_line (char *buf, struct vm_area_struct *map)
{
	/* produce the next line */
	char *line;
	char str[5];
	int flags;
	dev_t dev;
	unsigned long ino;
	int len;

	flags = map->vm_flags;

	str[0] = flags & VM_READ ? 'r' : '-';
	str[1] = flags & VM_WRITE ? 'w' : '-';
	str[2] = flags & VM_EXEC ? 'x' : '-';
	str[3] = flags & VM_MAYSHARE ? 's' : 'p';
	str[4] = 0;

	dev = 0;
	ino = 0;
	if (map->vm_file != NULL) {
		struct inode *inode = map->vm_file->f_dentry->d_inode;
		dev = inode->i_sb->s_dev;
		ino = inode->i_ino;
		line = d_path(map->vm_file->f_dentry,
			      map->vm_file->f_vfsmnt,
			      buf, PAGE_SIZE);
		buf[PAGE_SIZE-1] = '\n';
		line -= MAPS_LINE_MAX;
		if(line < buf)
			line = buf;
	} else
		line = buf;

	len = sprintf(line,
		      MAPS_LINE_FORMAT,
		      map->vm_start, map->vm_end, str, map->vm_pgoff << PAGE_SHIFT,
		      MAJOR(dev), MINOR(dev), ino);

	if(map->vm_file) {
		int i;
		for(i = len; i < MAPS_LINE_MAX; i++)
			line[i] = ' ';
		len = buf + PAGE_SIZE - line;
		memmove(buf, line, len);
	} else
		line[len++] = '\n';
	return len;
}

#ifdef CONFIG_MMU
ssize_t proc_pid_read_maps(struct task_struct *task, struct file *file,
			   char *buf, size_t count, loff_t *ppos)
{
	struct mm_struct *mm;
	struct vm_area_struct * map;
	char *tmp, *kbuf;
	long retval;
	int off, lineno, loff;

	/* reject calls with out of range parameters immediately */
	retval = 0;
	if (*ppos > LONG_MAX)
		goto out;
	if (count == 0)
		goto out;
	off = (long)*ppos;
	/*
	 * We might sleep getting the page, so get it first.
	 */
	retval = -ENOMEM;
	kbuf = (char*)__get_free_page(GFP_KERNEL);
	if (!kbuf)
		goto out;

	tmp = (char*)__get_free_page(GFP_KERNEL);
	if (!tmp)
		goto out_free1;

	mm = get_task_mm(task);
 
	retval = 0;
	if (!mm)
		goto out_free2;

	down_read(&mm->mmap_sem);
	map = mm->mmap;
	lineno = 0;
	loff = 0;
	if (count > PAGE_SIZE)
		count = PAGE_SIZE;
	while (map) {
		int len;
		if (off > PAGE_SIZE) {
			off -= PAGE_SIZE;
			goto next;
		}
		len = proc_pid_maps_get_line(tmp, map);
		len -= off;
		if (len > 0) {
			if (retval+len > count) {
				/* only partial line transfer possible */
				len = count - retval;
				/* save the offset where the next read
				 * must start */
				loff = len+off;
			}
			memcpy(kbuf+retval, tmp+off, len);
			retval += len;
		}
		off = 0;
next:
		if (!loff)
			lineno++;
		if (retval >= count)
			break;
		if (loff) BUG();
		map = map->vm_next;
	}
	up_read(&mm->mmap_sem);
	mmput(mm);

	if (retval > count) BUG();
	if (copy_to_user(buf, kbuf, retval))
		retval = -EFAULT;
	else
		*ppos = (lineno << PAGE_SHIFT) + loff;

out_free2:
	free_page((unsigned long)tmp);
out_free1:
	free_page((unsigned long)kbuf);
out:
	return retval;
}
#endif /* CONFIG_MMU */