array.c

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/*
 *  linux/fs/proc/array.c
 *
 *  Copyright (C) 1992  by Linus Torvalds
 *  based on ideas by Darren Senn
 *
 * Fixes:
 * Michael. K. Johnson: stat,statm extensions.
 *                      <[e-mail]>
 *
 * 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.
 *                      <[e-mail]>
 *
 * Danny ter Haar    :	added cpuinfo 
 *			<[e-mail]>
 *
 * Alessandro Rubini :  profile extension.
 *                      <[e-mail]>
 *
 * Jeff Tranter      :  added BogoMips field to cpuinfo
 *                      <[e-mail]>
 *
 * Bruno Haible      :  remove 4K limit for the maps file
 * <[e-mail]>
 *
 * Yves Arrouye      :  remove removal of trailing spaces in get_array.
 *			<[e-mail]>
 */

#include <linux/types.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/kernel_stat.h>
#include <linux/tty.h>
#include <linux/user.h>
#include <linux/a.out.h>
#include <linux/string.h>
#include <linux/mman.h>
#include <linux/proc_fs.h>
#include <linux/ioport.h>
#include <linux/config.h>
#include <linux/mm.h>
#include <linux/pagemap.h>
#include <linux/swap.h>

#include <asm/segment.h>
#include <asm/pgtable.h>
#include <asm/io.h>

#define LOAD_INT(x) ((x) >> FSHIFT)
#define LOAD_FRAC(x) LOAD_INT(((x) & (FIXED_1-1)) * 100)

#ifdef CONFIG_DEBUG_MALLOC
int get_malloc(char * buffer);
#endif


static int read_core(struct inode * inode, struct file * file,char * buf, int count)
{
	unsigned long p = file->f_pos, memsize;
	int read;
	int count1;
	char * pnt;
	struct user dump;
#ifdef __i386__
#	define FIRST_MAPPED	PAGE_SIZE	/* we don't have page 0 mapped on x86.. */
#else
#	define FIRST_MAPPED	0
#endif

	memset(&dump, 0, sizeof(struct user));
	dump.magic = CMAGIC;
	dump.u_dsize = MAP_NR(high_memory);
#ifdef __alpha__
	dump.start_data = PAGE_OFFSET;
#endif

	if (count < 0)
		return -EINVAL;
	memsize = MAP_NR(high_memory + PAGE_SIZE) << PAGE_SHIFT;
	if (p >= memsize)
		return 0;
	if (count > memsize - p)
		count = memsize - p;
	read = 0;

	if (p < sizeof(struct user) && count > 0) {
		count1 = count;
		if (p + count1 > sizeof(struct user))
			count1 = sizeof(struct user)-p;
		pnt = (char *) &dump + p;
		memcpy_tofs(buf,(void *) pnt, count1);
		buf += count1;
		p += count1;
		count -= count1;
		read += count1;
	}

	while (count > 0 && p < PAGE_SIZE + FIRST_MAPPED) {
		put_user(0,buf);
		buf++;
		p++;
		count--;
		read++;
	}
	memcpy_tofs(buf, (void *) (PAGE_OFFSET + p - PAGE_SIZE), count);
	read += count;
	file->f_pos += read;
	return read;
}

static struct file_operations proc_kcore_operations = {
	NULL,           /* lseek */
	read_core,
};

struct inode_operations proc_kcore_inode_operations = {
	&proc_kcore_operations, 
};


/*
 * This function accesses profiling information. The returned data is
 * binary: the sampling step and the actual contents of the profile
 * buffer. Use of the program readprofile is recommended in order to
 * get meaningful info out of these data.
 */
static int read_profile(struct inode *inode, struct file *file, char *buf, int count)
{
	unsigned long p = file->f_pos;
	int read;
	char * pnt;
	unsigned int sample_step = 1 << prof_shift;

	if (count < 0)
		return -EINVAL;
	if (p >= (prof_len+1)*sizeof(unsigned int))
		return 0;
	if (count > (prof_len+1)*sizeof(unsigned int) - p)
		count = (prof_len+1)*sizeof(unsigned int) - p;
	read = 0;

	while (p < sizeof(unsigned int) && count > 0) {
		put_user(*((char *)(&sample_step)+p),buf);
		buf++; p++; count--; read++;
	}
	pnt = (char *)prof_buffer + p - sizeof(unsigned int);
	memcpy_tofs(buf,(void *)pnt,count);
	read += count;
	file->f_pos += read;
	return read;
}

/* Writing to /proc/profile resets the counters */
static int write_profile(struct inode * inode, struct file * file, const char * buf, int count)
{
    int i=prof_len;

    while (i--)
	    prof_buffer[i]=0UL;
    return count;
}

static struct file_operations proc_profile_operations = {
	NULL,           /* lseek */
	read_profile,
	write_profile,
};

struct inode_operations proc_profile_inode_operations = {
	&proc_profile_operations, 
};


static int get_loadavg(char * buffer)
{
	int a, b, c;

	a = avenrun[0] + (FIXED_1/200);
	b = avenrun[1] + (FIXED_1/200);
	c = avenrun[2] + (FIXED_1/200);
	return sprintf(buffer,"%d.%02d %d.%02d %d.%02d %d/%d %d\n",
		LOAD_INT(a), LOAD_FRAC(a),
		LOAD_INT(b), LOAD_FRAC(b),
		LOAD_INT(c), LOAD_FRAC(c),
		nr_running, nr_tasks, last_pid);
}

static int get_kstat(char * buffer)
{
	int i, len;
	unsigned sum = 0;
	extern unsigned long total_forks;

	for (i = 0 ; i < NR_IRQS ; i++)
		sum += kstat.interrupts[i];
	len = sprintf(buffer,
		"cpu  %u %u %u %lu\n"
		"disk %u %u %u %u\n"
		"disk_rio %u %u %u %u\n"
		"disk_wio %u %u %u %u\n"
		"disk_rblk %u %u %u %u\n"
		"disk_wblk %u %u %u %u\n"
		"page %u %u\n"
		"swap %u %u\n"
		"intr %u",
		kstat.cpu_user,
		kstat.cpu_nice,
		kstat.cpu_system,
		jiffies - (kstat.cpu_user + kstat.cpu_nice + kstat.cpu_system),
		kstat.dk_drive[0], kstat.dk_drive[1],
		kstat.dk_drive[2], kstat.dk_drive[3],
		kstat.dk_drive_rio[0], kstat.dk_drive_rio[1],
		kstat.dk_drive_rio[2], kstat.dk_drive_rio[3],
		kstat.dk_drive_wio[0], kstat.dk_drive_wio[1],
		kstat.dk_drive_wio[2], kstat.dk_drive_wio[3],
		kstat.dk_drive_rblk[0], kstat.dk_drive_rblk[1],
		kstat.dk_drive_rblk[2], kstat.dk_drive_rblk[3],
		kstat.dk_drive_wblk[0], kstat.dk_drive_wblk[1],
		kstat.dk_drive_wblk[2], kstat.dk_drive_wblk[3],
		kstat.pgpgin,
		kstat.pgpgout,
		kstat.pswpin,
		kstat.pswpout,
		sum);
	for (i = 0 ; i < NR_IRQS ; i++)
		len += sprintf(buffer + len, " %u", kstat.interrupts[i]);
	len += sprintf(buffer + len,
		"\nctxt %u\n"
		"btime %lu\n"
		"processes %lu\n",
		kstat.context_swtch,
		xtime.tv_sec - jiffies / HZ,
		total_forks);
	return len;
}


static int get_uptime(char * buffer)
{
	unsigned long uptime;
	unsigned long idle;

	uptime = jiffies;
	idle = task[0]->utime + task[0]->stime;

	/* The formula for the fraction parts really is ((t * 100) / HZ) % 100, but
	   that would overflow about every five days at HZ == 100.
	   Therefore the identity a = (a / b) * b + a % b is used so that it is
	   calculated as (((t / HZ) * 100) + ((t % HZ) * 100) / HZ) % 100.
	   The part in front of the '+' always evaluates as 0 (mod 100). All divisions
	   in the above formulas are truncating. For HZ being a power of 10, the
	   calculations simplify to the version in the #else part (if the printf
	   format is adapted to the same number of digits as zeroes in HZ.
	 */
#if HZ!=100
	return sprintf(buffer,"%lu.%02lu %lu.%02lu\n",
		uptime / HZ,
		(((uptime % HZ) * 100) / HZ) % 100,
		idle / HZ,
		(((idle % HZ) * 100) / HZ) % 100);
#else
	return sprintf(buffer,"%lu.%02lu %lu.%02lu\n",
		uptime / HZ,
		uptime % HZ,
		idle / HZ,
		idle % HZ);
#endif
}

static int get_meminfo(char * buffer)
{
	struct sysinfo i;
	int len;
	
	len = show_free_areas_proc(buffer);

	si_meminfo(&i);
	si_swapinfo(&i);
	len += sprintf(buffer + len,
		       "        total:    used:    free:  shared: buffers:  cached:\n"
		"Mem:  %8lu %8lu %8lu %8lu %8lu %8lu\n"
		"Swap: %8lu %8lu %8lu\n",
		i.totalram, i.totalram-i.freeram, i.freeram, i.sharedram, i.bufferram, page_cache_size*PAGE_SIZE,
		i.totalswap, i.totalswap-i.freeswap, i.freeswap);
	/*
	 * Tagged format, for easy grepping and expansion. The above will go away
	 * eventually, once the tools have been updated.
	 */
	return len + sprintf(buffer+len,
		"MemTotal:  %8lu kB\n"
		"MemFree:   %8lu kB\n"
		"MemShared: %8lu kB\n"
		"Buffers:   %8lu kB\n"
		"Cached:    %8lu kB\n"
		"SwapTotal: %8lu kB\n"
		"SwapFree:  %8lu kB\n",
		i.totalram >> 10,
		i.freeram >> 10,
		i.sharedram >> 10,
		i.bufferram >> 10,
		page_cache_size << (PAGE_SHIFT - 10),
		i.totalswap >> 10,
		i.freeswap >> 10);
}

static int get_version(char * buffer)
{
	extern const char *linux_banner;

	strcpy(buffer, linux_banner);
	return strlen(buffer);
}

static int get_cmdline(char * buffer)
{
	extern char saved_command_line[];

	return sprintf(buffer, "%s\n", saved_command_line);
}

static struct task_struct ** get_task(pid_t pid)
{
	struct task_struct ** p;

	p = task;
	while (++p < task+NR_TASKS) {
		if (*p && (*p)->pid == pid)
			return p;
	}
	return NULL;
}

static unsigned long get_phys_addr(struct task_struct * p, unsigned long ptr)
{
#ifdef NO_MM
	return ptr;
#else
	pgd_t *page_dir;
	pmd_t *page_middle;
	pte_t pte;

	if (!p || !p->mm || ptr >= TASK_SIZE)
		return 0;
	page_dir = pgd_offset(p->mm,ptr);
	if (pgd_none(*page_dir))
		return 0;
	if (pgd_bad(*page_dir)) {
		printk("bad page directory entry %08lx\n", pgd_val(*page_dir));
		pgd_clear(page_dir);
		return 0;
	}
	page_middle = pmd_offset(page_dir,ptr);
	if (pmd_none(*page_middle))
		return 0;
	if (pmd_bad(*page_middle)) {
		printk("bad page middle entry %08lx\n", pmd_val(*page_middle));
		pmd_clear(page_middle);
		return 0;
	}
	pte = *pte_offset(page_middle,ptr);
	if (!pte_present(pte))
		return 0;
	return pte_page(pte) + (ptr & ~PAGE_MASK);
#endif
}

static int get_array(struct task_struct ** p, unsigned long start, unsigned long end, char * buffer)
{
	unsigned long addr;
	int size = 0, result = 0;
	char c;

	if (start >= end)
		return result;
	for (;;) {
		addr = get_phys_addr(*p, start);
		if (!addr)
			return result;
		do {
			c = *(char *) addr;
			if (!c)
				result = size;
			if (size < PAGE_SIZE)
				buffer[size++] = c;
			else
				return result;
			addr++;
			start++;
			if (!c && start >= end)
				return result;
		} while (addr & ~PAGE_MASK);
	}
	return result;
}

static int get_env(int pid, char * buffer)
{
	struct task_struct ** p = get_task(pid);

	if (!p || !*p || !(*p)->mm)
		return 0;
	return get_array(p, (*p)->mm->env_start, (*p)->mm->env_end, buffer);
}

static int get_arg(int pid, char * buffer)
{
	struct task_struct ** p = get_task(pid);

	if (!p || !*p || !(*p)->mm)
		return 0;
	return get_array(p, (*p)->mm->arg_start, (*p)->mm->arg_end, buffer);
}

static unsigned long get_wchan(struct task_struct *p)
{
	if (!p || p == current || p->state == TASK_RUNNING)
		return 0;
#if defined(__i386__)
	{
		unsigned long ebp, eip;
		unsigned long stack_page;
		int count = 0;