proc_misc.c

嵌入式系统设计与实验教材二源码linux内核移植与编译

/*
 *  linux/fs/proc/proc_misc.c
 *
 *  linux/fs/proc/array.c
 *  Copyright (C) 1992  by Linus Torvalds
 *  based on ideas by Darren Senn
 *
 *  This used to be the part of array.c. See the rest of history and credits
 *  there. I took this into a separate file and switched the thing to generic
 *  proc_file_inode_operations, leaving in array.c only per-process stuff.
 *  Inumbers allocation made dynamic (via create_proc_entry()).  AV, May 1999.
 *
 * Changes:
 * Fulton Green      :  Encapsulated position metric calculations.
 *			<[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/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 <linux/slab.h>
#include <linux/smp.h>
#include <linux/signal.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/smp_lock.h>
#include <linux/seq_file.h>

#include <asm/uaccess.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)
/*
 * Warning: stuff below (imported functions) assumes that its output will fit
 * into one page. For some of those functions it may be wrong. Moreover, we
 * have a way to deal with that gracefully. Right now I used straightforward
 * wrappers, but this needs further analysis wrt potential overflows.
 */
#ifdef CONFIG_MODULES
extern int get_module_list(char *);
#endif
extern int get_device_list(char *);
extern int get_partition_list(char *, char **, off_t, int);
extern int get_filesystem_list(char *);
extern int get_exec_domain_list(char *);
extern int get_irq_list(char *);
extern int get_dma_list(char *);
extern int get_locks_status (char *, char **, off_t, int);
extern int get_swaparea_info (char *);
#ifdef CONFIG_SGI_DS1286
extern int get_ds1286_status(char *);
#endif

static int proc_calc_metrics(char *page, char **start, off_t off,
				 int count, int *eof, int len)
{
	if (len <= off+count) *eof = 1;
	*start = page + off;
	len -= off;
	if (len>count) len = count;
	if (len<0) len = 0;
	return len;
}

static int loadavg_read_proc(char *page, char **start, off_t off,
				 int count, int *eof, void *data)
{
	int a, b, c;
	int len;

	a = avenrun[0] + (FIXED_1/200);
	b = avenrun[1] + (FIXED_1/200);
	c = avenrun[2] + (FIXED_1/200);
	len = sprintf(page,"%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_threads, last_pid);
	return proc_calc_metrics(page, start, off, count, eof, len);
}

static int uptime_read_proc(char *page, char **start, off_t off,
				 int count, int *eof, void *data)
{
	unsigned long uptime;
	unsigned long idle;
	int len;

	uptime = jiffies;
	idle = init_tasks[0]->times.tms_utime + init_tasks[0]->times.tms_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
	len = sprintf(page,"%lu.%02lu %lu.%02lu\n",
		uptime / HZ,
		(((uptime % HZ) * 100) / HZ) % 100,
		idle / HZ,
		(((idle % HZ) * 100) / HZ) % 100);
#else
	len = sprintf(page,"%lu.%02lu %lu.%02lu\n",
		uptime / HZ,
		uptime % HZ,
		idle / HZ,
		idle % HZ);
#endif
	return proc_calc_metrics(page, start, off, count, eof, len);
}

static int meminfo_read_proc(char *page, char **start, off_t off,
				 int count, int *eof, void *data)
{
	struct sysinfo i;
	int len;
	int pg_size ;

/*
 * display in kilobytes.
 */
#define K(x) ((x) << (PAGE_SHIFT - 10))
#define B(x) ((unsigned long long)(x) << PAGE_SHIFT)
	si_meminfo(&i);
	si_swapinfo(&i);
	pg_size = atomic_read(&page_cache_size) - i.bufferram ;

	len = sprintf(page, "        total:    used:    free:  shared: buffers:  cached:\n"
		"Mem:  %8Lu %8Lu %8Lu %8Lu %8Lu %8Lu\n"
		"Swap: %8Lu %8Lu %8Lu\n",
		B(i.totalram), B(i.totalram-i.freeram), B(i.freeram),
		B(i.sharedram), B(i.bufferram),
		B(pg_size), B(i.totalswap),
		B(i.totalswap-i.freeswap), B(i.freeswap));
	/*
	 * Tagged format, for easy grepping and expansion.
	 * The above will go away eventually, once the tools
	 * have been updated.
	 */
	len += sprintf(page+len,
		"MemTotal:     %8lu kB\n"
		"MemFree:      %8lu kB\n"
		"MemShared:    %8lu kB\n"
		"Buffers:      %8lu kB\n"
		"Cached:       %8lu kB\n"
		"SwapCached:   %8lu kB\n"
		"Active:       %8u kB\n"
		"Inactive:     %8u kB\n"
		"HighTotal:    %8lu kB\n"
		"HighFree:     %8lu kB\n"
		"LowTotal:     %8lu kB\n"
		"LowFree:      %8lu kB\n"
		"SwapTotal:    %8lu kB\n"
		"SwapFree:     %8lu kB\n",
		K(i.totalram),
		K(i.freeram),
		K(i.sharedram),
		K(i.bufferram),
		K(pg_size - swapper_space.nrpages),
		K(swapper_space.nrpages),
		K(nr_active_pages),
		K(nr_inactive_pages),
		K(i.totalhigh),
		K(i.freehigh),
		K(i.totalram-i.totalhigh),
		K(i.freeram-i.freehigh),
		K(i.totalswap),
		K(i.freeswap));

	return proc_calc_metrics(page, start, off, count, eof, len);
#undef B
#undef K
}

static int version_read_proc(char *page, char **start, off_t off,
				 int count, int *eof, void *data)
{
	extern char *linux_banner;
	int len;

	strcpy(page, linux_banner);
	len = strlen(page);
	return proc_calc_metrics(page, start, off, count, eof, len);
}

extern struct seq_operations cpuinfo_op;
static int cpuinfo_open(struct inode *inode, struct file *file)
{
	return seq_open(file, &cpuinfo_op);
}
static struct file_operations proc_cpuinfo_operations = {
	open:		cpuinfo_open,
	read:		seq_read,
	llseek:		seq_lseek,
	release:	seq_release,
};

#ifdef CONFIG_MODULES
static int modules_read_proc(char *page, char **start, off_t off,
				 int count, int *eof, void *data)
{
	int len = get_module_list(page);
	return proc_calc_metrics(page, start, off, count, eof, len);
}

extern struct seq_operations ksyms_op;
static int ksyms_open(struct inode *inode, struct file *file)
{
	return seq_open(file, &ksyms_op);
}
static struct file_operations proc_ksyms_operations = {
	open:		ksyms_open,
	read:		seq_read,
	llseek:		seq_lseek,
	release:	seq_release,
};
#endif

static int kstat_read_proc(char *page, char **start, off_t off,
				 int count, int *eof, void *data)
{
	int i, len;
	extern unsigned long total_forks;
	unsigned long jif = hz_to_std(jiffies);
	unsigned int sum = 0, user = 0, nice = 0, system = 0;
	int major, disk;

	for (i = 0 ; i < smp_num_cpus; i++) {
		int cpu = cpu_logical_map(i), j;

		user += hz_to_std(kstat.per_cpu_user[cpu]);
		nice += hz_to_std(kstat.per_cpu_nice[cpu]);
		system += hz_to_std(kstat.per_cpu_system[cpu]);
#if !defined(CONFIG_ARCH_S390)
		for (j = 0 ; j < NR_IRQS ; j++)
			sum += kstat.irqs[cpu][j];
#endif
	}

	len = sprintf(page, "cpu  %u %u %u %lu\n", user, nice, system,
		      jif * smp_num_cpus - (user + nice + system));
	for (i = 0 ; i < smp_num_cpus; i++)
		len += sprintf(page + len, "cpu%d %u %u %u %lu\n",
			i,
			hz_to_std(kstat.per_cpu_user[cpu_logical_map(i)]),
			hz_to_std(kstat.per_cpu_nice[cpu_logical_map(i)]),
			hz_to_std(kstat.per_cpu_system[cpu_logical_map(i)]),
			jif - hz_to_std(  kstat.per_cpu_user[cpu_logical_map(i)] \
				   + kstat.per_cpu_nice[cpu_logical_map(i)] \
				   + kstat.per_cpu_system[cpu_logical_map(i)]));
	len += sprintf(page + len,
		"page %u %u\n"
		"swap %u %u\n"
		"intr %u",
			kstat.pgpgin >> 1,
			kstat.pgpgout >> 1,
			kstat.pswpin,
			kstat.pswpout,
			sum
	);
#if !defined(CONFIG_ARCH_S390)
	for (i = 0 ; i < NR_IRQS ; i++)
		len += sprintf(page + len, " %u", kstat_irqs(i));
#endif

	len += sprintf(page + len, "\ndisk_io: ");

	for (major = 0; major < DK_MAX_MAJOR; major++) {