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/*
* linux/kernel/info.c
*
* Copyright (C) 1992 Darren Senn
*/
/* This implements the sysinfo() system call */
#include <linux/mm.h>
#include <linux/unistd.h>
#include <linux/swap.h>
#include <linux/smp_lock.h>
#include <asm/uaccess.h>
asmlinkage long sys_sysinfo(struct sysinfo *info)
{
struct sysinfo val;
memset((char *)&val, 0, sizeof(struct sysinfo));
cli();
val.uptime = jiffies / HZ;
val.loads[0] = avenrun[0] << (SI_LOAD_SHIFT - FSHIFT);
val.loads[1] = avenrun[1] << (SI_LOAD_SHIFT - FSHIFT);
val.loads[2] = avenrun[2] << (SI_LOAD_SHIFT - FSHIFT);
val.procs = nr_threads-1;
sti();
si_meminfo(&val);
si_swapinfo(&val);
{
unsigned long mem_total, sav_total;
unsigned int mem_unit, bitcount;
/* If the sum of all the available memory (i.e. ram + swap)
* is less than can be stored in a 32 bit unsigned long then
* we can be binary compatible with 2.2.x kernels. If not,
* well, in that case 2.2.x was broken anyways...
*
* -Erik Andersen <andersee@debian.org> */
mem_total = val.totalram + val.totalswap;
if (mem_total < val.totalram || mem_total < val.totalswap)
goto out;
bitcount = 0;
mem_unit = val.mem_unit;
while (mem_unit > 1) {
bitcount++;
mem_unit >>= 1;
sav_total = mem_total;
mem_total <<= 1;
if (mem_total < sav_total)
goto out;
}
/* If mem_total did not overflow, multiply all memory values by
* val.mem_unit and set it to 1. This leaves things compatible
* with 2.2.x, and also retains compatibility with earlier 2.4.x
* kernels... */
val.mem_unit = 1;
val.totalram <<= bitcount;
val.freeram <<= bitcount;
val.sharedram <<= bitcount;
val.bufferram <<= bitcount;
val.totalswap <<= bitcount;
val.freeswap <<= bitcount;
val.totalhigh <<= bitcount;
val.freehigh <<= bitcount;
}
out:
if (copy_to_user(info, &val, sizeof(struct sysinfo)))
return -EFAULT;
return 0;
}
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