main.c

GNU Mach 微内核源代码, 基于美国卡内基美隆大学的 Mach 研究项目

/*
 *  linux/init/main.c
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 *
 *  GK 2/5/95  -  Changed to support mounting root fs via NFS
 *  Added initrd & change_root: Werner Almesberger & Hans Lermen, Feb '96
 *  Moan early if gcc is old, avoiding bogus kernels - Paul Gortmaker, May '96
 */

#define __KERNEL_SYSCALLS__
#include <stdarg.h>

#include <asm/system.h>
#include <asm/io.h>

#include <linux/types.h>
#include <linux/fcntl.h>
#include <linux/config.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/tty.h>
#include <linux/head.h>
#include <linux/unistd.h>
#include <linux/string.h>
#include <linux/timer.h>
#include <linux/fs.h>
#include <linux/ctype.h>
#include <linux/delay.h>
#include <linux/utsname.h>
#include <linux/ioport.h>
#include <linux/hdreg.h>
#include <linux/mm.h>
#include <linux/major.h>
#include <linux/blk.h>
#ifdef CONFIG_ROOT_NFS
#include <linux/nfs_fs.h>
#endif
#ifdef CONFIG_MTRR
#include <asm/mtrr.h>
#endif

#include <asm/bugs.h>

/*
 * Versions of gcc older than that listed below may actually compile
 * and link okay, but the end product can have subtle run time bugs.
 * To avoid associated bogus bug reports, we flatly refuse to compile
 * with a gcc that is known to be too old from the very beginning.
 */
#if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 6)
#error sorry, your GCC is too old. It builds incorrect kernels.
#endif

extern char _stext, _etext;
extern const char *linux_banner;

static char printbuf[1024];

extern int console_loglevel;

static int init(void *);
extern int bdflush(void *);
extern int kswapd(void *);
extern void kswapd_setup(void);

extern void init_IRQ(void);
extern void init_modules(void);
extern long console_init(long, long);
extern long kmalloc_init(long,long);
extern void sock_init(void);
extern unsigned long pci_init(unsigned long, unsigned long);
extern void sysctl_init(void);

extern void no_scroll(char *str, int *ints);
extern void swap_setup(char *str, int *ints);
extern void buff_setup(char *str, int *ints);
extern void panic_setup(char *str, int *ints);
extern void bmouse_setup(char *str, int *ints);
extern void msmouse_setup(char *str, int *ints);
extern void lp_setup(char *str, int *ints);
extern void eth_setup(char *str, int *ints);
extern void xd_setup(char *str, int *ints);
extern void xd_manual_geo_init(char *str, int *ints);
extern void floppy_setup(char *str, int *ints);
extern void st_setup(char *str, int *ints);
extern void st0x_setup(char *str, int *ints);
extern void advansys_setup(char *str, int *ints);
extern void tmc8xx_setup(char *str, int *ints);
extern void t128_setup(char *str, int *ints);
extern void pas16_setup(char *str, int *ints);
extern void generic_NCR5380_setup(char *str, int *intr);
extern void generic_NCR53C400_setup(char *str, int *intr);
extern void aha152x_setup(char *str, int *ints);
extern void aha1542_setup(char *str, int *ints);
extern void gdth_setup(char *str, int *ints);
extern void aic7xxx_setup(char *str, int *ints);
extern void AM53C974_setup(char *str, int *ints);
extern void BusLogic_Setup(char *str, int *ints);
extern void ncr53c8xx_setup(char *str, int *ints);
extern void eata2x_setup(char *str, int *ints);
extern void u14_34f_setup(char *str, int *ints);
extern void fdomain_setup(char *str, int *ints);
extern void in2000_setup(char *str, int *ints);
extern void NCR53c406a_setup(char *str, int *ints);
extern void wd7000_setup(char *str, int *ints);
extern void ppa_setup(char *str, int *ints);
extern void scsi_luns_setup(char *str, int *ints);
extern void sound_setup(char *str, int *ints);
extern void apm_setup(char *str, int *ints);
extern void reboot_setup(char *str, int *ints);
#ifdef CONFIG_CDU31A
extern void cdu31a_setup(char *str, int *ints);
#endif CONFIG_CDU31A
#ifdef CONFIG_MCD
extern void mcd_setup(char *str, int *ints);
#endif CONFIG_MCD
#ifdef CONFIG_MCDX
extern void mcdx_setup(char *str, int *ints);
#endif CONFIG_MCDX
#ifdef CONFIG_SBPCD
extern void sbpcd_setup(char *str, int *ints);
#endif CONFIG_SBPCD
#ifdef CONFIG_AZTCD
extern void aztcd_setup(char *str, int *ints);
#endif CONFIG_AZTCD
#ifdef CONFIG_CDU535
extern void sonycd535_setup(char *str, int *ints);
#endif CONFIG_CDU535
#ifdef CONFIG_GSCD
extern void gscd_setup(char *str, int *ints);
#endif CONFIG_GSCD
#ifdef CONFIG_CM206
extern void cm206_setup(char *str, int *ints);
#endif CONFIG_CM206
#ifdef CONFIG_OPTCD
extern void optcd_setup(char *str, int *ints);
#endif CONFIG_OPTCD
#ifdef CONFIG_SJCD
extern void sjcd_setup(char *str, int *ints);
#endif CONFIG_SJCD
#ifdef CONFIG_ISP16_CDI
extern void isp16_setup(char *str, int *ints);
#endif CONFIG_ISP16_CDI
#ifdef CONFIG_BLK_DEV_RAM
static void ramdisk_start_setup(char *str, int *ints);
static void load_ramdisk(char *str, int *ints);
static void prompt_ramdisk(char *str, int *ints);
static void ramdisk_size(char *str, int *ints);
#ifdef CONFIG_BLK_DEV_INITRD
static void no_initrd(char *s,int *ints);
#endif
#endif CONFIG_BLK_DEV_RAM
#ifdef CONFIG_ISDN_DRV_ICN
extern void icn_setup(char *str, int *ints);
#endif
#ifdef CONFIG_ISDN_DRV_HISAX
extern void HiSax_setup(char *str, int *ints);
#endif
#ifdef CONFIG_ISDN_DRV_PCBIT
extern void pcbit_setup(char *str, int *ints);
#endif

#ifdef CONFIG_ATARIMOUSE
extern void atari_mouse_setup (char *str, int *ints);
#endif
#ifdef CONFIG_DMASOUND
extern void dmasound_setup (char *str, int *ints);
#endif
#ifdef CONFIG_ATARI_SCSI
extern void atari_scsi_setup (char *str, int *ints);
#endif
extern void wd33c93_setup (char *str, int *ints);
extern void gvp11_setup (char *str, int *ints);

#ifdef CONFIG_CYCLADES
extern void cy_setup(char *str, int *ints);
#endif
#ifdef CONFIG_DIGI
extern void pcxx_setup(char *str, int *ints);
#endif
#ifdef CONFIG_RISCOM8
extern void riscom8_setup(char *str, int *ints);
#endif
#ifdef CONFIG_SPECIALIX
extern void specialix_setup(char *str, int *ints);
#endif
#ifdef CONFIG_BAYCOM
extern void baycom_setup(char *str, int *ints);
#endif

#ifdef CONFIG_PARIDE_PD
extern void pd_setup(char *str, int *ints);
#endif
#ifdef CONFIG_PARIDE_PF
extern void pf_setup(char *str, int *ints);
#endif
#ifdef CONFIG_PARIDE_PT
extern void pt_setup(char *str, int *ints);
#endif
#ifdef CONFIG_PARIDE_PG
extern void pg_setup(char *str, int *ints);
#endif
#ifdef CONFIG_PARIDE_PCD
extern void pcd_setup(char *str, int *ints);
#endif

#if defined(CONFIG_SYSVIPC) || defined(CONFIG_KERNELD)
extern void ipc_init(void);
#endif

/*
 * Boot command-line arguments
 */
#define MAX_INIT_ARGS 8
#define MAX_INIT_ENVS 8

extern void time_init(void);

static unsigned long memory_start = 0;
static unsigned long memory_end = 0;

int rows, cols;

#ifdef CONFIG_BLK_DEV_RAM
extern int rd_doload;		/* 1 = load ramdisk, 0 = don't load */
extern int rd_prompt;		/* 1 = prompt for ramdisk, 0 = don't prompt */
extern int rd_size;		/* Size of the ramdisk(s) */
extern int rd_image_start;	/* starting block # of image */
#ifdef CONFIG_BLK_DEV_INITRD
kdev_t real_root_dev;
#endif
#endif

int root_mountflags = MS_RDONLY;
char *execute_command = 0;

#ifdef CONFIG_ROOT_NFS
char nfs_root_name[NFS_ROOT_NAME_LEN] = { "default" };
char nfs_root_addrs[NFS_ROOT_ADDRS_LEN] = { "" };
#endif

extern void dquot_init(void);

static char * argv_init[MAX_INIT_ARGS+2] = { "init", NULL, };
static char * envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, };

static char * argv_rc[] = { "/bin/sh", NULL };
static char * envp_rc[] = { "HOME=/", "TERM=linux", NULL };

static char * argv[] = { "-/bin/sh",NULL };
static char * envp[] = { "HOME=/usr/root", "TERM=linux", NULL };

char *get_options(char *str, int *ints)
{
	char *cur = str;
	int i=1;

	while (cur && isdigit(*cur) && i <= 10) {
		ints[i++] = simple_strtoul(cur,NULL,0);
		if ((cur = strchr(cur,',')) != NULL)
			cur++;
	}
	ints[0] = i-1;
	return(cur);
}

static void profile_setup(char *str, int *ints)
{
	if (ints[0] > 0)
		prof_shift = (unsigned long) ints[1];
	else
#ifdef CONFIG_PROFILE_SHIFT
		prof_shift = CONFIG_PROFILE_SHIFT;
#else
		prof_shift = 2;
#endif
}

struct kernel_param {
	const char *str;
	void (*setup_func)(char *, int *);
} ;

struct kernel_param bootsetups[] = {
	{ "reserve=", reserve_setup },
	{ "profile=", profile_setup },
#ifdef CONFIG_BLK_DEV_RAM
	{ "ramdisk_start=", ramdisk_start_setup },
	{ "load_ramdisk=", load_ramdisk },
	{ "prompt_ramdisk=", prompt_ramdisk },
	{ "ramdisk=", ramdisk_size },
	{ "ramdisk_size=", ramdisk_size },
#ifdef CONFIG_BLK_DEV_INITRD
	{ "noinitrd", no_initrd },
#endif
#endif
	{ "swap=", swap_setup },
	{ "buff=", buff_setup },
	{ "panic=", panic_setup },
	{ "no-scroll", no_scroll },
#ifdef CONFIG_BUGi386
	{ "no-hlt", no_halt },
	{ "no387", no_387 },
	{ "reboot=", reboot_setup },
#endif
#ifdef CONFIG_INET
	{ "ether=", eth_setup },
#endif
#ifdef CONFIG_PRINTER
        { "lp=", lp_setup },
#endif
#ifdef CONFIG_SCSI
	{ "max_scsi_luns=", scsi_luns_setup },
#endif
#ifdef CONFIG_SCSI_ADVANSYS
	{ "advansys=", advansys_setup },
#endif
#if defined(CONFIG_BLK_DEV_HD)
	{ "hd=", hd_setup },
#endif
#ifdef CONFIG_CHR_DEV_ST
	{ "st=", st_setup },
#endif
#ifdef CONFIG_BUSMOUSE
	{ "bmouse=", bmouse_setup },
#endif
#ifdef CONFIG_MS_BUSMOUSE
	{ "msmouse=", msmouse_setup },
#endif
#ifdef CONFIG_SCSI_SEAGATE
	{ "st0x=", st0x_setup },
	{ "tmc8xx=", tmc8xx_setup },
#endif
#ifdef CONFIG_SCSI_T128
	{ "t128=", t128_setup },
#endif
#ifdef CONFIG_SCSI_PAS16
	{ "pas16=", pas16_setup },
#endif
#ifdef CONFIG_SCSI_GENERIC_NCR5380
	{ "ncr5380=", generic_NCR5380_setup },
	{ "ncr53c400=", generic_NCR53C400_setup },
#endif
#ifdef CONFIG_SCSI_AHA152X
	{ "aha152x=", aha152x_setup},
#endif
#ifdef CONFIG_SCSI_AHA1542
	{ "aha1542=", aha1542_setup},
#endif
#ifdef CONFIG_SCSI_GDTH
	{ "gdth=", gdth_setup},
#endif
#ifdef CONFIG_SCSI_AIC7XXX
	{ "aic7xxx=", aic7xxx_setup},
#endif
#ifdef CONFIG_SCSI_BUSLOGIC
	{ "BusLogic=", BusLogic_Setup},
#endif
#ifdef CONFIG_SCSI_NCR53C8XX
	{ "ncr53c8xx=", ncr53c8xx_setup},
#endif
#ifdef CONFIG_SCSI_EATA
	{ "eata=", eata2x_setup},
#endif
#ifdef CONFIG_SCSI_U14_34F
	{ "u14-34f=", u14_34f_setup},
#endif
#ifdef CONFIG_SCSI_AM53C974
        { "AM53C974=", AM53C974_setup},
#endif
#ifdef CONFIG_SCSI_NCR53C406A
	{ "ncr53c406a=", NCR53c406a_setup},
#endif
#ifdef CONFIG_SCSI_FUTURE_DOMAIN
	{ "fdomain=", fdomain_setup},
#endif
#ifdef CONFIG_SCSI_IN2000
	{ "in2000=", in2000_setup},
#endif
#ifdef CONFIG_SCSI_7000FASST
	{ "wd7000=", wd7000_setup},
#endif
#ifdef CONFIG_SCSI_PPA
        { "ppa=", ppa_setup },
#endif
#ifdef CONFIG_BLK_DEV_XD
	{ "xd=", xd_setup },
	{ "xd_geo=", xd_manual_geo_init },
#endif
#ifdef CONFIG_BLK_DEV_FD
	{ "floppy=", floppy_setup },
#endif
#ifdef CONFIG_CDU31A
	{ "cdu31a=", cdu31a_setup },
#endif CONFIG_CDU31A
#ifdef CONFIG_MCD
	{ "mcd=", mcd_setup },
#endif CONFIG_MCD
#ifdef CONFIG_MCDX
	{ "mcdx=", mcdx_setup },
#endif CONFIG_MCDX
#ifdef CONFIG_SBPCD
	{ "sbpcd=", sbpcd_setup },
#endif CONFIG_SBPCD
#ifdef CONFIG_AZTCD
	{ "aztcd=", aztcd_setup },
#endif CONFIG_AZTCD
#ifdef CONFIG_CDU535
	{ "sonycd535=", sonycd535_setup },
#endif CONFIG_CDU535
#ifdef CONFIG_GSCD
	{ "gscd=", gscd_setup },
#endif CONFIG_GSCD
#ifdef CONFIG_CM206
	{ "cm206=", cm206_setup },
#endif CONFIG_CM206
#ifdef CONFIG_OPTCD
	{ "optcd=", optcd_setup },
#endif CONFIG_OPTCD
#ifdef CONFIG_SJCD
	{ "sjcd=", sjcd_setup },
#endif CONFIG_SJCD
#ifdef CONFIG_ISP16_CDI
	{ "isp16=", isp16_setup },
#endif CONFIG_ISP16_CDI
#ifdef CONFIG_SOUND
	{ "sound=", sound_setup },
#endif
#ifdef CONFIG_ISDN_DRV_ICN
	{ "icn=", icn_setup },
#endif
#ifdef CONFIG_ISDN_DRV_HISAX
       { "hisax=", HiSax_setup },
       { "HiSax=", HiSax_setup },
#endif
#ifdef CONFIG_ISDN_DRV_PCBIT
	{ "pcbit=", pcbit_setup },
#endif
#ifdef CONFIG_ATARIMOUSE
	{ "atamouse=", atari_mouse_setup },
#endif
#ifdef CONFIG_DMASOUND
	{ "dmasound=", dmasound_setup },
#endif
#ifdef CONFIG_ATARI_SCSI
	{ "atascsi=", atari_scsi_setup },
#endif
#if defined(CONFIG_A3000_SCSI) || defined(CONFIG_A2091_SCSI) \
	    || defined(CONFIG_GVP11_SCSI)
	{ "wd33c93=", wd33c93_setup },
#endif
#if defined(CONFIG_GVP11_SCSI)
	{ "gvp11=", gvp11_setup },
#endif
#ifdef CONFIG_CYCLADES
	{ "cyclades=", cy_setup },
#endif
#ifdef CONFIG_DIGI
	{ "digi=", pcxx_setup },
#endif
#ifdef CONFIG_RISCOM8
	{ "riscom8=", riscom8_setup },
#endif
#ifdef CONFIG_SPECIALIX
	{ "specialix=", specialix_setup },
#endif
#ifdef CONFIG_BAYCOM
	{ "baycom=", baycom_setup },
#endif
#ifdef CONFIG_APM
	{ "apm=", apm_setup },
#endif
	{ 0, 0 }
};

static struct kernel_param raw_params[] = {

#ifdef CONFIG_PARIDE_PD
       { "pd.", pd_setup },
#endif
#ifdef CONFIG_PARIDE_PCD
       { "pcd.", pcd_setup },
#endif
#ifdef CONFIG_PARIDE_PF
       { "pf.", pf_setup },
#endif
#ifdef CONFIG_PARIDE_PT
       { "pt.", pt_setup },
#endif
#ifdef CONFIG_PARIDE_PG
       { "pg.", pg_setup },
#endif
       { 0, 0 }
} ;


#ifdef CONFIG_BLK_DEV_RAM
static void ramdisk_start_setup(char *str, int *ints)
{
   if (ints[0] > 0 && ints[1] >= 0)
      rd_image_start = ints[1];
}

static void load_ramdisk(char *str, int *ints)
{
   if (ints[0] > 0 && ints[1] >= 0)
      rd_doload = ints[1] & 3;
}

static void prompt_ramdisk(char *str, int *ints)
{
   if (ints[0] > 0 && ints[1] >= 0)
      rd_prompt = ints[1] & 1;
}

static void ramdisk_size(char *str, int *ints)
{
	if (ints[0] > 0 && ints[1] >= 0)
		rd_size = ints[1];
}

#endif

static int checksetup(char *line)
{
	int i = 0;
	int ints[11];

#ifdef CONFIG_BLK_DEV_IDE
	/* ide driver needs the basic string, rather than pre-processed values */
	if (!strncmp(line,"ide",3) || (!strncmp(line,"hd",2) && line[2] != '=')) {
		ide_setup(line);
		return 1;
	}
#endif
	while (bootsetups[i].str) {
		int n = strlen(bootsetups[i].str);
		if (!strncmp(line,bootsetups[i].str,n)) {
			bootsetups[i].setup_func(get_options(line+n,ints), ints);
			return 1;
		}
		i++;
	}

        for (i=0; raw_params[i].str; i++) {
                int n = strlen(raw_params[i].str);
                if (!strncmp(line,raw_params[i].str,n)) {
                        raw_params[i].setup_func(line+n, NULL);
                        return 1;
                }
        }

	return 0;
}

/* this should be approx 2 Bo*oMips to start (note initial shift), and will
   still work even if initially too large, it will just take slightly longer */
unsigned long loops_per_sec = (1<<12);

#if defined(__SMP__) && defined(__i386__)
unsigned long smp_loops_per_tick = 1000000;
#endif

/* This is the number of bits of precision for the loops_per_second.  Each
   bit takes on average 1.5/HZ seconds.  This (like the original) is a little
   better than 1% */
#define LPS_PREC 8