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/*
* 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
* Simplified starting of init: Michael A. Griffith <grif@acm.org>
*/
#define __KERNEL_SYSCALLS__
#include <linux/config.h>
#include <linux/proc_fs.h>
#include <linux/devfs_fs_kernel.h>
#include <linux/unistd.h>
#include <linux/string.h>
#include <linux/ctype.h>
#include <linux/delay.h>
#include <linux/utsname.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/smp_lock.h>
#include <linux/blk.h>
#include <linux/hdreg.h>
#include <linux/iobuf.h>
#include <linux/bootmem.h>
#include <linux/tty.h>
#include <asm/io.h>
#include <asm/bugs.h>
#if defined(CONFIG_ARCH_S390)
#include <asm/s390mach.h>
#include <asm/ccwcache.h>
#endif
#ifdef CONFIG_PCI
#include <linux/pci.h>
#endif
#ifdef CONFIG_DIO
#include <linux/dio.h>
#endif
#ifdef CONFIG_ZORRO
#include <linux/zorro.h>
#endif
#ifdef CONFIG_MTRR
# include <asm/mtrr.h>
#endif
#ifdef CONFIG_NUBUS
#include <linux/nubus.h>
#endif
#ifdef CONFIG_ISAPNP
#include <linux/isapnp.h>
#endif
#ifdef CONFIG_IRDA
extern int irda_proto_init(void);
extern int irda_device_init(void);
#endif
#ifdef CONFIG_X86_LOCAL_APIC
#include <asm/smp.h>
#endif
/*
* 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__ < 91)
#error Sorry, your GCC is too old. It builds incorrect kernels.
#endif
extern char _stext, _etext;
extern char *linux_banner;
static int init(void *);
extern void init_IRQ(void);
extern void init_modules(void);
extern void sock_init(void);
extern void fork_init(unsigned long);
extern void mca_init(void);
extern void sbus_init(void);
extern void ppc_init(void);
extern void sysctl_init(void);
extern void signals_init(void);
extern int init_pcmcia_ds(void);
extern void free_initmem(void);
#ifdef CONFIG_TC
extern void tc_init(void);
#endif
extern void ecard_init(void);
#if defined(CONFIG_SYSVIPC)
extern void ipc_init(void);
#endif
#ifdef CONFIG_PERFMON
extern void perfmon_init(void);
#endif
/*
* Boot command-line arguments
*/
#define MAX_INIT_ARGS 8
#define MAX_INIT_ENVS 8
extern void time_init(void);
extern void softirq_init(void);
int rows, cols;
#ifdef CONFIG_BLK_DEV_INITRD
unsigned int real_root_dev; /* do_proc_dointvec cannot handle kdev_t */
#endif
int root_mountflags = MS_RDONLY;
char *execute_command;
char root_device_name[64];
static char * argv_init[MAX_INIT_ARGS+2] = { "init", NULL, };
static char * envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, };
static int __init profile_setup(char *str)
{
int par;
if (get_option(&str,&par)) prof_shift = par;
return 1;
}
__setup("profile=", profile_setup);
static struct dev_name_struct {
const char *name;
const int num;
} root_dev_names[] __initdata = {
{ "nfs", 0x00ff },
{ "hda", 0x0300 },
{ "hdb", 0x0340 },
{ "loop", 0x0700 },
{ "hdc", 0x1600 },
{ "hdd", 0x1640 },
{ "hde", 0x2100 },
{ "hdf", 0x2140 },
{ "hdg", 0x2200 },
{ "hdh", 0x2240 },
{ "hdi", 0x3800 },
{ "hdj", 0x3840 },
{ "hdk", 0x3900 },
{ "hdl", 0x3940 },
{ "hdm", 0x5800 },
{ "hdn", 0x5840 },
{ "hdo", 0x5900 },
{ "hdp", 0x5940 },
{ "hdq", 0x5A00 },
{ "hdr", 0x5A40 },
{ "hds", 0x5B00 },
{ "hdt", 0x5B40 },
{ "sda", 0x0800 },
{ "sdb", 0x0810 },
{ "sdc", 0x0820 },
{ "sdd", 0x0830 },
{ "sde", 0x0840 },
{ "sdf", 0x0850 },
{ "sdg", 0x0860 },
{ "sdh", 0x0870 },
{ "sdi", 0x0880 },
{ "sdj", 0x0890 },
{ "sdk", 0x08a0 },
{ "sdl", 0x08b0 },
{ "sdm", 0x08c0 },
{ "sdn", 0x08d0 },
{ "sdo", 0x08e0 },
{ "sdp", 0x08f0 },
{ "ada", 0x1c00 },
{ "adb", 0x1c10 },
{ "adc", 0x1c20 },
{ "add", 0x1c30 },
{ "ade", 0x1c40 },
{ "fd", 0x0200 },
{ "md", 0x0900 },
{ "xda", 0x0d00 },
{ "xdb", 0x0d40 },
{ "ram", 0x0100 },
{ "scd", 0x0b00 },
{ "mcd", 0x1700 },
{ "cdu535", 0x1800 },
{ "sonycd", 0x1800 },
{ "aztcd", 0x1d00 },
{ "cm206cd", 0x2000 },
{ "gscd", 0x1000 },
{ "sbpcd", 0x1900 },
{ "eda", 0x2400 },
{ "edb", 0x2440 },
{ "pda", 0x2d00 },
{ "pdb", 0x2d10 },
{ "pdc", 0x2d20 },
{ "pdd", 0x2d30 },
{ "pcd", 0x2e00 },
{ "pf", 0x2f00 },
{ "apblock", APBLOCK_MAJOR << 8},
{ "ddv", DDV_MAJOR << 8},
{ "jsfd", JSFD_MAJOR << 8},
#if defined(CONFIG_ARCH_S390)
{ "dasda", (DASD_MAJOR << MINORBITS) },
{ "dasdb", (DASD_MAJOR << MINORBITS) + (1 << 2) },
{ "dasdc", (DASD_MAJOR << MINORBITS) + (2 << 2) },
{ "dasdd", (DASD_MAJOR << MINORBITS) + (3 << 2) },
{ "dasde", (DASD_MAJOR << MINORBITS) + (4 << 2) },
{ "dasdf", (DASD_MAJOR << MINORBITS) + (5 << 2) },
{ "dasdg", (DASD_MAJOR << MINORBITS) + (6 << 2) },
{ "dasdh", (DASD_MAJOR << MINORBITS) + (7 << 2) },
#endif
#if defined(CONFIG_BLK_CPQ_DA) || defined(CONFIG_BLK_CPQ_DA_MODULE)
{ "ida/c0d0p",0x4800 },
{ "ida/c0d1p",0x4810 },
{ "ida/c0d2p",0x4820 },
{ "ida/c0d3p",0x4830 },
{ "ida/c0d4p",0x4840 },
{ "ida/c0d5p",0x4850 },
{ "ida/c0d6p",0x4860 },
{ "ida/c0d7p",0x4870 },
{ "ida/c0d8p",0x4880 },
{ "ida/c0d9p",0x4890 },
{ "ida/c0d10p",0x48A0 },
{ "ida/c0d11p",0x48B0 },
{ "ida/c0d12p",0x48C0 },
{ "ida/c0d13p",0x48D0 },
{ "ida/c0d14p",0x48E0 },
{ "ida/c0d15p",0x48F0 },
#endif
#if defined(CONFIG_BLK_CPQ_CISS_DA) || defined(CONFIG_BLK_CPQ_CISS_DA_MODULE)
{ "cciss/c0d0p",0x6800 },
{ "cciss/c0d1p",0x6810 },
{ "cciss/c0d2p",0x6820 },
{ "cciss/c0d3p",0x6830 },
{ "cciss/c0d4p",0x6840 },
{ "cciss/c0d5p",0x6850 },
{ "cciss/c0d6p",0x6860 },
{ "cciss/c0d7p",0x6870 },
{ "cciss/c0d8p",0x6880 },
{ "cciss/c0d9p",0x6890 },
{ "cciss/c0d10p",0x68A0 },
{ "cciss/c0d11p",0x68B0 },
{ "cciss/c0d12p",0x68C0 },
{ "cciss/c0d13p",0x68D0 },
{ "cciss/c0d14p",0x68E0 },
{ "cciss/c0d15p",0x68F0 },
#endif
{ "nftla", 0x5d00 },
{ "nftlb", 0x5d10 },
{ "nftlc", 0x5d20 },
{ "nftld", 0x5d30 },
{ "ftla", 0x2c00 },
{ "ftlb", 0x2c08 },
{ "ftlc", 0x2c10 },
{ "ftld", 0x2c18 },
{ "mtdblock", 0x1f00 },
{ NULL, 0 }
};
kdev_t __init name_to_kdev_t(char *line)
{
int base = 0;
if (strncmp(line,"/dev/",5) == 0) {
struct dev_name_struct *dev = root_dev_names;
line += 5;
do {
int len = strlen(dev->name);
if (strncmp(line,dev->name,len) == 0) {
line += len;
base = dev->num;
break;
}
dev++;
} while (dev->name);
}
return to_kdev_t(base + simple_strtoul(line,NULL,base?10:16));
}
static int __init root_dev_setup(char *line)
{
int i;
char ch;
ROOT_DEV = name_to_kdev_t(line);
memset (root_device_name, 0, sizeof root_device_name);
if (strncmp (line, "/dev/", 5) == 0) line += 5;
for (i = 0; i < sizeof root_device_name - 1; ++i)
{
ch = line[i];
if ( isspace (ch) || (ch == ',') || (ch == '\0') ) break;
root_device_name[i] = ch;
}
return 1;
}
__setup("root=", root_dev_setup);
static int __init checksetup(char *line)
{
struct kernel_param *p;
p = &__setup_start;
do {
int n = strlen(p->str);
if (!strncmp(line,p->str,n)) {
if (p->setup_func(line+n))
return 1;
}
p++;
} while (p < &__setup_end);
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_jiffy = (1<<12);
/* This is the number of bits of precision for the loops_per_jiffy. Each
bit takes on average 1.5/HZ seconds. This (like the original) is a little
better than 1% */
#define LPS_PREC 8
void __init calibrate_delay(void)
{
unsigned long ticks, loopbit;
int lps_precision = LPS_PREC;
loops_per_jiffy = (1<<12);
printk("Calibrating delay loop... ");
while (loops_per_jiffy <<= 1) {
/* wait for "start of" clock tick */
ticks = jiffies;
while (ticks == jiffies)
/* nothing */;
/* Go .. */
ticks = jiffies;
__delay(loops_per_jiffy);
ticks = jiffies - ticks;
if (ticks)
break;
}
/* Do a binary approximation to get loops_per_jiffy set to equal one clock
(up to lps_precision bits) */
loops_per_jiffy >>= 1;
loopbit = loops_per_jiffy;
while ( lps_precision-- && (loopbit >>= 1) ) {
loops_per_jiffy |= loopbit;
ticks = jiffies;
while (ticks == jiffies);
ticks = jiffies;
__delay(loops_per_jiffy);
if (jiffies != ticks) /* longer than 1 tick */
loops_per_jiffy &= ~loopbit;
}
/* Round the value and print it */
printk("%lu.%02lu BogoMIPS\n",
loops_per_jiffy/(500000/HZ),
(loops_per_jiffy/(5000/HZ)) % 100);
}
static int __init readonly(char *str)
{
if (*str)
return 0;
root_mountflags |= MS_RDONLY;
return 1;
}
static int __init readwrite(char *str)
{
if (*str)
return 0;
root_mountflags &= ~MS_RDONLY;
return 1;
}
static int __init debug_kernel(char *str)
{
if (*str)
return 0;
console_loglevel = 10;
return 1;
}
static int __init quiet_kernel(char *str)
{
if (*str)
return 0;
console_loglevel = 4;
return 1;
}
__setup("ro", readonly);
__setup("rw", readwrite);
__setup("debug", debug_kernel);
__setup("quiet", quiet_kernel);
/*
* This is a simple kernel command line parsing function: it parses
* the command line, and fills in the arguments/environment to init
* as appropriate. Any cmd-line option is taken to be an environment
* variable if it contains the character '='.
*
* This routine also checks for options meant for the kernel.
* These options are not given to init - they are for internal kernel use only.
*/
static void __init parse_options(char *line)
{
char *next,*quote;
int args, envs;
if (!*line)
return;
args = 0;
envs = 1; /* TERM is set to 'linux' by default */
next = line;
while ((line = next) != NULL) {
quote = strchr(line,'"');
next = strchr(line, ' ');
while (next != NULL && quote != NULL && quote < next) {
/* we found a left quote before the next blank
* now we have to find the matching right quote
*/
next = strchr(quote+1, '"');
if (next != NULL) {
quote = strchr(next+1, '"');
next = strchr(next+1, ' ');
}
}
if (next != NULL)
*next++ = 0;
if (!strncmp(line,"init=",5)) {
line += 5;
execute_command = line;
/* In case LILO is going to boot us with default command line,
* it prepends "auto" before the whole cmdline which makes
* the shell think it should execute a script with such name.
* So we ignore all arguments entered _before_ init=... [MJ]
*/
args = 0;
continue;
}
if (checksetup(line))
continue;
/*
* Then check if it's an environment variable or
* an option.
*/
if (strchr(line,'=')) {
if (envs >= MAX_INIT_ENVS)
break;
envp_init[++envs] = line;
} else {
if (args >= MAX_INIT_ARGS)
break;
if (*line)
argv_init[++args] = line;
}
}
argv_init[args+1] = NULL;
envp_init[envs+1] = NULL;
}
extern void setup_arch(char **);
extern void cpu_idle(void);
unsigned long wait_init_idle;
#ifndef CONFIG_SMP
#ifdef CONFIG_X86_LOCAL_APIC
static void __init smp_init(void)
{
APIC_init_uniprocessor();
}
#else
#define smp_init() do { } while (0)
#endif
#else
/* Called by boot processor to activate the rest. */
static void __init smp_init(void)
{
/* Get other processors into their bootup holding patterns. */
smp_boot_cpus();
wait_init_idle = cpu_online_map;
clear_bit(current->processor, &wait_init_idle); /* Don't wait on me! */
smp_threads_ready=1;
smp_commence();
/* Wait for the other cpus to set up their idle processes */
printk("Waiting on wait_init_idle (map = 0x%lx)\n", wait_init_idle);
while (wait_init_idle) {
cpu_relax();
barrier();
}
printk("All processors have done init_idle\n");
}
#endif
/*
* We need to finalize in a non-__init function or else race conditions
* between the root thread and the init thread may cause start_kernel to
* be reaped by free_initmem before the root thread has proceeded to
* cpu_idle.
*/
static void rest_init(void)
{
kernel_thread(init, NULL, CLONE_FS | CLONE_FILES | CLONE_SIGNAL);
unlock_kernel();
current->need_resched = 1;
cpu_idle();
}
/*
* Activate the first processor.
*/
asmlinkage void __init start_kernel(void)
{
char * command_line;
unsigned long mempages;
extern char saved_command_line[];
/*
* Interrupts are still disabled. Do necessary setups, then
* enable them
*/
lock_kernel();
printk(linux_banner);
setup_arch(&command_line);
printk("Kernel command line: %s\n", saved_command_line);
parse_options(command_line);
trap_init();
init_IRQ();
sched_init();
softirq_init();
time_init();
/*
* HACK ALERT! This is early. We're enabling the console before
* we've done PCI setups etc, and console_init() must be aware of
* this. But we do want output early, in case something goes wrong.
*/
console_init();
#ifdef CONFIG_MODULES
init_modules();
#endif
if (prof_shift) {
unsigned int size;
/* only text is profiled */
prof_len = (unsigned long) &_etext - (unsigned long) &_stext;
prof_len >>= prof_shift;
size = prof_len * sizeof(unsigned int) + PAGE_SIZE-1;
prof_buffer = (unsigned int *) alloc_bootmem(size);
}
kmem_cache_init();
sti();
calibrate_delay();
#ifdef CONFIG_BLK_DEV_INITRD
if (initrd_start && !initrd_below_start_ok &&
initrd_start < min_low_pfn << PAGE_SHIFT) {
printk(KERN_CRIT "initrd overwritten (0x%08lx < 0x%08lx) - "
"disabling it.\n",initrd_start,min_low_pfn << PAGE_SHIFT);
initrd_start = 0;
}
#endif
mem_init();
kmem_cache_sizes_init();
pgtable_cache_init();
#ifdef CONFIG_PERFMON
perfmon_init();
#endif
mempages = num_physpages;
fork_init(mempages);
proc_caches_init();
vfs_caches_init(mempages);
buffer_init(mempages);
page_cache_init(mempages);
#if defined(CONFIG_ARCH_S390)
ccwcache_init();
#endif
signals_init();
#ifdef CONFIG_PROC_FS
proc_root_init();
#endif
#if defined(CONFIG_SYSVIPC)
ipc_init();
#endif
check_bugs();
printk("POSIX conformance testing by UNIFIX\n");
/*
* We count on the initial thread going ok
* Like idlers init is an unlocked kernel thread, which will
* make syscalls (and thus be locked).
*/
smp_init();
rest_init();
}
#ifdef CONFIG_BLK_DEV_INITRD
static int do_linuxrc(void * shell)
{
static char *argv[] = { "linuxrc", NULL, };
close(0);close(1);close(2);
setsid();
(void) open("/dev/console",O_RDWR,0);
(void) dup(0);
(void) dup(0);
return execve(shell, argv, envp_init);
}
#endif
struct task_struct *child_reaper = &init_task;
static void __init do_initcalls(void)
{
initcall_t *call;
call = &__initcall_start;
do {
(*call)();
call++;
} while (call < &__initcall_end);
/* Make sure there is no pending stuff from the initcall sequence */
flush_scheduled_tasks();
}
/*
* Ok, the machine is now initialized. None of the devices
* have been touched yet, but the CPU subsystem is up and
* running, and memory and process management works.
*
* Now we can finally start doing some real work..
*/
static void __init do_basic_setup(void)
{
/*
* Tell the world that we're going to be the grim
* reaper of innocent orphaned children.
*
* We don't want people to have to make incorrect
* assumptions about where in the task array this
* can be found.
*/
child_reaper = current;
#if defined(CONFIG_MTRR) /* Do this after SMP initialization */
/*
* We should probably create some architecture-dependent "fixup after
* everything is up" style function where this would belong better
* than in init/main.c..
*/
mtrr_init();
#endif
#ifdef CONFIG_SYSCTL
sysctl_init();
#endif
/*
* Ok, at this point all CPU's should be initialized, so
* we can start looking into devices..
*/
#if defined(CONFIG_ARCH_S390)
s390_init_machine_check();
#endif
#ifdef CONFIG_PCI
pci_init();
#endif
#ifdef CONFIG_SBUS
sbus_init();
#endif
#if defined(CONFIG_PPC)
ppc_init();
#endif
#ifdef CONFIG_MCA
mca_init();
#endif
#ifdef CONFIG_ARCH_ACORN
ecard_init();
#endif
#ifdef CONFIG_ZORRO
zorro_init();
#endif
#ifdef CONFIG_DIO
dio_init();
#endif
#ifdef CONFIG_NUBUS
nubus_init();
#endif
#ifdef CONFIG_ISAPNP
isapnp_init();
#endif
#ifdef CONFIG_TC
tc_init();
#endif
/* Networking initialization needs a process context */
sock_init();
start_context_thread();
do_initcalls();
#ifdef CONFIG_IRDA
irda_proto_init();
irda_device_init(); /* Must be done after protocol initialization */
#endif
#ifdef CONFIG_PCMCIA
init_pcmcia_ds(); /* Do this last */
#endif
}
extern void rd_load(void);
extern void initrd_load(void);
/*
* Prepare the namespace - decide what/where to mount, load ramdisks, etc.
*/
static void prepare_namespace(void)
{
#ifdef CONFIG_BLK_DEV_INITRD
int real_root_mountflags = root_mountflags;
if (!initrd_start)
mount_initrd = 0;
if (mount_initrd)
root_mountflags &= ~MS_RDONLY;
real_root_dev = ROOT_DEV;
#endif
#ifdef CONFIG_BLK_DEV_RAM
#ifdef CONFIG_BLK_DEV_INITRD
if (mount_initrd)
initrd_load();
else
#endif
rd_load();
#endif
/* Mount the root filesystem.. */
mount_root();
mount_devfs_fs ();
#ifdef CONFIG_BLK_DEV_INITRD
root_mountflags = real_root_mountflags;
if (mount_initrd && ROOT_DEV != real_root_dev
&& MAJOR(ROOT_DEV) == RAMDISK_MAJOR && MINOR(ROOT_DEV) == 0) {
int error;
int i, pid;
pid = kernel_thread(do_linuxrc, "/linuxrc", SIGCHLD);
if (pid > 0) {
while (pid != wait(&i)) {
current->policy |= SCHED_YIELD;
schedule();
}
}
if (MAJOR(real_root_dev) != RAMDISK_MAJOR
|| MINOR(real_root_dev) != 0) {
error = change_root(real_root_dev,"/initrd");
if (error)
printk(KERN_ERR "Change root to /initrd: "
"error %d\n",error);
}
}
#endif
}
static int init(void * unused)
{
lock_kernel();
do_basic_setup();
prepare_namespace();
/*
* Ok, we have completed the initial bootup, and
* we're essentially up and running. Get rid of the
* initmem segments and start the user-mode stuff..
*/
free_initmem();
unlock_kernel();
if (open("/dev/console", O_RDWR, 0) < 0)
printk("Warning: unable to open an initial console.\n");
(void) dup(0);
(void) dup(0);
/*
* We try each of these until one succeeds.
*
* The Bourne shell can be used instead of init if we are
* trying to recover a really broken machine.
*/
if (execute_command)
execve(execute_command,argv_init,envp_init);
execve("/sbin/init",argv_init,envp_init);
execve("/etc/init",argv_init,envp_init);
execve("/bin/init",argv_init,envp_init);
execve("/bin/sh",argv_init,envp_init);
panic("No init found. Try passing init= option to kernel.");
}
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