/*
 *  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/file.h>
#include <linux/tty.h>
#include <linux/rcupdate.h>
#include <linux/elevator.h>
#include <linux/blkdev.h>
#include <linux/grsecurity.h>
#include <linux/smp.h>

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

/*
 * This is one of the first .c files built. Error out early
 * if we have compiler trouble..
 */
#if (__GNUC__ == 2 && __GNUC_MINOR__ == 96)
#ifdef CONFIG_FRAME_POINTER
#error This compiler cannot compile correctly with frame pointers enabled!
#error Go and grab a real compiler!
#endif
#endif

#if defined(CONFIG_ARCH_S390)
#include <asm/s390mach.h>
#include <asm/ccwcache.h>
#endif

#ifdef CONFIG_ACPI
#include <linux/acpi.h>
#endif

/* RSBAC: including rsbac_init declaration */
#ifdef CONFIG_RSBAC
#include <rsbac/aci.h>
#include <rsbac/debug.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_SYSTRACE
#include <linux/queue.h>
#include <asm/semaphore.h>
#include <linux/systrace.h>
#endif

#ifdef CONFIG_X86_LOCAL_APIC
#include <asm/smp.h>
#endif

#ifdef	CONFIG_KDB
#include <linux/kdb.h>
#endif	/* CONFIG_KDB */

/*
 * 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__ < 95)
#error Sorry, your GCC is too old. It builds incorrect kernels.
#endif

extern char _stext, _etext;
extern char *wolk_banner;
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 pte_chain_init(void);

extern void free_initmem(void);

#ifdef CONFIG_TC
extern void tc_init(void);
#endif

extern void ecard_init(void);
extern int nwd_boot_init(void);

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

extern void grsecurity_init(void);

/*
 * Boot command-line arguments
 */
#define MAX_INIT_ARGS 32
#define MAX_INIT_ENVS 32

extern void time_init(void);
extern void softirq_init(void);

int rows, cols;

char *execute_command;

static char * argv_init[MAX_INIT_ARGS+2] = { "init", NULL, };
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);

int disable_all_usb = 0;
static int __init no_usb(char * s)
{
	disable_all_usb = 1;
	return 1;
}
__setup("nousb", no_usb);


extern int max_recursive_link;
static int __init overflowmeharder(char * s)
{
	if (strstr(s,"overflowmeharder"))
		max_recursive_link = 8;
	return 0;
}
__setup("stack",overflowmeharder);

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("CPU#%d: Calibrating delay loop... ", smp_processor_id());
	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 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;
}

static int __init really_quiet_kernel(char *str)
{
	if (*str)
		return 0;
	console_loglevel = 0;
	return 1;
}

__setup("debug", debug_kernel);
__setup("quiet", quiet_kernel);
__setup("reallyquiet", really_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;
	char *peq;
	int oenvs, i;

	if (!*line)
		return;
	args = 0;
	envs = 1;	/* TERM is set to 'linux' by default */
	oenvs = envs;
	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 (!*line)
			continue;
#ifdef	CONFIG_KDB
		/* kdb=on, kdb=off, kdb=early */
		if (strncmp(line, "kdb=", 4) == 0) {
			if (strcmp(line+4, "on") == 0) {
				kdb_on = 1;
				continue;
			}
			if (strcmp(line+4, "off") == 0) {
				kdb_on = 0;
				continue;
			}
			if (strcmp(line+4, "early") == 0) {
				kdb_on = 1;
				kdb_flags |= KDB_FLAG_EARLYKDB;
				continue;
			}
			printk("Boot flag %s not recognised, assumed to be environment variable\n", line);
		}
#endif	/* CONFIG_KDB */
		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;
		
#ifdef CONFIG_RSBAC
		if(rsbac_parse_koptions(line))
		  continue;
#endif /* CONFIG_RSBAC */

		/*
		 * Then check if it's an environment variable or
		 * an option.
		 */
		if ((peq = strchr(line,'=')) != NULL) {
			/*
			 * Make sure we don't duplicate what's in the
			 * initial environment.  We don't check for
			 * duplicates in line since the user can sort
			 * that one out.
			 */
			for (i = 0; i <= oenvs; i++)
				if (strncmp(line,envp_init[i],peq-line) == 0) {
					envp_init[i] = line;
					break;
				}
			if (i <= oenvs)
				continue;
			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);
extern void disable_early_printk(void);

/* This is for oprofile to detect the APIC state */
#ifdef CONFIG_SMP
int enable_apic_up = 1;
#else
int enable_apic_up = 0; 
#endif

#ifndef CONFIG_SMP

#ifdef CONFIG_X86_LOCAL_APIC

int enable_apic_up_force;

void __init enable_apic_up_setup(void)
{
	enable_apic_up_force = 1;
	enable_apic_up = 1;
	skip_ioapic_setup = 0;
}

void __init disable_apic_up_setup(void)
{
	enable_apic_up_force = 1;
	enable_apic_up = 0;
	skip_ioapic_setup = 1;
}

static void __init smp_init(void)
{
	if (enable_apic_up)
		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();

	smp_threads_ready=1;
	smp_commence();
}

#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();
	cpu_idle();
}

/*
 *	Activate the first processor.
 */

asmlinkage void __init start_kernel(void)
{
	char * command_line;
	extern char saved_command_line[];
/*
 * Interrupts are still disabled. Do necessary setups, then
 * enable them
 */
	lock_kernel();
#ifdef CONFIG_WLI_EARLY_PRINTK
	register_early_consoles();
#endif
	printk(wolk_banner);
	printk(linux_banner);
	setup_arch(&command_line);
	printk("Kernel command line: %s\n", saved_command_line);
	parse_options(command_line);
	trap_init();
	rcu_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.
	 */
#ifdef CONFIG_EARLY_PRINTK
	disable_early_printk(); 
#endif
#ifdef CONFIG_WLI_EARLY_PRINTK
	unregister_early_consoles();
#endif
	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();
	pte_chain_init();

#ifdef	CONFIG_KDB
	kdb_init();
	if (KDB_FLAG(EARLYKDB)) {
		KDB_ENTER();
	}
#endif	/* CONFIG_KDB */

	/*
	 * For architectures that have highmem, num_mappedpages represents
	 * the amount of memory the kernel can use.  For other architectures
	 * it's the same as the total pages.  We need both numbers because
	 * some subsystems need to initialize based on how much memory the
	 * kernel can use.
	 */
	if (num_mappedpages == 0)
		num_mappedpages = num_physpages;
  
	fork_init(num_mappedpages);
	proc_caches_init();
	vfs_caches_init(num_physpages);
	buffer_init(num_physpages);
	page_cache_init(num_physpages);

	/*
	 *	We want to show current HZ value at boot time.
	 */
	printk("HZ: Currently used kernel timer frequency is: %d HZ\n", HZ);

	/*
	 *	We want to tell the user we are RMAPed.
	 */
	printk("RMAP: reverse mapping based VM v15l initialized. (C) 2004, Rik van Riel.\n");

	/*
	 *	We want to tell the user that we are doing lowlatency..
	 */
	printk("LOWLAT: Kernel low latency fixes enabled. (C) 2003, Andrea Arcangeli.\n");

	/*
	 *	We want to show if we use memory pools or not.
	 */
	#ifdef CONFIG_MEMORYPOOL
		printk("MEMPOOL: Memory Pools enabled. Copyright (C) 2001, Ingo Molnar.\n");
	#else
		printk("MEMPOOL: Memory Pools disabled. Copyright (C) 2001, Ingo Molnar.\n");
	#endif

	/*
	 *	We want to tell the user if we are doing kernel preemption or not.
	 */
	#ifdef CONFIG_PREEMPT
		printk("PREEMPT: Kernel preemption enabled. (C) 2003, Robert Love.\n");
	#else
		printk("PREEMPT: Kernel preemption disabled. (C) 2003, Robert Love.\n");
	#endif

	/*
	 *	We want to tell the user what read and write latency we are using.
	 */
	printk("ELEVATOR: read_latency: %d - write_latency: %d - max_bomb_segments: %d.\n", ELEVATOR_READ_LATENCY, ELEVATOR_WRITE_LATENCY, ELEVATOR_MAX_BOMB_SEGMENTS);
	printk("ELEVATOR: MAX_QUEUE_SECTORS: %d - MAX_NR_REQUESTS: %d.\n", MAX_QUEUE_SECTORS, MAX_NR_REQUESTS);

	#ifdef CONFIG_BLK_DEV_ELEVATOR_NOOP
		printk("ELEVATOR: You are using the NOOP Elevator. WARNING!!\n");
	#endif
	#ifdef CONFIG_BLK_DEV_ELEVATOR_LOWLAT
		printk("ELEVATOR: You are using the Low Latency Elevator. Fasten your seat belt :)\n");
	#endif

	/*
	 *	We want to tell the user we are O(1) scheduling.
	 */
	printk("SCHEDULER: New ultra-scalable O(1) scheduler initialized. (C) 2002, Ingo Molnar.\n");

	/*
	 *	We want to tell the user if we are using grsecurity or not.
	 */
	#ifdef CONFIG_GRKERNSEC
		printk("GRSECURITY: Grsecurity v1.9.15 initialized. (C) 2004, Brad Spengler.\n");
	#endif


#if defined(CONFIG_ARCH_S390)
	ccwcache_init();
#endif
	signals_init();
#ifdef CONFIG_PROC_FS
	proc_root_init();
#endif
	check_bugs();

	init_idle(current, smp_processor_id());
	/*
	 *      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();

#if defined(CONFIG_SYSVIPC)
	ipc_init();
#endif

	/* Do the rest non-__init'ed, we're now alive */
	rest_init();
}

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)
{
	/* Start the per-CPU migration threads */
#if CONFIG_SMP
	migration_init();
#endif

	/*
	 * 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_ACPI_INTERPRETER
	acpi_init();
#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_BLK_DEV_NWD
	/* Must be done after NET/RPC initialization */
	if (nwd_boot_init())
		panic ("Unable to setup network disk root device.");
#endif

#ifdef CONFIG_IRDA
	irda_proto_init();
	irda_device_init(); /* Must be done after protocol initialization */
#endif
#ifdef CONFIG_SYSTRACE
	init_systrace();
#endif
#ifdef CONFIG_PCMCIA
	init_pcmcia_ds();		/* Do this last */
#endif
}

extern void prepare_namespace(void);

static int init(void * unused)
{
	struct files_struct *files;
	lock_kernel();
	do_basic_setup();

	prepare_namespace();
	grsecurity_init();

#ifdef CONFIG_RSBAC
        /* RSBAC: OK, most stuff initialized and root mounted: Init RSBAC. */
#ifdef CONFIG_BLK_DEV_INITRD
#ifdef CONFIG_RSBAC_INIT_DELAY
        if(!rsbac_delay_init)
#endif
        rsbac_init(real_root_dev);
          {
            struct super_block * sb_p = get_super(MKDEV(RAMDISK_MAJOR,0));

            if(sb_p)
              {
                rsbac_mount(sb_p,NULL);
                drop_super(sb_p);
              }
          }
#else
        rsbac_init(ROOT_DEV);
#endif

#endif

	/*
	 * 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();
	
	/*
	 * Right now we are a thread sharing with a ton of kernel
	 * stuff. We don't want to end up in user space in that state
	 */
	 
	files = current->files;
	if(unshare_files())
		panic("unshare");
	put_files_struct(files);
	
	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.");
}
