[people/ms/linux.git] / arch / arm / kernel / process.c

/*
 *  linux/arch/arm/kernel/process.c
 *
 *  Copyright (C) 1996-2000 Russell King - Converted to ARM.
 *  Original Copyright (C) 1995  Linus Torvalds
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#include <stdarg.h>

#include <linux/module.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <linux/user.h>
#include <linux/a.out.h>
#include <linux/delay.h>
#include <linux/reboot.h>
#include <linux/interrupt.h>
#include <linux/kallsyms.h>
#include <linux/init.h>
#include <linux/cpu.h>
#include <linux/elfcore.h>
#include <linux/pm.h>

#include <asm/leds.h>
#include <asm/processor.h>
#include <asm/system.h>
#include <asm/thread_notify.h>
#include <asm/uaccess.h>
#include <asm/mach/time.h>

extern const char *processor_modes[];
extern void setup_mm_for_reboot(char mode);

static volatile int hlt_counter;

#include <asm/arch/system.h>

void disable_hlt(void)
{
	hlt_counter++;
}

EXPORT_SYMBOL(disable_hlt);

void enable_hlt(void)
{
	hlt_counter--;
}

EXPORT_SYMBOL(enable_hlt);

static int __init nohlt_setup(char *__unused)
{
	hlt_counter = 1;
	return 1;
}

static int __init hlt_setup(char *__unused)
{
	hlt_counter = 0;
	return 1;
}

__setup("nohlt", nohlt_setup);
__setup("hlt", hlt_setup);

void arm_machine_restart(char mode)
{
	/*
	 * Clean and disable cache, and turn off interrupts
	 */
	cpu_proc_fin();

	/*
	 * Tell the mm system that we are going to reboot -
	 * we may need it to insert some 1:1 mappings so that
	 * soft boot works.
	 */
	setup_mm_for_reboot(mode);

	/*
	 * Now call the architecture specific reboot code.
	 */
	arch_reset(mode);

	/*
	 * Whoops - the architecture was unable to reboot.
	 * Tell the user!
	 */
	mdelay(1000);
	printk("Reboot failed -- System halted\n");
	while (1);
}

/*
 * Function pointers to optional machine specific functions
 */
void (*pm_idle)(void);
EXPORT_SYMBOL(pm_idle);

void (*pm_power_off)(void);
EXPORT_SYMBOL(pm_power_off);

void (*arm_pm_restart)(char str) = arm_machine_restart;
EXPORT_SYMBOL_GPL(arm_pm_restart);


/*
 * This is our default idle handler.  We need to disable
 * interrupts here to ensure we don't miss a wakeup call.
 */
static void default_idle(void)
{
	if (hlt_counter)
		cpu_relax();
	else {
		local_irq_disable();
		if (!need_resched()) {
			timer_dyn_reprogram();
			arch_idle();
		}
		local_irq_enable();
	}
}

/*
 * The idle thread.  We try to conserve power, while trying to keep
 * overall latency low.  The architecture specific idle is passed
 * a value to indicate the level of "idleness" of the system.
 */
void cpu_idle(void)
{
	local_fiq_enable();

	/* endless idle loop with no priority at all */
	while (1) {
		void (*idle)(void) = pm_idle;

#ifdef CONFIG_HOTPLUG_CPU
		if (cpu_is_offline(smp_processor_id())) {
			leds_event(led_idle_start);
			cpu_die();
		}
#endif

		if (!idle)
			idle = default_idle;
		leds_event(led_idle_start);
		while (!need_resched())
			idle();
		leds_event(led_idle_end);
		preempt_enable_no_resched();
		schedule();
		preempt_disable();
	}
}

static char reboot_mode = 'h';

int __init reboot_setup(char *str)
{
	reboot_mode = str[0];
	return 1;
}

__setup("reboot=", reboot_setup);

void machine_halt(void)
{
}


void machine_power_off(void)
{
	if (pm_power_off)
		pm_power_off();
}

void machine_restart(char * __unused)
{
	arm_pm_restart(reboot_mode);
}

void __show_regs(struct pt_regs *regs)
{
	unsigned long flags = condition_codes(regs);

	printk("CPU: %d\n", smp_processor_id());
	print_symbol("PC is at %s\n", instruction_pointer(regs));
	print_symbol("LR is at %s\n", regs->ARM_lr);
	printk("pc : [<%08lx>]    lr : [<%08lx>]    %s\n"
	       "sp : %08lx  ip : %08lx  fp : %08lx\n",
		instruction_pointer(regs),
		regs->ARM_lr, print_tainted(), regs->ARM_sp,
		regs->ARM_ip, regs->ARM_fp);
	printk("r10: %08lx  r9 : %08lx  r8 : %08lx\n",
		regs->ARM_r10, regs->ARM_r9,
		regs->ARM_r8);
	printk("r7 : %08lx  r6 : %08lx  r5 : %08lx  r4 : %08lx\n",
		regs->ARM_r7, regs->ARM_r6,
		regs->ARM_r5, regs->ARM_r4);
	printk("r3 : %08lx  r2 : %08lx  r1 : %08lx  r0 : %08lx\n",
		regs->ARM_r3, regs->ARM_r2,
		regs->ARM_r1, regs->ARM_r0);
	printk("Flags: %c%c%c%c",
		flags & PSR_N_BIT ? 'N' : 'n',
		flags & PSR_Z_BIT ? 'Z' : 'z',
		flags & PSR_C_BIT ? 'C' : 'c',
		flags & PSR_V_BIT ? 'V' : 'v');
	printk("  IRQs o%s  FIQs o%s  Mode %s%s  Segment %s\n",
		interrupts_enabled(regs) ? "n" : "ff",
		fast_interrupts_enabled(regs) ? "n" : "ff",
		processor_modes[processor_mode(regs)],
		thumb_mode(regs) ? " (T)" : "",
		get_fs() == get_ds() ? "kernel" : "user");
	{
		unsigned int ctrl, transbase, dac;
		  __asm__ (
		"	mrc p15, 0, %0, c1, c0\n"
		"	mrc p15, 0, %1, c2, c0\n"
		"	mrc p15, 0, %2, c3, c0\n"
		: "=r" (ctrl), "=r" (transbase), "=r" (dac));
		printk("Control: %04X  Table: %08X  DAC: %08X\n",
		  	ctrl, transbase, dac);
	}
}

void show_regs(struct pt_regs * regs)
{
	printk("\n");
	printk("Pid: %d, comm: %20s\n", current->pid, current->comm);
	__show_regs(regs);
	__backtrace();
}

void show_fpregs(struct user_fp *regs)
{
	int i;

	for (i = 0; i < 8; i++) {
		unsigned long *p;
		char type;

		p = (unsigned long *)(regs->fpregs + i);

		switch (regs->ftype[i]) {
			case 1: type = 'f'; break;
			case 2: type = 'd'; break;
			case 3: type = 'e'; break;
			default: type = '?'; break;
		}
		if (regs->init_flag)
			type = '?';

		printk("  f%d(%c): %08lx %08lx %08lx%c",
			i, type, p[0], p[1], p[2], i & 1 ? '\n' : ' ');
	}
			

	printk("FPSR: %08lx FPCR: %08lx\n",
		(unsigned long)regs->fpsr,
		(unsigned long)regs->fpcr);
}

/*
 * Task structure and kernel stack allocation.
 */
struct thread_info_list {
	unsigned long *head;
	unsigned int nr;
};

static DEFINE_PER_CPU(struct thread_info_list, thread_info_list) = { NULL, 0 };

#define EXTRA_TASK_STRUCT	4

struct thread_info *alloc_thread_info(struct task_struct *task)
{
	struct thread_info *thread = NULL;

	if (EXTRA_TASK_STRUCT) {
		struct thread_info_list *th = &get_cpu_var(thread_info_list);
		unsigned long *p = th->head;

		if (p) {
			th->head = (unsigned long *)p[0];
			th->nr -= 1;
		}
		put_cpu_var(thread_info_list);

		thread = (struct thread_info *)p;
	}

	if (!thread)
		thread = (struct thread_info *)
			   __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);

#ifdef CONFIG_DEBUG_STACK_USAGE
	/*
	 * The stack must be cleared if you want SYSRQ-T to
	 * give sensible stack usage information
	 */
	if (thread)
		memzero(thread, THREAD_SIZE);
#endif
	return thread;
}

void free_thread_info(struct thread_info *thread)
{
	if (EXTRA_TASK_STRUCT) {
		struct thread_info_list *th = &get_cpu_var(thread_info_list);
		if (th->nr < EXTRA_TASK_STRUCT) {
			unsigned long *p = (unsigned long *)thread;
			p[0] = (unsigned long)th->head;
			th->head = p;
			th->nr += 1;
			put_cpu_var(thread_info_list);
			return;
		}
		put_cpu_var(thread_info_list);
	}
	free_pages((unsigned long)thread, THREAD_SIZE_ORDER);
}

/*
 * Free current thread data structures etc..
 */
void exit_thread(void)
{
}

ATOMIC_NOTIFIER_HEAD(thread_notify_head);

EXPORT_SYMBOL_GPL(thread_notify_head);

void flush_thread(void)
{
	struct thread_info *thread = current_thread_info();
	struct task_struct *tsk = current;

	memset(thread->used_cp, 0, sizeof(thread->used_cp));
	memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
	memset(&thread->fpstate, 0, sizeof(union fp_state));

	thread_notify(THREAD_NOTIFY_FLUSH, thread);
}

void release_thread(struct task_struct *dead_task)
{
	struct thread_info *thread = task_thread_info(dead_task);

	thread_notify(THREAD_NOTIFY_RELEASE, thread);
}

asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");

int
copy_thread(int nr, unsigned long clone_flags, unsigned long stack_start,
	    unsigned long stk_sz, struct task_struct *p, struct pt_regs *regs)
{
	struct thread_info *thread = task_thread_info(p);
	struct pt_regs *childregs = task_pt_regs(p);

	*childregs = *regs;
	childregs->ARM_r0 = 0;
	childregs->ARM_sp = stack_start;

	memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save));
	thread->cpu_context.sp = (unsigned long)childregs;
	thread->cpu_context.pc = (unsigned long)ret_from_fork;

	if (clone_flags & CLONE_SETTLS)
		thread->tp_value = regs->ARM_r3;

	return 0;
}

/*
 * fill in the fpe structure for a core dump...
 */
int dump_fpu (struct pt_regs *regs, struct user_fp *fp)
{
	struct thread_info *thread = current_thread_info();
	int used_math = thread->used_cp[1] | thread->used_cp[2];

	if (used_math)
		memcpy(fp, &thread->fpstate.soft, sizeof (*fp));

	return used_math != 0;
}
EXPORT_SYMBOL(dump_fpu);

/*
 * fill in the user structure for a core dump..
 */
void dump_thread(struct pt_regs * regs, struct user * dump)
{
	struct task_struct *tsk = current;

	dump->magic = CMAGIC;
	dump->start_code = tsk->mm->start_code;
	dump->start_stack = regs->ARM_sp & ~(PAGE_SIZE - 1);

	dump->u_tsize = (tsk->mm->end_code - tsk->mm->start_code) >> PAGE_SHIFT;
	dump->u_dsize = (tsk->mm->brk - tsk->mm->start_data + PAGE_SIZE - 1) >> PAGE_SHIFT;
	dump->u_ssize = 0;

	dump->u_debugreg[0] = tsk->thread.debug.bp[0].address;
	dump->u_debugreg[1] = tsk->thread.debug.bp[1].address;
	dump->u_debugreg[2] = tsk->thread.debug.bp[0].insn.arm;
	dump->u_debugreg[3] = tsk->thread.debug.bp[1].insn.arm;
	dump->u_debugreg[4] = tsk->thread.debug.nsaved;

	if (dump->start_stack < 0x04000000)
		dump->u_ssize = (0x04000000 - dump->start_stack) >> PAGE_SHIFT;

	dump->regs = *regs;
	dump->u_fpvalid = dump_fpu (regs, &dump->u_fp);
}
EXPORT_SYMBOL(dump_thread);

/*
 * Shuffle the argument into the correct register before calling the
 * thread function.  r1 is the thread argument, r2 is the pointer to
 * the thread function, and r3 points to the exit function.
 */
extern void kernel_thread_helper(void);
asm(	".section .text\n"
"	.align\n"
"	.type	kernel_thread_helper, #function\n"
"kernel_thread_helper:\n"
"	mov	r0, r1\n"
"	mov	lr, r3\n"
"	mov	pc, r2\n"
"	.size	kernel_thread_helper, . - kernel_thread_helper\n"
"	.previous");

/*
 * Create a kernel thread.
 */
pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
{
	struct pt_regs regs;

	memset(&regs, 0, sizeof(regs));

	regs.ARM_r1 = (unsigned long)arg;
	regs.ARM_r2 = (unsigned long)fn;
	regs.ARM_r3 = (unsigned long)do_exit;
	regs.ARM_pc = (unsigned long)kernel_thread_helper;
	regs.ARM_cpsr = SVC_MODE;

	return do_fork(flags|CLONE_VM|CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);
}
EXPORT_SYMBOL(kernel_thread);

unsigned long get_wchan(struct task_struct *p)
{
	unsigned long fp, lr;
	unsigned long stack_start, stack_end;
	int count = 0;
	if (!p || p == current || p->state == TASK_RUNNING)
		return 0;

	stack_start = (unsigned long)end_of_stack(p);
	stack_end = (unsigned long)task_stack_page(p) + THREAD_SIZE;

	fp = thread_saved_fp(p);
	do {
		if (fp < stack_start || fp > stack_end)
			return 0;
		lr = pc_pointer (((unsigned long *)fp)[-1]);
		if (!in_sched_functions(lr))
			return lr;
		fp = *(unsigned long *) (fp - 12);
	} while (count ++ < 16);
	return 0;
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/arch/arm/kernel/process.c
	3	*
	4	* Copyright (C) 1996-2000 Russell King - Converted to ARM.
	5	* Original Copyright (C) 1995 Linus Torvalds
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License version 2 as
	9	* published by the Free Software Foundation.
	10	*/
	11	#include <stdarg.h>
	12
1da177e4 LT	13	#include <linux/module.h>
	14	#include <linux/sched.h>
	15	#include <linux/kernel.h>
	16	#include <linux/mm.h>
	17	#include <linux/stddef.h>
	18	#include <linux/unistd.h>
	19	#include <linux/ptrace.h>
	20	#include <linux/slab.h>
	21	#include <linux/user.h>
	22	#include <linux/a.out.h>
	23	#include <linux/delay.h>
	24	#include <linux/reboot.h>
	25	#include <linux/interrupt.h>
	26	#include <linux/kallsyms.h>
	27	#include <linux/init.h>
a054a811	28	#include <linux/cpu.h>
84dff1a7	29	#include <linux/elfcore.h>
74617fb6	30	#include <linux/pm.h>
1da177e4	31
1da177e4 LT	32	#include <asm/leds.h>
1da177e4 LT	33	#include <asm/processor.h>
78ff18a4	34	#include <asm/system.h>
d6551e88	35	#include <asm/thread_notify.h>
1da177e4	36	#include <asm/uaccess.h>
2ea83398	37	#include <asm/mach/time.h>
1da177e4 LT	38
	39	extern const char *processor_modes[];
	40	extern void setup_mm_for_reboot(char mode);
	41
	42	static volatile int hlt_counter;
	43
	44	#include <asm/arch/system.h>
	45
	46	void disable_hlt(void)
	47	{
	48	hlt_counter++;
	49	}
	50
	51	EXPORT_SYMBOL(disable_hlt);
	52
	53	void enable_hlt(void)
	54	{
	55	hlt_counter--;
	56	}
	57
	58	EXPORT_SYMBOL(enable_hlt);
	59
	60	static int __init nohlt_setup(char *__unused)
	61	{
	62	hlt_counter = 1;
	63	return 1;
	64	}
	65
	66	static int __init hlt_setup(char *__unused)
	67	{
	68	hlt_counter = 0;
	69	return 1;
	70	}
	71
	72	__setup("nohlt", nohlt_setup);
	73	__setup("hlt", hlt_setup);
	74
74617fb6 RP	75	void arm_machine_restart(char mode)
	76	{
	77	/*
	78	* Clean and disable cache, and turn off interrupts
	79	*/
	80	cpu_proc_fin();
	81
	82	/*
	83	* Tell the mm system that we are going to reboot -
	84	* we may need it to insert some 1:1 mappings so that
	85	* soft boot works.
	86	*/
	87	setup_mm_for_reboot(mode);
	88
	89	/*
	90	* Now call the architecture specific reboot code.
	91	*/
	92	arch_reset(mode);
	93
	94	/*
	95	* Whoops - the architecture was unable to reboot.
	96	* Tell the user!
	97	*/
	98	mdelay(1000);
	99	printk("Reboot failed -- System halted\n");
	100	while (1);
	101	}
	102
1da177e4	103	/*
74617fb6	104	* Function pointers to optional machine specific functions
1da177e4 LT	105	*/
	106	void (*pm_idle)(void);
	107	EXPORT_SYMBOL(pm_idle);
	108
	109	void (*pm_power_off)(void);
	110	EXPORT_SYMBOL(pm_power_off);
	111
74617fb6 RP	112	void (*arm_pm_restart)(char str) = arm_machine_restart;
	113	EXPORT_SYMBOL_GPL(arm_pm_restart);
	114
	115
1da177e4 LT	116	/*
	117	* This is our default idle handler. We need to disable
	118	* interrupts here to ensure we don't miss a wakeup call.
	119	*/
84dff1a7	120	static void default_idle(void)
1da177e4	121	{
64c7c8f8 NP	122	if (hlt_counter)
	123	cpu_relax();
	124	else {
	125	local_irq_disable();
	126	if (!need_resched()) {
	127	timer_dyn_reprogram();
	128	arch_idle();
	129	}
	130	local_irq_enable();
2ea83398	131	}
1da177e4 LT	132	}
	133
	134	/*
	135	* The idle thread. We try to conserve power, while trying to keep
	136	* overall latency low. The architecture specific idle is passed
	137	* a value to indicate the level of "idleness" of the system.
	138	*/
	139	void cpu_idle(void)
	140	{
	141	local_fiq_enable();
	142
	143	/* endless idle loop with no priority at all */
	144	while (1) {
	145	void (*idle)(void) = pm_idle;
a054a811 RK	146
	147	#ifdef CONFIG_HOTPLUG_CPU
	148	if (cpu_is_offline(smp_processor_id())) {
	149	leds_event(led_idle_start);
	150	cpu_die();
	151	}
	152	#endif
	153
1da177e4 LT	154	if (!idle)
1da177e4 LT	155	idle = default_idle;
1da177e4 LT	156	leds_event(led_idle_start);
	157	while (!need_resched())
	158	idle();
	159	leds_event(led_idle_end);
5bfb5d69	160	preempt_enable_no_resched();
1da177e4	161	schedule();
5bfb5d69	162	preempt_disable();
1da177e4 LT	163	}
	164	}
	165
	166	static char reboot_mode = 'h';
	167
	168	int __init reboot_setup(char *str)
	169	{
	170	reboot_mode = str[0];
	171	return 1;
	172	}
	173
	174	__setup("reboot=", reboot_setup);
	175
	176	void machine_halt(void)
	177	{
	178	}
	179
1da177e4 LT	180
	181	void machine_power_off(void)
	182	{
	183	if (pm_power_off)
	184	pm_power_off();
	185	}
	186
1da177e4 LT	187	void machine_restart(char * __unused)
1da177e4 LT	188	{
74617fb6	189	arm_pm_restart(reboot_mode);
1da177e4 LT	190	}
1da177e4 LT	191
652a12ef	192	void __show_regs(struct pt_regs *regs)
1da177e4	193	{
652a12ef	194	unsigned long flags = condition_codes(regs);
1da177e4	195
652a12ef	196	printk("CPU: %d\n", smp_processor_id());
1da177e4 LT	197	print_symbol("PC is at %s\n", instruction_pointer(regs));
	198	print_symbol("LR is at %s\n", regs->ARM_lr);
	199	printk("pc : [<%08lx>] lr : [<%08lx>] %s\n"
	200	"sp : %08lx ip : %08lx fp : %08lx\n",
	201	instruction_pointer(regs),
	202	regs->ARM_lr, print_tainted(), regs->ARM_sp,
	203	regs->ARM_ip, regs->ARM_fp);
	204	printk("r10: %08lx r9 : %08lx r8 : %08lx\n",
	205	regs->ARM_r10, regs->ARM_r9,
	206	regs->ARM_r8);
	207	printk("r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n",
	208	regs->ARM_r7, regs->ARM_r6,
	209	regs->ARM_r5, regs->ARM_r4);
	210	printk("r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n",
	211	regs->ARM_r3, regs->ARM_r2,
	212	regs->ARM_r1, regs->ARM_r0);
	213	printk("Flags: %c%c%c%c",
	214	flags & PSR_N_BIT ? 'N' : 'n',
	215	flags & PSR_Z_BIT ? 'Z' : 'z',
	216	flags & PSR_C_BIT ? 'C' : 'c',
	217	flags & PSR_V_BIT ? 'V' : 'v');
	218	printk(" IRQs o%s FIQs o%s Mode %s%s Segment %s\n",
	219	interrupts_enabled(regs) ? "n" : "ff",
	220	fast_interrupts_enabled(regs) ? "n" : "ff",
	221	processor_modes[processor_mode(regs)],
	222	thumb_mode(regs) ? " (T)" : "",
	223	get_fs() == get_ds() ? "kernel" : "user");
	224	{
	225	unsigned int ctrl, transbase, dac;
	226	__asm__ (
	227	" mrc p15, 0, %0, c1, c0\n"
	228	" mrc p15, 0, %1, c2, c0\n"
	229	" mrc p15, 0, %2, c3, c0\n"
	230	: "=r" (ctrl), "=r" (transbase), "=r" (dac));
	231	printk("Control: %04X Table: %08X DAC: %08X\n",
	232	ctrl, transbase, dac);
	233	}
	234	}
	235
652a12ef RK	236	void show_regs(struct pt_regs * regs)
	237	{
	238	printk("\n");
	239	printk("Pid: %d, comm: %20s\n", current->pid, current->comm);
	240	__show_regs(regs);
	241	__backtrace();
	242	}
	243
1da177e4 LT	244	void show_fpregs(struct user_fp *regs)
	245	{
	246	int i;
	247
	248	for (i = 0; i < 8; i++) {
	249	unsigned long *p;
	250	char type;
	251
	252	p = (unsigned long *)(regs->fpregs + i);
	253
	254	switch (regs->ftype[i]) {
	255	case 1: type = 'f'; break;
	256	case 2: type = 'd'; break;
	257	case 3: type = 'e'; break;
	258	default: type = '?'; break;
	259	}
	260	if (regs->init_flag)
	261	type = '?';
	262
	263	printk(" f%d(%c): %08lx %08lx %08lx%c",
	264	i, type, p[0], p[1], p[2], i & 1 ? '\n' : ' ');
	265	}
	266
	267
	268	printk("FPSR: %08lx FPCR: %08lx\n",
	269	(unsigned long)regs->fpsr,
	270	(unsigned long)regs->fpcr);
	271	}
	272
	273	/*
	274	* Task structure and kernel stack allocation.
	275	*/
1929ab8c RK	276	struct thread_info_list {
	277	unsigned long *head;
	278	unsigned int nr;
	279	};
	280
	281	static DEFINE_PER_CPU(struct thread_info_list, thread_info_list) = { NULL, 0 };
1da177e4 LT	282
1da177e4 LT	283	#define EXTRA_TASK_STRUCT 4
1da177e4 LT	284
	285	struct thread_info alloc_thread_info(struct task_struct task)
	286	{
	287	struct thread_info *thread = NULL;
	288
	289	if (EXTRA_TASK_STRUCT) {
1929ab8c RK	290	struct thread_info_list *th = &get_cpu_var(thread_info_list);
1929ab8c RK	291	unsigned long *p = th->head;
1da177e4 LT	292
1da177e4 LT	293	if (p) {
1929ab8c RK	294	th->head = (unsigned long *)p[0];
1929ab8c RK	295	th->nr -= 1;
1da177e4	296	}
1929ab8c RK	297	put_cpu_var(thread_info_list);
1929ab8c RK	298
1da177e4 LT	299	thread = (struct thread_info *)p;
	300	}
	301
	302	if (!thread)
4f7a1812 RK	303	thread = (struct thread_info *)
4f7a1812 RK	304	__get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
1da177e4	305
4f7a1812	306	#ifdef CONFIG_DEBUG_STACK_USAGE
1da177e4 LT	307	/*
	308	* The stack must be cleared if you want SYSRQ-T to
	309	* give sensible stack usage information
	310	*/
4f7a1812 RK	311	if (thread)
4f7a1812 RK	312	memzero(thread, THREAD_SIZE);
1da177e4 LT	313	#endif
	314	return thread;
	315	}
	316
	317	void free_thread_info(struct thread_info *thread)
	318	{
1929ab8c RK	319	if (EXTRA_TASK_STRUCT) {
	320	struct thread_info_list *th = &get_cpu_var(thread_info_list);
	321	if (th->nr < EXTRA_TASK_STRUCT) {
	322	unsigned long p = (unsigned long )thread;
9d494ccb	323	p[0] = (unsigned long)th->head;
1929ab8c RK	324	th->head = p;
	325	th->nr += 1;
	326	put_cpu_var(thread_info_list);
	327	return;
	328	}
	329	put_cpu_var(thread_info_list);
	330	}
	331	free_pages((unsigned long)thread, THREAD_SIZE_ORDER);
1da177e4 LT	332	}
	333
	334	/*
	335	* Free current thread data structures etc..
	336	*/
	337	void exit_thread(void)
	338	{
	339	}
	340
d6551e88	341	ATOMIC_NOTIFIER_HEAD(thread_notify_head);
1da177e4	342
d6551e88	343	EXPORT_SYMBOL_GPL(thread_notify_head);
1da177e4 LT	344
	345	void flush_thread(void)
	346	{
	347	struct thread_info *thread = current_thread_info();
	348	struct task_struct *tsk = current;
	349
	350	memset(thread->used_cp, 0, sizeof(thread->used_cp));
	351	memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
d6551e88 RK	352	memset(&thread->fpstate, 0, sizeof(union fp_state));
	353
	354	thread_notify(THREAD_NOTIFY_FLUSH, thread);
1da177e4 LT	355	}
	356
	357	void release_thread(struct task_struct *dead_task)
	358	{
d6551e88 RK	359	struct thread_info *thread = task_thread_info(dead_task);
	360
	361	thread_notify(THREAD_NOTIFY_RELEASE, thread);
1da177e4 LT	362	}
	363
	364	asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
	365
	366	int
	367	copy_thread(int nr, unsigned long clone_flags, unsigned long stack_start,
	368	unsigned long stk_sz, struct task_struct p, struct pt_regs regs)
	369	{
815d5ec8 AV	370	struct thread_info *thread = task_thread_info(p);
815d5ec8 AV	371	struct pt_regs *childregs = task_pt_regs(p);
1da177e4	372
1da177e4 LT	373	childregs = regs;
	374	childregs->ARM_r0 = 0;
	375	childregs->ARM_sp = stack_start;
	376
	377	memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save));
	378	thread->cpu_context.sp = (unsigned long)childregs;
	379	thread->cpu_context.pc = (unsigned long)ret_from_fork;
	380
	381	if (clone_flags & CLONE_SETTLS)
	382	thread->tp_value = regs->ARM_r3;
	383
	384	return 0;
	385	}
	386
	387	/*
	388	* fill in the fpe structure for a core dump...
	389	*/
	390	int dump_fpu (struct pt_regs regs, struct user_fp fp)
	391	{
	392	struct thread_info *thread = current_thread_info();
	393	int used_math = thread->used_cp[1] \| thread->used_cp[2];
	394
	395	if (used_math)
	396	memcpy(fp, &thread->fpstate.soft, sizeof (*fp));
	397
	398	return used_math != 0;
	399	}
	400	EXPORT_SYMBOL(dump_fpu);
	401
	402	/*
	403	* fill in the user structure for a core dump..
	404	*/
	405	void dump_thread(struct pt_regs * regs, struct user * dump)
	406	{
	407	struct task_struct *tsk = current;
	408
	409	dump->magic = CMAGIC;
	410	dump->start_code = tsk->mm->start_code;
	411	dump->start_stack = regs->ARM_sp & ~(PAGE_SIZE - 1);
	412
	413	dump->u_tsize = (tsk->mm->end_code - tsk->mm->start_code) >> PAGE_SHIFT;
	414	dump->u_dsize = (tsk->mm->brk - tsk->mm->start_data + PAGE_SIZE - 1) >> PAGE_SHIFT;
	415	dump->u_ssize = 0;
	416
	417	dump->u_debugreg[0] = tsk->thread.debug.bp[0].address;
	418	dump->u_debugreg[1] = tsk->thread.debug.bp[1].address;
	419	dump->u_debugreg[2] = tsk->thread.debug.bp[0].insn.arm;
	420	dump->u_debugreg[3] = tsk->thread.debug.bp[1].insn.arm;
	421	dump->u_debugreg[4] = tsk->thread.debug.nsaved;
	422
	423	if (dump->start_stack < 0x04000000)
	424	dump->u_ssize = (0x04000000 - dump->start_stack) >> PAGE_SHIFT;
	425
	426	dump->regs = *regs;
	427	dump->u_fpvalid = dump_fpu (regs, &dump->u_fp);
	428	}
	429	EXPORT_SYMBOL(dump_thread);
	430
	431	/*
	432	* Shuffle the argument into the correct register before calling the
	433	* thread function. r1 is the thread argument, r2 is the pointer to
	434	* the thread function, and r3 points to the exit function.
	435	*/
	436	extern void kernel_thread_helper(void);
437	asm( ".section .text\n"
438	" .align\n"
439	" .type kernel_thread_helper, #function\n"
440	"kernel_thread_helper:\n"
441	" mov r0, r1\n"
442	" mov lr, r3\n"
443	" mov pc, r2\n"
444	" .size kernel_thread_helper, . - kernel_thread_helper\n"
445	" .previous");
446
447	/*
448	* Create a kernel thread.
449	*/
450	pid_t kernel_thread(int (fn)(void ), void *arg, unsigned long flags)
451	{
452	struct pt_regs regs;
453
454	memset(&regs, 0, sizeof(regs));
455
456	regs.ARM_r1 = (unsigned long)arg;
457	regs.ARM_r2 = (unsigned long)fn;
458	regs.ARM_r3 = (unsigned long)do_exit;
459	regs.ARM_pc = (unsigned long)kernel_thread_helper;
460	regs.ARM_cpsr = SVC_MODE;
461
462	return do_fork(flags\|CLONE_VM\|CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);
463	}
464	EXPORT_SYMBOL(kernel_thread);
465
466	unsigned long get_wchan(struct task_struct *p)
467	{
468	unsigned long fp, lr;
4f7a1812	469	unsigned long stack_start, stack_end;
1da177e4 LT	470	int count = 0;
	471	if (!p \|\| p == current \|\| p->state == TASK_RUNNING)
	472	return 0;
	473
55205823	474	stack_start = (unsigned long)end_of_stack(p);
32d39a93	475	stack_end = (unsigned long)task_stack_page(p) + THREAD_SIZE;
4f7a1812	476
1da177e4 LT	477	fp = thread_saved_fp(p);
1da177e4 LT	478	do {
4f7a1812	479	if (fp < stack_start \|\| fp > stack_end)
1da177e4 LT	480	return 0;
	481	lr = pc_pointer (((unsigned long *)fp)[-1]);
	482	if (!in_sched_functions(lr))
	483	return lr;
	484	fp = (unsigned long ) (fp - 12);
	485	} while (count ++ < 16);
	486	return 0;
	487	}