[deliverable/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/export.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/user.h>
#include <linux/interrupt.h>
#include <linux/kallsyms.h>
#include <linux/init.h>
#include <linux/elfcore.h>
#include <linux/pm.h>
#include <linux/tick.h>
#include <linux/utsname.h>
#include <linux/uaccess.h>
#include <linux/random.h>
#include <linux/hw_breakpoint.h>
#include <linux/leds.h>

#include <asm/processor.h>
#include <asm/thread_notify.h>
#include <asm/stacktrace.h>
#include <asm/system_misc.h>
#include <asm/mach/time.h>
#include <asm/tls.h>
#include <asm/vdso.h>

#ifdef CONFIG_CC_STACKPROTECTOR
#include <linux/stackprotector.h>
unsigned long __stack_chk_guard __read_mostly;
EXPORT_SYMBOL(__stack_chk_guard);
#endif

static const char *processor_modes[] __maybe_unused = {
  "USER_26", "FIQ_26" , "IRQ_26" , "SVC_26" , "UK4_26" , "UK5_26" , "UK6_26" , "UK7_26" ,
  "UK8_26" , "UK9_26" , "UK10_26", "UK11_26", "UK12_26", "UK13_26", "UK14_26", "UK15_26",
  "USER_32", "FIQ_32" , "IRQ_32" , "SVC_32" , "UK4_32" , "UK5_32" , "MON_32" , "ABT_32" ,
  "UK8_32" , "UK9_32" , "HYP_32", "UND_32" , "UK12_32", "UK13_32", "UK14_32", "SYS_32"
};

static const char *isa_modes[] __maybe_unused = {
  "ARM" , "Thumb" , "Jazelle", "ThumbEE"
};

/*
 * This is our default idle handler.
 */

void (*arm_pm_idle)(void);

/*
 * Called from the core idle loop.
 */

void arch_cpu_idle(void)
{
	if (arm_pm_idle)
		arm_pm_idle();
	else
		cpu_do_idle();
	local_irq_enable();
}

void arch_cpu_idle_prepare(void)
{
	local_fiq_enable();
}

void arch_cpu_idle_enter(void)
{
	ledtrig_cpu(CPU_LED_IDLE_START);
#ifdef CONFIG_PL310_ERRATA_769419
	wmb();
#endif
}

void arch_cpu_idle_exit(void)
{
	ledtrig_cpu(CPU_LED_IDLE_END);
}

void __show_regs(struct pt_regs *regs)
{
	unsigned long flags;
	char buf[64];
#ifndef CONFIG_CPU_V7M
	unsigned int domain;
#ifdef CONFIG_CPU_SW_DOMAIN_PAN
	/*
	 * Get the domain register for the parent context. In user
	 * mode, we don't save the DACR, so lets use what it should
	 * be. For other modes, we place it after the pt_regs struct.
	 */
	if (user_mode(regs))
		domain = DACR_UACCESS_ENABLE;
	else
		domain = *(unsigned int *)(regs + 1);
#else
	domain = get_domain();
#endif
#endif

	show_regs_print_info(KERN_DEFAULT);

	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>]    psr: %08lx\n"
	       "sp : %08lx  ip : %08lx  fp : %08lx\n",
		regs->ARM_pc, regs->ARM_lr, regs->ARM_cpsr,
		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);

	flags = regs->ARM_cpsr;
	buf[0] = flags & PSR_N_BIT ? 'N' : 'n';
	buf[1] = flags & PSR_Z_BIT ? 'Z' : 'z';
	buf[2] = flags & PSR_C_BIT ? 'C' : 'c';
	buf[3] = flags & PSR_V_BIT ? 'V' : 'v';
	buf[4] = '\0';

#ifndef CONFIG_CPU_V7M
	{
		const char *segment;

		if ((domain & domain_mask(DOMAIN_USER)) ==
		    domain_val(DOMAIN_USER, DOMAIN_NOACCESS))
			segment = "none";
		else if (get_fs() == get_ds())
			segment = "kernel";
		else
			segment = "user";

		printk("Flags: %s  IRQs o%s  FIQs o%s  Mode %s  ISA %s  Segment %s\n",
			buf, interrupts_enabled(regs) ? "n" : "ff",
			fast_interrupts_enabled(regs) ? "n" : "ff",
			processor_modes[processor_mode(regs)],
			isa_modes[isa_mode(regs)], segment);
	}
#else
	printk("xPSR: %08lx\n", regs->ARM_cpsr);
#endif

#ifdef CONFIG_CPU_CP15
	{
		unsigned int ctrl;

		buf[0] = '\0';
#ifdef CONFIG_CPU_CP15_MMU
		{
			unsigned int transbase;
			asm("mrc p15, 0, %0, c2, c0\n\t"
			    : "=r" (transbase));
			snprintf(buf, sizeof(buf), "  Table: %08x  DAC: %08x",
				transbase, domain);
		}
#endif
		asm("mrc p15, 0, %0, c1, c0\n" : "=r" (ctrl));

		printk("Control: %08x%s\n", ctrl, buf);
	}
#endif
}

void show_regs(struct pt_regs * regs)
{
	__show_regs(regs);
	dump_stack();
}

ATOMIC_NOTIFIER_HEAD(thread_notify_head);

EXPORT_SYMBOL_GPL(thread_notify_head);

/*
 * Free current thread data structures etc..
 */
void exit_thread(void)
{
	thread_notify(THREAD_NOTIFY_EXIT, current_thread_info());
}

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

	flush_ptrace_hw_breakpoint(tsk);

	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));

	flush_tls();

	thread_notify(THREAD_NOTIFY_FLUSH, thread);
}

void release_thread(struct task_struct *dead_task)
{
}

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

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

	memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save));

#ifdef CONFIG_CPU_USE_DOMAINS
	/*
	 * Copy the initial value of the domain access control register
	 * from the current thread: thread->addr_limit will have been
	 * copied from the current thread via setup_thread_stack() in
	 * kernel/fork.c
	 */
	thread->cpu_domain = get_domain();
#endif

	if (likely(!(p->flags & PF_KTHREAD))) {
		*childregs = *current_pt_regs();
		childregs->ARM_r0 = 0;
		if (stack_start)
			childregs->ARM_sp = stack_start;
	} else {
		memset(childregs, 0, sizeof(struct pt_regs));
		thread->cpu_context.r4 = stk_sz;
		thread->cpu_context.r5 = stack_start;
		childregs->ARM_cpsr = SVC_MODE;
	}
	thread->cpu_context.pc = (unsigned long)ret_from_fork;
	thread->cpu_context.sp = (unsigned long)childregs;

	clear_ptrace_hw_breakpoint(p);

	if (clone_flags & CLONE_SETTLS)
		thread->tp_value[0] = childregs->ARM_r3;
	thread->tp_value[1] = get_tpuser();

	thread_notify(THREAD_NOTIFY_COPY, thread);

	return 0;
}

/*
 * Fill in the task's elfregs structure for a core dump.
 */
int dump_task_regs(struct task_struct *t, elf_gregset_t *elfregs)
{
	elf_core_copy_regs(elfregs, task_pt_regs(t));
	return 1;
}

/*
 * 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);

unsigned long get_wchan(struct task_struct *p)
{
	struct stackframe frame;
	unsigned long stack_page;
	int count = 0;
	if (!p || p == current || p->state == TASK_RUNNING)
		return 0;

	frame.fp = thread_saved_fp(p);
	frame.sp = thread_saved_sp(p);
	frame.lr = 0;			/* recovered from the stack */
	frame.pc = thread_saved_pc(p);
	stack_page = (unsigned long)task_stack_page(p);
	do {
		if (frame.sp < stack_page ||
		    frame.sp >= stack_page + THREAD_SIZE ||
		    unwind_frame(&frame) < 0)
			return 0;
		if (!in_sched_functions(frame.pc))
			return frame.pc;
	} while (count ++ < 16);
	return 0;
}

unsigned long arch_randomize_brk(struct mm_struct *mm)
{
	unsigned long range_end = mm->brk + 0x02000000;
	return randomize_range(mm->brk, range_end, 0) ? : mm->brk;
}

#ifdef CONFIG_MMU
#ifdef CONFIG_KUSER_HELPERS
/*
 * The vectors page is always readable from user space for the
 * atomic helpers. Insert it into the gate_vma so that it is visible
 * through ptrace and /proc/<pid>/mem.
 */
static struct vm_area_struct gate_vma = {
	.vm_start	= 0xffff0000,
	.vm_end		= 0xffff0000 + PAGE_SIZE,
	.vm_flags	= VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYEXEC,
};

static int __init gate_vma_init(void)
{
	gate_vma.vm_page_prot = PAGE_READONLY_EXEC;
	return 0;
}
arch_initcall(gate_vma_init);

struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
{
	return &gate_vma;
}

int in_gate_area(struct mm_struct *mm, unsigned long addr)
{
	return (addr >= gate_vma.vm_start) && (addr < gate_vma.vm_end);
}

int in_gate_area_no_mm(unsigned long addr)
{
	return in_gate_area(NULL, addr);
}
#define is_gate_vma(vma)	((vma) == &gate_vma)
#else
#define is_gate_vma(vma)	0
#endif

const char *arch_vma_name(struct vm_area_struct *vma)
{
	return is_gate_vma(vma) ? "[vectors]" : NULL;
}

/* If possible, provide a placement hint at a random offset from the
 * stack for the sigpage and vdso pages.
 */
static unsigned long sigpage_addr(const struct mm_struct *mm,
				  unsigned int npages)
{
	unsigned long offset;
	unsigned long first;
	unsigned long last;
	unsigned long addr;
	unsigned int slots;

	first = PAGE_ALIGN(mm->start_stack);

	last = TASK_SIZE - (npages << PAGE_SHIFT);

	/* No room after stack? */
	if (first > last)
		return 0;

	/* Just enough room? */
	if (first == last)
		return first;

	slots = ((last - first) >> PAGE_SHIFT) + 1;

	offset = get_random_int() % slots;

	addr = first + (offset << PAGE_SHIFT);

	return addr;
}

static struct page *signal_page;
extern struct page *get_signal_page(void);

static const struct vm_special_mapping sigpage_mapping = {
	.name = "[sigpage]",
	.pages = &signal_page,
};

int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
{
	struct mm_struct *mm = current->mm;
	struct vm_area_struct *vma;
	unsigned long npages;
	unsigned long addr;
	unsigned long hint;
	int ret = 0;

	if (!signal_page)
		signal_page = get_signal_page();
	if (!signal_page)
		return -ENOMEM;

	npages = 1; /* for sigpage */
	npages += vdso_total_pages;

	down_write(&mm->mmap_sem);
	hint = sigpage_addr(mm, npages);
	addr = get_unmapped_area(NULL, hint, npages << PAGE_SHIFT, 0, 0);
	if (IS_ERR_VALUE(addr)) {
		ret = addr;
		goto up_fail;
	}

	vma = _install_special_mapping(mm, addr, PAGE_SIZE,
		VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC,
		&sigpage_mapping);

	if (IS_ERR(vma)) {
		ret = PTR_ERR(vma);
		goto up_fail;
	}

	mm->context.sigpage = addr;

	/* Unlike the sigpage, failure to install the vdso is unlikely
	 * to be fatal to the process, so no error check needed
	 * here.
	 */
	arm_install_vdso(mm, addr + PAGE_SIZE);

 up_fail:
	up_write(&mm->mmap_sem);
	return ret;
}
#endif
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
ecea4ab6	13	#include <linux/export.h>
1da177e4 LT	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>
1da177e4	19	#include <linux/user.h>
1da177e4 LT	20	#include <linux/interrupt.h>
	21	#include <linux/kallsyms.h>
	22	#include <linux/init.h>
84dff1a7	23	#include <linux/elfcore.h>
74617fb6	24	#include <linux/pm.h>
9e4559dd	25	#include <linux/tick.h>
154c772e	26	#include <linux/utsname.h>
33fa9b13	27	#include <linux/uaccess.h>
990cb8ac	28	#include <linux/random.h>
864232fa	29	#include <linux/hw_breakpoint.h>
fa8bbb13	30	#include <linux/leds.h>
1da177e4	31
1da177e4	32	#include <asm/processor.h>
d6551e88	33	#include <asm/thread_notify.h>
2d7c11bf	34	#include <asm/stacktrace.h>
779dd959	35	#include <asm/system_misc.h>
2ea83398	36	#include <asm/mach/time.h>
a4780ade	37	#include <asm/tls.h>
045ab94e	38	#include <asm/vdso.h>
1da177e4	39
c743f380 NP	40	#ifdef CONFIG_CC_STACKPROTECTOR
	41	#include <linux/stackprotector.h>
	42	unsigned long __stack_chk_guard __read_mostly;
	43	EXPORT_SYMBOL(__stack_chk_guard);
	44	#endif
	45
e2e55fde	46	static const char *processor_modes[] __maybe_unused = {
ae0a846e RK	47	"USER_26", "FIQ_26" , "IRQ_26" , "SVC_26" , "UK4_26" , "UK5_26" , "UK6_26" , "UK7_26" ,
ae0a846e RK	48	"UK8_26" , "UK9_26" , "UK10_26", "UK11_26", "UK12_26", "UK13_26", "UK14_26", "UK15_26",
f3a04202 SB	49	"USER_32", "FIQ_32" , "IRQ_32" , "SVC_32" , "UK4_32" , "UK5_32" , "MON_32" , "ABT_32" ,
f3a04202 SB	50	"UK8_32" , "UK9_32" , "HYP_32", "UND_32" , "UK12_32", "UK13_32", "UK14_32", "SYS_32"
ae0a846e RK	51	};
ae0a846e RK	52
e2e55fde	53	static const char *isa_modes[] __maybe_unused = {
909d6c6c GD	54	"ARM" , "Thumb" , "Jazelle", "ThumbEE"
	55	};
	56
1da177e4	57	/*
4fa20439	58	* This is our default idle handler.
1da177e4	59	*/
4fa20439 NP	60
	61	void (*arm_pm_idle)(void);
	62
ad68cc7a NP	63	/*
	64	* Called from the core idle loop.
	65	*/
	66
	67	void arch_cpu_idle(void)
1da177e4	68	{
4fa20439 NP	69	if (arm_pm_idle)
	70	arm_pm_idle();
	71	else
ae940913	72	cpu_do_idle();
9ccdac36	73	local_irq_enable();
1da177e4 LT	74	}
1da177e4 LT	75
f7b861b7	76	void arch_cpu_idle_prepare(void)
1da177e4 LT	77	{
1da177e4 LT	78	local_fiq_enable();
f7b861b7	79	}
1da177e4	80
f7b861b7 TG	81	void arch_cpu_idle_enter(void)
	82	{
	83	ledtrig_cpu(CPU_LED_IDLE_START);
	84	#ifdef CONFIG_PL310_ERRATA_769419
	85	wmb();
a054a811	86	#endif
f7b861b7	87	}
a054a811	88
f7b861b7 TG	89	void arch_cpu_idle_exit(void)
	90	{
	91	ledtrig_cpu(CPU_LED_IDLE_END);
	92	}
	93
652a12ef	94	void __show_regs(struct pt_regs *regs)
1da177e4	95	{
154c772e RK	96	unsigned long flags;
154c772e RK	97	char buf[64];
77f1b959 RK	98	#ifndef CONFIG_CPU_V7M
	99	unsigned int domain;
	100	#ifdef CONFIG_CPU_SW_DOMAIN_PAN
	101	/*
	102	* Get the domain register for the parent context. In user
	103	* mode, we don't save the DACR, so lets use what it should
	104	* be. For other modes, we place it after the pt_regs struct.
	105	*/
	106	if (user_mode(regs))
	107	domain = DACR_UACCESS_ENABLE;
	108	else
	109	domain = (unsigned int )(regs + 1);
	110	#else
	111	domain = get_domain();
	112	#endif
	113	#endif
1da177e4	114
a43cb95d TH	115	show_regs_print_info(KERN_DEFAULT);
a43cb95d TH	116
1da177e4 LT	117	print_symbol("PC is at %s\n", instruction_pointer(regs));
1da177e4 LT	118	print_symbol("LR is at %s\n", regs->ARM_lr);
154c772e	119	printk("pc : [<%08lx>] lr : [<%08lx>] psr: %08lx\n"
1da177e4	120	"sp : %08lx ip : %08lx fp : %08lx\n",
154c772e RK	121	regs->ARM_pc, regs->ARM_lr, regs->ARM_cpsr,
154c772e RK	122	regs->ARM_sp, regs->ARM_ip, regs->ARM_fp);
1da177e4 LT	123	printk("r10: %08lx r9 : %08lx r8 : %08lx\n",
	124	regs->ARM_r10, regs->ARM_r9,
	125	regs->ARM_r8);
	126	printk("r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n",
	127	regs->ARM_r7, regs->ARM_r6,
	128	regs->ARM_r5, regs->ARM_r4);
	129	printk("r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n",
	130	regs->ARM_r3, regs->ARM_r2,
	131	regs->ARM_r1, regs->ARM_r0);
154c772e RK	132
	133	flags = regs->ARM_cpsr;
	134	buf[0] = flags & PSR_N_BIT ? 'N' : 'n';
	135	buf[1] = flags & PSR_Z_BIT ? 'Z' : 'z';
	136	buf[2] = flags & PSR_C_BIT ? 'C' : 'c';
	137	buf[3] = flags & PSR_V_BIT ? 'V' : 'v';
	138	buf[4] = '\0';
	139
e2e55fde	140	#ifndef CONFIG_CPU_V7M
a5e090ac	141	{
a5e090ac RK	142	const char *segment;
a5e090ac RK	143
a5e090ac RK	144	if ((domain & domain_mask(DOMAIN_USER)) ==
	145	domain_val(DOMAIN_USER, DOMAIN_NOACCESS))
	146	segment = "none";
	147	else if (get_fs() == get_ds())
	148	segment = "kernel";
	149	else
	150	segment = "user";
	151
	152	printk("Flags: %s IRQs o%s FIQs o%s Mode %s ISA %s Segment %s\n",
	153	buf, interrupts_enabled(regs) ? "n" : "ff",
	154	fast_interrupts_enabled(regs) ? "n" : "ff",
	155	processor_modes[processor_mode(regs)],
	156	isa_modes[isa_mode(regs)], segment);
	157	}
e2e55fde UKK	158	#else
	159	printk("xPSR: %08lx\n", regs->ARM_cpsr);
	160	#endif
	161
154c772e	162	#ifdef CONFIG_CPU_CP15
1da177e4	163	{
f12d0d7c	164	unsigned int ctrl;
154c772e RK	165
154c772e RK	166	buf[0] = '\0';
f12d0d7c	167	#ifdef CONFIG_CPU_CP15_MMU
154c772e	168	{
77f1b959	169	unsigned int transbase;
154c772e	170	asm("mrc p15, 0, %0, c2, c0\n\t"
1eef5d2f	171	: "=r" (transbase));
154c772e	172	snprintf(buf, sizeof(buf), " Table: %08x DAC: %08x",
77f1b959	173	transbase, domain);
154c772e	174	}
f12d0d7c	175	#endif
154c772e RK	176	asm("mrc p15, 0, %0, c1, c0\n" : "=r" (ctrl));
	177
	178	printk("Control: %08x%s\n", ctrl, buf);
	179	}
f12d0d7c	180	#endif
1da177e4 LT	181	}
1da177e4 LT	182
652a12ef RK	183	void show_regs(struct pt_regs * regs)
652a12ef RK	184	{
652a12ef	185	__show_regs(regs);
b380ab4f	186	dump_stack();
652a12ef RK	187	}
652a12ef RK	188
797245f5 RK	189	ATOMIC_NOTIFIER_HEAD(thread_notify_head);
	190
	191	EXPORT_SYMBOL_GPL(thread_notify_head);
	192
1da177e4 LT	193	/*
	194	* Free current thread data structures etc..
	195	*/
	196	void exit_thread(void)
	197	{
797245f5	198	thread_notify(THREAD_NOTIFY_EXIT, current_thread_info());
1da177e4 LT	199	}
1da177e4 LT	200
1da177e4 LT	201	void flush_thread(void)
	202	{
	203	struct thread_info *thread = current_thread_info();
	204	struct task_struct *tsk = current;
	205
864232fa WD	206	flush_ptrace_hw_breakpoint(tsk);
864232fa WD	207
1da177e4 LT	208	memset(thread->used_cp, 0, sizeof(thread->used_cp));
1da177e4 LT	209	memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
d6551e88 RK	210	memset(&thread->fpstate, 0, sizeof(union fp_state));
d6551e88 RK	211
fbfb872f NL	212	flush_tls();
fbfb872f NL	213
d6551e88	214	thread_notify(THREAD_NOTIFY_FLUSH, thread);
1da177e4 LT	215	}
	216
	217	void release_thread(struct task_struct *dead_task)
	218	{
1da177e4 LT	219	}
	220
	221	asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
	222
	223	int
6f2c55b8	224	copy_thread(unsigned long clone_flags, unsigned long stack_start,
afa86fc4	225	unsigned long stk_sz, struct task_struct *p)
1da177e4	226	{
815d5ec8 AV	227	struct thread_info *thread = task_thread_info(p);
815d5ec8 AV	228	struct pt_regs *childregs = task_pt_regs(p);
1da177e4	229
1da177e4	230	memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save));
9e14f828	231
af4cb25d	232	#ifdef CONFIG_CPU_USE_DOMAINS
1eef5d2f RK	233	/*
	234	* Copy the initial value of the domain access control register
	235	* from the current thread: thread->addr_limit will have been
	236	* copied from the current thread via setup_thread_stack() in
	237	* kernel/fork.c
	238	*/
	239	thread->cpu_domain = get_domain();
af4cb25d	240	#endif
1eef5d2f	241
38a61b6b AV	242	if (likely(!(p->flags & PF_KTHREAD))) {
38a61b6b AV	243	childregs = current_pt_regs();
9e14f828	244	childregs->ARM_r0 = 0;
38a61b6b AV	245	if (stack_start)
38a61b6b AV	246	childregs->ARM_sp = stack_start;
9e14f828	247	} else {
9fff2fa0	248	memset(childregs, 0, sizeof(struct pt_regs));
9e14f828 AV	249	thread->cpu_context.r4 = stk_sz;
9e14f828 AV	250	thread->cpu_context.r5 = stack_start;
9e14f828 AV	251	childregs->ARM_cpsr = SVC_MODE;
9e14f828 AV	252	}
9fff2fa0	253	thread->cpu_context.pc = (unsigned long)ret_from_fork;
1da177e4	254	thread->cpu_context.sp = (unsigned long)childregs;
1da177e4	255
864232fa WD	256	clear_ptrace_hw_breakpoint(p);
864232fa WD	257
1da177e4	258	if (clone_flags & CLONE_SETTLS)
a4780ade AH	259	thread->tp_value[0] = childregs->ARM_r3;
a4780ade AH	260	thread->tp_value[1] = get_tpuser();
1da177e4	261
2e82669a CM	262	thread_notify(THREAD_NOTIFY_COPY, thread);
2e82669a CM	263
1da177e4 LT	264	return 0;
	265	}
	266
cde3f860 AB	267	/*
	268	* Fill in the task's elfregs structure for a core dump.
	269	*/
	270	int dump_task_regs(struct task_struct t, elf_gregset_t elfregs)
	271	{
	272	elf_core_copy_regs(elfregs, task_pt_regs(t));
	273	return 1;
	274	}
	275
1da177e4 LT	276	/*
	277	* fill in the fpe structure for a core dump...
	278	*/
	279	int dump_fpu (struct pt_regs regs, struct user_fp fp)
	280	{
	281	struct thread_info *thread = current_thread_info();
	282	int used_math = thread->used_cp[1] \| thread->used_cp[2];
	283
	284	if (used_math)
	285	memcpy(fp, &thread->fpstate.soft, sizeof (*fp));
	286
	287	return used_math != 0;
	288	}
	289	EXPORT_SYMBOL(dump_fpu);
	290
1da177e4 LT	291	unsigned long get_wchan(struct task_struct *p)
1da177e4 LT	292	{
2d7c11bf	293	struct stackframe frame;
1b15ec7a	294	unsigned long stack_page;
1da177e4 LT	295	int count = 0;
	296	if (!p \|\| p == current \|\| p->state == TASK_RUNNING)
	297	return 0;
	298
2d7c11bf CM	299	frame.fp = thread_saved_fp(p);
	300	frame.sp = thread_saved_sp(p);
	301	frame.lr = 0; /* recovered from the stack */
	302	frame.pc = thread_saved_pc(p);
1b15ec7a	303	stack_page = (unsigned long)task_stack_page(p);
1da177e4	304	do {
1b15ec7a KK	305	if (frame.sp < stack_page \|\|
	306	frame.sp >= stack_page + THREAD_SIZE \|\|
	307	unwind_frame(&frame) < 0)
1da177e4	308	return 0;
2d7c11bf CM	309	if (!in_sched_functions(frame.pc))
2d7c11bf CM	310	return frame.pc;
1da177e4 LT	311	} while (count ++ < 16);
	312	return 0;
	313	}
990cb8ac NP	314
	315	unsigned long arch_randomize_brk(struct mm_struct *mm)
	316	{
	317	unsigned long range_end = mm->brk + 0x02000000;
	318	return randomize_range(mm->brk, range_end, 0) ? : mm->brk;
	319	}
ec706dab	320
6cde6d42	321	#ifdef CONFIG_MMU
a5463cd3	322	#ifdef CONFIG_KUSER_HELPERS
ec706dab NP	323	/*
ec706dab NP	324	* The vectors page is always readable from user space for the
48be69a0 RK	325	* atomic helpers. Insert it into the gate_vma so that it is visible
48be69a0 RK	326	* through ptrace and /proc/<pid>/mem.
ec706dab	327	*/
f6604efe RK	328	static struct vm_area_struct gate_vma = {
	329	.vm_start = 0xffff0000,
	330	.vm_end = 0xffff0000 + PAGE_SIZE,
	331	.vm_flags = VM_READ \| VM_EXEC \| VM_MAYREAD \| VM_MAYEXEC,
f6604efe	332	};
ec706dab	333
f9d4861f	334	static int __init gate_vma_init(void)
ec706dab	335	{
f6604efe	336	gate_vma.vm_page_prot = PAGE_READONLY_EXEC;
f9d4861f WD	337	return 0;
	338	}
	339	arch_initcall(gate_vma_init);
	340
	341	struct vm_area_struct get_gate_vma(struct mm_struct mm)
	342	{
	343	return &gate_vma;
	344	}
	345
	346	int in_gate_area(struct mm_struct *mm, unsigned long addr)
	347	{
	348	return (addr >= gate_vma.vm_start) && (addr < gate_vma.vm_end);
	349	}
	350
	351	int in_gate_area_no_mm(unsigned long addr)
	352	{
	353	return in_gate_area(NULL, addr);
ec706dab	354	}
1d0bbf42	355	#define is_gate_vma(vma) ((vma) == &gate_vma)
a5463cd3 RK	356	#else
	357	#define is_gate_vma(vma) 0
	358	#endif
ec706dab NP	359
	360	const char arch_vma_name(struct vm_area_struct vma)
	361	{
02e0409a	362	return is_gate_vma(vma) ? "[vectors]" : NULL;
48be69a0 RK	363	}
48be69a0 RK	364
389522b0	365	/* If possible, provide a placement hint at a random offset from the
ecf99a43	366	* stack for the sigpage and vdso pages.
389522b0 NL	367	*/
	368	static unsigned long sigpage_addr(const struct mm_struct *mm,
	369	unsigned int npages)
	370	{
	371	unsigned long offset;
	372	unsigned long first;
	373	unsigned long last;
	374	unsigned long addr;
	375	unsigned int slots;
	376
	377	first = PAGE_ALIGN(mm->start_stack);
	378
	379	last = TASK_SIZE - (npages << PAGE_SHIFT);
	380
	381	/* No room after stack? */
	382	if (first > last)
	383	return 0;
	384
	385	/* Just enough room? */
	386	if (first == last)
	387	return first;
	388
	389	slots = ((last - first) >> PAGE_SHIFT) + 1;
	390
	391	offset = get_random_int() % slots;
	392
	393	addr = first + (offset << PAGE_SHIFT);
	394
	395	return addr;
48be69a0 RK	396	}
48be69a0 RK	397
e0d40756	398	static struct page *signal_page;
48be69a0 RK	399	extern struct page *get_signal_page(void);
48be69a0 RK	400
02e0409a NL	401	static const struct vm_special_mapping sigpage_mapping = {
	402	.name = "[sigpage]",
	403	.pages = &signal_page,
	404	};
	405
48be69a0 RK	406	int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
	407	{
	408	struct mm_struct *mm = current->mm;
02e0409a	409	struct vm_area_struct *vma;
ecf99a43	410	unsigned long npages;
48be69a0	411	unsigned long addr;
389522b0	412	unsigned long hint;
02e0409a	413	int ret = 0;
48be69a0	414
e0d40756 RK	415	if (!signal_page)
	416	signal_page = get_signal_page();
	417	if (!signal_page)
48be69a0 RK	418	return -ENOMEM;
48be69a0 RK	419
ecf99a43 NL	420	npages = 1; /* for sigpage */
	421	npages += vdso_total_pages;
	422
48be69a0	423	down_write(&mm->mmap_sem);
ecf99a43 NL	424	hint = sigpage_addr(mm, npages);
ecf99a43 NL	425	addr = get_unmapped_area(NULL, hint, npages << PAGE_SHIFT, 0, 0);
48be69a0 RK	426	if (IS_ERR_VALUE(addr)) {
	427	ret = addr;
	428	goto up_fail;
	429	}
	430
02e0409a	431	vma = _install_special_mapping(mm, addr, PAGE_SIZE,
48be69a0	432	VM_READ \| VM_EXEC \| VM_MAYREAD \| VM_MAYWRITE \| VM_MAYEXEC,
02e0409a NL	433	&sigpage_mapping);
	434
	435	if (IS_ERR(vma)) {
	436	ret = PTR_ERR(vma);
	437	goto up_fail;
	438	}
48be69a0	439
02e0409a	440	mm->context.sigpage = addr;
48be69a0	441
ecf99a43 NL	442	/* Unlike the sigpage, failure to install the vdso is unlikely
	443	* to be fatal to the process, so no error check needed
	444	* here.
	445	*/
	446	arm_install_vdso(mm, addr + PAGE_SIZE);
	447
48be69a0 RK	448	up_fail:
	449	up_write(&mm->mmap_sem);
	450	return ret;
ec706dab	451	}
6cde6d42	452	#endif