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v4.6
  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
 13#include <linux/export.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/user.h>
 
 
 20#include <linux/interrupt.h>
 21#include <linux/kallsyms.h>
 22#include <linux/init.h>
 
 23#include <linux/elfcore.h>
 24#include <linux/pm.h>
 25#include <linux/tick.h>
 26#include <linux/utsname.h>
 27#include <linux/uaccess.h>
 28#include <linux/random.h>
 29#include <linux/hw_breakpoint.h>
 30#include <linux/leds.h>
 31
 
 
 32#include <asm/processor.h>
 33#include <asm/thread_notify.h>
 34#include <asm/stacktrace.h>
 35#include <asm/system_misc.h>
 36#include <asm/mach/time.h>
 37#include <asm/tls.h>
 38#include <asm/vdso.h>
 39
 40#ifdef CONFIG_CC_STACKPROTECTOR
 41#include <linux/stackprotector.h>
 42unsigned long __stack_chk_guard __read_mostly;
 43EXPORT_SYMBOL(__stack_chk_guard);
 44#endif
 45
 46static const char *processor_modes[] __maybe_unused = {
 47  "USER_26", "FIQ_26" , "IRQ_26" , "SVC_26" , "UK4_26" , "UK5_26" , "UK6_26" , "UK7_26" ,
 48  "UK8_26" , "UK9_26" , "UK10_26", "UK11_26", "UK12_26", "UK13_26", "UK14_26", "UK15_26",
 49  "USER_32", "FIQ_32" , "IRQ_32" , "SVC_32" , "UK4_32" , "UK5_32" , "MON_32" , "ABT_32" ,
 50  "UK8_32" , "UK9_32" , "HYP_32", "UND_32" , "UK12_32", "UK13_32", "UK14_32", "SYS_32"
 51};
 52
 53static const char *isa_modes[] __maybe_unused = {
 54  "ARM" , "Thumb" , "Jazelle", "ThumbEE"
 55};
 56
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 57/*
 58 * This is our default idle handler.
 
 
 
 
 59 */
 
 60
 61void (*arm_pm_idle)(void);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 62
 63/*
 64 * Called from the core idle loop.
 65 */
 
 
 
 
 
 66
 67void arch_cpu_idle(void)
 
 
 
 
 
 
 68{
 69	if (arm_pm_idle)
 70		arm_pm_idle();
 71	else
 72		cpu_do_idle();
 73	local_irq_enable();
 74}
 75
 76void arch_cpu_idle_prepare(void)
 
 
 
 
 
 
 
 
 
 77{
 78	local_fiq_enable();
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 79}
 80
 81void arch_cpu_idle_enter(void)
 
 
 82{
 83	ledtrig_cpu(CPU_LED_IDLE_START);
 84#ifdef CONFIG_PL310_ERRATA_769419
 85	wmb();
 
 
 
 
 
 
 
 86#endif
 87}
 88
 89void arch_cpu_idle_exit(void)
 
 
 
 
 
 
 
 90{
 91	ledtrig_cpu(CPU_LED_IDLE_END);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 92}
 93
 94void __show_regs(struct pt_regs *regs)
 95{
 96	unsigned long flags;
 97	char buf[64];
 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
114
115	show_regs_print_info(KERN_DEFAULT);
116
 
 
 
 
 
117	print_symbol("PC is at %s\n", instruction_pointer(regs));
118	print_symbol("LR is at %s\n", regs->ARM_lr);
119	printk("pc : [<%08lx>]    lr : [<%08lx>]    psr: %08lx\n"
120	       "sp : %08lx  ip : %08lx  fp : %08lx\n",
121		regs->ARM_pc, regs->ARM_lr, regs->ARM_cpsr,
122		regs->ARM_sp, regs->ARM_ip, regs->ARM_fp);
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);
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
140#ifndef CONFIG_CPU_V7M
141	{
142		const char *segment;
143
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	}
158#else
159	printk("xPSR: %08lx\n", regs->ARM_cpsr);
160#endif
161
162#ifdef CONFIG_CPU_CP15
163	{
164		unsigned int ctrl;
165
166		buf[0] = '\0';
167#ifdef CONFIG_CPU_CP15_MMU
168		{
169			unsigned int transbase;
170			asm("mrc p15, 0, %0, c2, c0\n\t"
171			    : "=r" (transbase));
 
172			snprintf(buf, sizeof(buf), "  Table: %08x  DAC: %08x",
173				transbase, domain);
174		}
175#endif
176		asm("mrc p15, 0, %0, c1, c0\n" : "=r" (ctrl));
177
178		printk("Control: %08x%s\n", ctrl, buf);
179	}
180#endif
181}
182
183void show_regs(struct pt_regs * regs)
184{
 
 
185	__show_regs(regs);
186	dump_stack();
187}
188
189ATOMIC_NOTIFIER_HEAD(thread_notify_head);
190
191EXPORT_SYMBOL_GPL(thread_notify_head);
192
193/*
194 * Free current thread data structures etc..
195 */
196void exit_thread(void)
197{
198	thread_notify(THREAD_NOTIFY_EXIT, current_thread_info());
199}
200
201void flush_thread(void)
202{
203	struct thread_info *thread = current_thread_info();
204	struct task_struct *tsk = current;
205
206	flush_ptrace_hw_breakpoint(tsk);
207
208	memset(thread->used_cp, 0, sizeof(thread->used_cp));
209	memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
210	memset(&thread->fpstate, 0, sizeof(union fp_state));
211
212	flush_tls();
213
214	thread_notify(THREAD_NOTIFY_FLUSH, thread);
215}
216
217void release_thread(struct task_struct *dead_task)
218{
219}
220
221asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
222
223int
224copy_thread(unsigned long clone_flags, unsigned long stack_start,
225	    unsigned long stk_sz, struct task_struct *p)
226{
227	struct thread_info *thread = task_thread_info(p);
228	struct pt_regs *childregs = task_pt_regs(p);
229
230	memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save));
231
232#ifdef CONFIG_CPU_USE_DOMAINS
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();
240#endif
241
242	if (likely(!(p->flags & PF_KTHREAD))) {
243		*childregs = *current_pt_regs();
244		childregs->ARM_r0 = 0;
245		if (stack_start)
246			childregs->ARM_sp = stack_start;
247	} else {
248		memset(childregs, 0, sizeof(struct pt_regs));
249		thread->cpu_context.r4 = stk_sz;
250		thread->cpu_context.r5 = stack_start;
251		childregs->ARM_cpsr = SVC_MODE;
252	}
253	thread->cpu_context.pc = (unsigned long)ret_from_fork;
254	thread->cpu_context.sp = (unsigned long)childregs;
 
255
256	clear_ptrace_hw_breakpoint(p);
257
258	if (clone_flags & CLONE_SETTLS)
259		thread->tp_value[0] = childregs->ARM_r3;
260	thread->tp_value[1] = get_tpuser();
261
262	thread_notify(THREAD_NOTIFY_COPY, thread);
263
264	return 0;
265}
266
267/*
268 * Fill in the task's elfregs structure for a core dump.
269 */
270int 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
276/*
277 * fill in the fpe structure for a core dump...
278 */
279int 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}
289EXPORT_SYMBOL(dump_fpu);
290
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
291unsigned long get_wchan(struct task_struct *p)
292{
293	struct stackframe frame;
294	unsigned long stack_page;
295	int count = 0;
296	if (!p || p == current || p->state == TASK_RUNNING)
297		return 0;
298
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);
303	stack_page = (unsigned long)task_stack_page(p);
304	do {
305		if (frame.sp < stack_page ||
306		    frame.sp >= stack_page + THREAD_SIZE ||
307		    unwind_frame(&frame) < 0)
308			return 0;
309		if (!in_sched_functions(frame.pc))
310			return frame.pc;
311	} while (count ++ < 16);
312	return 0;
313}
314
315unsigned 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}
320
321#ifdef CONFIG_MMU
322#ifdef CONFIG_KUSER_HELPERS
323/*
324 * The vectors page is always readable from user space for the
325 * atomic helpers. Insert it into the gate_vma so that it is visible
326 * through ptrace and /proc/<pid>/mem.
327 */
328static 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,
332};
333
334static int __init gate_vma_init(void)
335{
336	gate_vma.vm_page_prot = PAGE_READONLY_EXEC;
 
 
 
 
337	return 0;
338}
339arch_initcall(gate_vma_init);
340
341struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
342{
343	return &gate_vma;
344}
345
346int 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
351int in_gate_area_no_mm(unsigned long addr)
352{
353	return in_gate_area(NULL, addr);
354}
355#define is_gate_vma(vma)	((vma) == &gate_vma)
356#else
357#define is_gate_vma(vma)	0
358#endif
359
360const char *arch_vma_name(struct vm_area_struct *vma)
361{
362	return is_gate_vma(vma) ? "[vectors]" : NULL;
363}
364
365/* If possible, provide a placement hint at a random offset from the
366 * stack for the sigpage and vdso pages.
367 */
368static 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;
396}
397
398static struct page *signal_page;
399extern struct page *get_signal_page(void);
400
401static const struct vm_special_mapping sigpage_mapping = {
402	.name = "[sigpage]",
403	.pages = &signal_page,
404};
405
406int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
407{
408	struct mm_struct *mm = current->mm;
409	struct vm_area_struct *vma;
410	unsigned long npages;
411	unsigned long addr;
412	unsigned long hint;
413	int ret = 0;
414
415	if (!signal_page)
416		signal_page = get_signal_page();
417	if (!signal_page)
418		return -ENOMEM;
419
420	npages = 1; /* for sigpage */
421	npages += vdso_total_pages;
422
423	down_write(&mm->mmap_sem);
424	hint = sigpage_addr(mm, npages);
425	addr = get_unmapped_area(NULL, hint, npages << PAGE_SHIFT, 0, 0);
426	if (IS_ERR_VALUE(addr)) {
427		ret = addr;
428		goto up_fail;
429	}
430
431	vma = _install_special_mapping(mm, addr, PAGE_SIZE,
432		VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC,
433		&sigpage_mapping);
434
435	if (IS_ERR(vma)) {
436		ret = PTR_ERR(vma);
437		goto up_fail;
438	}
439
440	mm->context.sigpage = addr;
441
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
448 up_fail:
449	up_write(&mm->mmap_sem);
450	return ret;
451}
452#endif
v3.5.6
  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
 13#include <linux/export.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/user.h>
 20#include <linux/delay.h>
 21#include <linux/reboot.h>
 22#include <linux/interrupt.h>
 23#include <linux/kallsyms.h>
 24#include <linux/init.h>
 25#include <linux/cpu.h>
 26#include <linux/elfcore.h>
 27#include <linux/pm.h>
 28#include <linux/tick.h>
 29#include <linux/utsname.h>
 30#include <linux/uaccess.h>
 31#include <linux/random.h>
 32#include <linux/hw_breakpoint.h>
 33#include <linux/cpuidle.h>
 34
 35#include <asm/cacheflush.h>
 36#include <asm/leds.h>
 37#include <asm/processor.h>
 38#include <asm/thread_notify.h>
 39#include <asm/stacktrace.h>
 
 40#include <asm/mach/time.h>
 
 
 41
 42#ifdef CONFIG_CC_STACKPROTECTOR
 43#include <linux/stackprotector.h>
 44unsigned long __stack_chk_guard __read_mostly;
 45EXPORT_SYMBOL(__stack_chk_guard);
 46#endif
 47
 48static const char *processor_modes[] = {
 49  "USER_26", "FIQ_26" , "IRQ_26" , "SVC_26" , "UK4_26" , "UK5_26" , "UK6_26" , "UK7_26" ,
 50  "UK8_26" , "UK9_26" , "UK10_26", "UK11_26", "UK12_26", "UK13_26", "UK14_26", "UK15_26",
 51  "USER_32", "FIQ_32" , "IRQ_32" , "SVC_32" , "UK4_32" , "UK5_32" , "UK6_32" , "ABT_32" ,
 52  "UK8_32" , "UK9_32" , "UK10_32", "UND_32" , "UK12_32", "UK13_32", "UK14_32", "SYS_32"
 53};
 54
 55static const char *isa_modes[] = {
 56  "ARM" , "Thumb" , "Jazelle", "ThumbEE"
 57};
 58
 59extern void setup_mm_for_reboot(void);
 60
 61static volatile int hlt_counter;
 62
 63void disable_hlt(void)
 64{
 65	hlt_counter++;
 66}
 67
 68EXPORT_SYMBOL(disable_hlt);
 69
 70void enable_hlt(void)
 71{
 72	hlt_counter--;
 73}
 74
 75EXPORT_SYMBOL(enable_hlt);
 76
 77static int __init nohlt_setup(char *__unused)
 78{
 79	hlt_counter = 1;
 80	return 1;
 81}
 82
 83static int __init hlt_setup(char *__unused)
 84{
 85	hlt_counter = 0;
 86	return 1;
 87}
 88
 89__setup("nohlt", nohlt_setup);
 90__setup("hlt", hlt_setup);
 91
 92extern void call_with_stack(void (*fn)(void *), void *arg, void *sp);
 93typedef void (*phys_reset_t)(unsigned long);
 94
 95/*
 96 * A temporary stack to use for CPU reset. This is static so that we
 97 * don't clobber it with the identity mapping. When running with this
 98 * stack, any references to the current task *will not work* so you
 99 * should really do as little as possible before jumping to your reset
100 * code.
101 */
102static u64 soft_restart_stack[16];
103
104static void __soft_restart(void *addr)
105{
106	phys_reset_t phys_reset;
107
108	/* Take out a flat memory mapping. */
109	setup_mm_for_reboot();
110
111	/* Clean and invalidate caches */
112	flush_cache_all();
113
114	/* Turn off caching */
115	cpu_proc_fin();
116
117	/* Push out any further dirty data, and ensure cache is empty */
118	flush_cache_all();
119
120	/* Switch to the identity mapping. */
121	phys_reset = (phys_reset_t)(unsigned long)virt_to_phys(cpu_reset);
122	phys_reset((unsigned long)addr);
123
124	/* Should never get here. */
125	BUG();
126}
127
128void soft_restart(unsigned long addr)
129{
130	u64 *stack = soft_restart_stack + ARRAY_SIZE(soft_restart_stack);
131
132	/* Disable interrupts first */
133	local_irq_disable();
134	local_fiq_disable();
135
136	/* Disable the L2 if we're the last man standing. */
137	if (num_online_cpus() == 1)
138		outer_disable();
139
140	/* Change to the new stack and continue with the reset. */
141	call_with_stack(__soft_restart, (void *)addr, (void *)stack);
142
143	/* Should never get here. */
144	BUG();
145}
146
147static void null_restart(char mode, const char *cmd)
148{
149}
150
151/*
152 * Function pointers to optional machine specific functions
153 */
154void (*pm_power_off)(void);
155EXPORT_SYMBOL(pm_power_off);
156
157void (*arm_pm_restart)(char str, const char *cmd) = null_restart;
158EXPORT_SYMBOL_GPL(arm_pm_restart);
159
160/*
161 * This is our default idle handler.
162 */
163
164void (*arm_pm_idle)(void);
165
166static void default_idle(void)
167{
168	if (arm_pm_idle)
169		arm_pm_idle();
170	else
171		cpu_do_idle();
172	local_irq_enable();
173}
174
175void (*pm_idle)(void) = default_idle;
176EXPORT_SYMBOL(pm_idle);
177
178/*
179 * The idle thread, has rather strange semantics for calling pm_idle,
180 * but this is what x86 does and we need to do the same, so that
181 * things like cpuidle get called in the same way.  The only difference
182 * is that we always respect 'hlt_counter' to prevent low power idle.
183 */
184void cpu_idle(void)
185{
186	local_fiq_enable();
187
188	/* endless idle loop with no priority at all */
189	while (1) {
190		tick_nohz_idle_enter();
191		rcu_idle_enter();
192		leds_event(led_idle_start);
193		while (!need_resched()) {
194#ifdef CONFIG_HOTPLUG_CPU
195			if (cpu_is_offline(smp_processor_id()))
196				cpu_die();
197#endif
198
199			/*
200			 * We need to disable interrupts here
201			 * to ensure we don't miss a wakeup call.
202			 */
203			local_irq_disable();
204#ifdef CONFIG_PL310_ERRATA_769419
205			wmb();
206#endif
207			if (hlt_counter) {
208				local_irq_enable();
209				cpu_relax();
210			} else if (!need_resched()) {
211				stop_critical_timings();
212				if (cpuidle_idle_call())
213					pm_idle();
214				start_critical_timings();
215				/*
216				 * pm_idle functions must always
217				 * return with IRQs enabled.
218				 */
219				WARN_ON(irqs_disabled());
220			} else
221				local_irq_enable();
222		}
223		leds_event(led_idle_end);
224		rcu_idle_exit();
225		tick_nohz_idle_exit();
226		schedule_preempt_disabled();
227	}
228}
229
230static char reboot_mode = 'h';
231
232int __init reboot_setup(char *str)
233{
234	reboot_mode = str[0];
235	return 1;
236}
237
238__setup("reboot=", reboot_setup);
239
240void machine_shutdown(void)
241{
242#ifdef CONFIG_SMP
243	smp_send_stop();
244#endif
245}
246
247void machine_halt(void)
248{
249	machine_shutdown();
250	local_irq_disable();
251	while (1);
252}
253
254void machine_power_off(void)
255{
256	machine_shutdown();
257	if (pm_power_off)
258		pm_power_off();
259}
260
261void machine_restart(char *cmd)
262{
263	machine_shutdown();
264
265	arm_pm_restart(reboot_mode, cmd);
266
267	/* Give a grace period for failure to restart of 1s */
268	mdelay(1000);
269
270	/* Whoops - the platform was unable to reboot. Tell the user! */
271	printk("Reboot failed -- System halted\n");
272	local_irq_disable();
273	while (1);
274}
275
276void __show_regs(struct pt_regs *regs)
277{
278	unsigned long flags;
279	char buf[64];
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
280
281	printk("CPU: %d    %s  (%s %.*s)\n",
282		raw_smp_processor_id(), print_tainted(),
283		init_utsname()->release,
284		(int)strcspn(init_utsname()->version, " "),
285		init_utsname()->version);
286	print_symbol("PC is at %s\n", instruction_pointer(regs));
287	print_symbol("LR is at %s\n", regs->ARM_lr);
288	printk("pc : [<%08lx>]    lr : [<%08lx>]    psr: %08lx\n"
289	       "sp : %08lx  ip : %08lx  fp : %08lx\n",
290		regs->ARM_pc, regs->ARM_lr, regs->ARM_cpsr,
291		regs->ARM_sp, regs->ARM_ip, regs->ARM_fp);
292	printk("r10: %08lx  r9 : %08lx  r8 : %08lx\n",
293		regs->ARM_r10, regs->ARM_r9,
294		regs->ARM_r8);
295	printk("r7 : %08lx  r6 : %08lx  r5 : %08lx  r4 : %08lx\n",
296		regs->ARM_r7, regs->ARM_r6,
297		regs->ARM_r5, regs->ARM_r4);
298	printk("r3 : %08lx  r2 : %08lx  r1 : %08lx  r0 : %08lx\n",
299		regs->ARM_r3, regs->ARM_r2,
300		regs->ARM_r1, regs->ARM_r0);
301
302	flags = regs->ARM_cpsr;
303	buf[0] = flags & PSR_N_BIT ? 'N' : 'n';
304	buf[1] = flags & PSR_Z_BIT ? 'Z' : 'z';
305	buf[2] = flags & PSR_C_BIT ? 'C' : 'c';
306	buf[3] = flags & PSR_V_BIT ? 'V' : 'v';
307	buf[4] = '\0';
308
309	printk("Flags: %s  IRQs o%s  FIQs o%s  Mode %s  ISA %s  Segment %s\n",
310		buf, interrupts_enabled(regs) ? "n" : "ff",
311		fast_interrupts_enabled(regs) ? "n" : "ff",
312		processor_modes[processor_mode(regs)],
313		isa_modes[isa_mode(regs)],
314		get_fs() == get_ds() ? "kernel" : "user");
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
315#ifdef CONFIG_CPU_CP15
316	{
317		unsigned int ctrl;
318
319		buf[0] = '\0';
320#ifdef CONFIG_CPU_CP15_MMU
321		{
322			unsigned int transbase, dac;
323			asm("mrc p15, 0, %0, c2, c0\n\t"
324			    "mrc p15, 0, %1, c3, c0\n"
325			    : "=r" (transbase), "=r" (dac));
326			snprintf(buf, sizeof(buf), "  Table: %08x  DAC: %08x",
327			  	transbase, dac);
328		}
329#endif
330		asm("mrc p15, 0, %0, c1, c0\n" : "=r" (ctrl));
331
332		printk("Control: %08x%s\n", ctrl, buf);
333	}
334#endif
335}
336
337void show_regs(struct pt_regs * regs)
338{
339	printk("\n");
340	printk("Pid: %d, comm: %20s\n", task_pid_nr(current), current->comm);
341	__show_regs(regs);
342	dump_stack();
343}
344
345ATOMIC_NOTIFIER_HEAD(thread_notify_head);
346
347EXPORT_SYMBOL_GPL(thread_notify_head);
348
349/*
350 * Free current thread data structures etc..
351 */
352void exit_thread(void)
353{
354	thread_notify(THREAD_NOTIFY_EXIT, current_thread_info());
355}
356
357void flush_thread(void)
358{
359	struct thread_info *thread = current_thread_info();
360	struct task_struct *tsk = current;
361
362	flush_ptrace_hw_breakpoint(tsk);
363
364	memset(thread->used_cp, 0, sizeof(thread->used_cp));
365	memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
366	memset(&thread->fpstate, 0, sizeof(union fp_state));
367
 
 
368	thread_notify(THREAD_NOTIFY_FLUSH, thread);
369}
370
371void release_thread(struct task_struct *dead_task)
372{
373}
374
375asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
376
377int
378copy_thread(unsigned long clone_flags, unsigned long stack_start,
379	    unsigned long stk_sz, struct task_struct *p, struct pt_regs *regs)
380{
381	struct thread_info *thread = task_thread_info(p);
382	struct pt_regs *childregs = task_pt_regs(p);
383
384	*childregs = *regs;
385	childregs->ARM_r0 = 0;
386	childregs->ARM_sp = stack_start;
 
 
 
 
 
 
 
 
387
388	memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save));
 
 
 
 
 
 
 
 
 
 
 
389	thread->cpu_context.sp = (unsigned long)childregs;
390	thread->cpu_context.pc = (unsigned long)ret_from_fork;
391
392	clear_ptrace_hw_breakpoint(p);
393
394	if (clone_flags & CLONE_SETTLS)
395		thread->tp_value = regs->ARM_r3;
 
396
397	thread_notify(THREAD_NOTIFY_COPY, thread);
398
399	return 0;
400}
401
402/*
403 * Fill in the task's elfregs structure for a core dump.
404 */
405int dump_task_regs(struct task_struct *t, elf_gregset_t *elfregs)
406{
407	elf_core_copy_regs(elfregs, task_pt_regs(t));
408	return 1;
409}
410
411/*
412 * fill in the fpe structure for a core dump...
413 */
414int dump_fpu (struct pt_regs *regs, struct user_fp *fp)
415{
416	struct thread_info *thread = current_thread_info();
417	int used_math = thread->used_cp[1] | thread->used_cp[2];
418
419	if (used_math)
420		memcpy(fp, &thread->fpstate.soft, sizeof (*fp));
421
422	return used_math != 0;
423}
424EXPORT_SYMBOL(dump_fpu);
425
426/*
427 * Shuffle the argument into the correct register before calling the
428 * thread function.  r4 is the thread argument, r5 is the pointer to
429 * the thread function, and r6 points to the exit function.
430 */
431extern void kernel_thread_helper(void);
432asm(	".pushsection .text\n"
433"	.align\n"
434"	.type	kernel_thread_helper, #function\n"
435"kernel_thread_helper:\n"
436#ifdef CONFIG_TRACE_IRQFLAGS
437"	bl	trace_hardirqs_on\n"
438#endif
439"	msr	cpsr_c, r7\n"
440"	mov	r0, r4\n"
441"	mov	lr, r6\n"
442"	mov	pc, r5\n"
443"	.size	kernel_thread_helper, . - kernel_thread_helper\n"
444"	.popsection");
445
446#ifdef CONFIG_ARM_UNWIND
447extern void kernel_thread_exit(long code);
448asm(	".pushsection .text\n"
449"	.align\n"
450"	.type	kernel_thread_exit, #function\n"
451"kernel_thread_exit:\n"
452"	.fnstart\n"
453"	.cantunwind\n"
454"	bl	do_exit\n"
455"	nop\n"
456"	.fnend\n"
457"	.size	kernel_thread_exit, . - kernel_thread_exit\n"
458"	.popsection");
459#else
460#define kernel_thread_exit	do_exit
461#endif
462
463/*
464 * Create a kernel thread.
465 */
466pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
467{
468	struct pt_regs regs;
469
470	memset(&regs, 0, sizeof(regs));
471
472	regs.ARM_r4 = (unsigned long)arg;
473	regs.ARM_r5 = (unsigned long)fn;
474	regs.ARM_r6 = (unsigned long)kernel_thread_exit;
475	regs.ARM_r7 = SVC_MODE | PSR_ENDSTATE | PSR_ISETSTATE;
476	regs.ARM_pc = (unsigned long)kernel_thread_helper;
477	regs.ARM_cpsr = regs.ARM_r7 | PSR_I_BIT;
478
479	return do_fork(flags|CLONE_VM|CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);
480}
481EXPORT_SYMBOL(kernel_thread);
482
483unsigned long get_wchan(struct task_struct *p)
484{
485	struct stackframe frame;
 
486	int count = 0;
487	if (!p || p == current || p->state == TASK_RUNNING)
488		return 0;
489
490	frame.fp = thread_saved_fp(p);
491	frame.sp = thread_saved_sp(p);
492	frame.lr = 0;			/* recovered from the stack */
493	frame.pc = thread_saved_pc(p);
 
494	do {
495		int ret = unwind_frame(&frame);
496		if (ret < 0)
 
497			return 0;
498		if (!in_sched_functions(frame.pc))
499			return frame.pc;
500	} while (count ++ < 16);
501	return 0;
502}
503
504unsigned long arch_randomize_brk(struct mm_struct *mm)
505{
506	unsigned long range_end = mm->brk + 0x02000000;
507	return randomize_range(mm->brk, range_end, 0) ? : mm->brk;
508}
509
510#ifdef CONFIG_MMU
 
511/*
512 * The vectors page is always readable from user space for the
513 * atomic helpers and the signal restart code. Insert it into the
514 * gate_vma so that it is visible through ptrace and /proc/<pid>/mem.
515 */
516static struct vm_area_struct gate_vma;
 
 
 
 
517
518static int __init gate_vma_init(void)
519{
520	gate_vma.vm_start	= 0xffff0000;
521	gate_vma.vm_end		= 0xffff0000 + PAGE_SIZE;
522	gate_vma.vm_page_prot	= PAGE_READONLY_EXEC;
523	gate_vma.vm_flags	= VM_READ | VM_EXEC |
524				  VM_MAYREAD | VM_MAYEXEC;
525	return 0;
526}
527arch_initcall(gate_vma_init);
528
529struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
530{
531	return &gate_vma;
532}
533
534int in_gate_area(struct mm_struct *mm, unsigned long addr)
535{
536	return (addr >= gate_vma.vm_start) && (addr < gate_vma.vm_end);
537}
538
539int in_gate_area_no_mm(unsigned long addr)
540{
541	return in_gate_area(NULL, addr);
542}
 
 
 
 
543
544const char *arch_vma_name(struct vm_area_struct *vma)
545{
546	return (vma == &gate_vma) ? "[vectors]" : NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
547}
548#endif