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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(®s, 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, ®s, 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
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, fs;
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 fs = get_fs();
109 } else {
110 domain = to_svc_pt_regs(regs)->dacr;
111 fs = to_svc_pt_regs(regs)->addr_limit;
112 }
113#else
114 domain = get_domain();
115 fs = get_fs();
116#endif
117#endif
118
119 show_regs_print_info(KERN_DEFAULT);
120
121 print_symbol("PC is at %s\n", instruction_pointer(regs));
122 print_symbol("LR is at %s\n", regs->ARM_lr);
123 printk("pc : [<%08lx>] lr : [<%08lx>] psr: %08lx\n"
124 "sp : %08lx ip : %08lx fp : %08lx\n",
125 regs->ARM_pc, regs->ARM_lr, regs->ARM_cpsr,
126 regs->ARM_sp, regs->ARM_ip, regs->ARM_fp);
127 printk("r10: %08lx r9 : %08lx r8 : %08lx\n",
128 regs->ARM_r10, regs->ARM_r9,
129 regs->ARM_r8);
130 printk("r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n",
131 regs->ARM_r7, regs->ARM_r6,
132 regs->ARM_r5, regs->ARM_r4);
133 printk("r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n",
134 regs->ARM_r3, regs->ARM_r2,
135 regs->ARM_r1, regs->ARM_r0);
136
137 flags = regs->ARM_cpsr;
138 buf[0] = flags & PSR_N_BIT ? 'N' : 'n';
139 buf[1] = flags & PSR_Z_BIT ? 'Z' : 'z';
140 buf[2] = flags & PSR_C_BIT ? 'C' : 'c';
141 buf[3] = flags & PSR_V_BIT ? 'V' : 'v';
142 buf[4] = '\0';
143
144#ifndef CONFIG_CPU_V7M
145 {
146 const char *segment;
147
148 if ((domain & domain_mask(DOMAIN_USER)) ==
149 domain_val(DOMAIN_USER, DOMAIN_NOACCESS))
150 segment = "none";
151 else if (fs == get_ds())
152 segment = "kernel";
153 else
154 segment = "user";
155
156 printk("Flags: %s IRQs o%s FIQs o%s Mode %s ISA %s Segment %s\n",
157 buf, interrupts_enabled(regs) ? "n" : "ff",
158 fast_interrupts_enabled(regs) ? "n" : "ff",
159 processor_modes[processor_mode(regs)],
160 isa_modes[isa_mode(regs)], segment);
161 }
162#else
163 printk("xPSR: %08lx\n", regs->ARM_cpsr);
164#endif
165
166#ifdef CONFIG_CPU_CP15
167 {
168 unsigned int ctrl;
169
170 buf[0] = '\0';
171#ifdef CONFIG_CPU_CP15_MMU
172 {
173 unsigned int transbase;
174 asm("mrc p15, 0, %0, c2, c0\n\t"
175 : "=r" (transbase));
176 snprintf(buf, sizeof(buf), " Table: %08x DAC: %08x",
177 transbase, domain);
178 }
179#endif
180 asm("mrc p15, 0, %0, c1, c0\n" : "=r" (ctrl));
181
182 printk("Control: %08x%s\n", ctrl, buf);
183 }
184#endif
185}
186
187void show_regs(struct pt_regs * regs)
188{
189 __show_regs(regs);
190 dump_stack();
191}
192
193ATOMIC_NOTIFIER_HEAD(thread_notify_head);
194
195EXPORT_SYMBOL_GPL(thread_notify_head);
196
197/*
198 * Free current thread data structures etc..
199 */
200void exit_thread(struct task_struct *tsk)
201{
202 thread_notify(THREAD_NOTIFY_EXIT, task_thread_info(tsk));
203}
204
205void flush_thread(void)
206{
207 struct thread_info *thread = current_thread_info();
208 struct task_struct *tsk = current;
209
210 flush_ptrace_hw_breakpoint(tsk);
211
212 memset(thread->used_cp, 0, sizeof(thread->used_cp));
213 memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
214 memset(&thread->fpstate, 0, sizeof(union fp_state));
215
216 flush_tls();
217
218 thread_notify(THREAD_NOTIFY_FLUSH, thread);
219}
220
221void release_thread(struct task_struct *dead_task)
222{
223}
224
225asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
226
227int
228copy_thread(unsigned long clone_flags, unsigned long stack_start,
229 unsigned long stk_sz, struct task_struct *p)
230{
231 struct thread_info *thread = task_thread_info(p);
232 struct pt_regs *childregs = task_pt_regs(p);
233
234 memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save));
235
236#ifdef CONFIG_CPU_USE_DOMAINS
237 /*
238 * Copy the initial value of the domain access control register
239 * from the current thread: thread->addr_limit will have been
240 * copied from the current thread via setup_thread_stack() in
241 * kernel/fork.c
242 */
243 thread->cpu_domain = get_domain();
244#endif
245
246 if (likely(!(p->flags & PF_KTHREAD))) {
247 *childregs = *current_pt_regs();
248 childregs->ARM_r0 = 0;
249 if (stack_start)
250 childregs->ARM_sp = stack_start;
251 } else {
252 memset(childregs, 0, sizeof(struct pt_regs));
253 thread->cpu_context.r4 = stk_sz;
254 thread->cpu_context.r5 = stack_start;
255 childregs->ARM_cpsr = SVC_MODE;
256 }
257 thread->cpu_context.pc = (unsigned long)ret_from_fork;
258 thread->cpu_context.sp = (unsigned long)childregs;
259
260 clear_ptrace_hw_breakpoint(p);
261
262 if (clone_flags & CLONE_SETTLS)
263 thread->tp_value[0] = childregs->ARM_r3;
264 thread->tp_value[1] = get_tpuser();
265
266 thread_notify(THREAD_NOTIFY_COPY, thread);
267
268 return 0;
269}
270
271/*
272 * Fill in the task's elfregs structure for a core dump.
273 */
274int dump_task_regs(struct task_struct *t, elf_gregset_t *elfregs)
275{
276 elf_core_copy_regs(elfregs, task_pt_regs(t));
277 return 1;
278}
279
280/*
281 * fill in the fpe structure for a core dump...
282 */
283int dump_fpu (struct pt_regs *regs, struct user_fp *fp)
284{
285 struct thread_info *thread = current_thread_info();
286 int used_math = thread->used_cp[1] | thread->used_cp[2];
287
288 if (used_math)
289 memcpy(fp, &thread->fpstate.soft, sizeof (*fp));
290
291 return used_math != 0;
292}
293EXPORT_SYMBOL(dump_fpu);
294
295unsigned long get_wchan(struct task_struct *p)
296{
297 struct stackframe frame;
298 unsigned long stack_page;
299 int count = 0;
300 if (!p || p == current || p->state == TASK_RUNNING)
301 return 0;
302
303 frame.fp = thread_saved_fp(p);
304 frame.sp = thread_saved_sp(p);
305 frame.lr = 0; /* recovered from the stack */
306 frame.pc = thread_saved_pc(p);
307 stack_page = (unsigned long)task_stack_page(p);
308 do {
309 if (frame.sp < stack_page ||
310 frame.sp >= stack_page + THREAD_SIZE ||
311 unwind_frame(&frame) < 0)
312 return 0;
313 if (!in_sched_functions(frame.pc))
314 return frame.pc;
315 } while (count ++ < 16);
316 return 0;
317}
318
319unsigned long arch_randomize_brk(struct mm_struct *mm)
320{
321 return randomize_page(mm->brk, 0x02000000);
322}
323
324#ifdef CONFIG_MMU
325#ifdef CONFIG_KUSER_HELPERS
326/*
327 * The vectors page is always readable from user space for the
328 * atomic helpers. Insert it into the gate_vma so that it is visible
329 * through ptrace and /proc/<pid>/mem.
330 */
331static struct vm_area_struct gate_vma = {
332 .vm_start = 0xffff0000,
333 .vm_end = 0xffff0000 + PAGE_SIZE,
334 .vm_flags = VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYEXEC,
335};
336
337static int __init gate_vma_init(void)
338{
339 gate_vma.vm_page_prot = PAGE_READONLY_EXEC;
340 return 0;
341}
342arch_initcall(gate_vma_init);
343
344struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
345{
346 return &gate_vma;
347}
348
349int in_gate_area(struct mm_struct *mm, unsigned long addr)
350{
351 return (addr >= gate_vma.vm_start) && (addr < gate_vma.vm_end);
352}
353
354int in_gate_area_no_mm(unsigned long addr)
355{
356 return in_gate_area(NULL, addr);
357}
358#define is_gate_vma(vma) ((vma) == &gate_vma)
359#else
360#define is_gate_vma(vma) 0
361#endif
362
363const char *arch_vma_name(struct vm_area_struct *vma)
364{
365 return is_gate_vma(vma) ? "[vectors]" : NULL;
366}
367
368/* If possible, provide a placement hint at a random offset from the
369 * stack for the sigpage and vdso pages.
370 */
371static unsigned long sigpage_addr(const struct mm_struct *mm,
372 unsigned int npages)
373{
374 unsigned long offset;
375 unsigned long first;
376 unsigned long last;
377 unsigned long addr;
378 unsigned int slots;
379
380 first = PAGE_ALIGN(mm->start_stack);
381
382 last = TASK_SIZE - (npages << PAGE_SHIFT);
383
384 /* No room after stack? */
385 if (first > last)
386 return 0;
387
388 /* Just enough room? */
389 if (first == last)
390 return first;
391
392 slots = ((last - first) >> PAGE_SHIFT) + 1;
393
394 offset = get_random_int() % slots;
395
396 addr = first + (offset << PAGE_SHIFT);
397
398 return addr;
399}
400
401static struct page *signal_page;
402extern struct page *get_signal_page(void);
403
404static const struct vm_special_mapping sigpage_mapping = {
405 .name = "[sigpage]",
406 .pages = &signal_page,
407};
408
409int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
410{
411 struct mm_struct *mm = current->mm;
412 struct vm_area_struct *vma;
413 unsigned long npages;
414 unsigned long addr;
415 unsigned long hint;
416 int ret = 0;
417
418 if (!signal_page)
419 signal_page = get_signal_page();
420 if (!signal_page)
421 return -ENOMEM;
422
423 npages = 1; /* for sigpage */
424 npages += vdso_total_pages;
425
426 if (down_write_killable(&mm->mmap_sem))
427 return -EINTR;
428 hint = sigpage_addr(mm, npages);
429 addr = get_unmapped_area(NULL, hint, npages << PAGE_SHIFT, 0, 0);
430 if (IS_ERR_VALUE(addr)) {
431 ret = addr;
432 goto up_fail;
433 }
434
435 vma = _install_special_mapping(mm, addr, PAGE_SIZE,
436 VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC,
437 &sigpage_mapping);
438
439 if (IS_ERR(vma)) {
440 ret = PTR_ERR(vma);
441 goto up_fail;
442 }
443
444 mm->context.sigpage = addr;
445
446 /* Unlike the sigpage, failure to install the vdso is unlikely
447 * to be fatal to the process, so no error check needed
448 * here.
449 */
450 arm_install_vdso(mm, addr + PAGE_SIZE);
451
452 up_fail:
453 up_write(&mm->mmap_sem);
454 return ret;
455}
456#endif