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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/leds.h>
34#include <linux/reboot.h>
35
36#include <asm/cacheflush.h>
37#include <asm/idmap.h>
38#include <asm/processor.h>
39#include <asm/thread_notify.h>
40#include <asm/stacktrace.h>
41#include <asm/system_misc.h>
42#include <asm/mach/time.h>
43#include <asm/tls.h>
44
45#ifdef CONFIG_CC_STACKPROTECTOR
46#include <linux/stackprotector.h>
47unsigned long __stack_chk_guard __read_mostly;
48EXPORT_SYMBOL(__stack_chk_guard);
49#endif
50
51static const char *processor_modes[] __maybe_unused = {
52 "USER_26", "FIQ_26" , "IRQ_26" , "SVC_26" , "UK4_26" , "UK5_26" , "UK6_26" , "UK7_26" ,
53 "UK8_26" , "UK9_26" , "UK10_26", "UK11_26", "UK12_26", "UK13_26", "UK14_26", "UK15_26",
54 "USER_32", "FIQ_32" , "IRQ_32" , "SVC_32" , "UK4_32" , "UK5_32" , "UK6_32" , "ABT_32" ,
55 "UK8_32" , "UK9_32" , "UK10_32", "UND_32" , "UK12_32", "UK13_32", "UK14_32", "SYS_32"
56};
57
58static const char *isa_modes[] __maybe_unused = {
59 "ARM" , "Thumb" , "Jazelle", "ThumbEE"
60};
61
62extern void call_with_stack(void (*fn)(void *), void *arg, void *sp);
63typedef void (*phys_reset_t)(unsigned long);
64
65/*
66 * A temporary stack to use for CPU reset. This is static so that we
67 * don't clobber it with the identity mapping. When running with this
68 * stack, any references to the current task *will not work* so you
69 * should really do as little as possible before jumping to your reset
70 * code.
71 */
72static u64 soft_restart_stack[16];
73
74static void __soft_restart(void *addr)
75{
76 phys_reset_t phys_reset;
77
78 /* Take out a flat memory mapping. */
79 setup_mm_for_reboot();
80
81 /* Clean and invalidate caches */
82 flush_cache_all();
83
84 /* Turn off caching */
85 cpu_proc_fin();
86
87 /* Push out any further dirty data, and ensure cache is empty */
88 flush_cache_all();
89
90 /* Switch to the identity mapping. */
91 phys_reset = (phys_reset_t)(unsigned long)virt_to_phys(cpu_reset);
92 phys_reset((unsigned long)addr);
93
94 /* Should never get here. */
95 BUG();
96}
97
98void soft_restart(unsigned long addr)
99{
100 u64 *stack = soft_restart_stack + ARRAY_SIZE(soft_restart_stack);
101
102 /* Disable interrupts first */
103 raw_local_irq_disable();
104 local_fiq_disable();
105
106 /* Disable the L2 if we're the last man standing. */
107 if (num_online_cpus() == 1)
108 outer_disable();
109
110 /* Change to the new stack and continue with the reset. */
111 call_with_stack(__soft_restart, (void *)addr, (void *)stack);
112
113 /* Should never get here. */
114 BUG();
115}
116
117static void null_restart(enum reboot_mode reboot_mode, const char *cmd)
118{
119}
120
121/*
122 * Function pointers to optional machine specific functions
123 */
124void (*pm_power_off)(void);
125EXPORT_SYMBOL(pm_power_off);
126
127void (*arm_pm_restart)(enum reboot_mode reboot_mode, const char *cmd) = null_restart;
128EXPORT_SYMBOL_GPL(arm_pm_restart);
129
130/*
131 * This is our default idle handler.
132 */
133
134void (*arm_pm_idle)(void);
135
136/*
137 * Called from the core idle loop.
138 */
139
140void arch_cpu_idle(void)
141{
142 if (arm_pm_idle)
143 arm_pm_idle();
144 else
145 cpu_do_idle();
146 local_irq_enable();
147}
148
149void arch_cpu_idle_prepare(void)
150{
151 local_fiq_enable();
152}
153
154void arch_cpu_idle_enter(void)
155{
156 ledtrig_cpu(CPU_LED_IDLE_START);
157#ifdef CONFIG_PL310_ERRATA_769419
158 wmb();
159#endif
160}
161
162void arch_cpu_idle_exit(void)
163{
164 ledtrig_cpu(CPU_LED_IDLE_END);
165}
166
167#ifdef CONFIG_HOTPLUG_CPU
168void arch_cpu_idle_dead(void)
169{
170 cpu_die();
171}
172#endif
173
174/*
175 * Called by kexec, immediately prior to machine_kexec().
176 *
177 * This must completely disable all secondary CPUs; simply causing those CPUs
178 * to execute e.g. a RAM-based pin loop is not sufficient. This allows the
179 * kexec'd kernel to use any and all RAM as it sees fit, without having to
180 * avoid any code or data used by any SW CPU pin loop. The CPU hotplug
181 * functionality embodied in disable_nonboot_cpus() to achieve this.
182 */
183void machine_shutdown(void)
184{
185 disable_nonboot_cpus();
186}
187
188/*
189 * Halting simply requires that the secondary CPUs stop performing any
190 * activity (executing tasks, handling interrupts). smp_send_stop()
191 * achieves this.
192 */
193void machine_halt(void)
194{
195 local_irq_disable();
196 smp_send_stop();
197
198 local_irq_disable();
199 while (1);
200}
201
202/*
203 * Power-off simply requires that the secondary CPUs stop performing any
204 * activity (executing tasks, handling interrupts). smp_send_stop()
205 * achieves this. When the system power is turned off, it will take all CPUs
206 * with it.
207 */
208void machine_power_off(void)
209{
210 local_irq_disable();
211 smp_send_stop();
212
213 if (pm_power_off)
214 pm_power_off();
215}
216
217/*
218 * Restart requires that the secondary CPUs stop performing any activity
219 * while the primary CPU resets the system. Systems with a single CPU can
220 * use soft_restart() as their machine descriptor's .restart hook, since that
221 * will cause the only available CPU to reset. Systems with multiple CPUs must
222 * provide a HW restart implementation, to ensure that all CPUs reset at once.
223 * This is required so that any code running after reset on the primary CPU
224 * doesn't have to co-ordinate with other CPUs to ensure they aren't still
225 * executing pre-reset code, and using RAM that the primary CPU's code wishes
226 * to use. Implementing such co-ordination would be essentially impossible.
227 */
228void machine_restart(char *cmd)
229{
230 local_irq_disable();
231 smp_send_stop();
232
233 arm_pm_restart(reboot_mode, cmd);
234
235 /* Give a grace period for failure to restart of 1s */
236 mdelay(1000);
237
238 /* Whoops - the platform was unable to reboot. Tell the user! */
239 printk("Reboot failed -- System halted\n");
240 local_irq_disable();
241 while (1);
242}
243
244void __show_regs(struct pt_regs *regs)
245{
246 unsigned long flags;
247 char buf[64];
248
249 show_regs_print_info(KERN_DEFAULT);
250
251 print_symbol("PC is at %s\n", instruction_pointer(regs));
252 print_symbol("LR is at %s\n", regs->ARM_lr);
253 printk("pc : [<%08lx>] lr : [<%08lx>] psr: %08lx\n"
254 "sp : %08lx ip : %08lx fp : %08lx\n",
255 regs->ARM_pc, regs->ARM_lr, regs->ARM_cpsr,
256 regs->ARM_sp, regs->ARM_ip, regs->ARM_fp);
257 printk("r10: %08lx r9 : %08lx r8 : %08lx\n",
258 regs->ARM_r10, regs->ARM_r9,
259 regs->ARM_r8);
260 printk("r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n",
261 regs->ARM_r7, regs->ARM_r6,
262 regs->ARM_r5, regs->ARM_r4);
263 printk("r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n",
264 regs->ARM_r3, regs->ARM_r2,
265 regs->ARM_r1, regs->ARM_r0);
266
267 flags = regs->ARM_cpsr;
268 buf[0] = flags & PSR_N_BIT ? 'N' : 'n';
269 buf[1] = flags & PSR_Z_BIT ? 'Z' : 'z';
270 buf[2] = flags & PSR_C_BIT ? 'C' : 'c';
271 buf[3] = flags & PSR_V_BIT ? 'V' : 'v';
272 buf[4] = '\0';
273
274#ifndef CONFIG_CPU_V7M
275 printk("Flags: %s IRQs o%s FIQs o%s Mode %s ISA %s Segment %s\n",
276 buf, interrupts_enabled(regs) ? "n" : "ff",
277 fast_interrupts_enabled(regs) ? "n" : "ff",
278 processor_modes[processor_mode(regs)],
279 isa_modes[isa_mode(regs)],
280 get_fs() == get_ds() ? "kernel" : "user");
281#else
282 printk("xPSR: %08lx\n", regs->ARM_cpsr);
283#endif
284
285#ifdef CONFIG_CPU_CP15
286 {
287 unsigned int ctrl;
288
289 buf[0] = '\0';
290#ifdef CONFIG_CPU_CP15_MMU
291 {
292 unsigned int transbase, dac;
293 asm("mrc p15, 0, %0, c2, c0\n\t"
294 "mrc p15, 0, %1, c3, c0\n"
295 : "=r" (transbase), "=r" (dac));
296 snprintf(buf, sizeof(buf), " Table: %08x DAC: %08x",
297 transbase, dac);
298 }
299#endif
300 asm("mrc p15, 0, %0, c1, c0\n" : "=r" (ctrl));
301
302 printk("Control: %08x%s\n", ctrl, buf);
303 }
304#endif
305}
306
307void show_regs(struct pt_regs * regs)
308{
309 printk("\n");
310 __show_regs(regs);
311 dump_stack();
312}
313
314ATOMIC_NOTIFIER_HEAD(thread_notify_head);
315
316EXPORT_SYMBOL_GPL(thread_notify_head);
317
318/*
319 * Free current thread data structures etc..
320 */
321void exit_thread(void)
322{
323 thread_notify(THREAD_NOTIFY_EXIT, current_thread_info());
324}
325
326void flush_thread(void)
327{
328 struct thread_info *thread = current_thread_info();
329 struct task_struct *tsk = current;
330
331 flush_ptrace_hw_breakpoint(tsk);
332
333 memset(thread->used_cp, 0, sizeof(thread->used_cp));
334 memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
335 memset(&thread->fpstate, 0, sizeof(union fp_state));
336
337 thread_notify(THREAD_NOTIFY_FLUSH, thread);
338}
339
340void release_thread(struct task_struct *dead_task)
341{
342}
343
344asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
345
346int
347copy_thread(unsigned long clone_flags, unsigned long stack_start,
348 unsigned long stk_sz, struct task_struct *p)
349{
350 struct thread_info *thread = task_thread_info(p);
351 struct pt_regs *childregs = task_pt_regs(p);
352
353 memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save));
354
355 if (likely(!(p->flags & PF_KTHREAD))) {
356 *childregs = *current_pt_regs();
357 childregs->ARM_r0 = 0;
358 if (stack_start)
359 childregs->ARM_sp = stack_start;
360 } else {
361 memset(childregs, 0, sizeof(struct pt_regs));
362 thread->cpu_context.r4 = stk_sz;
363 thread->cpu_context.r5 = stack_start;
364 childregs->ARM_cpsr = SVC_MODE;
365 }
366 thread->cpu_context.pc = (unsigned long)ret_from_fork;
367 thread->cpu_context.sp = (unsigned long)childregs;
368
369 clear_ptrace_hw_breakpoint(p);
370
371 if (clone_flags & CLONE_SETTLS)
372 thread->tp_value[0] = childregs->ARM_r3;
373 thread->tp_value[1] = get_tpuser();
374
375 thread_notify(THREAD_NOTIFY_COPY, thread);
376
377 return 0;
378}
379
380/*
381 * Fill in the task's elfregs structure for a core dump.
382 */
383int dump_task_regs(struct task_struct *t, elf_gregset_t *elfregs)
384{
385 elf_core_copy_regs(elfregs, task_pt_regs(t));
386 return 1;
387}
388
389/*
390 * fill in the fpe structure for a core dump...
391 */
392int dump_fpu (struct pt_regs *regs, struct user_fp *fp)
393{
394 struct thread_info *thread = current_thread_info();
395 int used_math = thread->used_cp[1] | thread->used_cp[2];
396
397 if (used_math)
398 memcpy(fp, &thread->fpstate.soft, sizeof (*fp));
399
400 return used_math != 0;
401}
402EXPORT_SYMBOL(dump_fpu);
403
404unsigned long get_wchan(struct task_struct *p)
405{
406 struct stackframe frame;
407 unsigned long stack_page;
408 int count = 0;
409 if (!p || p == current || p->state == TASK_RUNNING)
410 return 0;
411
412 frame.fp = thread_saved_fp(p);
413 frame.sp = thread_saved_sp(p);
414 frame.lr = 0; /* recovered from the stack */
415 frame.pc = thread_saved_pc(p);
416 stack_page = (unsigned long)task_stack_page(p);
417 do {
418 if (frame.sp < stack_page ||
419 frame.sp >= stack_page + THREAD_SIZE ||
420 unwind_frame(&frame) < 0)
421 return 0;
422 if (!in_sched_functions(frame.pc))
423 return frame.pc;
424 } while (count ++ < 16);
425 return 0;
426}
427
428unsigned long arch_randomize_brk(struct mm_struct *mm)
429{
430 unsigned long range_end = mm->brk + 0x02000000;
431 return randomize_range(mm->brk, range_end, 0) ? : mm->brk;
432}
433
434#ifdef CONFIG_MMU
435#ifdef CONFIG_KUSER_HELPERS
436/*
437 * The vectors page is always readable from user space for the
438 * atomic helpers. Insert it into the gate_vma so that it is visible
439 * through ptrace and /proc/<pid>/mem.
440 */
441static struct vm_area_struct gate_vma = {
442 .vm_start = 0xffff0000,
443 .vm_end = 0xffff0000 + PAGE_SIZE,
444 .vm_flags = VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYEXEC,
445};
446
447static int __init gate_vma_init(void)
448{
449 gate_vma.vm_page_prot = PAGE_READONLY_EXEC;
450 return 0;
451}
452arch_initcall(gate_vma_init);
453
454struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
455{
456 return &gate_vma;
457}
458
459int in_gate_area(struct mm_struct *mm, unsigned long addr)
460{
461 return (addr >= gate_vma.vm_start) && (addr < gate_vma.vm_end);
462}
463
464int in_gate_area_no_mm(unsigned long addr)
465{
466 return in_gate_area(NULL, addr);
467}
468#define is_gate_vma(vma) ((vma) == &gate_vma)
469#else
470#define is_gate_vma(vma) 0
471#endif
472
473const char *arch_vma_name(struct vm_area_struct *vma)
474{
475 return is_gate_vma(vma) ? "[vectors]" :
476 (vma->vm_mm && vma->vm_start == vma->vm_mm->context.sigpage) ?
477 "[sigpage]" : NULL;
478}
479
480static struct page *signal_page;
481extern struct page *get_signal_page(void);
482
483int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
484{
485 struct mm_struct *mm = current->mm;
486 unsigned long addr;
487 int ret;
488
489 if (!signal_page)
490 signal_page = get_signal_page();
491 if (!signal_page)
492 return -ENOMEM;
493
494 down_write(&mm->mmap_sem);
495 addr = get_unmapped_area(NULL, 0, PAGE_SIZE, 0, 0);
496 if (IS_ERR_VALUE(addr)) {
497 ret = addr;
498 goto up_fail;
499 }
500
501 ret = install_special_mapping(mm, addr, PAGE_SIZE,
502 VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC,
503 &signal_page);
504
505 if (ret == 0)
506 mm->context.sigpage = addr;
507
508 up_fail:
509 up_write(&mm->mmap_sem);
510 return ret;
511}
512#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