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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/delay.h> |
21 | #include <linux/reboot.h> | |
22 | #include <linux/interrupt.h> | |
23 | #include <linux/kallsyms.h> | |
24 | #include <linux/init.h> | |
a054a811 | 25 | #include <linux/cpu.h> |
84dff1a7 | 26 | #include <linux/elfcore.h> |
74617fb6 | 27 | #include <linux/pm.h> |
9e4559dd | 28 | #include <linux/tick.h> |
154c772e | 29 | #include <linux/utsname.h> |
33fa9b13 | 30 | #include <linux/uaccess.h> |
990cb8ac | 31 | #include <linux/random.h> |
864232fa | 32 | #include <linux/hw_breakpoint.h> |
a0bfa137 | 33 | #include <linux/cpuidle.h> |
1da177e4 | 34 | |
9ca03a21 | 35 | #include <asm/cacheflush.h> |
1da177e4 LT |
36 | #include <asm/leds.h> |
37 | #include <asm/processor.h> | |
78ff18a4 | 38 | #include <asm/system.h> |
d6551e88 | 39 | #include <asm/thread_notify.h> |
2d7c11bf | 40 | #include <asm/stacktrace.h> |
2ea83398 | 41 | #include <asm/mach/time.h> |
1da177e4 | 42 | |
c743f380 NP |
43 | #ifdef CONFIG_CC_STACKPROTECTOR |
44 | #include <linux/stackprotector.h> | |
45 | unsigned long __stack_chk_guard __read_mostly; | |
46 | EXPORT_SYMBOL(__stack_chk_guard); | |
47 | #endif | |
48 | ||
ae0a846e RK |
49 | static const char *processor_modes[] = { |
50 | "USER_26", "FIQ_26" , "IRQ_26" , "SVC_26" , "UK4_26" , "UK5_26" , "UK6_26" , "UK7_26" , | |
51 | "UK8_26" , "UK9_26" , "UK10_26", "UK11_26", "UK12_26", "UK13_26", "UK14_26", "UK15_26", | |
52 | "USER_32", "FIQ_32" , "IRQ_32" , "SVC_32" , "UK4_32" , "UK5_32" , "UK6_32" , "ABT_32" , | |
53 | "UK8_32" , "UK9_32" , "UK10_32", "UND_32" , "UK12_32", "UK13_32", "UK14_32", "SYS_32" | |
54 | }; | |
55 | ||
909d6c6c GD |
56 | static const char *isa_modes[] = { |
57 | "ARM" , "Thumb" , "Jazelle", "ThumbEE" | |
58 | }; | |
59 | ||
5aafec15 | 60 | extern void setup_mm_for_reboot(void); |
1da177e4 LT |
61 | |
62 | static volatile int hlt_counter; | |
63 | ||
a09e64fb | 64 | #include <mach/system.h> |
1da177e4 LT |
65 | |
66 | void disable_hlt(void) | |
67 | { | |
68 | hlt_counter++; | |
69 | } | |
70 | ||
71 | EXPORT_SYMBOL(disable_hlt); | |
72 | ||
73 | void enable_hlt(void) | |
74 | { | |
75 | hlt_counter--; | |
76 | } | |
77 | ||
78 | EXPORT_SYMBOL(enable_hlt); | |
79 | ||
80 | static int __init nohlt_setup(char *__unused) | |
81 | { | |
82 | hlt_counter = 1; | |
83 | return 1; | |
84 | } | |
85 | ||
86 | static int __init hlt_setup(char *__unused) | |
87 | { | |
88 | hlt_counter = 0; | |
89 | return 1; | |
90 | } | |
91 | ||
92 | __setup("nohlt", nohlt_setup); | |
93 | __setup("hlt", hlt_setup); | |
94 | ||
290130a1 WD |
95 | extern void call_with_stack(void (*fn)(void *), void *arg, void *sp); |
96 | typedef void (*phys_reset_t)(unsigned long); | |
97 | ||
98 | /* | |
99 | * A temporary stack to use for CPU reset. This is static so that we | |
100 | * don't clobber it with the identity mapping. When running with this | |
101 | * stack, any references to the current task *will not work* so you | |
102 | * should really do as little as possible before jumping to your reset | |
103 | * code. | |
104 | */ | |
105 | static u64 soft_restart_stack[16]; | |
106 | ||
107 | static void __soft_restart(void *addr) | |
74617fb6 | 108 | { |
290130a1 | 109 | phys_reset_t phys_reset; |
74617fb6 | 110 | |
290130a1 | 111 | /* Take out a flat memory mapping. */ |
5aafec15 | 112 | setup_mm_for_reboot(); |
74617fb6 | 113 | |
9ca03a21 RK |
114 | /* Clean and invalidate caches */ |
115 | flush_cache_all(); | |
116 | ||
117 | /* Turn off caching */ | |
118 | cpu_proc_fin(); | |
119 | ||
120 | /* Push out any further dirty data, and ensure cache is empty */ | |
121 | flush_cache_all(); | |
122 | ||
290130a1 WD |
123 | /* Switch to the identity mapping. */ |
124 | phys_reset = (phys_reset_t)(unsigned long)virt_to_phys(cpu_reset); | |
125 | phys_reset((unsigned long)addr); | |
126 | ||
127 | /* Should never get here. */ | |
128 | BUG(); | |
129 | } | |
130 | ||
131 | void soft_restart(unsigned long addr) | |
132 | { | |
133 | u64 *stack = soft_restart_stack + ARRAY_SIZE(soft_restart_stack); | |
134 | ||
135 | /* Disable interrupts first */ | |
136 | local_irq_disable(); | |
137 | local_fiq_disable(); | |
138 | ||
139 | /* Disable the L2 if we're the last man standing. */ | |
140 | if (num_online_cpus() == 1) | |
141 | outer_disable(); | |
142 | ||
143 | /* Change to the new stack and continue with the reset. */ | |
144 | call_with_stack(__soft_restart, (void *)addr, (void *)stack); | |
145 | ||
146 | /* Should never get here. */ | |
147 | BUG(); | |
e879c862 RK |
148 | } |
149 | ||
150 | void arm_machine_restart(char mode, const char *cmd) | |
151 | { | |
152 | /* Disable interrupts first */ | |
153 | local_irq_disable(); | |
154 | local_fiq_disable(); | |
155 | ||
156 | /* Call the architecture specific reboot code. */ | |
be093beb | 157 | arch_reset(mode, cmd); |
74617fb6 RP |
158 | } |
159 | ||
1da177e4 | 160 | /* |
74617fb6 | 161 | * Function pointers to optional machine specific functions |
1da177e4 | 162 | */ |
1da177e4 LT |
163 | void (*pm_power_off)(void); |
164 | EXPORT_SYMBOL(pm_power_off); | |
165 | ||
be093beb | 166 | void (*arm_pm_restart)(char str, const char *cmd) = arm_machine_restart; |
74617fb6 RP |
167 | EXPORT_SYMBOL_GPL(arm_pm_restart); |
168 | ||
c7b0aff4 KH |
169 | static void do_nothing(void *unused) |
170 | { | |
171 | } | |
172 | ||
173 | /* | |
174 | * cpu_idle_wait - Used to ensure that all the CPUs discard old value of | |
175 | * pm_idle and update to new pm_idle value. Required while changing pm_idle | |
176 | * handler on SMP systems. | |
177 | * | |
178 | * Caller must have changed pm_idle to the new value before the call. Old | |
179 | * pm_idle value will not be used by any CPU after the return of this function. | |
180 | */ | |
181 | void cpu_idle_wait(void) | |
182 | { | |
183 | smp_mb(); | |
184 | /* kick all the CPUs so that they exit out of pm_idle */ | |
185 | smp_call_function(do_nothing, NULL, 1); | |
186 | } | |
187 | EXPORT_SYMBOL_GPL(cpu_idle_wait); | |
74617fb6 | 188 | |
1da177e4 LT |
189 | /* |
190 | * This is our default idle handler. We need to disable | |
191 | * interrupts here to ensure we don't miss a wakeup call. | |
192 | */ | |
84dff1a7 | 193 | static void default_idle(void) |
1da177e4 | 194 | { |
9ccdac36 RK |
195 | if (!need_resched()) |
196 | arch_idle(); | |
197 | local_irq_enable(); | |
1da177e4 LT |
198 | } |
199 | ||
9ccdac36 RK |
200 | void (*pm_idle)(void) = default_idle; |
201 | EXPORT_SYMBOL(pm_idle); | |
202 | ||
1da177e4 | 203 | /* |
9ccdac36 RK |
204 | * The idle thread, has rather strange semantics for calling pm_idle, |
205 | * but this is what x86 does and we need to do the same, so that | |
206 | * things like cpuidle get called in the same way. The only difference | |
207 | * is that we always respect 'hlt_counter' to prevent low power idle. | |
1da177e4 LT |
208 | */ |
209 | void cpu_idle(void) | |
210 | { | |
211 | local_fiq_enable(); | |
212 | ||
213 | /* endless idle loop with no priority at all */ | |
214 | while (1) { | |
9ccdac36 RK |
215 | tick_nohz_stop_sched_tick(1); |
216 | leds_event(led_idle_start); | |
217 | while (!need_resched()) { | |
a054a811 | 218 | #ifdef CONFIG_HOTPLUG_CPU |
9ccdac36 RK |
219 | if (cpu_is_offline(smp_processor_id())) |
220 | cpu_die(); | |
a054a811 RK |
221 | #endif |
222 | ||
9ccdac36 | 223 | local_irq_disable(); |
11ed0ba1 WD |
224 | #ifdef CONFIG_PL310_ERRATA_769419 |
225 | wmb(); | |
226 | #endif | |
9ccdac36 RK |
227 | if (hlt_counter) { |
228 | local_irq_enable(); | |
229 | cpu_relax(); | |
230 | } else { | |
231 | stop_critical_timings(); | |
cbc158d6 | 232 | if (cpuidle_idle_call()) |
a0bfa137 | 233 | pm_idle(); |
9ccdac36 RK |
234 | start_critical_timings(); |
235 | /* | |
236 | * This will eventually be removed - pm_idle | |
237 | * functions should always return with IRQs | |
238 | * enabled. | |
239 | */ | |
240 | WARN_ON(irqs_disabled()); | |
241 | local_irq_enable(); | |
242 | } | |
243 | } | |
1da177e4 | 244 | leds_event(led_idle_end); |
9e4559dd | 245 | tick_nohz_restart_sched_tick(); |
5bfb5d69 | 246 | preempt_enable_no_resched(); |
1da177e4 | 247 | schedule(); |
5bfb5d69 | 248 | preempt_disable(); |
1da177e4 LT |
249 | } |
250 | } | |
251 | ||
252 | static char reboot_mode = 'h'; | |
253 | ||
254 | int __init reboot_setup(char *str) | |
255 | { | |
256 | reboot_mode = str[0]; | |
257 | return 1; | |
258 | } | |
259 | ||
260 | __setup("reboot=", reboot_setup); | |
261 | ||
3d3f78d7 | 262 | void machine_shutdown(void) |
1da177e4 | 263 | { |
3d3f78d7 RK |
264 | #ifdef CONFIG_SMP |
265 | smp_send_stop(); | |
266 | #endif | |
1da177e4 LT |
267 | } |
268 | ||
3d3f78d7 RK |
269 | void machine_halt(void) |
270 | { | |
271 | machine_shutdown(); | |
272 | while (1); | |
273 | } | |
1da177e4 LT |
274 | |
275 | void machine_power_off(void) | |
276 | { | |
3d3f78d7 | 277 | machine_shutdown(); |
1da177e4 LT |
278 | if (pm_power_off) |
279 | pm_power_off(); | |
280 | } | |
281 | ||
be093beb | 282 | void machine_restart(char *cmd) |
1da177e4 | 283 | { |
3d3f78d7 | 284 | machine_shutdown(); |
ac15e00b | 285 | |
be093beb | 286 | arm_pm_restart(reboot_mode, cmd); |
ac15e00b RK |
287 | |
288 | /* Give a grace period for failure to restart of 1s */ | |
289 | mdelay(1000); | |
290 | ||
291 | /* Whoops - the platform was unable to reboot. Tell the user! */ | |
292 | printk("Reboot failed -- System halted\n"); | |
293 | while (1); | |
1da177e4 LT |
294 | } |
295 | ||
652a12ef | 296 | void __show_regs(struct pt_regs *regs) |
1da177e4 | 297 | { |
154c772e RK |
298 | unsigned long flags; |
299 | char buf[64]; | |
1da177e4 | 300 | |
154c772e | 301 | printk("CPU: %d %s (%s %.*s)\n", |
22325525 RV |
302 | raw_smp_processor_id(), print_tainted(), |
303 | init_utsname()->release, | |
154c772e RK |
304 | (int)strcspn(init_utsname()->version, " "), |
305 | init_utsname()->version); | |
1da177e4 LT |
306 | print_symbol("PC is at %s\n", instruction_pointer(regs)); |
307 | print_symbol("LR is at %s\n", regs->ARM_lr); | |
154c772e | 308 | printk("pc : [<%08lx>] lr : [<%08lx>] psr: %08lx\n" |
1da177e4 | 309 | "sp : %08lx ip : %08lx fp : %08lx\n", |
154c772e RK |
310 | regs->ARM_pc, regs->ARM_lr, regs->ARM_cpsr, |
311 | regs->ARM_sp, regs->ARM_ip, regs->ARM_fp); | |
1da177e4 LT |
312 | printk("r10: %08lx r9 : %08lx r8 : %08lx\n", |
313 | regs->ARM_r10, regs->ARM_r9, | |
314 | regs->ARM_r8); | |
315 | printk("r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n", | |
316 | regs->ARM_r7, regs->ARM_r6, | |
317 | regs->ARM_r5, regs->ARM_r4); | |
318 | printk("r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n", | |
319 | regs->ARM_r3, regs->ARM_r2, | |
320 | regs->ARM_r1, regs->ARM_r0); | |
154c772e RK |
321 | |
322 | flags = regs->ARM_cpsr; | |
323 | buf[0] = flags & PSR_N_BIT ? 'N' : 'n'; | |
324 | buf[1] = flags & PSR_Z_BIT ? 'Z' : 'z'; | |
325 | buf[2] = flags & PSR_C_BIT ? 'C' : 'c'; | |
326 | buf[3] = flags & PSR_V_BIT ? 'V' : 'v'; | |
327 | buf[4] = '\0'; | |
328 | ||
909d6c6c | 329 | printk("Flags: %s IRQs o%s FIQs o%s Mode %s ISA %s Segment %s\n", |
154c772e | 330 | buf, interrupts_enabled(regs) ? "n" : "ff", |
1da177e4 LT |
331 | fast_interrupts_enabled(regs) ? "n" : "ff", |
332 | processor_modes[processor_mode(regs)], | |
909d6c6c | 333 | isa_modes[isa_mode(regs)], |
1da177e4 | 334 | get_fs() == get_ds() ? "kernel" : "user"); |
154c772e | 335 | #ifdef CONFIG_CPU_CP15 |
1da177e4 | 336 | { |
f12d0d7c | 337 | unsigned int ctrl; |
154c772e RK |
338 | |
339 | buf[0] = '\0'; | |
f12d0d7c | 340 | #ifdef CONFIG_CPU_CP15_MMU |
154c772e RK |
341 | { |
342 | unsigned int transbase, dac; | |
343 | asm("mrc p15, 0, %0, c2, c0\n\t" | |
344 | "mrc p15, 0, %1, c3, c0\n" | |
345 | : "=r" (transbase), "=r" (dac)); | |
346 | snprintf(buf, sizeof(buf), " Table: %08x DAC: %08x", | |
347 | transbase, dac); | |
348 | } | |
f12d0d7c | 349 | #endif |
154c772e RK |
350 | asm("mrc p15, 0, %0, c1, c0\n" : "=r" (ctrl)); |
351 | ||
352 | printk("Control: %08x%s\n", ctrl, buf); | |
353 | } | |
f12d0d7c | 354 | #endif |
1da177e4 LT |
355 | } |
356 | ||
652a12ef RK |
357 | void show_regs(struct pt_regs * regs) |
358 | { | |
359 | printk("\n"); | |
19c5870c | 360 | printk("Pid: %d, comm: %20s\n", task_pid_nr(current), current->comm); |
652a12ef | 361 | __show_regs(regs); |
b380ab4f | 362 | dump_stack(); |
652a12ef RK |
363 | } |
364 | ||
797245f5 RK |
365 | ATOMIC_NOTIFIER_HEAD(thread_notify_head); |
366 | ||
367 | EXPORT_SYMBOL_GPL(thread_notify_head); | |
368 | ||
1da177e4 LT |
369 | /* |
370 | * Free current thread data structures etc.. | |
371 | */ | |
372 | void exit_thread(void) | |
373 | { | |
797245f5 | 374 | thread_notify(THREAD_NOTIFY_EXIT, current_thread_info()); |
1da177e4 LT |
375 | } |
376 | ||
1da177e4 LT |
377 | void flush_thread(void) |
378 | { | |
379 | struct thread_info *thread = current_thread_info(); | |
380 | struct task_struct *tsk = current; | |
381 | ||
864232fa WD |
382 | flush_ptrace_hw_breakpoint(tsk); |
383 | ||
1da177e4 LT |
384 | memset(thread->used_cp, 0, sizeof(thread->used_cp)); |
385 | memset(&tsk->thread.debug, 0, sizeof(struct debug_info)); | |
d6551e88 RK |
386 | memset(&thread->fpstate, 0, sizeof(union fp_state)); |
387 | ||
388 | thread_notify(THREAD_NOTIFY_FLUSH, thread); | |
1da177e4 LT |
389 | } |
390 | ||
391 | void release_thread(struct task_struct *dead_task) | |
392 | { | |
1da177e4 LT |
393 | } |
394 | ||
395 | asmlinkage void ret_from_fork(void) __asm__("ret_from_fork"); | |
396 | ||
397 | int | |
6f2c55b8 | 398 | copy_thread(unsigned long clone_flags, unsigned long stack_start, |
1da177e4 LT |
399 | unsigned long stk_sz, struct task_struct *p, struct pt_regs *regs) |
400 | { | |
815d5ec8 AV |
401 | struct thread_info *thread = task_thread_info(p); |
402 | struct pt_regs *childregs = task_pt_regs(p); | |
1da177e4 | 403 | |
1da177e4 LT |
404 | *childregs = *regs; |
405 | childregs->ARM_r0 = 0; | |
406 | childregs->ARM_sp = stack_start; | |
407 | ||
408 | memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save)); | |
409 | thread->cpu_context.sp = (unsigned long)childregs; | |
410 | thread->cpu_context.pc = (unsigned long)ret_from_fork; | |
411 | ||
864232fa WD |
412 | clear_ptrace_hw_breakpoint(p); |
413 | ||
1da177e4 LT |
414 | if (clone_flags & CLONE_SETTLS) |
415 | thread->tp_value = regs->ARM_r3; | |
416 | ||
2e82669a CM |
417 | thread_notify(THREAD_NOTIFY_COPY, thread); |
418 | ||
1da177e4 LT |
419 | return 0; |
420 | } | |
421 | ||
cde3f860 AB |
422 | /* |
423 | * Fill in the task's elfregs structure for a core dump. | |
424 | */ | |
425 | int dump_task_regs(struct task_struct *t, elf_gregset_t *elfregs) | |
426 | { | |
427 | elf_core_copy_regs(elfregs, task_pt_regs(t)); | |
428 | return 1; | |
429 | } | |
430 | ||
1da177e4 LT |
431 | /* |
432 | * fill in the fpe structure for a core dump... | |
433 | */ | |
434 | int dump_fpu (struct pt_regs *regs, struct user_fp *fp) | |
435 | { | |
436 | struct thread_info *thread = current_thread_info(); | |
437 | int used_math = thread->used_cp[1] | thread->used_cp[2]; | |
438 | ||
439 | if (used_math) | |
440 | memcpy(fp, &thread->fpstate.soft, sizeof (*fp)); | |
441 | ||
442 | return used_math != 0; | |
443 | } | |
444 | EXPORT_SYMBOL(dump_fpu); | |
445 | ||
1da177e4 LT |
446 | /* |
447 | * Shuffle the argument into the correct register before calling the | |
ac78884e RK |
448 | * thread function. r4 is the thread argument, r5 is the pointer to |
449 | * the thread function, and r6 points to the exit function. | |
1da177e4 LT |
450 | */ |
451 | extern void kernel_thread_helper(void); | |
4260415f | 452 | asm( ".pushsection .text\n" |
1da177e4 LT |
453 | " .align\n" |
454 | " .type kernel_thread_helper, #function\n" | |
455 | "kernel_thread_helper:\n" | |
ac78884e RK |
456 | #ifdef CONFIG_TRACE_IRQFLAGS |
457 | " bl trace_hardirqs_on\n" | |
458 | #endif | |
459 | " msr cpsr_c, r7\n" | |
460 | " mov r0, r4\n" | |
461 | " mov lr, r6\n" | |
462 | " mov pc, r5\n" | |
1da177e4 | 463 | " .size kernel_thread_helper, . - kernel_thread_helper\n" |
4260415f | 464 | " .popsection"); |
1da177e4 | 465 | |
feb97c36 CM |
466 | #ifdef CONFIG_ARM_UNWIND |
467 | extern void kernel_thread_exit(long code); | |
4260415f | 468 | asm( ".pushsection .text\n" |
feb97c36 CM |
469 | " .align\n" |
470 | " .type kernel_thread_exit, #function\n" | |
471 | "kernel_thread_exit:\n" | |
472 | " .fnstart\n" | |
473 | " .cantunwind\n" | |
474 | " bl do_exit\n" | |
475 | " nop\n" | |
476 | " .fnend\n" | |
477 | " .size kernel_thread_exit, . - kernel_thread_exit\n" | |
4260415f | 478 | " .popsection"); |
feb97c36 CM |
479 | #else |
480 | #define kernel_thread_exit do_exit | |
481 | #endif | |
482 | ||
1da177e4 LT |
483 | /* |
484 | * Create a kernel thread. | |
485 | */ | |
486 | pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags) | |
487 | { | |
488 | struct pt_regs regs; | |
489 | ||
490 | memset(®s, 0, sizeof(regs)); | |
491 | ||
ac78884e RK |
492 | regs.ARM_r4 = (unsigned long)arg; |
493 | regs.ARM_r5 = (unsigned long)fn; | |
494 | regs.ARM_r6 = (unsigned long)kernel_thread_exit; | |
495 | regs.ARM_r7 = SVC_MODE | PSR_ENDSTATE | PSR_ISETSTATE; | |
1da177e4 | 496 | regs.ARM_pc = (unsigned long)kernel_thread_helper; |
ac78884e | 497 | regs.ARM_cpsr = regs.ARM_r7 | PSR_I_BIT; |
1da177e4 LT |
498 | |
499 | return do_fork(flags|CLONE_VM|CLONE_UNTRACED, 0, ®s, 0, NULL, NULL); | |
500 | } | |
501 | EXPORT_SYMBOL(kernel_thread); | |
502 | ||
503 | unsigned long get_wchan(struct task_struct *p) | |
504 | { | |
2d7c11bf | 505 | struct stackframe frame; |
1da177e4 LT |
506 | int count = 0; |
507 | if (!p || p == current || p->state == TASK_RUNNING) | |
508 | return 0; | |
509 | ||
2d7c11bf CM |
510 | frame.fp = thread_saved_fp(p); |
511 | frame.sp = thread_saved_sp(p); | |
512 | frame.lr = 0; /* recovered from the stack */ | |
513 | frame.pc = thread_saved_pc(p); | |
1da177e4 | 514 | do { |
2d7c11bf CM |
515 | int ret = unwind_frame(&frame); |
516 | if (ret < 0) | |
1da177e4 | 517 | return 0; |
2d7c11bf CM |
518 | if (!in_sched_functions(frame.pc)) |
519 | return frame.pc; | |
1da177e4 LT |
520 | } while (count ++ < 16); |
521 | return 0; | |
522 | } | |
990cb8ac NP |
523 | |
524 | unsigned long arch_randomize_brk(struct mm_struct *mm) | |
525 | { | |
526 | unsigned long range_end = mm->brk + 0x02000000; | |
527 | return randomize_range(mm->brk, range_end, 0) ? : mm->brk; | |
528 | } | |
ec706dab | 529 | |
6cde6d42 | 530 | #ifdef CONFIG_MMU |
ec706dab NP |
531 | /* |
532 | * The vectors page is always readable from user space for the | |
533 | * atomic helpers and the signal restart code. Let's declare a mapping | |
534 | * for it so it is visible through ptrace and /proc/<pid>/mem. | |
535 | */ | |
536 | ||
537 | int vectors_user_mapping(void) | |
538 | { | |
539 | struct mm_struct *mm = current->mm; | |
540 | return install_special_mapping(mm, 0xffff0000, PAGE_SIZE, | |
541 | VM_READ | VM_EXEC | | |
542 | VM_MAYREAD | VM_MAYEXEC | | |
543 | VM_ALWAYSDUMP | VM_RESERVED, | |
544 | NULL); | |
545 | } | |
546 | ||
547 | const char *arch_vma_name(struct vm_area_struct *vma) | |
548 | { | |
549 | return (vma->vm_start == 0xffff0000) ? "[vectors]" : NULL; | |
550 | } | |
6cde6d42 | 551 | #endif |