72 lines
1.5 KiB
C
72 lines
1.5 KiB
C
![]() |
/*
|
||
|
* arch/arm/kernel/return_address.c
|
||
|
*
|
||
|
* Copyright (C) 2009 Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
|
||
|
* for Pengutronix
|
||
|
*
|
||
|
* This program is free software; you can redistribute it and/or modify it
|
||
|
* under the terms of the GNU General Public License version 2 as published by
|
||
|
* the Free Software Foundation.
|
||
|
*/
|
||
|
#include <linux/module.h>
|
||
|
|
||
|
#if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND)
|
||
|
#include <linux/sched.h>
|
||
|
|
||
|
#include <asm/stacktrace.h>
|
||
|
|
||
|
struct return_address_data {
|
||
|
unsigned int level;
|
||
|
void *addr;
|
||
|
};
|
||
|
|
||
|
static int save_return_addr(struct stackframe *frame, void *d)
|
||
|
{
|
||
|
struct return_address_data *data = d;
|
||
|
|
||
|
if (!data->level) {
|
||
|
data->addr = (void *)frame->lr;
|
||
|
|
||
|
return 1;
|
||
|
} else {
|
||
|
--data->level;
|
||
|
return 0;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
void *return_address(unsigned int level)
|
||
|
{
|
||
|
struct return_address_data data;
|
||
|
struct stackframe frame;
|
||
|
register unsigned long current_sp asm ("sp");
|
||
|
|
||
|
data.level = level + 1;
|
||
|
|
||
|
frame.fp = (unsigned long)__builtin_frame_address(0);
|
||
|
frame.sp = current_sp;
|
||
|
frame.lr = (unsigned long)__builtin_return_address(0);
|
||
|
frame.pc = (unsigned long)return_address;
|
||
|
|
||
|
walk_stackframe(&frame, save_return_addr, &data);
|
||
|
|
||
|
if (!data.level)
|
||
|
return data.addr;
|
||
|
else
|
||
|
return NULL;
|
||
|
}
|
||
|
|
||
|
#else /* if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND) */
|
||
|
|
||
|
#if defined(CONFIG_ARM_UNWIND)
|
||
|
#warning "TODO: return_address should use unwind tables"
|
||
|
#endif
|
||
|
|
||
|
void *return_address(unsigned int level)
|
||
|
{
|
||
|
return NULL;
|
||
|
}
|
||
|
|
||
|
#endif /* if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND) / else */
|
||
|
|
||
|
EXPORT_SYMBOL_GPL(return_address);
|