From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Andr=C3=A9=20Fabian=20Silva=20Delgado?= Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- arch/arm/kernel/return_address.c | 61 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 61 insertions(+) create mode 100644 arch/arm/kernel/return_address.c (limited to 'arch/arm/kernel/return_address.c') diff --git a/arch/arm/kernel/return_address.c b/arch/arm/kernel/return_address.c new file mode 100644 index 000000000..36ed35073 --- /dev/null +++ b/arch/arm/kernel/return_address.c @@ -0,0 +1,61 @@ +/* + * arch/arm/kernel/return_address.c + * + * Copyright (C) 2009 Uwe Kleine-Koenig + * 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 +#include + +#if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND) +#include + +#include + +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->pc; + + return 1; + } else { + --data->level; + return 0; + } +} + +void *return_address(unsigned int level) +{ + struct return_address_data data; + struct stackframe frame; + + data.level = level + 2; + data.addr = NULL; + + frame.fp = (unsigned long)__builtin_frame_address(0); + frame.sp = current_stack_pointer; + 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; +} + +#endif /* if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND) */ + +EXPORT_SYMBOL_GPL(return_address); -- cgit v1.2.3