1/*-
2 * Copyright (c) 2005 Antoine Brodin
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD$");
29
30#include <sys/systm.h>
31#include <sys/param.h>
32#include <sys/proc.h>
33#include <sys/stack.h>
34
35#include <machine/vmparam.h>
36#include <machine/pcb.h>
37#include <machine/stack.h>
38
39/*
40 * This code makes assumptions about the stack layout. These are correct
41 * when using APCS (the old ABI), but are no longer true with AAPCS and the
42 * ARM EABI. There is also an issue with clang and llvm when building for
43 * APCS where it lays out the stack incorrectly. Because of this we disable
44 * this when building for ARM EABI or when building with clang.
45 */
46
47extern vm_offset_t kernel_vm_end;
48
49static void
50stack_capture(struct stack *st, u_int32_t *frame)
51{
52#if !defined(__ARM_EABI__) && !defined(__clang__)
53	vm_offset_t callpc;
54
55	while (INKERNEL(frame) && (vm_offset_t)frame < kernel_vm_end) {
56		callpc = frame[FR_SCP];
57		if (stack_put(st, callpc) == -1)
58			break;
59		frame = (u_int32_t *)(frame[FR_RFP]);
60	}
61#endif
62}
63
64void
65stack_save_td(struct stack *st, struct thread *td)
66{
67	u_int32_t *frame;
68
69	if (TD_IS_SWAPPED(td))
70		panic("stack_save_td: swapped");
71	if (TD_IS_RUNNING(td))
72		panic("stack_save_td: running");
73
74	/*
75	 * This register, the frame pointer, is incorrect for the ARM EABI
76	 * as it doesn't have a frame pointer, however it's value is not used
77	 * when building for EABI.
78	 */
79	frame = (u_int32_t *)td->td_pcb->un_32.pcb32_r11;
80	stack_zero(st);
81	stack_capture(st, frame);
82}
83
84void
85stack_save(struct stack *st)
86{
87	u_int32_t *frame;
88
89	frame = (u_int32_t *)__builtin_frame_address(0);
90	stack_zero(st);
91	stack_capture(st, frame);
92}
93