1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2005 Antoine Brodin
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#include <sys/param.h>
30#include <sys/lock.h>
31#include <sys/mutex.h>
32#include <sys/proc.h>
33#include <sys/stack.h>
34#include <sys/systm.h>
35
36#include <vm/vm.h>
37#include <vm/pmap.h>
38#include <vm/vm_extern.h>
39
40#include <machine/db_machdep.h>
41#include <machine/pcb.h>
42#include <machine/spr.h>
43#include <machine/stack.h>
44#include <machine/trap.h>
45
46#ifdef __powerpc64__
47#define CALLOFFSET 8 /* Account for the TOC reload slot */
48#else
49#define CALLOFFSET 4
50#endif
51
52static void
53stack_capture(struct stack *st, vm_offset_t frame)
54{
55	vm_offset_t callpc;
56
57	stack_zero(st);
58	if (frame < PAGE_SIZE)
59		return;
60	while (1) {
61		frame = *(vm_offset_t *)frame;
62		if (frame < PAGE_SIZE)
63			break;
64
65	    #ifdef __powerpc64__
66		callpc = *(vm_offset_t *)(frame + 16) - 4;
67	    #else
68		callpc = *(vm_offset_t *)(frame + 4) - 4;
69	    #endif
70		if ((callpc & 3) || (callpc < 0x100))
71			break;
72
73		/*
74		 * Don't bother traversing trap-frames - there should
75		 * be enough info down to the frame to work out where
76		 * things are going wrong. Plus, prevents this shortened
77		 * version of code from accessing user-space frames
78		 */
79		if (callpc + CALLOFFSET == (vm_offset_t) &trapexit ||
80		    callpc + CALLOFFSET == (vm_offset_t) &asttrapexit)
81			break;
82
83		if (stack_put(st, callpc) == -1)
84			break;
85	}
86}
87
88int
89stack_save_td(struct stack *st, struct thread *td)
90{
91	vm_offset_t frame;
92
93	THREAD_LOCK_ASSERT(td, MA_OWNED);
94	KASSERT(!TD_IS_SWAPPED(td),
95	    ("stack_save_td: thread %p is swapped", td));
96
97	if (TD_IS_RUNNING(td))
98		return (EOPNOTSUPP);
99
100	frame = td->td_pcb->pcb_sp;
101	stack_capture(st, frame);
102	return (0);
103}
104
105void
106stack_save(struct stack *st)
107{
108	register_t frame;
109
110	frame = (register_t)__builtin_frame_address(0);
111	stack_capture(st, frame);
112}
113