1/*-
2 * Copyright (c) 2016 Ruslan Bukin <br@bsdpad.com>
3 * All rights reserved.
4 *
5 * Portions of this software were developed by SRI International and the
6 * University of Cambridge Computer Laboratory under DARPA/AFRL contract
7 * FA8750-10-C-0237 ("CTSRD"), as part of the DARPA CRASH research programme.
8 *
9 * Portions of this software were developed by the University of Cambridge
10 * Computer Laboratory as part of the CTSRD Project, with support from the
11 * UK Higher Education Innovation Fund (HEIF).
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 *    notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 *    notice, this list of conditions and the following disclaimer in the
20 *    documentation and/or other materials provided with the distribution.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35#include <sys/cdefs.h>
36__FBSDID("$FreeBSD$");
37
38#include <sys/param.h>
39#include <sys/systm.h>
40#include <sys/lock.h>
41#include <sys/mutex.h>
42#include <sys/proc.h>
43#include <sys/stack.h>
44
45#include <machine/vmparam.h>
46#include <machine/pcb.h>
47#include <machine/stack.h>
48
49static void
50stack_capture(struct thread *td, struct stack *st, struct unwind_state *frame)
51{
52
53	stack_zero(st);
54
55	while (1) {
56		if (!unwind_frame(td, frame))
57			break;
58		if (!INKERNEL((vm_offset_t)frame->pc))
59			break;
60		if (stack_put(st, frame->pc) == -1)
61			break;
62	}
63}
64
65int
66stack_save_td(struct stack *st, struct thread *td)
67{
68	struct unwind_state frame;
69
70	THREAD_LOCK_ASSERT(td, MA_OWNED);
71	KASSERT(!TD_IS_SWAPPED(td),
72	    ("stack_save_td: thread %p is swapped", td));
73
74	if (TD_IS_RUNNING(td))
75		return (EOPNOTSUPP);
76
77	frame.sp = td->td_pcb->pcb_sp;
78	frame.fp = td->td_pcb->pcb_s[0];
79	frame.pc = td->td_pcb->pcb_ra;
80
81	stack_capture(td, st, &frame);
82	return (0);
83}
84
85void
86stack_save(struct stack *st)
87{
88	struct unwind_state frame;
89	uintptr_t sp;
90
91	__asm __volatile("mv %0, sp" : "=&r" (sp));
92
93	frame.sp = sp;
94	frame.fp = (uintptr_t)__builtin_frame_address(0);
95	frame.pc = (uintptr_t)stack_save;
96
97	stack_capture(curthread, st, &frame);
98}
99