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/param.h>
36#include <sys/systm.h>
37#include <sys/lock.h>
38#include <sys/mutex.h>
39#include <sys/proc.h>
40#include <sys/stack.h>
41
42#include <machine/vmparam.h>
43#include <machine/pcb.h>
44#include <machine/stack.h>
45
46static void
47stack_capture(struct thread *td, struct stack *st, struct unwind_state *frame)
48{
49
50	stack_zero(st);
51
52	while (1) {
53		if (!unwind_frame(td, frame))
54			break;
55		if (!INKERNEL((vm_offset_t)frame->pc))
56			break;
57		if (stack_put(st, frame->pc) == -1)
58			break;
59	}
60}
61
62int
63stack_save_td(struct stack *st, struct thread *td)
64{
65	struct unwind_state frame;
66
67	THREAD_LOCK_ASSERT(td, MA_OWNED);
68	KASSERT(!TD_IS_SWAPPED(td),
69	    ("stack_save_td: thread %p is swapped", td));
70
71	if (TD_IS_RUNNING(td))
72		return (EOPNOTSUPP);
73
74	frame.sp = td->td_pcb->pcb_sp;
75	frame.fp = td->td_pcb->pcb_s[0];
76	frame.pc = td->td_pcb->pcb_ra;
77
78	stack_capture(td, st, &frame);
79	return (0);
80}
81
82void
83stack_save(struct stack *st)
84{
85	struct unwind_state frame;
86	uintptr_t sp;
87
88	__asm __volatile("mv %0, sp" : "=&r" (sp));
89
90	frame.sp = sp;
91	frame.fp = (uintptr_t)__builtin_frame_address(0);
92	frame.pc = (uintptr_t)stack_save;
93
94	stack_capture(curthread, st, &frame);
95}
96