stack_machdep.c revision 174195 
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: head/sys/powerpc/powerpc/stack_machdep.c 174195 2007-12-02 20:40:35Z rwatson $");
29
30#include <sys/param.h>
31#include <sys/proc.h>
32#include <sys/stack.h>
33#include <sys/systm.h>
34
35#include <vm/vm.h>
36#include <vm/pmap.h>
37#include <vm/vm_extern.h>
38
39#include <machine/db_machdep.h>
40#include <machine/pcb.h>
41#include <machine/spr.h>
42#include <machine/stack.h>
43#include <machine/trap.h>
44
45static void
46stack_capture(struct stack *st, register_t frame)
47{
48	vm_offset_t callpc;
49
50	stack_zero(st);
51	if (frame < PAGE_SIZE)
52		return;
53	while (1) {
54		frame = *(register_t *)frame;
55		if (frame < PAGE_SIZE)
56			break;
57		callpc = *(vm_offset_t *)(frame + 4) - 4;
58		if ((callpc & 3) || (callpc < 0x100))
59			break;
60
61		/*
62		 * Don't bother traversing trap-frames - there should
63		 * be enough info down to the frame to work out where
64		 * things are going wrong. Plus, prevents this shortened
65		 * version of code from accessing user-space frames
66		 */
67		if (callpc + 4 == (register_t) &trapexit ||
68		    callpc + 4 == (register_t) &asttrapexit)
69			break;
70
71		if (stack_put(st, callpc) == -1)
72			break;
73	}
74}
75
76void
77stack_save_td(struct stack *st, struct thread *td)
78{
79	register_t frame;
80
81	if (TD_IS_SWAPPED(td))
82		panic("stack_save_td: swapped");
83	if (TD_IS_RUNNING(td))
84		panic("stack_save_td: running");
85
86	frame = td->td_pcb->pcb_sp;
87	stack_capture(st, frame);
88}
89
90void
91stack_save(struct stack *st)
92{
93	register_t frame;
94
95	frame = (register_t)__builtin_frame_address(1);
96	stack_capture(st, frame);
97}
98