xref: /freebsd/sys/powerpc/powerpc/stack_machdep.c (revision 4f52dfbb)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 #include <sys/proc.h>
34 #include <sys/stack.h>
35 #include <sys/systm.h>
36 
37 #include <vm/vm.h>
38 #include <vm/pmap.h>
39 #include <vm/vm_extern.h>
40 
41 #include <machine/db_machdep.h>
42 #include <machine/pcb.h>
43 #include <machine/spr.h>
44 #include <machine/stack.h>
45 #include <machine/trap.h>
46 
47 #ifdef __powerpc64__
48 #define CALLOFFSET 8 /* Account for the TOC reload slot */
49 #else
50 #define CALLOFFSET 4
51 #endif
52 
53 static void
54 stack_capture(struct stack *st, vm_offset_t frame)
55 {
56 	vm_offset_t callpc;
57 
58 	stack_zero(st);
59 	if (frame < PAGE_SIZE)
60 		return;
61 	while (1) {
62 		frame = *(vm_offset_t *)frame;
63 		if (frame < PAGE_SIZE)
64 			break;
65 
66 	    #ifdef __powerpc64__
67 		callpc = *(vm_offset_t *)(frame + 16) - 4;
68 	    #else
69 		callpc = *(vm_offset_t *)(frame + 4) - 4;
70 	    #endif
71 		if ((callpc & 3) || (callpc < 0x100))
72 			break;
73 
74 		/*
75 		 * Don't bother traversing trap-frames - there should
76 		 * be enough info down to the frame to work out where
77 		 * things are going wrong. Plus, prevents this shortened
78 		 * version of code from accessing user-space frames
79 		 */
80 		if (callpc + CALLOFFSET == (vm_offset_t) &trapexit ||
81 		    callpc + CALLOFFSET == (vm_offset_t) &asttrapexit)
82 			break;
83 
84 		if (stack_put(st, callpc) == -1)
85 			break;
86 	}
87 }
88 
89 void
90 stack_save_td(struct stack *st, struct thread *td)
91 {
92 	vm_offset_t frame;
93 
94 	if (TD_IS_SWAPPED(td))
95 		panic("stack_save_td: swapped");
96 	if (TD_IS_RUNNING(td))
97 		panic("stack_save_td: running");
98 
99 	frame = td->td_pcb->pcb_sp;
100 	stack_capture(st, frame);
101 }
102 
103 int
104 stack_save_td_running(struct stack *st, struct thread *td)
105 {
106 
107 	return (EOPNOTSUPP);
108 }
109 
110 void
111 stack_save(struct stack *st)
112 {
113 	register_t frame;
114 
115 	frame = (register_t)__builtin_frame_address(0);
116 	stack_capture(st, frame);
117 }
118