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: releng/9.1/sys/mips/mips/stack_machdep.c 209500 2010-06-24 08:08:43Z jchandra $");
29
30 #include <sys/types.h>
31 #include <sys/systm.h>
32 #include <sys/param.h>
33 #include <sys/proc.h>
34 #include <sys/stack.h>
35
36 #include <machine/mips_opcode.h>
37
38 #include <machine/param.h>
39 #include <machine/pcb.h>
40 #include <machine/regnum.h>
41
42 static u_register_t
43 stack_register_fetch(u_register_t sp, u_register_t stack_pos)
44 {
45 u_register_t * stack =
46 ((u_register_t *)(intptr_t)sp + (size_t)stack_pos/sizeof(u_register_t));
47
48 return *stack;
49 }
50
51 static void
52 stack_capture(struct stack *st, u_register_t pc, u_register_t sp)
53 {
54 u_register_t ra = 0, i, stacksize;
55 short ra_stack_pos = 0;
56 InstFmt insn;
57
58 stack_zero(st);
59
60 for (;;) {
61 stacksize = 0;
62 if (pc <= (u_register_t)(intptr_t)btext)
63 break;
64 for (i = pc; i >= (u_register_t)(intptr_t)btext; i -= sizeof (insn)) {
65 bcopy((void *)(intptr_t)i, &insn, sizeof insn);
66 switch (insn.IType.op) {
67 case OP_ADDI:
68 case OP_ADDIU:
69 case OP_DADDI:
70 case OP_DADDIU:
71 if (insn.IType.rs != SP || insn.IType.rt != SP)
72 break;
73 stacksize = -(short)insn.IType.imm;
74 break;
75
76 case OP_SW:
77 case OP_SD:
78 if (insn.IType.rs != SP || insn.IType.rt != RA)
79 break;
80 ra_stack_pos = (short)insn.IType.imm;
81 break;
82 default:
83 break;
84 }
85
86 if (stacksize)
87 break;
88 }
89
90 if (stack_put(st, pc) == -1)
91 break;
92
93 for (i = pc; !ra; i += sizeof (insn)) {
94 bcopy((void *)(intptr_t)i, &insn, sizeof insn);
95
96 switch (insn.IType.op) {
97 case OP_SPECIAL:
98 if((insn.RType.func == OP_JR))
99 {
100 if (ra >= (u_register_t)(intptr_t)btext)
101 break;
102 if (insn.RType.rs != RA)
103 break;
104 ra = stack_register_fetch(sp,
105 ra_stack_pos);
106 if (!ra)
107 goto done;
108 ra -= 8;
109 }
110 break;
111 default:
112 break;
113 }
114 /* eret */
115 if (insn.word == 0x42000018)
116 goto done;
117 }
118
119 if (pc == ra && stacksize == 0)
120 break;
121
122 sp += stacksize;
123 pc = ra;
124 ra = 0;
125 }
126 done:
127 return;
128 }
129
130 void
131 stack_save_td(struct stack *st, struct thread *td)
132 {
133 u_register_t pc, sp;
134
135 if (TD_IS_SWAPPED(td))
136 panic("stack_save_td: swapped");
137 if (TD_IS_RUNNING(td))
138 panic("stack_save_td: running");
139
140 pc = td->td_pcb->pcb_regs.pc;
141 sp = td->td_pcb->pcb_regs.sp;
142 stack_capture(st, pc, sp);
143 }
144
145 void
146 stack_save(struct stack *st)
147 {
148 u_register_t pc, sp;
149
150 if (curthread == NULL)
151 panic("stack_save: curthread == NULL)");
152
153 pc = curthread->td_pcb->pcb_regs.pc;
154 sp = curthread->td_pcb->pcb_regs.sp;
155 stack_capture(st, pc, sp);
156 }
Cache object: 138ed1ad351f14d224f87b97f4dde6f6
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