1 /* Fetch live process registers from TID.
2 Copyright (C) 2015 Oracle, In
3 This file is part of elfutils.
4
5 This file is free software; you can redistribute it and/or modify
6 it under the terms of either
7
8 * the GNU Lesser General Public License as published by the Free
9 Software Foundation; either version 3 of the License, or (at
10 your option) any later version
11
12 or
13
14 * the GNU General Public License as published by the Free
15 Software Foundation; either version 2 of the License, or (at
16 your option) any later version
17
18 or both in parallel, as here.
19
20 elfutils is distributed in the hope that it will be useful, but
21 WITHOUT ANY WARRANTY; without even the implied warranty of
22 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
23 General Public License for more details.
24
25 You should have received copies of the GNU General Public License and
26 the GNU Lesser General Public License along with this program. If
27 not, see <http://www.gnu.org/licenses/>. */
28
29 #ifdef HAVE_CONFIG_H
30 # include <config.h>
31 #endif
32
33 #include "system.h"
34 #include <stdlib.h>
35 #ifdef __sparc__
36 # include <asm/ptrace.h>
37 # include <sys/ptrace.h>
38 #endif
39
40 #define BACKEND sparc_
41 #include "libebl_CPU.h"
42
43 bool
EBLHOOK(set_initial_registers_tid)44 EBLHOOK (set_initial_registers_tid) (pid_t tid __attribute__ ((unused)),
45 ebl_tid_registers_t *setfunc __attribute__ ((unused)),
46 void *arg __attribute__ ((unused)))
47 {
48 #if !defined(__sparc__) || !defined( __arch64__)
49 return false;
50 #else /* __sparc__ */
51
52
53 /* The pt_regs structure filled in by PTRACE_GETREGS provides the
54 PC, the global registers and the output registers. Note how the
55 %g0 register is not explicitly provided in the structure (it's
56 value is always 0) and the resulting weird packing in the u_regs
57 array: the last element is not used. */
58
59 struct pt_regs regs;
60 if (ptrace (PTRACE_GETREGS, tid, ®s, 0) == -1)
61 return false;
62
63 /* PC: no DWARF number */
64 if (!setfunc (-1, 1, (Dwarf_Word *) ®s.tpc, arg))
65 return false;
66
67 /* Global registers: DWARF 0 .. 7 */
68 Dwarf_Word zero = 0;
69 if (!setfunc (0, 1, &zero, arg))
70 return false;
71 if (!setfunc (1, 7, (Dwarf_Word *) ®s.u_regs[0], arg))
72 return false;
73
74 /* Output registers: DWARF 8 .. 15 */
75 if (!setfunc (8, 8, (Dwarf_Word *) ®s.u_regs[7], arg))
76 return false;
77
78 /* Local and input registers must be read from the stack. They are
79 saved in the previous stack frame. The stack pointer is %o6,
80 read above. */
81
82 Dwarf_Word locals_outs[16];
83 Dwarf_Word sp = regs.u_regs[13];
84
85 if (sp & 1)
86 {
87 /* Registers are 64 bits, and we need to apply the 2047 stack
88 bias in order to get the real stack pointer. */
89
90 sp += 2047;
91
92 for (unsigned i = 0; i < 16; i++)
93 {
94 locals_outs[i] = ptrace (PTRACE_PEEKDATA, tid,
95 (void *) (uintptr_t) (sp + (i * 8)),
96 NULL);
97 if (errno != 0)
98 return false;
99 }
100 }
101 else
102 {
103 /* Registers are 32 bits. */
104
105 for (unsigned i = 0; i < 8; i++)
106 {
107 Dwarf_Word tuple = ptrace (PTRACE_PEEKDATA, tid,
108 (void *) (uintptr_t) (sp + (i * 8)),
109 NULL);
110 if (errno != 0)
111 return false;
112
113 locals_outs[2*i] = (tuple >> 32) & 0xffffffff;
114 locals_outs[2*i+1] = tuple & 0xffffffff;
115 }
116 }
117
118
119 /* Local registers: DWARF 16 .. 23 */
120 if (!setfunc (16, 8, &locals_outs[0], arg))
121 return false;
122
123 /* Input registers: DWARF 24 .. 31 */
124 if (!setfunc (24, 8, &locals_outs[8], arg))
125 return false;
126
127 return true;
128 #endif
129 }
130