1 /* Native-dependent code for DragonFly/amd64.
2
3 Copyright (C) 2003-2013 Free Software Foundation, Inc.
4
5 This file is part of GDB.
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
19
20 #include "defs.h"
21 #include "inferior.h"
22 #include "regcache.h"
23 #include "target.h"
24 #include "gregset.h"
25
26 #include "gdb_assert.h"
27 #include <signal.h>
28 #include <stddef.h>
29 #include <sys/types.h>
30 #include <sys/procfs.h>
31 #include <sys/ptrace.h>
32 #include <sys/sysctl.h>
33 #include <machine/reg.h>
34
35 #include "fbsd-nat.h"
36 #include "amd64-tdep.h"
37 #include "amd64-nat.h"
38 #include "amd64bsd-nat.h"
39 #include "i386-nat.h"
40
41
42 /* Offset in `struct reg' where MEMBER is stored. */
43 #define REG_OFFSET(member) offsetof (struct reg, member)
44
45 /* At amd64dfly64_r_reg_offset[REGNUM] you'll find the offset in
46 `struct reg' location where the GDB register REGNUM is stored.
47 Unsupported registers are marked with `-1'. */
48 static int amd64dfly64_r_reg_offset[] =
49 {
50 REG_OFFSET (r_rax),
51 REG_OFFSET (r_rbx),
52 REG_OFFSET (r_rcx),
53 REG_OFFSET (r_rdx),
54 REG_OFFSET (r_rsi),
55 REG_OFFSET (r_rdi),
56 REG_OFFSET (r_rbp),
57 REG_OFFSET (r_rsp),
58 REG_OFFSET (r_r8),
59 REG_OFFSET (r_r9),
60 REG_OFFSET (r_r10),
61 REG_OFFSET (r_r11),
62 REG_OFFSET (r_r12),
63 REG_OFFSET (r_r13),
64 REG_OFFSET (r_r14),
65 REG_OFFSET (r_r15),
66 REG_OFFSET (r_rip),
67 REG_OFFSET (r_rflags),
68 REG_OFFSET (r_cs),
69 REG_OFFSET (r_ss),
70 -1,
71 -1,
72 -1,
73 -1
74 };
75
76
77 /* Mapping between the general-purpose registers in DragonFly/amd64
78 `struct reg' format and GDB's register cache layout for
79 DragonFly/i386.
80
81 Note that most DragonFly/amd64 registers are 64-bit, while the
82 DragonFly/i386 registers are all 32-bit, but since we're
83 little-endian we get away with that. */
84
85 /* From <machine/reg.h>. */
86 static int amd64dfly32_r_reg_offset[I386_NUM_GREGS] =
87 {
88 14 * 8, 13 * 8, /* %eax, %ecx */
89 12 * 8, 11 * 8, /* %edx, %ebx */
90 20 * 8, 10 * 8, /* %esp, %ebp */
91 9 * 8, 8 * 8, /* %esi, %edi */
92 17 * 8, 19 * 8, /* %eip, %eflags */
93 18 * 8, 21 * 8, /* %cs, %ss */
94 -1, -1, -1, -1 /* %ds, %es, %fs, %gs */
95 };
96
97
98 #ifdef DFLY_PCB_SUPPLY
99 /* Transfering the registers between GDB, inferiors and core files. */
100
101 /* Fill GDB's register array with the general-purpose register values
102 in *GREGSETP. */
103
104 void
supply_gregset(struct regcache * regcache,const gregset_t * gregsetp)105 supply_gregset (struct regcache *regcache, const gregset_t *gregsetp)
106 {
107 amd64_supply_native_gregset (regcache, gregsetp, -1);
108 }
109
110 /* Fill register REGNUM (if it is a general-purpose register) in
111 *GREGSETPS with the value in GDB's register array. If REGNUM is -1,
112 do this for all registers. */
113
114 void
fill_gregset(const struct regcache * regcache,gdb_gregset_t * gregsetp,int regnum)115 fill_gregset (const struct regcache *regcache, gdb_gregset_t *gregsetp, int regnum)
116 {
117 amd64_collect_native_gregset (regcache, gregsetp, regnum);
118 }
119
120 /* Fill GDB's register array with the floating-point register values
121 in *FPREGSETP. */
122
123 void
supply_fpregset(struct regcache * regcache,const fpregset_t * fpregsetp)124 supply_fpregset (struct regcache *regcache, const fpregset_t *fpregsetp)
125 {
126 amd64_supply_fxsave (regcache, -1, fpregsetp);
127 }
128
129 /* Fill register REGNUM (if it is a floating-point register) in
130 *FPREGSETP with the value in GDB's register array. If REGNUM is -1,
131 do this for all registers. */
132
133 void
fill_fpregset(const struct regcache * regcache,gdb_fpregset_t * fpregsetp,int regnum)134 fill_fpregset (const struct regcache *regcache, gdb_fpregset_t *fpregsetp, int regnum)
135 {
136 amd64_collect_fxsave (regcache, regnum, fpregsetp);
137 }
138
139 /* Support for debugging kernel virtual memory images. */
140
141 #include <sys/types.h>
142 #include <machine/pcb.h>
143 #include <osreldate.h>
144
145 #include "bsd-kvm.h"
146
147 static int
amd64dfly_supply_pcb(struct regcache * regcache,struct pcb * pcb)148 amd64dfly_supply_pcb (struct regcache *regcache, struct pcb *pcb)
149 {
150 /* The following is true for FreeBSD 5.2:
151
152 The pcb contains %rip, %rbx, %rsp, %rbp, %r12, %r13, %r14, %r15,
153 %ds, %es, %fs and %gs. This accounts for all callee-saved
154 registers specified by the psABI and then some. Here %esp
155 contains the stack pointer at the point just after the call to
156 cpu_switch(). From this information we reconstruct the register
157 state as it would like when we just returned from cpu_switch(). */
158
159 /* The stack pointer shouldn't be zero. */
160 if (pcb->pcb_rsp == 0)
161 return 0;
162
163 pcb->pcb_rsp += 8;
164 regcache_raw_supply (regcache, AMD64_RIP_REGNUM, &pcb->pcb_rip);
165 regcache_raw_supply (regcache, AMD64_RBX_REGNUM, &pcb->pcb_rbx);
166 regcache_raw_supply (regcache, AMD64_RSP_REGNUM, &pcb->pcb_rsp);
167 regcache_raw_supply (regcache, AMD64_RBP_REGNUM, &pcb->pcb_rbp);
168 regcache_raw_supply (regcache, 12, &pcb->pcb_r12);
169 regcache_raw_supply (regcache, 13, &pcb->pcb_r13);
170 regcache_raw_supply (regcache, 14, &pcb->pcb_r14);
171 regcache_raw_supply (regcache, 15, &pcb->pcb_r15);
172 #if (__FreeBSD_version < 800075) && (__FreeBSD_kernel_version < 800075)
173 /* struct pcb provides the pcb_ds/pcb_es/pcb_fs/pcb_gs fields only
174 up until __FreeBSD_version 800074: The removal of these fields
175 occurred on 2009-04-01 while the __FreeBSD_version number was
176 bumped to 800075 on 2009-04-06. So 800075 is the closest version
177 number where we should not try to access these fields. */
178 regcache_raw_supply (regcache, AMD64_DS_REGNUM, &pcb->pcb_ds);
179 regcache_raw_supply (regcache, AMD64_ES_REGNUM, &pcb->pcb_es);
180 regcache_raw_supply (regcache, AMD64_FS_REGNUM, &pcb->pcb_fs);
181 regcache_raw_supply (regcache, AMD64_GS_REGNUM, &pcb->pcb_gs);
182 #endif
183
184 return 1;
185 }
186 #endif /* DFLY_PCB_SUPPLY */
187
188
189 static void (*super_mourn_inferior) (struct target_ops *ops);
190
191 /* Work around vkernels not having PT_{GET,SET}DBREGS via ptrace(2) support. */
192 static int
is_vkernel(void)193 is_vkernel(void)
194 {
195 size_t len;
196 char buf[64];
197
198 len = sizeof(buf);
199 if (sysctlbyname("kern.vmm_guest", buf, &len, NULL, 0) < 0)
200 return 0;
201 if (strncmp("vkernel", buf, len) == 0)
202 return 1;
203 else
204 return 0;
205 }
206
207 static void
amd64dfly_mourn_inferior(struct target_ops * ops)208 amd64dfly_mourn_inferior (struct target_ops *ops)
209 {
210 #ifdef HAVE_PT_GETDBREGS
211 if (!is_vkernel())
212 i386_cleanup_dregs ();
213 #endif
214 super_mourn_inferior (ops);
215 }
216
217 /* Provide a prototype to silence -Wmissing-prototypes. */
218 void _initialize_amd64dfly_nat (void);
219
220 void
_initialize_amd64dfly_nat(void)221 _initialize_amd64dfly_nat (void)
222 {
223 struct target_ops *t;
224 int offset;
225
226 amd64_native_gregset32_reg_offset = amd64dfly32_r_reg_offset;
227 amd64_native_gregset64_reg_offset = amd64dfly64_r_reg_offset;
228
229 /* Add some extra features to the common *BSD/i386 target. */
230 t = amd64bsd_target ();
231
232 #ifdef HAVE_PT_GETDBREGS
233
234 if (!is_vkernel()) {
235 i386_use_watchpoints (t);
236
237 i386_dr_low.set_control = amd64bsd_dr_set_control;
238 i386_dr_low.set_addr = amd64bsd_dr_set_addr;
239 i386_dr_low.get_addr = amd64bsd_dr_get_addr;
240 i386_dr_low.get_status = amd64bsd_dr_get_status;
241 i386_dr_low.get_control = amd64bsd_dr_get_control;
242 i386_set_debug_register_length (8);
243 }
244
245 #endif /* HAVE_PT_GETDBREGS */
246
247 super_mourn_inferior = t->to_mourn_inferior;
248 t->to_mourn_inferior = amd64dfly_mourn_inferior;
249
250 t->to_pid_to_exec_file = fbsd_pid_to_exec_file;
251 t->to_find_memory_regions = fbsd_find_memory_regions;
252 t->to_make_corefile_notes = fbsd_make_corefile_notes;
253 add_target (t);
254
255 #ifdef DFLY_PCB_SUPPLY
256 /* Support debugging kernel virtual memory images. */
257 bsd_kvm_add_target (amd64dfly_supply_pcb);
258 #endif
259
260 /* To support the recognition of signal handlers, i386bsd-tdep.c
261 hardcodes some constants. Inclusion of this file means that we
262 are compiling a native debugger, which means that we can use the
263 system header files and sysctl(3) to get at the relevant
264 information. */
265
266 #define SC_REG_OFFSET amd64dfly_sc_reg_offset
267
268 /* We only check the program counter, stack pointer and frame
269 pointer since these members of `struct sigcontext' are essential
270 for providing backtraces. */
271
272 #define SC_RIP_OFFSET SC_REG_OFFSET[AMD64_RIP_REGNUM]
273 #define SC_RSP_OFFSET SC_REG_OFFSET[AMD64_RSP_REGNUM]
274 #define SC_RBP_OFFSET SC_REG_OFFSET[AMD64_RBP_REGNUM]
275
276 /* Override the default value for the offset of the program counter
277 in the sigcontext structure. */
278 offset = offsetof (struct sigcontext, sc_rip);
279
280 if (SC_RIP_OFFSET != offset)
281 {
282 warning (_("\
283 offsetof (struct sigcontext, sc_rip) yields %d instead of %d.\n\
284 Please report this to <bug-gdb@gnu.org>."),
285 offset, SC_RIP_OFFSET);
286 }
287
288 SC_RIP_OFFSET = offset;
289
290 /* Likewise for the stack pointer. */
291 offset = offsetof (struct sigcontext, sc_rsp);
292
293 if (SC_RSP_OFFSET != offset)
294 {
295 warning (_("\
296 offsetof (struct sigcontext, sc_rsp) yields %d instead of %d.\n\
297 Please report this to <bug-gdb@gnu.org>."),
298 offset, SC_RSP_OFFSET);
299 }
300
301 SC_RSP_OFFSET = offset;
302
303 /* And the frame pointer. */
304 offset = offsetof (struct sigcontext, sc_rbp);
305
306 if (SC_RBP_OFFSET != offset)
307 {
308 warning (_("\
309 offsetof (struct sigcontext, sc_rbp) yields %d instead of %d.\n\
310 Please report this to <bug-gdb@gnu.org>."),
311 offset, SC_RBP_OFFSET);
312 }
313
314 SC_RBP_OFFSET = offset;
315
316 /* DragonFly provides a kern.ps_strings sysctl that we can use to
317 locate the sigtramp. That way we can still recognize a sigtramp
318 if its location is changed in a new kernel. Of course this is
319 still based on the assumption that the sigtramp is placed
320 directly under the location where the program arguments and
321 environment can be found. */
322 {
323 int mib[2];
324 long ps_strings;
325 size_t len;
326
327 mib[0] = CTL_KERN;
328 mib[1] = KERN_PS_STRINGS;
329 len = sizeof (ps_strings);
330 if (sysctl (mib, 2, &ps_strings, &len, NULL, 0) == 0)
331 {
332 amd64dfly_sigtramp_start_addr = ps_strings - 32;
333 amd64dfly_sigtramp_end_addr = ps_strings;
334 }
335 }
336 }
337