1 /*
2 * Copyright (c) 2004 Marcel Moolenaar
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 *
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29
30 #include <sys/param.h>
31 #include <sys/proc.h>
32 #include <sys/sysctl.h>
33 #include <sys/user.h>
34 #include <err.h>
35 #include <fcntl.h>
36 #include <kvm.h>
37
38 #include <defs.h>
39 #include <readline/readline.h>
40 #include <readline/tilde.h>
41 #include <command.h>
42 #include <exec.h>
43 #include <frame-unwind.h>
44 #include <gdb.h>
45 #include <gdbcore.h>
46 #include <gdbthread.h>
47 #include <inferior.h>
48 #include <language.h>
49 #include <regcache.h>
50 #include <solib.h>
51 #include <target.h>
52 #include <ui-out.h>
53
54 #include "kgdb.h"
55
56 #ifdef CROSS_DEBUGGER
57 /*
58 * We suppress the call to add_target() of core_ops in corelow.c because if
59 * there are multiple core_stratum targets, the find_core_target() function
60 * won't know which one to return and returns none. We need it to return
61 * our target. We only have to do that when we're building a cross-debugger
62 * because fbsd-threads.c is part of a native debugger and it too defines
63 * coreops_suppress_target with 1 as the initializer.
64 */
65 int coreops_suppress_target = 1;
66 #endif
67
68 static CORE_ADDR stoppcbs;
69
70 static void kgdb_core_cleanup(void *);
71
72 static char *vmcore;
73 static struct target_ops kgdb_trgt_ops;
74
75 kvm_t *kvm;
76 static char kvm_err[_POSIX2_LINE_MAX];
77
78 #define KERNOFF (kgdb_kernbase ())
79 #define PINKERNEL(x) ((x) >= KERNOFF)
80
81 static int
kgdb_resolve_symbol(const char * name,kvaddr_t * kva)82 kgdb_resolve_symbol(const char *name, kvaddr_t *kva)
83 {
84 struct minimal_symbol *ms;
85
86 ms = lookup_minimal_symbol (name, NULL, NULL);
87 if (ms == NULL)
88 return (1);
89
90 *kva = SYMBOL_VALUE_ADDRESS (ms);
91 return (0);
92 }
93
94 static CORE_ADDR
kgdb_kernbase(void)95 kgdb_kernbase (void)
96 {
97 static CORE_ADDR kernbase;
98 struct minimal_symbol *sym;
99
100 if (kernbase == 0) {
101 sym = lookup_minimal_symbol ("kernbase", NULL, NULL);
102 if (sym == NULL) {
103 kernbase = KERNBASE;
104 } else {
105 kernbase = SYMBOL_VALUE_ADDRESS (sym);
106 }
107 }
108 return kernbase;
109 }
110
111 static void
kgdb_trgt_open(char * filename,int from_tty)112 kgdb_trgt_open(char *filename, int from_tty)
113 {
114 struct cleanup *old_chain;
115 struct thread_info *ti;
116 struct kthr *kt;
117 kvm_t *nkvm;
118 char *temp;
119 int ontop;
120
121 target_preopen (from_tty);
122 if (!filename)
123 error ("No vmcore file specified.");
124 if (!exec_bfd)
125 error ("Can't open a vmcore without a kernel");
126
127 filename = tilde_expand (filename);
128 if (filename[0] != '/') {
129 temp = concat (current_directory, "/", filename, NULL);
130 xfree(filename);
131 filename = temp;
132 }
133
134 old_chain = make_cleanup (xfree, filename);
135
136 nkvm = kvm_open2(bfd_get_filename(exec_bfd), filename,
137 write_files ? O_RDWR : O_RDONLY, kvm_err, kgdb_resolve_symbol);
138 if (nkvm == NULL)
139 error ("Failed to open vmcore: %s", kvm_err);
140
141 /* Don't free the filename now and close any previous vmcore. */
142 discard_cleanups(old_chain);
143 unpush_target(&kgdb_trgt_ops);
144
145 kvm = nkvm;
146 vmcore = filename;
147 old_chain = make_cleanup(kgdb_core_cleanup, NULL);
148
149 ontop = !push_target (&kgdb_trgt_ops);
150 discard_cleanups (old_chain);
151
152 kgdb_dmesg();
153
154 init_thread_list();
155 kt = kgdb_thr_init();
156 while (kt != NULL) {
157 ti = add_thread(pid_to_ptid(kt->tid));
158 kt = kgdb_thr_next(kt);
159 }
160 if (curkthr != 0)
161 inferior_ptid = pid_to_ptid(curkthr->tid);
162
163 if (ontop) {
164 /* XXX: fetch registers? */
165 kld_init();
166 flush_cached_frames();
167 select_frame (get_current_frame());
168 print_stack_frame(get_selected_frame(),
169 frame_relative_level(get_selected_frame()), 1);
170 } else
171 warning(
172 "you won't be able to access this vmcore until you terminate\n\
173 your %s; do ``info files''", target_longname);
174 }
175
176 static void
kgdb_trgt_close(int quitting)177 kgdb_trgt_close(int quitting)
178 {
179
180 if (kvm != NULL) {
181 inferior_ptid = null_ptid;
182 CLEAR_SOLIB();
183 if (kvm_close(kvm) != 0)
184 warning("cannot close \"%s\": %s", vmcore,
185 kvm_geterr(kvm));
186 kvm = NULL;
187 xfree(vmcore);
188 vmcore = NULL;
189 if (kgdb_trgt_ops.to_sections) {
190 xfree(kgdb_trgt_ops.to_sections);
191 kgdb_trgt_ops.to_sections = NULL;
192 kgdb_trgt_ops.to_sections_end = NULL;
193 }
194 }
195 }
196
197 static void
kgdb_core_cleanup(void * arg)198 kgdb_core_cleanup(void *arg)
199 {
200
201 kgdb_trgt_close(0);
202 }
203
204 static void
kgdb_trgt_detach(char * args,int from_tty)205 kgdb_trgt_detach(char *args, int from_tty)
206 {
207
208 if (args)
209 error ("Too many arguments");
210 unpush_target(&kgdb_trgt_ops);
211 reinit_frame_cache();
212 if (from_tty)
213 printf_filtered("No vmcore file now.\n");
214 }
215
216 static char *
kgdb_trgt_extra_thread_info(struct thread_info * ti)217 kgdb_trgt_extra_thread_info(struct thread_info *ti)
218 {
219
220 return (kgdb_thr_extra_thread_info(ptid_get_pid(ti->ptid)));
221 }
222
223 static void
kgdb_trgt_files_info(struct target_ops * target)224 kgdb_trgt_files_info(struct target_ops *target)
225 {
226
227 printf_filtered ("\t`%s', ", vmcore);
228 wrap_here (" ");
229 printf_filtered ("file type %s.\n", "FreeBSD kernel vmcore");
230 }
231
232 static void
kgdb_trgt_find_new_threads(void)233 kgdb_trgt_find_new_threads(void)
234 {
235 struct target_ops *tb;
236
237 if (kvm != NULL)
238 return;
239
240 tb = find_target_beneath(&kgdb_trgt_ops);
241 if (tb->to_find_new_threads != NULL)
242 tb->to_find_new_threads();
243 }
244
245 static char *
kgdb_trgt_pid_to_str(ptid_t ptid)246 kgdb_trgt_pid_to_str(ptid_t ptid)
247 {
248 static char buf[33];
249
250 snprintf(buf, sizeof(buf), "Thread %d", ptid_get_pid(ptid));
251 return (buf);
252 }
253
254 static int
kgdb_trgt_thread_alive(ptid_t ptid)255 kgdb_trgt_thread_alive(ptid_t ptid)
256 {
257 return (kgdb_thr_lookup_tid(ptid_get_pid(ptid)) != NULL);
258 }
259
260 static int
kgdb_trgt_xfer_memory(CORE_ADDR memaddr,char * myaddr,int len,int write,struct mem_attrib * attrib,struct target_ops * target)261 kgdb_trgt_xfer_memory(CORE_ADDR memaddr, char *myaddr, int len, int write,
262 struct mem_attrib *attrib, struct target_ops *target)
263 {
264 struct target_ops *tb;
265
266 if (kvm != NULL) {
267 if (len == 0)
268 return (0);
269 if (!write)
270 return (kvm_read2(kvm, memaddr, myaddr, len));
271 else
272 return (kvm_write(kvm, memaddr, myaddr, len));
273 }
274 tb = find_target_beneath(target);
275 return (tb->to_xfer_memory(memaddr, myaddr, len, write, attrib, tb));
276 }
277
278 static int
kgdb_trgt_ignore_breakpoints(CORE_ADDR addr,char * contents)279 kgdb_trgt_ignore_breakpoints(CORE_ADDR addr, char *contents)
280 {
281
282 return 0;
283 }
284
285 static void
kgdb_switch_to_thread(int tid)286 kgdb_switch_to_thread(int tid)
287 {
288 char buf[16];
289 int thread_id;
290
291 thread_id = pid_to_thread_id(pid_to_ptid(tid));
292 if (thread_id == 0)
293 error ("invalid tid");
294 snprintf(buf, sizeof(buf), "%d", thread_id);
295 gdb_thread_select(uiout, buf);
296 }
297
298 static void
kgdb_set_proc_cmd(char * arg,int from_tty)299 kgdb_set_proc_cmd (char *arg, int from_tty)
300 {
301 CORE_ADDR addr;
302 struct kthr *thr;
303
304 if (!arg)
305 error_no_arg ("proc address for the new context");
306
307 if (kvm == NULL)
308 error ("only supported for core file target");
309
310 addr = (CORE_ADDR) parse_and_eval_address (arg);
311
312 if (!PINKERNEL (addr)) {
313 thr = kgdb_thr_lookup_pid((int)addr);
314 if (thr == NULL)
315 error ("invalid pid");
316 } else {
317 thr = kgdb_thr_lookup_paddr(addr);
318 if (thr == NULL)
319 error("invalid proc address");
320 }
321 kgdb_switch_to_thread(thr->tid);
322 }
323
324 static void
kgdb_set_tid_cmd(char * arg,int from_tty)325 kgdb_set_tid_cmd (char *arg, int from_tty)
326 {
327 CORE_ADDR addr;
328 struct kthr *thr;
329
330 if (!arg)
331 error_no_arg ("TID or thread address for the new context");
332
333 addr = (CORE_ADDR) parse_and_eval_address (arg);
334
335 if (kvm != NULL && PINKERNEL (addr)) {
336 thr = kgdb_thr_lookup_taddr(addr);
337 if (thr == NULL)
338 error("invalid thread address");
339 addr = thr->tid;
340 }
341 kgdb_switch_to_thread(addr);
342 }
343
344 int fbsdcoreops_suppress_target = 1;
345
346 void
initialize_kgdb_target(void)347 initialize_kgdb_target(void)
348 {
349
350 kgdb_trgt_ops.to_magic = OPS_MAGIC;
351 kgdb_trgt_ops.to_shortname = "kernel";
352 kgdb_trgt_ops.to_longname = "kernel core dump file";
353 kgdb_trgt_ops.to_doc =
354 "Use a vmcore file as a target. Specify the filename of the vmcore file.";
355 kgdb_trgt_ops.to_stratum = core_stratum;
356 kgdb_trgt_ops.to_has_memory = 1;
357 kgdb_trgt_ops.to_has_registers = 1;
358 kgdb_trgt_ops.to_has_stack = 1;
359
360 kgdb_trgt_ops.to_open = kgdb_trgt_open;
361 kgdb_trgt_ops.to_close = kgdb_trgt_close;
362 kgdb_trgt_ops.to_attach = find_default_attach;
363 kgdb_trgt_ops.to_detach = kgdb_trgt_detach;
364 kgdb_trgt_ops.to_extra_thread_info = kgdb_trgt_extra_thread_info;
365 kgdb_trgt_ops.to_fetch_registers = kgdb_trgt_fetch_registers;
366 kgdb_trgt_ops.to_files_info = kgdb_trgt_files_info;
367 kgdb_trgt_ops.to_find_new_threads = kgdb_trgt_find_new_threads;
368 kgdb_trgt_ops.to_pid_to_str = kgdb_trgt_pid_to_str;
369 kgdb_trgt_ops.to_store_registers = kgdb_trgt_store_registers;
370 kgdb_trgt_ops.to_thread_alive = kgdb_trgt_thread_alive;
371 kgdb_trgt_ops.to_xfer_memory = kgdb_trgt_xfer_memory;
372 kgdb_trgt_ops.to_insert_breakpoint = kgdb_trgt_ignore_breakpoints;
373 kgdb_trgt_ops.to_remove_breakpoint = kgdb_trgt_ignore_breakpoints;
374
375 add_target(&kgdb_trgt_ops);
376
377 add_com ("proc", class_obscure, kgdb_set_proc_cmd,
378 "Set current process context");
379 add_com ("tid", class_obscure, kgdb_set_tid_cmd,
380 "Set current thread context");
381 }
382
383 CORE_ADDR
kgdb_trgt_stop_pcb(u_int cpuid,u_int pcbsz)384 kgdb_trgt_stop_pcb(u_int cpuid, u_int pcbsz)
385 {
386 static int once = 0;
387
388 if (stoppcbs == 0 && !once) {
389 once = 1;
390 stoppcbs = kgdb_lookup("stoppcbs");
391 }
392 if (stoppcbs == 0)
393 return 0;
394
395 return (stoppcbs + pcbsz * cpuid);
396 }
397