xref: /dragonfly/gnu/usr.bin/gdb/kgdb/trgt.c (revision 91dc43dd)
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  * $FreeBSD: src/gnu/usr.bin/gdb/kgdb/trgt.c,v 1.12 2008/05/01 20:36:48 jhb Exp $
27  */
28 
29 #include <sys/cdefs.h>
30 
31 #include <sys/param.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 #include <observer.h>
54 #include <arch-utils.h>
55 
56 #include "kgdb.h"
57 
58 static void	kgdb_core_cleanup(void *);
59 
60 static char *vmcore;
61 static struct target_ops kgdb_trgt_ops;
62 
63 kvm_t *kvm;
64 static char kvm_err[_POSIX2_LINE_MAX];
65 
66 #define	KERNOFF		(kgdb_kernbase ())
67 #define	INKERNEL(x)	((x) >= KERNOFF)
68 
69 static CORE_ADDR
70 kgdb_kernbase (void)
71 {
72 	static CORE_ADDR kernbase;
73 	struct minimal_symbol *sym;
74 
75 	if (kernbase == 0) {
76 		sym = lookup_minimal_symbol ("kernbase", NULL, NULL);
77 		if (sym == NULL) {
78 			kernbase = KERNBASE;
79 		} else {
80 			kernbase = SYMBOL_VALUE_ADDRESS (sym);
81 		}
82 	}
83 	return kernbase;
84 }
85 
86 static void
87 kgdb_trgt_open(char *filename, int from_tty)
88 {
89 	struct cleanup *old_chain;
90 	struct kthr *kt;
91 	struct inferior *inf8;
92 	struct program_space *pspace;
93 	kvm_t *nkvm;
94 	char *temp;
95 	int first_inferior = 1;
96 	struct gdbarch_info info;
97 	struct gdbarch *kgdbarch;
98 
99 	target_preopen (from_tty);
100 	if (!filename)
101 		error ("No vmcore file specified.");
102 	if (!exec_bfd)
103 		error ("Can't open a vmcore without a kernel");
104 
105 	filename = tilde_expand (filename);
106 	if (filename[0] != '/') {
107 		temp = concat (current_directory, "/", filename, NULL);
108 		xfree(filename);
109 		filename = temp;
110 	}
111 
112 	old_chain = make_cleanup (xfree, filename);
113 
114 	nkvm = kvm_openfiles(bfd_get_filename(exec_bfd), filename, NULL,
115 	    write_files ? O_RDWR : O_RDONLY, kvm_err);
116 	if (nkvm == NULL)
117 		error ("Failed to open vmcore: %s", kvm_err);
118 
119 	/* Don't free the filename now and close any previous vmcore. */
120 	discard_cleanups(old_chain);
121 	unpush_target(&kgdb_trgt_ops);
122 
123 	kvm = nkvm;
124 	vmcore = filename;
125 	old_chain = make_cleanup(kgdb_core_cleanup, NULL);
126 
127 	push_target (&kgdb_trgt_ops);
128 	discard_cleanups (old_chain);
129 
130 	kgdb_dmesg();
131 
132 	gdbarch_info_init (&info);
133 #if defined (__i386__)
134 	info.bfd_arch_info = bfd_scan_arch ("i386");
135 #elif defined (__x86_64__)
136 	info.bfd_arch_info = bfd_scan_arch ("i386:x86-64");
137 #else
138 #error platform not recognized
139 #endif
140 	info.byte_order = BFD_ENDIAN_LITTLE;
141 	gdbarch_info_fill (&info);
142 	kgdbarch = gdbarch_find_by_info (info);
143 
144 	init_thread_list();
145 	kt = kgdb_thr_init();
146 	while (kt != NULL) {
147 		if (!in_inferior_list(kt->pid)) {
148                      if (first_inferior) {
149                        first_inferior = 0;
150                        inf8 = current_inferior();
151                        inf8->pid = kt->pid;
152                        inf8->attach_flag = 1;
153                        inferior_appeared (inf8, kt->pid);
154                        pspace = current_program_space;
155                        pspace->ebfd = 0;
156                        pspace->ebfd_mtime = 0;
157                      } else {
158                        inf8 = add_inferior(kt->pid);
159                        inf8->attach_flag = 0;
160                        pspace = add_program_space(new_address_space());
161                        pspace->symfile_object_file = symfile_objfile;
162                        pspace->objfiles = object_files;
163                      }
164                      inf8->pspace = pspace;
165                      inf8->aspace = pspace->aspace;
166                      inf8->fake_pid_p = 0;
167                      inf8->gdbarch = kgdbarch;
168                 }
169 		add_thread(ptid_build(kt->pid, kt->lwpid, kt->tid));
170 		kt = kgdb_thr_next(kt);
171 	}
172 	if (curkthr != 0)
173 		inferior_ptid = ptid_build(curkthr->pid, curkthr->lwpid,
174 			curkthr->tid);
175 
176 	frame_unwind_prepend_unwinder(kgdbarch, &kgdb_trgt_trapframe_unwind);
177 
178 	kld_init(kgdbarch);
179 	reinit_frame_cache();
180 	select_frame (get_current_frame());
181 	print_stack_frame(get_selected_frame(NULL), 0, SRC_AND_LOC);
182 }
183 
184 static void
185 kgdb_trgt_close(int quitting)
186 {
187 
188 	if (kvm != NULL) {
189 		inferior_ptid = null_ptid;
190 		clear_solib();
191 		if (kvm_close(kvm) != 0)
192 			warning("cannot close \"%s\": %s", vmcore,
193 			    kvm_geterr(kvm));
194 		kvm = NULL;
195 		xfree(vmcore);
196 		vmcore = NULL;
197 	}
198 }
199 
200 static void
201 kgdb_core_cleanup(void *arg)
202 {
203 
204 	kgdb_trgt_close(0);
205 }
206 
207 static void
208 kgdb_trgt_detach(struct target_ops *target, char *args, int from_tty)
209 {
210 
211 	if (args)
212 		error ("Too many arguments");
213 	unpush_target(target);
214 	reinit_frame_cache();
215 	if (from_tty)
216 		printf_filtered("No vmcore file now.\n");
217 }
218 
219 static char *
220 kgdb_trgt_extra_thread_info(struct thread_info *ti)
221 {
222 
223 	return (kgdb_thr_extra_thread_info(ptid_get_tid(ti->ptid)));
224 }
225 
226 static void
227 kgdb_trgt_files_info(struct target_ops *target)
228 {
229 
230 	printf_filtered ("\t`%s', ", vmcore);
231 	wrap_here ("        ");
232 	printf_filtered ("file type %s.\n", "DragonFly kernel vmcore");
233 }
234 
235 static void
236 kgdb_trgt_find_new_threads(struct target_ops *target_ops)
237 {
238 	struct target_ops *tb;
239 
240 	if (kvm != NULL)
241 		return;
242 
243 	tb = find_target_beneath(target_ops);
244 	if (tb->to_find_new_threads != NULL)
245 		tb->to_find_new_threads(target_ops);
246 }
247 
248 static char *
249 kgdb_trgt_pid_to_str(struct target_ops *target_ops __unused, ptid_t ptid)
250 {
251 	return (kgdb_thr_pid_to_str(ptid));
252 }
253 
254 static int
255 kgdb_trgt_thread_alive(struct target_ops *target_ops __unused, ptid_t ptid)
256 {
257 	return (kgdb_thr_lookup_tid(ptid_get_tid(ptid)) != NULL);
258 }
259 
260 static LONGEST
261 kgdb_trgt_xfer_partial(struct target_ops *ops, enum target_object object,
262 		       const char *annex, gdb_byte *readbuf,
263 		       const gdb_byte *writebuf,
264 		       ULONGEST offset, LONGEST len)
265 {
266 	if (kvm != NULL) {
267 		if (len == 0)
268 			return (0);
269 		if (writebuf != NULL)
270 			return (kvm_write(kvm, offset, writebuf, len));
271 		if (readbuf != NULL)
272 			return (kvm_read(kvm, offset, readbuf, len));
273 	}
274 	return (ops->beneath->to_xfer_partial(ops->beneath, object, annex,
275 					      readbuf, writebuf, offset, len));
276 }
277 
278 static void
279 kgdb_switch_to_thread(struct kthr *thr)
280 {
281 	char buf[16];
282 	CORE_ADDR thread_id;
283 	char *err;
284 
285 	thread_id = thr->tid;
286 	if (thread_id == 0)
287 		error ("invalid tid");
288 	snprintf(buf, sizeof(buf), "%lu", thread_id);
289 	if (!gdb_thread_select(current_uiout, buf, &err))
290 		error ("%s", err);
291 }
292 
293 static void
294 kgdb_set_proc_cmd (char *arg, int from_tty)
295 {
296 	CORE_ADDR addr;
297 	struct kthr *thr;
298 
299 	if (!arg)
300 		error_no_arg ("proc address for the new context");
301 
302 	if (kvm == NULL)
303 		error ("only supported for core file target");
304 
305 	addr = (CORE_ADDR) parse_and_eval_address (arg);
306 
307 	if (!INKERNEL (addr)) {
308 		thr = kgdb_thr_lookup_pid((int)addr);
309 		if (thr == NULL)
310 			error ("invalid pid");
311 	} else {
312 		thr = kgdb_thr_lookup_paddr(addr);
313 		if (thr == NULL)
314 			error("invalid proc address");
315 	}
316 	kgdb_switch_to_thread(thr);
317 }
318 
319 static void
320 kgdb_set_tid_cmd (char *arg, int from_tty)
321 {
322 	CORE_ADDR addr;
323 	struct kthr *thr;
324 
325 	if (!arg)
326 		error_no_arg ("Thread address for the new context");
327 
328 	addr = (CORE_ADDR) parse_and_eval_address (arg);
329 	thr = kgdb_thr_lookup_taddr(addr);
330 
331 	if (thr == NULL)
332 		error("invalid thread address");
333 
334 	kgdb_switch_to_thread(thr);
335 }
336 
337 int fbsdcoreops_suppress_target = 1;
338 
339 void
340 initialize_kgdb_target(void)
341 {
342 	kgdb_trgt_ops.to_magic = OPS_MAGIC;
343 	kgdb_trgt_ops.to_shortname = "kernel";
344 	kgdb_trgt_ops.to_longname = "kernel core dump file";
345 	kgdb_trgt_ops.to_doc =
346     "Use a vmcore file as a target.  Specify the filename of the vmcore file.";
347 	kgdb_trgt_ops.to_stratum = process_stratum;
348 	kgdb_trgt_ops.to_has_registers = default_child_has_registers;
349 	kgdb_trgt_ops.to_has_memory = default_child_has_memory;
350 	kgdb_trgt_ops.to_has_stack = default_child_has_stack;
351 
352 	kgdb_trgt_ops.to_open = kgdb_trgt_open;
353 	kgdb_trgt_ops.to_close = kgdb_trgt_close;
354 	kgdb_trgt_ops.to_attach = find_default_attach;
355 	kgdb_trgt_ops.to_detach = kgdb_trgt_detach;
356 	kgdb_trgt_ops.to_extra_thread_info = kgdb_trgt_extra_thread_info;
357 	kgdb_trgt_ops.to_fetch_registers = kgdb_trgt_fetch_registers;
358 	kgdb_trgt_ops.to_files_info = kgdb_trgt_files_info;
359 	kgdb_trgt_ops.to_find_new_threads = kgdb_trgt_find_new_threads;
360 	kgdb_trgt_ops.to_pid_to_str = kgdb_trgt_pid_to_str;
361 	/*
362 	kgdb_trgt_ops.to_store_registers = NULL;
363 	*/
364 	kgdb_trgt_ops.to_thread_alive = kgdb_trgt_thread_alive;
365 	kgdb_trgt_ops.to_xfer_partial = kgdb_trgt_xfer_partial;
366 	add_target(&kgdb_trgt_ops);
367 
368 	add_com ("proc", class_obscure, kgdb_set_proc_cmd,
369 	   "Set current process context");
370 	add_com ("tid", class_obscure, kgdb_set_tid_cmd,
371 	   "Set current thread context");
372 }
373