trgt.c revision 286305 
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: stable/10/gnu/usr.bin/gdb/kgdb/trgt.c 286305 2015-08-05 07:21:44Z kib $");
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
56static CORE_ADDR stoppcbs;
57
58static void	kgdb_core_cleanup(void *);
59
60static char *vmcore;
61static struct target_ops kgdb_trgt_ops;
62
63kvm_t *kvm;
64static char kvm_err[_POSIX2_LINE_MAX];
65
66#define	KERNOFF		(kgdb_kernbase ())
67#define	PINKERNEL(x)	((x) >= KERNOFF)
68
69static CORE_ADDR
70kgdb_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
86static void
87kgdb_trgt_open(char *filename, int from_tty)
88{
89	struct cleanup *old_chain;
90	struct thread_info *ti;
91	struct kthr *kt;
92	kvm_t *nkvm;
93	char *temp;
94	int ontop;
95
96	target_preopen (from_tty);
97	if (!filename)
98		error ("No vmcore file specified.");
99	if (!exec_bfd)
100		error ("Can't open a vmcore without a kernel");
101
102	filename = tilde_expand (filename);
103	if (filename[0] != '/') {
104		temp = concat (current_directory, "/", filename, NULL);
105		xfree(filename);
106		filename = temp;
107	}
108
109	old_chain = make_cleanup (xfree, filename);
110
111	nkvm = kvm_openfiles(bfd_get_filename(exec_bfd), filename, NULL,
112	    write_files ? O_RDWR : O_RDONLY, kvm_err);
113	if (nkvm == NULL)
114		error ("Failed to open vmcore: %s", kvm_err);
115
116	/* Don't free the filename now and close any previous vmcore. */
117	discard_cleanups(old_chain);
118	unpush_target(&kgdb_trgt_ops);
119
120	kvm = nkvm;
121	vmcore = filename;
122	old_chain = make_cleanup(kgdb_core_cleanup, NULL);
123
124	ontop = !push_target (&kgdb_trgt_ops);
125	discard_cleanups (old_chain);
126
127	kgdb_dmesg();
128
129	init_thread_list();
130	kt = kgdb_thr_init();
131	while (kt != NULL) {
132		ti = add_thread(pid_to_ptid(kt->tid));
133		kt = kgdb_thr_next(kt);
134	}
135	if (curkthr != 0)
136		inferior_ptid = pid_to_ptid(curkthr->tid);
137
138	if (ontop) {
139		/* XXX: fetch registers? */
140		kld_init();
141		flush_cached_frames();
142		select_frame (get_current_frame());
143		print_stack_frame(get_selected_frame(),
144		    frame_relative_level(get_selected_frame()), 1);
145	} else
146		warning(
147	"you won't be able to access this vmcore until you terminate\n\
148your %s; do ``info files''", target_longname);
149}
150
151static void
152kgdb_trgt_close(int quitting)
153{
154
155	if (kvm != NULL) {
156		inferior_ptid = null_ptid;
157		CLEAR_SOLIB();
158		if (kvm_close(kvm) != 0)
159			warning("cannot close \"%s\": %s", vmcore,
160			    kvm_geterr(kvm));
161		kvm = NULL;
162		xfree(vmcore);
163		vmcore = NULL;
164		if (kgdb_trgt_ops.to_sections) {
165			xfree(kgdb_trgt_ops.to_sections);
166			kgdb_trgt_ops.to_sections = NULL;
167			kgdb_trgt_ops.to_sections_end = NULL;
168		}
169	}
170}
171
172static void
173kgdb_core_cleanup(void *arg)
174{
175
176	kgdb_trgt_close(0);
177}
178
179static void
180kgdb_trgt_detach(char *args, int from_tty)
181{
182
183	if (args)
184		error ("Too many arguments");
185	unpush_target(&kgdb_trgt_ops);
186	reinit_frame_cache();
187	if (from_tty)
188		printf_filtered("No vmcore file now.\n");
189}
190
191static char *
192kgdb_trgt_extra_thread_info(struct thread_info *ti)
193{
194
195	return (kgdb_thr_extra_thread_info(ptid_get_pid(ti->ptid)));
196}
197
198static void
199kgdb_trgt_files_info(struct target_ops *target)
200{
201
202	printf_filtered ("\t`%s', ", vmcore);
203	wrap_here ("        ");
204	printf_filtered ("file type %s.\n", "FreeBSD kernel vmcore");
205}
206
207static void
208kgdb_trgt_find_new_threads(void)
209{
210	struct target_ops *tb;
211
212	if (kvm != NULL)
213		return;
214
215	tb = find_target_beneath(&kgdb_trgt_ops);
216	if (tb->to_find_new_threads != NULL)
217		tb->to_find_new_threads();
218}
219
220static char *
221kgdb_trgt_pid_to_str(ptid_t ptid)
222{
223	static char buf[33];
224
225	snprintf(buf, sizeof(buf), "Thread %d", ptid_get_pid(ptid));
226	return (buf);
227}
228
229static int
230kgdb_trgt_thread_alive(ptid_t ptid)
231{
232	return (kgdb_thr_lookup_tid(ptid_get_pid(ptid)) != NULL);
233}
234
235static int
236kgdb_trgt_xfer_memory(CORE_ADDR memaddr, char *myaddr, int len, int write,
237    struct mem_attrib *attrib, struct target_ops *target)
238{
239	struct target_ops *tb;
240
241	if (kvm != NULL) {
242		if (len == 0)
243			return (0);
244		if (!write)
245			return (kvm_read(kvm, memaddr, myaddr, len));
246		else
247			return (kvm_write(kvm, memaddr, myaddr, len));
248	}
249	tb = find_target_beneath(target);
250	return (tb->to_xfer_memory(memaddr, myaddr, len, write, attrib, tb));
251}
252
253static int
254kgdb_trgt_ignore_breakpoints(CORE_ADDR addr, char *contents)
255{
256
257	return 0;
258}
259
260static void
261kgdb_switch_to_thread(int tid)
262{
263	char buf[16];
264	int thread_id;
265
266	thread_id = pid_to_thread_id(pid_to_ptid(tid));
267	if (thread_id == 0)
268		error ("invalid tid");
269	snprintf(buf, sizeof(buf), "%d", thread_id);
270	gdb_thread_select(uiout, buf);
271}
272
273static void
274kgdb_set_proc_cmd (char *arg, int from_tty)
275{
276	CORE_ADDR addr;
277	struct kthr *thr;
278
279	if (!arg)
280		error_no_arg ("proc address for the new context");
281
282	if (kvm == NULL)
283		error ("only supported for core file target");
284
285	addr = (CORE_ADDR) parse_and_eval_address (arg);
286
287	if (!PINKERNEL (addr)) {
288		thr = kgdb_thr_lookup_pid((int)addr);
289		if (thr == NULL)
290			error ("invalid pid");
291	} else {
292		thr = kgdb_thr_lookup_paddr(addr);
293		if (thr == NULL)
294			error("invalid proc address");
295	}
296	kgdb_switch_to_thread(thr->tid);
297}
298
299static void
300kgdb_set_tid_cmd (char *arg, int from_tty)
301{
302	CORE_ADDR addr;
303	struct kthr *thr;
304
305	if (!arg)
306		error_no_arg ("TID or thread address for the new context");
307
308	addr = (CORE_ADDR) parse_and_eval_address (arg);
309
310	if (kvm != NULL && PINKERNEL (addr)) {
311		thr = kgdb_thr_lookup_taddr(addr);
312		if (thr == NULL)
313			error("invalid thread address");
314		addr = thr->tid;
315	}
316	kgdb_switch_to_thread(addr);
317}
318
319int fbsdcoreops_suppress_target = 1;
320
321void
322initialize_kgdb_target(void)
323{
324
325	kgdb_trgt_ops.to_magic = OPS_MAGIC;
326	kgdb_trgt_ops.to_shortname = "kernel";
327	kgdb_trgt_ops.to_longname = "kernel core dump file";
328	kgdb_trgt_ops.to_doc =
329    "Use a vmcore file as a target.  Specify the filename of the vmcore file.";
330	kgdb_trgt_ops.to_stratum = core_stratum;
331	kgdb_trgt_ops.to_has_memory = 1;
332	kgdb_trgt_ops.to_has_registers = 1;
333	kgdb_trgt_ops.to_has_stack = 1;
334
335	kgdb_trgt_ops.to_open = kgdb_trgt_open;
336	kgdb_trgt_ops.to_close = kgdb_trgt_close;
337	kgdb_trgt_ops.to_attach = find_default_attach;
338	kgdb_trgt_ops.to_detach = kgdb_trgt_detach;
339	kgdb_trgt_ops.to_extra_thread_info = kgdb_trgt_extra_thread_info;
340	kgdb_trgt_ops.to_fetch_registers = kgdb_trgt_fetch_registers;
341	kgdb_trgt_ops.to_files_info = kgdb_trgt_files_info;
342	kgdb_trgt_ops.to_find_new_threads = kgdb_trgt_find_new_threads;
343	kgdb_trgt_ops.to_pid_to_str = kgdb_trgt_pid_to_str;
344	kgdb_trgt_ops.to_store_registers = kgdb_trgt_store_registers;
345	kgdb_trgt_ops.to_thread_alive = kgdb_trgt_thread_alive;
346	kgdb_trgt_ops.to_xfer_memory = kgdb_trgt_xfer_memory;
347	kgdb_trgt_ops.to_insert_breakpoint = kgdb_trgt_ignore_breakpoints;
348	kgdb_trgt_ops.to_remove_breakpoint = kgdb_trgt_ignore_breakpoints;
349
350	add_target(&kgdb_trgt_ops);
351
352	add_com ("proc", class_obscure, kgdb_set_proc_cmd,
353	   "Set current process context");
354	add_com ("tid", class_obscure, kgdb_set_tid_cmd,
355	   "Set current thread context");
356}
357
358CORE_ADDR
359kgdb_trgt_stop_pcb(u_int cpuid, u_int pcbsz)
360{
361	static int once = 0;
362
363	if (stoppcbs == 0 && !once) {
364		once = 1;
365		stoppcbs = kgdb_lookup("stoppcbs");
366	}
367	if (stoppcbs == 0)
368		return 0;
369
370	return (stoppcbs + pcbsz * cpuid);
371}
372