xref: /dragonfly/gnu/usr.bin/gdb/kgdb/trgt.c (revision c33252afc5aa9790d4820b568316e03d695f6a65)
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
kgdb_kernbase(void)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
kgdb_trgt_open(char * filename,int from_tty)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
kgdb_trgt_close(int quitting)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
kgdb_core_cleanup(void * arg)201 kgdb_core_cleanup(void *arg)
202 {
203 
204           kgdb_trgt_close(0);
205 }
206 
207 static void
kgdb_trgt_detach(struct target_ops * target,char * args,int from_tty)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 *
kgdb_trgt_extra_thread_info(struct thread_info * ti)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
kgdb_trgt_files_info(struct target_ops * target)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
kgdb_trgt_find_new_threads(struct target_ops * target_ops)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 *
kgdb_trgt_pid_to_str(struct target_ops * target_ops __unused,ptid_t ptid)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
kgdb_trgt_thread_alive(struct target_ops * target_ops __unused,ptid_t ptid)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
kgdb_trgt_xfer_partial(struct target_ops * ops,enum target_object object,const char * annex,gdb_byte * readbuf,const gdb_byte * writebuf,ULONGEST offset,LONGEST len)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
kgdb_switch_to_thread(struct kthr * thr)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
kgdb_set_proc_cmd(char * arg,int from_tty)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
kgdb_set_tid_cmd(char * arg,int from_tty)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
initialize_kgdb_target(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