gnu/usr.bin/gdb/kgdb/trgt.c

   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 static CORE_ADDR stoppcbs;
  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 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\
 148 your %s; do ``info files''", target_longname);
 149 }
 150
 151 static void
 152 kgdb_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
 172 static void
 173 kgdb_core_cleanup(void *arg)
 174 {
 175
 176         kgdb_trgt_close(0);
 177 }
 178
 179 static void
 180 kgdb_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
 191 static char *
 192 kgdb_trgt_extra_thread_info(struct thread_info *ti)
 193 {
 194
 195         return (kgdb_thr_extra_thread_info(ptid_get_pid(ti->ptid)));
 196 }
 197
 198 static void
 199 kgdb_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
 207 static void
 208 kgdb_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
 220 static char *
 221 kgdb_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
 229 static int
 230 kgdb_trgt_thread_alive(ptid_t ptid)
 231 {
 232         return (kgdb_thr_lookup_tid(ptid_get_pid(ptid)) != NULL);
 233 }
 234
 235 static int
 236 kgdb_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
 253 static int
 254 kgdb_trgt_ignore_breakpoints(CORE_ADDR addr, char *contents)
 255 {
 256
 257         return 0;
 258 }
 259
 260 static void
 261 kgdb_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
 273 static void
 274 kgdb_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 (!INKERNEL (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
 299 static void
 300 kgdb_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 && INKERNEL (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
 319 int fbsdcoreops_suppress_target = 1;
 320
 321 void
 322 initialize_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
 358 CORE_ADDR
 359 kgdb_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 }