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 #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
  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
  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
 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
 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
 198 kgdb_core_cleanup(void *arg)
 199 {
 200
 201         kgdb_trgt_close(0);
 202 }
 203
 204 static void
 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 *
 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
 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
 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 *
 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
 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
 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
 279 kgdb_trgt_ignore_breakpoints(CORE_ADDR addr, char *contents)
 280 {
 281
 282         return 0;
 283 }
 284
 285 static void
 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
 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
 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
 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
 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 }