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 <command.h>
  41 #include <exec.h>
  42 #include <frame-unwind.h>
  43 #include <gdb.h>
  44 #include <gdbcore.h>
  45 #include <gdbthread.h>
  46 #include <inferior.h>
  47 #include <language.h>
  48 #include <regcache.h>
  49 #include <solib.h>
  50 #include <target.h>
  51 #include <ui-out.h>
  52
  53 #include "kgdb.h"
  54
  55 #ifdef CROSS_DEBUGGER
  56 /*
  57  * We suppress the call to add_target() of core_ops in corelow.c because if
  58  * there are multiple core_stratum targets, the find_core_target() function
  59  * won't know which one to return and returns none. We need it to return
  60  * our target. We only have to do that when we're building a cross-debugger
  61  * because fbsd-threads.c is part of a native debugger and it too defines
  62  * coreops_suppress_target with 1 as the initializer.
  63  */
  64 int coreops_suppress_target = 1;
  65 #endif
  66
  67 static CORE_ADDR stoppcbs;
  68
  69 static void     kgdb_core_cleanup(void *);
  70
  71 static char *vmcore;
  72 static struct target_ops kgdb_trgt_ops;
  73
  74 kvm_t *kvm;
  75 static char kvm_err[_POSIX2_LINE_MAX];
  76
  77 #define KERNOFF         (kgdb_kernbase ())
  78 #define PINKERNEL(x)    ((x) >= KERNOFF)
  79
  80 static int
  81 kgdb_resolve_symbol(const char *name, kvaddr_t *kva)
  82 {
  83         struct minimal_symbol *ms;
  84
  85         ms = lookup_minimal_symbol (name, NULL, NULL);
  86         if (ms == NULL)
  87                 return (1);
  88
  89         *kva = SYMBOL_VALUE_ADDRESS (ms);
  90         return (0);
  91 }
  92
  93 static CORE_ADDR
  94 kgdb_kernbase (void)
  95 {
  96         static CORE_ADDR kernbase;
  97         struct minimal_symbol *sym;
  98
  99         if (kernbase == 0) {
 100                 sym = lookup_minimal_symbol ("kernbase", NULL, NULL);
 101                 if (sym == NULL) {
 102                         kernbase = KERNBASE;
 103                 } else {
 104                         kernbase = SYMBOL_VALUE_ADDRESS (sym);
 105                 }
 106         }
 107         return kernbase;
 108 }
 109
 110 static void
 111 kgdb_trgt_open(char *filename, int from_tty)
 112 {
 113         struct cleanup *old_chain;
 114         struct thread_info *ti;
 115         struct kthr *kt;
 116         kvm_t *nkvm;
 117         char *temp;
 118         int ontop;
 119
 120         target_preopen (from_tty);
 121         if (!filename)
 122                 error ("No vmcore file specified.");
 123         if (!exec_bfd)
 124                 error ("Can't open a vmcore without a kernel");
 125
 126         filename = tilde_expand (filename);
 127         if (filename[0] != '/') {
 128                 temp = concat (current_directory, "/", filename, NULL);
 129                 xfree(filename);
 130                 filename = temp;
 131         }
 132
 133         old_chain = make_cleanup (xfree, filename);
 134
 135         nkvm = kvm_open2(bfd_get_filename(exec_bfd), filename,
 136             write_files ? O_RDWR : O_RDONLY, kvm_err, kgdb_resolve_symbol);
 137         if (nkvm == NULL)
 138                 error ("Failed to open vmcore: %s", kvm_err);
 139
 140         /* Don't free the filename now and close any previous vmcore. */
 141         discard_cleanups(old_chain);
 142         unpush_target(&kgdb_trgt_ops);
 143
 144         kvm = nkvm;
 145         vmcore = filename;
 146         old_chain = make_cleanup(kgdb_core_cleanup, NULL);
 147
 148         ontop = !push_target (&kgdb_trgt_ops);
 149         discard_cleanups (old_chain);
 150
 151         kgdb_dmesg();
 152
 153         init_thread_list();
 154         kt = kgdb_thr_init();
 155         while (kt != NULL) {
 156                 ti = add_thread(pid_to_ptid(kt->tid));
 157                 kt = kgdb_thr_next(kt);
 158         }
 159         if (curkthr != 0)
 160                 inferior_ptid = pid_to_ptid(curkthr->tid);
 161
 162         if (ontop) {
 163                 /* XXX: fetch registers? */
 164                 kld_init();
 165                 flush_cached_frames();
 166                 select_frame (get_current_frame());
 167                 print_stack_frame(get_selected_frame(),
 168                     frame_relative_level(get_selected_frame()), 1);
 169         } else
 170                 warning(
 171         "you won't be able to access this vmcore until you terminate\n\
 172 your %s; do ``info files''", target_longname);
 173 }
 174
 175 static void
 176 kgdb_trgt_close(int quitting)
 177 {
 178
 179         if (kvm != NULL) {
 180                 inferior_ptid = null_ptid;
 181                 CLEAR_SOLIB();
 182                 if (kvm_close(kvm) != 0)
 183                         warning("cannot close \"%s\": %s", vmcore,
 184                             kvm_geterr(kvm));
 185                 kvm = NULL;
 186                 xfree(vmcore);
 187                 vmcore = NULL;
 188                 if (kgdb_trgt_ops.to_sections) {
 189                         xfree(kgdb_trgt_ops.to_sections);
 190                         kgdb_trgt_ops.to_sections = NULL;
 191                         kgdb_trgt_ops.to_sections_end = NULL;
 192                 }
 193         }
 194 }
 195
 196 static void
 197 kgdb_core_cleanup(void *arg)
 198 {
 199
 200         kgdb_trgt_close(0);
 201 }
 202
 203 static void
 204 kgdb_trgt_detach(char *args, int from_tty)
 205 {
 206
 207         if (args)
 208                 error ("Too many arguments");
 209         unpush_target(&kgdb_trgt_ops);
 210         reinit_frame_cache();
 211         if (from_tty)
 212                 printf_filtered("No vmcore file now.\n");
 213 }
 214
 215 static char *
 216 kgdb_trgt_extra_thread_info(struct thread_info *ti)
 217 {
 218
 219         return (kgdb_thr_extra_thread_info(ptid_get_pid(ti->ptid)));
 220 }
 221
 222 static void
 223 kgdb_trgt_files_info(struct target_ops *target)
 224 {
 225
 226         printf_filtered ("\t`%s', ", vmcore);
 227         wrap_here ("        ");
 228         printf_filtered ("file type %s.\n", "FreeBSD kernel vmcore");
 229 }
 230
 231 static void
 232 kgdb_trgt_find_new_threads(void)
 233 {
 234         struct target_ops *tb;
 235
 236         if (kvm != NULL)
 237                 return;
 238
 239         tb = find_target_beneath(&kgdb_trgt_ops);
 240         if (tb->to_find_new_threads != NULL)
 241                 tb->to_find_new_threads();
 242 }
 243
 244 static char *
 245 kgdb_trgt_pid_to_str(ptid_t ptid)
 246 {
 247         static char buf[33];
 248
 249         snprintf(buf, sizeof(buf), "Thread %d", ptid_get_pid(ptid));
 250         return (buf);
 251 }
 252
 253 static int
 254 kgdb_trgt_thread_alive(ptid_t ptid)
 255 {
 256         return (kgdb_thr_lookup_tid(ptid_get_pid(ptid)) != NULL);
 257 }
 258
 259 static int
 260 kgdb_trgt_xfer_memory(CORE_ADDR memaddr, char *myaddr, int len, int write,
 261     struct mem_attrib *attrib, struct target_ops *target)
 262 {
 263         struct target_ops *tb;
 264
 265         if (kvm != NULL) {
 266                 if (len == 0)
 267                         return (0);
 268                 if (!write)
 269                         return (kvm_read2(kvm, memaddr, myaddr, len));
 270                 else
 271                         return (kvm_write(kvm, memaddr, myaddr, len));
 272         }
 273         tb = find_target_beneath(target);
 274         return (tb->to_xfer_memory(memaddr, myaddr, len, write, attrib, tb));
 275 }
 276
 277 static int
 278 kgdb_trgt_ignore_breakpoints(CORE_ADDR addr, char *contents)
 279 {
 280
 281         return 0;
 282 }
 283
 284 static void
 285 kgdb_switch_to_thread(int tid)
 286 {
 287         char buf[16];
 288         int thread_id;
 289
 290         thread_id = pid_to_thread_id(pid_to_ptid(tid));
 291         if (thread_id == 0)
 292                 error ("invalid tid");
 293         snprintf(buf, sizeof(buf), "%d", thread_id);
 294         gdb_thread_select(uiout, buf);
 295 }
 296
 297 static void
 298 kgdb_set_proc_cmd (char *arg, int from_tty)
 299 {
 300         CORE_ADDR addr;
 301         struct kthr *thr;
 302
 303         if (!arg)
 304                 error_no_arg ("proc address for the new context");
 305
 306         if (kvm == NULL)
 307                 error ("only supported for core file target");
 308
 309         addr = (CORE_ADDR) parse_and_eval_address (arg);
 310
 311         if (!PINKERNEL (addr)) {
 312                 thr = kgdb_thr_lookup_pid((int)addr);
 313                 if (thr == NULL)
 314                         error ("invalid pid");
 315         } else {
 316                 thr = kgdb_thr_lookup_paddr(addr);
 317                 if (thr == NULL)
 318                         error("invalid proc address");
 319         }
 320         kgdb_switch_to_thread(thr->tid);
 321 }
 322
 323 static void
 324 kgdb_set_tid_cmd (char *arg, int from_tty)
 325 {
 326         CORE_ADDR addr;
 327         struct kthr *thr;
 328
 329         if (!arg)
 330                 error_no_arg ("TID or thread address for the new context");
 331
 332         addr = (CORE_ADDR) parse_and_eval_address (arg);
 333
 334         if (kvm != NULL && PINKERNEL (addr)) {
 335                 thr = kgdb_thr_lookup_taddr(addr);
 336                 if (thr == NULL)
 337                         error("invalid thread address");
 338                 addr = thr->tid;
 339         }
 340         kgdb_switch_to_thread(addr);
 341 }
 342
 343 int fbsdcoreops_suppress_target = 1;
 344
 345 void
 346 initialize_kgdb_target(void)
 347 {
 348
 349         kgdb_trgt_ops.to_magic = OPS_MAGIC;
 350         kgdb_trgt_ops.to_shortname = "kernel";
 351         kgdb_trgt_ops.to_longname = "kernel core dump file";
 352         kgdb_trgt_ops.to_doc =
 353     "Use a vmcore file as a target.  Specify the filename of the vmcore file.";
 354         kgdb_trgt_ops.to_stratum = core_stratum;
 355         kgdb_trgt_ops.to_has_memory = 1;
 356         kgdb_trgt_ops.to_has_registers = 1;
 357         kgdb_trgt_ops.to_has_stack = 1;
 358
 359         kgdb_trgt_ops.to_open = kgdb_trgt_open;
 360         kgdb_trgt_ops.to_close = kgdb_trgt_close;
 361         kgdb_trgt_ops.to_attach = find_default_attach;
 362         kgdb_trgt_ops.to_detach = kgdb_trgt_detach;
 363         kgdb_trgt_ops.to_extra_thread_info = kgdb_trgt_extra_thread_info;
 364         kgdb_trgt_ops.to_fetch_registers = kgdb_trgt_fetch_registers;
 365         kgdb_trgt_ops.to_files_info = kgdb_trgt_files_info;
 366         kgdb_trgt_ops.to_find_new_threads = kgdb_trgt_find_new_threads;
 367         kgdb_trgt_ops.to_pid_to_str = kgdb_trgt_pid_to_str;
 368         kgdb_trgt_ops.to_store_registers = kgdb_trgt_store_registers;
 369         kgdb_trgt_ops.to_thread_alive = kgdb_trgt_thread_alive;
 370         kgdb_trgt_ops.to_xfer_memory = kgdb_trgt_xfer_memory;
 371         kgdb_trgt_ops.to_insert_breakpoint = kgdb_trgt_ignore_breakpoints;
 372         kgdb_trgt_ops.to_remove_breakpoint = kgdb_trgt_ignore_breakpoints;
 373
 374         add_target(&kgdb_trgt_ops);
 375
 376         add_com ("proc", class_obscure, kgdb_set_proc_cmd,
 377            "Set current process context");
 378         add_com ("tid", class_obscure, kgdb_set_tid_cmd,
 379            "Set current thread context");
 380 }
 381
 382 CORE_ADDR
 383 kgdb_trgt_stop_pcb(u_int cpuid, u_int pcbsz)
 384 {
 385         static int once = 0;
 386
 387         if (stoppcbs == 0 && !once) {
 388                 once = 1;
 389                 stoppcbs = kgdb_lookup("stoppcbs");
 390         }
 391         if (stoppcbs == 0)
 392                 return 0;
 393
 394         return (stoppcbs + pcbsz * cpuid);
 395 }