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