kdb: Allow kernel loadable modules to add kdb shell functions
[linux-3.10.git] / kernel / debug / kdb / kdb_main.c
1 /*
2  * Kernel Debugger Architecture Independent Main Code
3  *
4  * This file is subject to the terms and conditions of the GNU General Public
5  * License.  See the file "COPYING" in the main directory of this archive
6  * for more details.
7  *
8  * Copyright (C) 1999-2004 Silicon Graphics, Inc.  All Rights Reserved.
9  * Copyright (C) 2000 Stephane Eranian <eranian@hpl.hp.com>
10  * Xscale (R) modifications copyright (C) 2003 Intel Corporation.
11  * Copyright (c) 2009 Wind River Systems, Inc.  All Rights Reserved.
12  */
13
14 #include <linux/ctype.h>
15 #include <linux/string.h>
16 #include <linux/kernel.h>
17 #include <linux/reboot.h>
18 #include <linux/sched.h>
19 #include <linux/sysrq.h>
20 #include <linux/smp.h>
21 #include <linux/utsname.h>
22 #include <linux/vmalloc.h>
23 #include <linux/module.h>
24 #include <linux/mm.h>
25 #include <linux/init.h>
26 #include <linux/kallsyms.h>
27 #include <linux/kgdb.h>
28 #include <linux/kdb.h>
29 #include <linux/notifier.h>
30 #include <linux/interrupt.h>
31 #include <linux/delay.h>
32 #include <linux/nmi.h>
33 #include <linux/time.h>
34 #include <linux/ptrace.h>
35 #include <linux/sysctl.h>
36 #include <linux/cpu.h>
37 #include <linux/kdebug.h>
38 #include <linux/proc_fs.h>
39 #include <linux/uaccess.h>
40 #include <linux/slab.h>
41 #include "kdb_private.h"
42
43 #define GREP_LEN 256
44 char kdb_grep_string[GREP_LEN];
45 int kdb_grepping_flag;
46 EXPORT_SYMBOL(kdb_grepping_flag);
47 int kdb_grep_leading;
48 int kdb_grep_trailing;
49
50 /*
51  * Kernel debugger state flags
52  */
53 int kdb_flags;
54 atomic_t kdb_event;
55
56 /*
57  * kdb_lock protects updates to kdb_initial_cpu.  Used to
58  * single thread processors through the kernel debugger.
59  */
60 int kdb_initial_cpu = -1;       /* cpu number that owns kdb */
61 int kdb_nextline = 1;
62 int kdb_state;                  /* General KDB state */
63
64 struct task_struct *kdb_current_task;
65 EXPORT_SYMBOL(kdb_current_task);
66 struct pt_regs *kdb_current_regs;
67
68 const char *kdb_diemsg;
69 static int kdb_go_count;
70 #ifdef CONFIG_KDB_CONTINUE_CATASTROPHIC
71 static unsigned int kdb_continue_catastrophic =
72         CONFIG_KDB_CONTINUE_CATASTROPHIC;
73 #else
74 static unsigned int kdb_continue_catastrophic;
75 #endif
76
77 /* kdb_commands describes the available commands. */
78 static kdbtab_t *kdb_commands;
79 #define KDB_BASE_CMD_MAX 50
80 static int kdb_max_commands = KDB_BASE_CMD_MAX;
81 static kdbtab_t kdb_base_commands[50];
82 #define for_each_kdbcmd(cmd, num)                                       \
83         for ((cmd) = kdb_base_commands, (num) = 0;                      \
84              num < kdb_max_commands;                                    \
85              num == KDB_BASE_CMD_MAX ? cmd = kdb_commands : cmd++, num++)
86
87 typedef struct _kdbmsg {
88         int     km_diag;        /* kdb diagnostic */
89         char    *km_msg;        /* Corresponding message text */
90 } kdbmsg_t;
91
92 #define KDBMSG(msgnum, text) \
93         { KDB_##msgnum, text }
94
95 static kdbmsg_t kdbmsgs[] = {
96         KDBMSG(NOTFOUND, "Command Not Found"),
97         KDBMSG(ARGCOUNT, "Improper argument count, see usage."),
98         KDBMSG(BADWIDTH, "Illegal value for BYTESPERWORD use 1, 2, 4 or 8, "
99                "8 is only allowed on 64 bit systems"),
100         KDBMSG(BADRADIX, "Illegal value for RADIX use 8, 10 or 16"),
101         KDBMSG(NOTENV, "Cannot find environment variable"),
102         KDBMSG(NOENVVALUE, "Environment variable should have value"),
103         KDBMSG(NOTIMP, "Command not implemented"),
104         KDBMSG(ENVFULL, "Environment full"),
105         KDBMSG(ENVBUFFULL, "Environment buffer full"),
106         KDBMSG(TOOMANYBPT, "Too many breakpoints defined"),
107 #ifdef CONFIG_CPU_XSCALE
108         KDBMSG(TOOMANYDBREGS, "More breakpoints than ibcr registers defined"),
109 #else
110         KDBMSG(TOOMANYDBREGS, "More breakpoints than db registers defined"),
111 #endif
112         KDBMSG(DUPBPT, "Duplicate breakpoint address"),
113         KDBMSG(BPTNOTFOUND, "Breakpoint not found"),
114         KDBMSG(BADMODE, "Invalid IDMODE"),
115         KDBMSG(BADINT, "Illegal numeric value"),
116         KDBMSG(INVADDRFMT, "Invalid symbolic address format"),
117         KDBMSG(BADREG, "Invalid register name"),
118         KDBMSG(BADCPUNUM, "Invalid cpu number"),
119         KDBMSG(BADLENGTH, "Invalid length field"),
120         KDBMSG(NOBP, "No Breakpoint exists"),
121         KDBMSG(BADADDR, "Invalid address"),
122 };
123 #undef KDBMSG
124
125 static const int __nkdb_err = sizeof(kdbmsgs) / sizeof(kdbmsg_t);
126
127
128 /*
129  * Initial environment.   This is all kept static and local to
130  * this file.   We don't want to rely on the memory allocation
131  * mechanisms in the kernel, so we use a very limited allocate-only
132  * heap for new and altered environment variables.  The entire
133  * environment is limited to a fixed number of entries (add more
134  * to __env[] if required) and a fixed amount of heap (add more to
135  * KDB_ENVBUFSIZE if required).
136  */
137
138 static char *__env[] = {
139 #if defined(CONFIG_SMP)
140  "PROMPT=[%d]kdb> ",
141  "MOREPROMPT=[%d]more> ",
142 #else
143  "PROMPT=kdb> ",
144  "MOREPROMPT=more> ",
145 #endif
146  "RADIX=16",
147  "MDCOUNT=8",                   /* lines of md output */
148  "BTARGS=9",                    /* 9 possible args in bt */
149  KDB_PLATFORM_ENV,
150  "DTABCOUNT=30",
151  "NOSECT=1",
152  (char *)0,
153  (char *)0,
154  (char *)0,
155  (char *)0,
156  (char *)0,
157  (char *)0,
158  (char *)0,
159  (char *)0,
160  (char *)0,
161  (char *)0,
162  (char *)0,
163  (char *)0,
164  (char *)0,
165  (char *)0,
166  (char *)0,
167  (char *)0,
168  (char *)0,
169  (char *)0,
170  (char *)0,
171  (char *)0,
172  (char *)0,
173  (char *)0,
174  (char *)0,
175 };
176
177 static const int __nenv = (sizeof(__env) / sizeof(char *));
178
179 struct task_struct *kdb_curr_task(int cpu)
180 {
181         struct task_struct *p = curr_task(cpu);
182 #ifdef  _TIF_MCA_INIT
183         if ((task_thread_info(p)->flags & _TIF_MCA_INIT) && KDB_TSK(cpu))
184                 p = krp->p;
185 #endif
186         return p;
187 }
188
189 /*
190  * kdbgetenv - This function will return the character string value of
191  *      an environment variable.
192  * Parameters:
193  *      match   A character string representing an environment variable.
194  * Returns:
195  *      NULL    No environment variable matches 'match'
196  *      char*   Pointer to string value of environment variable.
197  */
198 char *kdbgetenv(const char *match)
199 {
200         char **ep = __env;
201         int matchlen = strlen(match);
202         int i;
203
204         for (i = 0; i < __nenv; i++) {
205                 char *e = *ep++;
206
207                 if (!e)
208                         continue;
209
210                 if ((strncmp(match, e, matchlen) == 0)
211                  && ((e[matchlen] == '\0')
212                    || (e[matchlen] == '='))) {
213                         char *cp = strchr(e, '=');
214                         return cp ? ++cp : "";
215                 }
216         }
217         return NULL;
218 }
219
220 /*
221  * kdballocenv - This function is used to allocate bytes for
222  *      environment entries.
223  * Parameters:
224  *      match   A character string representing a numeric value
225  * Outputs:
226  *      *value  the unsigned long representation of the env variable 'match'
227  * Returns:
228  *      Zero on success, a kdb diagnostic on failure.
229  * Remarks:
230  *      We use a static environment buffer (envbuffer) to hold the values
231  *      of dynamically generated environment variables (see kdb_set).  Buffer
232  *      space once allocated is never free'd, so over time, the amount of space
233  *      (currently 512 bytes) will be exhausted if env variables are changed
234  *      frequently.
235  */
236 static char *kdballocenv(size_t bytes)
237 {
238 #define KDB_ENVBUFSIZE  512
239         static char envbuffer[KDB_ENVBUFSIZE];
240         static int envbufsize;
241         char *ep = NULL;
242
243         if ((KDB_ENVBUFSIZE - envbufsize) >= bytes) {
244                 ep = &envbuffer[envbufsize];
245                 envbufsize += bytes;
246         }
247         return ep;
248 }
249
250 /*
251  * kdbgetulenv - This function will return the value of an unsigned
252  *      long-valued environment variable.
253  * Parameters:
254  *      match   A character string representing a numeric value
255  * Outputs:
256  *      *value  the unsigned long represntation of the env variable 'match'
257  * Returns:
258  *      Zero on success, a kdb diagnostic on failure.
259  */
260 static int kdbgetulenv(const char *match, unsigned long *value)
261 {
262         char *ep;
263
264         ep = kdbgetenv(match);
265         if (!ep)
266                 return KDB_NOTENV;
267         if (strlen(ep) == 0)
268                 return KDB_NOENVVALUE;
269
270         *value = simple_strtoul(ep, NULL, 0);
271
272         return 0;
273 }
274
275 /*
276  * kdbgetintenv - This function will return the value of an
277  *      integer-valued environment variable.
278  * Parameters:
279  *      match   A character string representing an integer-valued env variable
280  * Outputs:
281  *      *value  the integer representation of the environment variable 'match'
282  * Returns:
283  *      Zero on success, a kdb diagnostic on failure.
284  */
285 int kdbgetintenv(const char *match, int *value)
286 {
287         unsigned long val;
288         int diag;
289
290         diag = kdbgetulenv(match, &val);
291         if (!diag)
292                 *value = (int) val;
293         return diag;
294 }
295
296 /*
297  * kdbgetularg - This function will convert a numeric string into an
298  *      unsigned long value.
299  * Parameters:
300  *      arg     A character string representing a numeric value
301  * Outputs:
302  *      *value  the unsigned long represntation of arg.
303  * Returns:
304  *      Zero on success, a kdb diagnostic on failure.
305  */
306 int kdbgetularg(const char *arg, unsigned long *value)
307 {
308         char *endp;
309         unsigned long val;
310
311         val = simple_strtoul(arg, &endp, 0);
312
313         if (endp == arg) {
314                 /*
315                  * Also try base 16, for us folks too lazy to type the
316                  * leading 0x...
317                  */
318                 val = simple_strtoul(arg, &endp, 16);
319                 if (endp == arg)
320                         return KDB_BADINT;
321         }
322
323         *value = val;
324
325         return 0;
326 }
327
328 int kdbgetu64arg(const char *arg, u64 *value)
329 {
330         char *endp;
331         u64 val;
332
333         val = simple_strtoull(arg, &endp, 0);
334
335         if (endp == arg) {
336
337                 val = simple_strtoull(arg, &endp, 16);
338                 if (endp == arg)
339                         return KDB_BADINT;
340         }
341
342         *value = val;
343
344         return 0;
345 }
346
347 /*
348  * kdb_set - This function implements the 'set' command.  Alter an
349  *      existing environment variable or create a new one.
350  */
351 int kdb_set(int argc, const char **argv)
352 {
353         int i;
354         char *ep;
355         size_t varlen, vallen;
356
357         /*
358          * we can be invoked two ways:
359          *   set var=value    argv[1]="var", argv[2]="value"
360          *   set var = value  argv[1]="var", argv[2]="=", argv[3]="value"
361          * - if the latter, shift 'em down.
362          */
363         if (argc == 3) {
364                 argv[2] = argv[3];
365                 argc--;
366         }
367
368         if (argc != 2)
369                 return KDB_ARGCOUNT;
370
371         /*
372          * Check for internal variables
373          */
374         if (strcmp(argv[1], "KDBDEBUG") == 0) {
375                 unsigned int debugflags;
376                 char *cp;
377
378                 debugflags = simple_strtoul(argv[2], &cp, 0);
379                 if (cp == argv[2] || debugflags & ~KDB_DEBUG_FLAG_MASK) {
380                         kdb_printf("kdb: illegal debug flags '%s'\n",
381                                     argv[2]);
382                         return 0;
383                 }
384                 kdb_flags = (kdb_flags &
385                              ~(KDB_DEBUG_FLAG_MASK << KDB_DEBUG_FLAG_SHIFT))
386                         | (debugflags << KDB_DEBUG_FLAG_SHIFT);
387
388                 return 0;
389         }
390
391         /*
392          * Tokenizer squashed the '=' sign.  argv[1] is variable
393          * name, argv[2] = value.
394          */
395         varlen = strlen(argv[1]);
396         vallen = strlen(argv[2]);
397         ep = kdballocenv(varlen + vallen + 2);
398         if (ep == (char *)0)
399                 return KDB_ENVBUFFULL;
400
401         sprintf(ep, "%s=%s", argv[1], argv[2]);
402
403         ep[varlen+vallen+1] = '\0';
404
405         for (i = 0; i < __nenv; i++) {
406                 if (__env[i]
407                  && ((strncmp(__env[i], argv[1], varlen) == 0)
408                    && ((__env[i][varlen] == '\0')
409                     || (__env[i][varlen] == '=')))) {
410                         __env[i] = ep;
411                         return 0;
412                 }
413         }
414
415         /*
416          * Wasn't existing variable.  Fit into slot.
417          */
418         for (i = 0; i < __nenv-1; i++) {
419                 if (__env[i] == (char *)0) {
420                         __env[i] = ep;
421                         return 0;
422                 }
423         }
424
425         return KDB_ENVFULL;
426 }
427
428 static int kdb_check_regs(void)
429 {
430         if (!kdb_current_regs) {
431                 kdb_printf("No current kdb registers."
432                            "  You may need to select another task\n");
433                 return KDB_BADREG;
434         }
435         return 0;
436 }
437
438 /*
439  * kdbgetaddrarg - This function is responsible for parsing an
440  *      address-expression and returning the value of the expression,
441  *      symbol name, and offset to the caller.
442  *
443  *      The argument may consist of a numeric value (decimal or
444  *      hexidecimal), a symbol name, a register name (preceeded by the
445  *      percent sign), an environment variable with a numeric value
446  *      (preceeded by a dollar sign) or a simple arithmetic expression
447  *      consisting of a symbol name, +/-, and a numeric constant value
448  *      (offset).
449  * Parameters:
450  *      argc    - count of arguments in argv
451  *      argv    - argument vector
452  *      *nextarg - index to next unparsed argument in argv[]
453  *      regs    - Register state at time of KDB entry
454  * Outputs:
455  *      *value  - receives the value of the address-expression
456  *      *offset - receives the offset specified, if any
457  *      *name   - receives the symbol name, if any
458  *      *nextarg - index to next unparsed argument in argv[]
459  * Returns:
460  *      zero is returned on success, a kdb diagnostic code is
461  *      returned on error.
462  */
463 int kdbgetaddrarg(int argc, const char **argv, int *nextarg,
464                   unsigned long *value,  long *offset,
465                   char **name)
466 {
467         unsigned long addr;
468         unsigned long off = 0;
469         int positive;
470         int diag;
471         int found = 0;
472         char *symname;
473         char symbol = '\0';
474         char *cp;
475         kdb_symtab_t symtab;
476
477         /*
478          * Process arguments which follow the following syntax:
479          *
480          *  symbol | numeric-address [+/- numeric-offset]
481          *  %register
482          *  $environment-variable
483          */
484
485         if (*nextarg > argc)
486                 return KDB_ARGCOUNT;
487
488         symname = (char *)argv[*nextarg];
489
490         /*
491          * If there is no whitespace between the symbol
492          * or address and the '+' or '-' symbols, we
493          * remember the character and replace it with a
494          * null so the symbol/value can be properly parsed
495          */
496         cp = strpbrk(symname, "+-");
497         if (cp != NULL) {
498                 symbol = *cp;
499                 *cp++ = '\0';
500         }
501
502         if (symname[0] == '$') {
503                 diag = kdbgetulenv(&symname[1], &addr);
504                 if (diag)
505                         return diag;
506         } else if (symname[0] == '%') {
507                 diag = kdb_check_regs();
508                 if (diag)
509                         return diag;
510                 /* Implement register values with % at a later time as it is
511                  * arch optional.
512                  */
513                 return KDB_NOTIMP;
514         } else {
515                 found = kdbgetsymval(symname, &symtab);
516                 if (found) {
517                         addr = symtab.sym_start;
518                 } else {
519                         diag = kdbgetularg(argv[*nextarg], &addr);
520                         if (diag)
521                                 return diag;
522                 }
523         }
524
525         if (!found)
526                 found = kdbnearsym(addr, &symtab);
527
528         (*nextarg)++;
529
530         if (name)
531                 *name = symname;
532         if (value)
533                 *value = addr;
534         if (offset && name && *name)
535                 *offset = addr - symtab.sym_start;
536
537         if ((*nextarg > argc)
538          && (symbol == '\0'))
539                 return 0;
540
541         /*
542          * check for +/- and offset
543          */
544
545         if (symbol == '\0') {
546                 if ((argv[*nextarg][0] != '+')
547                  && (argv[*nextarg][0] != '-')) {
548                         /*
549                          * Not our argument.  Return.
550                          */
551                         return 0;
552                 } else {
553                         positive = (argv[*nextarg][0] == '+');
554                         (*nextarg)++;
555                 }
556         } else
557                 positive = (symbol == '+');
558
559         /*
560          * Now there must be an offset!
561          */
562         if ((*nextarg > argc)
563          && (symbol == '\0')) {
564                 return KDB_INVADDRFMT;
565         }
566
567         if (!symbol) {
568                 cp = (char *)argv[*nextarg];
569                 (*nextarg)++;
570         }
571
572         diag = kdbgetularg(cp, &off);
573         if (diag)
574                 return diag;
575
576         if (!positive)
577                 off = -off;
578
579         if (offset)
580                 *offset += off;
581
582         if (value)
583                 *value += off;
584
585         return 0;
586 }
587
588 static void kdb_cmderror(int diag)
589 {
590         int i;
591
592         if (diag >= 0) {
593                 kdb_printf("no error detected (diagnostic is %d)\n", diag);
594                 return;
595         }
596
597         for (i = 0; i < __nkdb_err; i++) {
598                 if (kdbmsgs[i].km_diag == diag) {
599                         kdb_printf("diag: %d: %s\n", diag, kdbmsgs[i].km_msg);
600                         return;
601                 }
602         }
603
604         kdb_printf("Unknown diag %d\n", -diag);
605 }
606
607 /*
608  * kdb_defcmd, kdb_defcmd2 - This function implements the 'defcmd'
609  *      command which defines one command as a set of other commands,
610  *      terminated by endefcmd.  kdb_defcmd processes the initial
611  *      'defcmd' command, kdb_defcmd2 is invoked from kdb_parse for
612  *      the following commands until 'endefcmd'.
613  * Inputs:
614  *      argc    argument count
615  *      argv    argument vector
616  * Returns:
617  *      zero for success, a kdb diagnostic if error
618  */
619 struct defcmd_set {
620         int count;
621         int usable;
622         char *name;
623         char *usage;
624         char *help;
625         char **command;
626 };
627 static struct defcmd_set *defcmd_set;
628 static int defcmd_set_count;
629 static int defcmd_in_progress;
630
631 /* Forward references */
632 static int kdb_exec_defcmd(int argc, const char **argv);
633
634 static int kdb_defcmd2(const char *cmdstr, const char *argv0)
635 {
636         struct defcmd_set *s = defcmd_set + defcmd_set_count - 1;
637         char **save_command = s->command;
638         if (strcmp(argv0, "endefcmd") == 0) {
639                 defcmd_in_progress = 0;
640                 if (!s->count)
641                         s->usable = 0;
642                 if (s->usable)
643                         kdb_register(s->name, kdb_exec_defcmd,
644                                      s->usage, s->help, 0);
645                 return 0;
646         }
647         if (!s->usable)
648                 return KDB_NOTIMP;
649         s->command = kmalloc((s->count + 1) * sizeof(*(s->command)), GFP_KDB);
650         if (!s->command) {
651                 kdb_printf("Could not allocate new kdb_defcmd table for %s\n",
652                            cmdstr);
653                 s->usable = 0;
654                 return KDB_NOTIMP;
655         }
656         memcpy(s->command, save_command, s->count * sizeof(*(s->command)));
657         s->command[s->count++] = kdb_strdup(cmdstr, GFP_KDB);
658         kfree(save_command);
659         return 0;
660 }
661
662 static int kdb_defcmd(int argc, const char **argv)
663 {
664         struct defcmd_set *save_defcmd_set = defcmd_set, *s;
665         if (defcmd_in_progress) {
666                 kdb_printf("kdb: nested defcmd detected, assuming missing "
667                            "endefcmd\n");
668                 kdb_defcmd2("endefcmd", "endefcmd");
669         }
670         if (argc == 0) {
671                 int i;
672                 for (s = defcmd_set; s < defcmd_set + defcmd_set_count; ++s) {
673                         kdb_printf("defcmd %s \"%s\" \"%s\"\n", s->name,
674                                    s->usage, s->help);
675                         for (i = 0; i < s->count; ++i)
676                                 kdb_printf("%s", s->command[i]);
677                         kdb_printf("endefcmd\n");
678                 }
679                 return 0;
680         }
681         if (argc != 3)
682                 return KDB_ARGCOUNT;
683         defcmd_set = kmalloc((defcmd_set_count + 1) * sizeof(*defcmd_set),
684                              GFP_KDB);
685         if (!defcmd_set) {
686                 kdb_printf("Could not allocate new defcmd_set entry for %s\n",
687                            argv[1]);
688                 defcmd_set = save_defcmd_set;
689                 return KDB_NOTIMP;
690         }
691         memcpy(defcmd_set, save_defcmd_set,
692                defcmd_set_count * sizeof(*defcmd_set));
693         kfree(save_defcmd_set);
694         s = defcmd_set + defcmd_set_count;
695         memset(s, 0, sizeof(*s));
696         s->usable = 1;
697         s->name = kdb_strdup(argv[1], GFP_KDB);
698         s->usage = kdb_strdup(argv[2], GFP_KDB);
699         s->help = kdb_strdup(argv[3], GFP_KDB);
700         if (s->usage[0] == '"') {
701                 strcpy(s->usage, s->usage+1);
702                 s->usage[strlen(s->usage)-1] = '\0';
703         }
704         if (s->help[0] == '"') {
705                 strcpy(s->help, s->help+1);
706                 s->help[strlen(s->help)-1] = '\0';
707         }
708         ++defcmd_set_count;
709         defcmd_in_progress = 1;
710         return 0;
711 }
712
713 /*
714  * kdb_exec_defcmd - Execute the set of commands associated with this
715  *      defcmd name.
716  * Inputs:
717  *      argc    argument count
718  *      argv    argument vector
719  * Returns:
720  *      zero for success, a kdb diagnostic if error
721  */
722 static int kdb_exec_defcmd(int argc, const char **argv)
723 {
724         int i, ret;
725         struct defcmd_set *s;
726         if (argc != 0)
727                 return KDB_ARGCOUNT;
728         for (s = defcmd_set, i = 0; i < defcmd_set_count; ++i, ++s) {
729                 if (strcmp(s->name, argv[0]) == 0)
730                         break;
731         }
732         if (i == defcmd_set_count) {
733                 kdb_printf("kdb_exec_defcmd: could not find commands for %s\n",
734                            argv[0]);
735                 return KDB_NOTIMP;
736         }
737         for (i = 0; i < s->count; ++i) {
738                 /* Recursive use of kdb_parse, do not use argv after
739                  * this point */
740                 argv = NULL;
741                 kdb_printf("[%s]kdb> %s\n", s->name, s->command[i]);
742                 ret = kdb_parse(s->command[i]);
743                 if (ret)
744                         return ret;
745         }
746         return 0;
747 }
748
749 /* Command history */
750 #define KDB_CMD_HISTORY_COUNT   32
751 #define CMD_BUFLEN              200     /* kdb_printf: max printline
752                                          * size == 256 */
753 static unsigned int cmd_head, cmd_tail;
754 static unsigned int cmdptr;
755 static char cmd_hist[KDB_CMD_HISTORY_COUNT][CMD_BUFLEN];
756 static char cmd_cur[CMD_BUFLEN];
757
758 /*
759  * The "str" argument may point to something like  | grep xyz
760  */
761 static void parse_grep(const char *str)
762 {
763         int     len;
764         char    *cp = (char *)str, *cp2;
765
766         /* sanity check: we should have been called with the \ first */
767         if (*cp != '|')
768                 return;
769         cp++;
770         while (isspace(*cp))
771                 cp++;
772         if (strncmp(cp, "grep ", 5)) {
773                 kdb_printf("invalid 'pipe', see grephelp\n");
774                 return;
775         }
776         cp += 5;
777         while (isspace(*cp))
778                 cp++;
779         cp2 = strchr(cp, '\n');
780         if (cp2)
781                 *cp2 = '\0'; /* remove the trailing newline */
782         len = strlen(cp);
783         if (len == 0) {
784                 kdb_printf("invalid 'pipe', see grephelp\n");
785                 return;
786         }
787         /* now cp points to a nonzero length search string */
788         if (*cp == '"') {
789                 /* allow it be "x y z" by removing the "'s - there must
790                    be two of them */
791                 cp++;
792                 cp2 = strchr(cp, '"');
793                 if (!cp2) {
794                         kdb_printf("invalid quoted string, see grephelp\n");
795                         return;
796                 }
797                 *cp2 = '\0'; /* end the string where the 2nd " was */
798         }
799         kdb_grep_leading = 0;
800         if (*cp == '^') {
801                 kdb_grep_leading = 1;
802                 cp++;
803         }
804         len = strlen(cp);
805         kdb_grep_trailing = 0;
806         if (*(cp+len-1) == '$') {
807                 kdb_grep_trailing = 1;
808                 *(cp+len-1) = '\0';
809         }
810         len = strlen(cp);
811         if (!len)
812                 return;
813         if (len >= GREP_LEN) {
814                 kdb_printf("search string too long\n");
815                 return;
816         }
817         strcpy(kdb_grep_string, cp);
818         kdb_grepping_flag++;
819         return;
820 }
821
822 /*
823  * kdb_parse - Parse the command line, search the command table for a
824  *      matching command and invoke the command function.  This
825  *      function may be called recursively, if it is, the second call
826  *      will overwrite argv and cbuf.  It is the caller's
827  *      responsibility to save their argv if they recursively call
828  *      kdb_parse().
829  * Parameters:
830  *      cmdstr  The input command line to be parsed.
831  *      regs    The registers at the time kdb was entered.
832  * Returns:
833  *      Zero for success, a kdb diagnostic if failure.
834  * Remarks:
835  *      Limited to 20 tokens.
836  *
837  *      Real rudimentary tokenization. Basically only whitespace
838  *      is considered a token delimeter (but special consideration
839  *      is taken of the '=' sign as used by the 'set' command).
840  *
841  *      The algorithm used to tokenize the input string relies on
842  *      there being at least one whitespace (or otherwise useless)
843  *      character between tokens as the character immediately following
844  *      the token is altered in-place to a null-byte to terminate the
845  *      token string.
846  */
847
848 #define MAXARGC 20
849
850 int kdb_parse(const char *cmdstr)
851 {
852         static char *argv[MAXARGC];
853         static int argc;
854         static char cbuf[CMD_BUFLEN+2];
855         char *cp;
856         char *cpp, quoted;
857         kdbtab_t *tp;
858         int i, escaped, ignore_errors = 0, check_grep;
859
860         /*
861          * First tokenize the command string.
862          */
863         cp = (char *)cmdstr;
864         kdb_grepping_flag = check_grep = 0;
865
866         if (KDB_FLAG(CMD_INTERRUPT)) {
867                 /* Previous command was interrupted, newline must not
868                  * repeat the command */
869                 KDB_FLAG_CLEAR(CMD_INTERRUPT);
870                 KDB_STATE_SET(PAGER);
871                 argc = 0;       /* no repeat */
872         }
873
874         if (*cp != '\n' && *cp != '\0') {
875                 argc = 0;
876                 cpp = cbuf;
877                 while (*cp) {
878                         /* skip whitespace */
879                         while (isspace(*cp))
880                                 cp++;
881                         if ((*cp == '\0') || (*cp == '\n') ||
882                             (*cp == '#' && !defcmd_in_progress))
883                                 break;
884                         /* special case: check for | grep pattern */
885                         if (*cp == '|') {
886                                 check_grep++;
887                                 break;
888                         }
889                         if (cpp >= cbuf + CMD_BUFLEN) {
890                                 kdb_printf("kdb_parse: command buffer "
891                                            "overflow, command ignored\n%s\n",
892                                            cmdstr);
893                                 return KDB_NOTFOUND;
894                         }
895                         if (argc >= MAXARGC - 1) {
896                                 kdb_printf("kdb_parse: too many arguments, "
897                                            "command ignored\n%s\n", cmdstr);
898                                 return KDB_NOTFOUND;
899                         }
900                         argv[argc++] = cpp;
901                         escaped = 0;
902                         quoted = '\0';
903                         /* Copy to next unquoted and unescaped
904                          * whitespace or '=' */
905                         while (*cp && *cp != '\n' &&
906                                (escaped || quoted || !isspace(*cp))) {
907                                 if (cpp >= cbuf + CMD_BUFLEN)
908                                         break;
909                                 if (escaped) {
910                                         escaped = 0;
911                                         *cpp++ = *cp++;
912                                         continue;
913                                 }
914                                 if (*cp == '\\') {
915                                         escaped = 1;
916                                         ++cp;
917                                         continue;
918                                 }
919                                 if (*cp == quoted)
920                                         quoted = '\0';
921                                 else if (*cp == '\'' || *cp == '"')
922                                         quoted = *cp;
923                                 *cpp = *cp++;
924                                 if (*cpp == '=' && !quoted)
925                                         break;
926                                 ++cpp;
927                         }
928                         *cpp++ = '\0';  /* Squash a ws or '=' character */
929                 }
930         }
931         if (!argc)
932                 return 0;
933         if (check_grep)
934                 parse_grep(cp);
935         if (defcmd_in_progress) {
936                 int result = kdb_defcmd2(cmdstr, argv[0]);
937                 if (!defcmd_in_progress) {
938                         argc = 0;       /* avoid repeat on endefcmd */
939                         *(argv[0]) = '\0';
940                 }
941                 return result;
942         }
943         if (argv[0][0] == '-' && argv[0][1] &&
944             (argv[0][1] < '0' || argv[0][1] > '9')) {
945                 ignore_errors = 1;
946                 ++argv[0];
947         }
948
949         for_each_kdbcmd(tp, i) {
950                 if (tp->cmd_name) {
951                         /*
952                          * If this command is allowed to be abbreviated,
953                          * check to see if this is it.
954                          */
955
956                         if (tp->cmd_minlen
957                          && (strlen(argv[0]) <= tp->cmd_minlen)) {
958                                 if (strncmp(argv[0],
959                                             tp->cmd_name,
960                                             tp->cmd_minlen) == 0) {
961                                         break;
962                                 }
963                         }
964
965                         if (strcmp(argv[0], tp->cmd_name) == 0)
966                                 break;
967                 }
968         }
969
970         /*
971          * If we don't find a command by this name, see if the first
972          * few characters of this match any of the known commands.
973          * e.g., md1c20 should match md.
974          */
975         if (i == kdb_max_commands) {
976                 for_each_kdbcmd(tp, i) {
977                         if (tp->cmd_name) {
978                                 if (strncmp(argv[0],
979                                             tp->cmd_name,
980                                             strlen(tp->cmd_name)) == 0) {
981                                         break;
982                                 }
983                         }
984                 }
985         }
986
987         if (i < kdb_max_commands) {
988                 int result;
989                 KDB_STATE_SET(CMD);
990                 result = (*tp->cmd_func)(argc-1, (const char **)argv);
991                 if (result && ignore_errors && result > KDB_CMD_GO)
992                         result = 0;
993                 KDB_STATE_CLEAR(CMD);
994                 switch (tp->cmd_repeat) {
995                 case KDB_REPEAT_NONE:
996                         argc = 0;
997                         if (argv[0])
998                                 *(argv[0]) = '\0';
999                         break;
1000                 case KDB_REPEAT_NO_ARGS:
1001                         argc = 1;
1002                         if (argv[1])
1003                                 *(argv[1]) = '\0';
1004                         break;
1005                 case KDB_REPEAT_WITH_ARGS:
1006                         break;
1007                 }
1008                 return result;
1009         }
1010
1011         /*
1012          * If the input with which we were presented does not
1013          * map to an existing command, attempt to parse it as an
1014          * address argument and display the result.   Useful for
1015          * obtaining the address of a variable, or the nearest symbol
1016          * to an address contained in a register.
1017          */
1018         {
1019                 unsigned long value;
1020                 char *name = NULL;
1021                 long offset;
1022                 int nextarg = 0;
1023
1024                 if (kdbgetaddrarg(0, (const char **)argv, &nextarg,
1025                                   &value, &offset, &name)) {
1026                         return KDB_NOTFOUND;
1027                 }
1028
1029                 kdb_printf("%s = ", argv[0]);
1030                 kdb_symbol_print(value, NULL, KDB_SP_DEFAULT);
1031                 kdb_printf("\n");
1032                 return 0;
1033         }
1034 }
1035
1036
1037 static int handle_ctrl_cmd(char *cmd)
1038 {
1039 #define CTRL_P  16
1040 #define CTRL_N  14
1041
1042         /* initial situation */
1043         if (cmd_head == cmd_tail)
1044                 return 0;
1045         switch (*cmd) {
1046         case CTRL_P:
1047                 if (cmdptr != cmd_tail)
1048                         cmdptr = (cmdptr-1) % KDB_CMD_HISTORY_COUNT;
1049                 strncpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
1050                 return 1;
1051         case CTRL_N:
1052                 if (cmdptr != cmd_head)
1053                         cmdptr = (cmdptr+1) % KDB_CMD_HISTORY_COUNT;
1054                 strncpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
1055                 return 1;
1056         }
1057         return 0;
1058 }
1059
1060 /*
1061  * kdb_reboot - This function implements the 'reboot' command.  Reboot
1062  *      the system immediately, or loop for ever on failure.
1063  */
1064 static int kdb_reboot(int argc, const char **argv)
1065 {
1066         emergency_restart();
1067         kdb_printf("Hmm, kdb_reboot did not reboot, spinning here\n");
1068         while (1)
1069                 cpu_relax();
1070         /* NOTREACHED */
1071         return 0;
1072 }
1073
1074 static void kdb_dumpregs(struct pt_regs *regs)
1075 {
1076         int old_lvl = console_loglevel;
1077         console_loglevel = 15;
1078         kdb_trap_printk++;
1079         show_regs(regs);
1080         kdb_trap_printk--;
1081         kdb_printf("\n");
1082         console_loglevel = old_lvl;
1083 }
1084
1085 void kdb_set_current_task(struct task_struct *p)
1086 {
1087         kdb_current_task = p;
1088
1089         if (kdb_task_has_cpu(p)) {
1090                 kdb_current_regs = KDB_TSKREGS(kdb_process_cpu(p));
1091                 return;
1092         }
1093         kdb_current_regs = NULL;
1094 }
1095
1096 /*
1097  * kdb_local - The main code for kdb.  This routine is invoked on a
1098  *      specific processor, it is not global.  The main kdb() routine
1099  *      ensures that only one processor at a time is in this routine.
1100  *      This code is called with the real reason code on the first
1101  *      entry to a kdb session, thereafter it is called with reason
1102  *      SWITCH, even if the user goes back to the original cpu.
1103  * Inputs:
1104  *      reason          The reason KDB was invoked
1105  *      error           The hardware-defined error code
1106  *      regs            The exception frame at time of fault/breakpoint.
1107  *      db_result       Result code from the break or debug point.
1108  * Returns:
1109  *      0       KDB was invoked for an event which it wasn't responsible
1110  *      1       KDB handled the event for which it was invoked.
1111  *      KDB_CMD_GO      User typed 'go'.
1112  *      KDB_CMD_CPU     User switched to another cpu.
1113  *      KDB_CMD_SS      Single step.
1114  *      KDB_CMD_SSB     Single step until branch.
1115  */
1116 static int kdb_local(kdb_reason_t reason, int error, struct pt_regs *regs,
1117                      kdb_dbtrap_t db_result)
1118 {
1119         char *cmdbuf;
1120         int diag;
1121         struct task_struct *kdb_current =
1122                 kdb_curr_task(raw_smp_processor_id());
1123
1124         KDB_DEBUG_STATE("kdb_local 1", reason);
1125         kdb_go_count = 0;
1126         if (reason == KDB_REASON_DEBUG) {
1127                 /* special case below */
1128         } else {
1129                 kdb_printf("\nEntering kdb (current=0x%p, pid %d) ",
1130                            kdb_current, kdb_current->pid);
1131 #if defined(CONFIG_SMP)
1132                 kdb_printf("on processor %d ", raw_smp_processor_id());
1133 #endif
1134         }
1135
1136         switch (reason) {
1137         case KDB_REASON_DEBUG:
1138         {
1139                 /*
1140                  * If re-entering kdb after a single step
1141                  * command, don't print the message.
1142                  */
1143                 switch (db_result) {
1144                 case KDB_DB_BPT:
1145                         kdb_printf("\nEntering kdb (0x%p, pid %d) ",
1146                                    kdb_current, kdb_current->pid);
1147 #if defined(CONFIG_SMP)
1148                         kdb_printf("on processor %d ", raw_smp_processor_id());
1149 #endif
1150                         kdb_printf("due to Debug @ " kdb_machreg_fmt "\n",
1151                                    instruction_pointer(regs));
1152                         break;
1153                 case KDB_DB_SSB:
1154                         /*
1155                          * In the midst of ssb command. Just return.
1156                          */
1157                         KDB_DEBUG_STATE("kdb_local 3", reason);
1158                         return KDB_CMD_SSB;     /* Continue with SSB command */
1159
1160                         break;
1161                 case KDB_DB_SS:
1162                         break;
1163                 case KDB_DB_SSBPT:
1164                         KDB_DEBUG_STATE("kdb_local 4", reason);
1165                         return 1;       /* kdba_db_trap did the work */
1166                 default:
1167                         kdb_printf("kdb: Bad result from kdba_db_trap: %d\n",
1168                                    db_result);
1169                         break;
1170                 }
1171
1172         }
1173                 break;
1174         case KDB_REASON_ENTER:
1175                 if (KDB_STATE(KEYBOARD))
1176                         kdb_printf("due to Keyboard Entry\n");
1177                 else
1178                         kdb_printf("due to KDB_ENTER()\n");
1179                 break;
1180         case KDB_REASON_KEYBOARD:
1181                 KDB_STATE_SET(KEYBOARD);
1182                 kdb_printf("due to Keyboard Entry\n");
1183                 break;
1184         case KDB_REASON_ENTER_SLAVE:
1185                 /* drop through, slaves only get released via cpu switch */
1186         case KDB_REASON_SWITCH:
1187                 kdb_printf("due to cpu switch\n");
1188                 break;
1189         case KDB_REASON_OOPS:
1190                 kdb_printf("Oops: %s\n", kdb_diemsg);
1191                 kdb_printf("due to oops @ " kdb_machreg_fmt "\n",
1192                            instruction_pointer(regs));
1193                 kdb_dumpregs(regs);
1194                 break;
1195         case KDB_REASON_NMI:
1196                 kdb_printf("due to NonMaskable Interrupt @ "
1197                            kdb_machreg_fmt "\n",
1198                            instruction_pointer(regs));
1199                 kdb_dumpregs(regs);
1200                 break;
1201         case KDB_REASON_SSTEP:
1202         case KDB_REASON_BREAK:
1203                 kdb_printf("due to %s @ " kdb_machreg_fmt "\n",
1204                            reason == KDB_REASON_BREAK ?
1205                            "Breakpoint" : "SS trap", instruction_pointer(regs));
1206                 /*
1207                  * Determine if this breakpoint is one that we
1208                  * are interested in.
1209                  */
1210                 if (db_result != KDB_DB_BPT) {
1211                         kdb_printf("kdb: error return from kdba_bp_trap: %d\n",
1212                                    db_result);
1213                         KDB_DEBUG_STATE("kdb_local 6", reason);
1214                         return 0;       /* Not for us, dismiss it */
1215                 }
1216                 break;
1217         case KDB_REASON_RECURSE:
1218                 kdb_printf("due to Recursion @ " kdb_machreg_fmt "\n",
1219                            instruction_pointer(regs));
1220                 break;
1221         default:
1222                 kdb_printf("kdb: unexpected reason code: %d\n", reason);
1223                 KDB_DEBUG_STATE("kdb_local 8", reason);
1224                 return 0;       /* Not for us, dismiss it */
1225         }
1226
1227         while (1) {
1228                 /*
1229                  * Initialize pager context.
1230                  */
1231                 kdb_nextline = 1;
1232                 KDB_STATE_CLEAR(SUPPRESS);
1233
1234                 cmdbuf = cmd_cur;
1235                 *cmdbuf = '\0';
1236                 *(cmd_hist[cmd_head]) = '\0';
1237
1238                 if (KDB_FLAG(ONLY_DO_DUMP)) {
1239                         /* kdb is off but a catastrophic error requires a dump.
1240                          * Take the dump and reboot.
1241                          * Turn on logging so the kdb output appears in the log
1242                          * buffer in the dump.
1243                          */
1244                         const char *setargs[] = { "set", "LOGGING", "1" };
1245                         kdb_set(2, setargs);
1246                         kdb_reboot(0, NULL);
1247                         /*NOTREACHED*/
1248                 }
1249
1250 do_full_getstr:
1251 #if defined(CONFIG_SMP)
1252                 snprintf(kdb_prompt_str, CMD_BUFLEN, kdbgetenv("PROMPT"),
1253                          raw_smp_processor_id());
1254 #else
1255                 snprintf(kdb_prompt_str, CMD_BUFLEN, kdbgetenv("PROMPT"));
1256 #endif
1257                 if (defcmd_in_progress)
1258                         strncat(kdb_prompt_str, "[defcmd]", CMD_BUFLEN);
1259
1260                 /*
1261                  * Fetch command from keyboard
1262                  */
1263                 cmdbuf = kdb_getstr(cmdbuf, CMD_BUFLEN, kdb_prompt_str);
1264                 if (*cmdbuf != '\n') {
1265                         if (*cmdbuf < 32) {
1266                                 if (cmdptr == cmd_head) {
1267                                         strncpy(cmd_hist[cmd_head], cmd_cur,
1268                                                 CMD_BUFLEN);
1269                                         *(cmd_hist[cmd_head] +
1270                                           strlen(cmd_hist[cmd_head])-1) = '\0';
1271                                 }
1272                                 if (!handle_ctrl_cmd(cmdbuf))
1273                                         *(cmd_cur+strlen(cmd_cur)-1) = '\0';
1274                                 cmdbuf = cmd_cur;
1275                                 goto do_full_getstr;
1276                         } else {
1277                                 strncpy(cmd_hist[cmd_head], cmd_cur,
1278                                         CMD_BUFLEN);
1279                         }
1280
1281                         cmd_head = (cmd_head+1) % KDB_CMD_HISTORY_COUNT;
1282                         if (cmd_head == cmd_tail)
1283                                 cmd_tail = (cmd_tail+1) % KDB_CMD_HISTORY_COUNT;
1284                 }
1285
1286                 cmdptr = cmd_head;
1287                 diag = kdb_parse(cmdbuf);
1288                 if (diag == KDB_NOTFOUND) {
1289                         kdb_printf("Unknown kdb command: '%s'\n", cmdbuf);
1290                         diag = 0;
1291                 }
1292                 if (diag == KDB_CMD_GO
1293                  || diag == KDB_CMD_CPU
1294                  || diag == KDB_CMD_SS
1295                  || diag == KDB_CMD_SSB
1296                  || diag == KDB_CMD_KGDB)
1297                         break;
1298
1299                 if (diag)
1300                         kdb_cmderror(diag);
1301         }
1302         KDB_DEBUG_STATE("kdb_local 9", diag);
1303         return diag;
1304 }
1305
1306
1307 /*
1308  * kdb_print_state - Print the state data for the current processor
1309  *      for debugging.
1310  * Inputs:
1311  *      text            Identifies the debug point
1312  *      value           Any integer value to be printed, e.g. reason code.
1313  */
1314 void kdb_print_state(const char *text, int value)
1315 {
1316         kdb_printf("state: %s cpu %d value %d initial %d state %x\n",
1317                    text, raw_smp_processor_id(), value, kdb_initial_cpu,
1318                    kdb_state);
1319 }
1320
1321 /*
1322  * kdb_main_loop - After initial setup and assignment of the
1323  *      controlling cpu, all cpus are in this loop.  One cpu is in
1324  *      control and will issue the kdb prompt, the others will spin
1325  *      until 'go' or cpu switch.
1326  *
1327  *      To get a consistent view of the kernel stacks for all
1328  *      processes, this routine is invoked from the main kdb code via
1329  *      an architecture specific routine.  kdba_main_loop is
1330  *      responsible for making the kernel stacks consistent for all
1331  *      processes, there should be no difference between a blocked
1332  *      process and a running process as far as kdb is concerned.
1333  * Inputs:
1334  *      reason          The reason KDB was invoked
1335  *      error           The hardware-defined error code
1336  *      reason2         kdb's current reason code.
1337  *                      Initially error but can change
1338  *                      acording to kdb state.
1339  *      db_result       Result code from break or debug point.
1340  *      regs            The exception frame at time of fault/breakpoint.
1341  *                      should always be valid.
1342  * Returns:
1343  *      0       KDB was invoked for an event which it wasn't responsible
1344  *      1       KDB handled the event for which it was invoked.
1345  */
1346 int kdb_main_loop(kdb_reason_t reason, kdb_reason_t reason2, int error,
1347               kdb_dbtrap_t db_result, struct pt_regs *regs)
1348 {
1349         int result = 1;
1350         /* Stay in kdb() until 'go', 'ss[b]' or an error */
1351         while (1) {
1352                 /*
1353                  * All processors except the one that is in control
1354                  * will spin here.
1355                  */
1356                 KDB_DEBUG_STATE("kdb_main_loop 1", reason);
1357                 while (KDB_STATE(HOLD_CPU)) {
1358                         /* state KDB is turned off by kdb_cpu to see if the
1359                          * other cpus are still live, each cpu in this loop
1360                          * turns it back on.
1361                          */
1362                         if (!KDB_STATE(KDB))
1363                                 KDB_STATE_SET(KDB);
1364                 }
1365
1366                 KDB_STATE_CLEAR(SUPPRESS);
1367                 KDB_DEBUG_STATE("kdb_main_loop 2", reason);
1368                 if (KDB_STATE(LEAVING))
1369                         break;  /* Another cpu said 'go' */
1370                 /* Still using kdb, this processor is in control */
1371                 result = kdb_local(reason2, error, regs, db_result);
1372                 KDB_DEBUG_STATE("kdb_main_loop 3", result);
1373
1374                 if (result == KDB_CMD_CPU)
1375                         break;
1376
1377                 if (result == KDB_CMD_SS) {
1378                         KDB_STATE_SET(DOING_SS);
1379                         break;
1380                 }
1381
1382                 if (result == KDB_CMD_SSB) {
1383                         KDB_STATE_SET(DOING_SS);
1384                         KDB_STATE_SET(DOING_SSB);
1385                         break;
1386                 }
1387
1388                 if (result == KDB_CMD_KGDB) {
1389                         if (!(KDB_STATE(DOING_KGDB) || KDB_STATE(DOING_KGDB2)))
1390                                 kdb_printf("Entering please attach debugger "
1391                                            "or use $D#44+ or $3#33\n");
1392                         break;
1393                 }
1394                 if (result && result != 1 && result != KDB_CMD_GO)
1395                         kdb_printf("\nUnexpected kdb_local return code %d\n",
1396                                    result);
1397                 KDB_DEBUG_STATE("kdb_main_loop 4", reason);
1398                 break;
1399         }
1400         if (KDB_STATE(DOING_SS))
1401                 KDB_STATE_CLEAR(SSBPT);
1402
1403         return result;
1404 }
1405
1406 /*
1407  * kdb_mdr - This function implements the guts of the 'mdr', memory
1408  * read command.
1409  *      mdr  <addr arg>,<byte count>
1410  * Inputs:
1411  *      addr    Start address
1412  *      count   Number of bytes
1413  * Returns:
1414  *      Always 0.  Any errors are detected and printed by kdb_getarea.
1415  */
1416 static int kdb_mdr(unsigned long addr, unsigned int count)
1417 {
1418         unsigned char c;
1419         while (count--) {
1420                 if (kdb_getarea(c, addr))
1421                         return 0;
1422                 kdb_printf("%02x", c);
1423                 addr++;
1424         }
1425         kdb_printf("\n");
1426         return 0;
1427 }
1428
1429 /*
1430  * kdb_md - This function implements the 'md', 'md1', 'md2', 'md4',
1431  *      'md8' 'mdr' and 'mds' commands.
1432  *
1433  *      md|mds  [<addr arg> [<line count> [<radix>]]]
1434  *      mdWcN   [<addr arg> [<line count> [<radix>]]]
1435  *              where W = is the width (1, 2, 4 or 8) and N is the count.
1436  *              for eg., md1c20 reads 20 bytes, 1 at a time.
1437  *      mdr  <addr arg>,<byte count>
1438  */
1439 static void kdb_md_line(const char *fmtstr, unsigned long addr,
1440                         int symbolic, int nosect, int bytesperword,
1441                         int num, int repeat, int phys)
1442 {
1443         /* print just one line of data */
1444         kdb_symtab_t symtab;
1445         char cbuf[32];
1446         char *c = cbuf;
1447         int i;
1448         unsigned long word;
1449
1450         memset(cbuf, '\0', sizeof(cbuf));
1451         if (phys)
1452                 kdb_printf("phys " kdb_machreg_fmt0 " ", addr);
1453         else
1454                 kdb_printf(kdb_machreg_fmt0 " ", addr);
1455
1456         for (i = 0; i < num && repeat--; i++) {
1457                 if (phys) {
1458                         if (kdb_getphysword(&word, addr, bytesperword))
1459                                 break;
1460                 } else if (kdb_getword(&word, addr, bytesperword))
1461                         break;
1462                 kdb_printf(fmtstr, word);
1463                 if (symbolic)
1464                         kdbnearsym(word, &symtab);
1465                 else
1466                         memset(&symtab, 0, sizeof(symtab));
1467                 if (symtab.sym_name) {
1468                         kdb_symbol_print(word, &symtab, 0);
1469                         if (!nosect) {
1470                                 kdb_printf("\n");
1471                                 kdb_printf("                       %s %s "
1472                                            kdb_machreg_fmt " "
1473                                            kdb_machreg_fmt " "
1474                                            kdb_machreg_fmt, symtab.mod_name,
1475                                            symtab.sec_name, symtab.sec_start,
1476                                            symtab.sym_start, symtab.sym_end);
1477                         }
1478                         addr += bytesperword;
1479                 } else {
1480                         union {
1481                                 u64 word;
1482                                 unsigned char c[8];
1483                         } wc;
1484                         unsigned char *cp;
1485 #ifdef  __BIG_ENDIAN
1486                         cp = wc.c + 8 - bytesperword;
1487 #else
1488                         cp = wc.c;
1489 #endif
1490                         wc.word = word;
1491 #define printable_char(c) \
1492         ({unsigned char __c = c; isascii(__c) && isprint(__c) ? __c : '.'; })
1493                         switch (bytesperword) {
1494                         case 8:
1495                                 *c++ = printable_char(*cp++);
1496                                 *c++ = printable_char(*cp++);
1497                                 *c++ = printable_char(*cp++);
1498                                 *c++ = printable_char(*cp++);
1499                                 addr += 4;
1500                         case 4:
1501                                 *c++ = printable_char(*cp++);
1502                                 *c++ = printable_char(*cp++);
1503                                 addr += 2;
1504                         case 2:
1505                                 *c++ = printable_char(*cp++);
1506                                 addr++;
1507                         case 1:
1508                                 *c++ = printable_char(*cp++);
1509                                 addr++;
1510                                 break;
1511                         }
1512 #undef printable_char
1513                 }
1514         }
1515         kdb_printf("%*s %s\n", (int)((num-i)*(2*bytesperword + 1)+1),
1516                    " ", cbuf);
1517 }
1518
1519 static int kdb_md(int argc, const char **argv)
1520 {
1521         static unsigned long last_addr;
1522         static int last_radix, last_bytesperword, last_repeat;
1523         int radix = 16, mdcount = 8, bytesperword = KDB_WORD_SIZE, repeat;
1524         int nosect = 0;
1525         char fmtchar, fmtstr[64];
1526         unsigned long addr;
1527         unsigned long word;
1528         long offset = 0;
1529         int symbolic = 0;
1530         int valid = 0;
1531         int phys = 0;
1532
1533         kdbgetintenv("MDCOUNT", &mdcount);
1534         kdbgetintenv("RADIX", &radix);
1535         kdbgetintenv("BYTESPERWORD", &bytesperword);
1536
1537         /* Assume 'md <addr>' and start with environment values */
1538         repeat = mdcount * 16 / bytesperword;
1539
1540         if (strcmp(argv[0], "mdr") == 0) {
1541                 if (argc != 2)
1542                         return KDB_ARGCOUNT;
1543                 valid = 1;
1544         } else if (isdigit(argv[0][2])) {
1545                 bytesperword = (int)(argv[0][2] - '0');
1546                 if (bytesperword == 0) {
1547                         bytesperword = last_bytesperword;
1548                         if (bytesperword == 0)
1549                                 bytesperword = 4;
1550                 }
1551                 last_bytesperword = bytesperword;
1552                 repeat = mdcount * 16 / bytesperword;
1553                 if (!argv[0][3])
1554                         valid = 1;
1555                 else if (argv[0][3] == 'c' && argv[0][4]) {
1556                         char *p;
1557                         repeat = simple_strtoul(argv[0] + 4, &p, 10);
1558                         mdcount = ((repeat * bytesperword) + 15) / 16;
1559                         valid = !*p;
1560                 }
1561                 last_repeat = repeat;
1562         } else if (strcmp(argv[0], "md") == 0)
1563                 valid = 1;
1564         else if (strcmp(argv[0], "mds") == 0)
1565                 valid = 1;
1566         else if (strcmp(argv[0], "mdp") == 0) {
1567                 phys = valid = 1;
1568         }
1569         if (!valid)
1570                 return KDB_NOTFOUND;
1571
1572         if (argc == 0) {
1573                 if (last_addr == 0)
1574                         return KDB_ARGCOUNT;
1575                 addr = last_addr;
1576                 radix = last_radix;
1577                 bytesperword = last_bytesperword;
1578                 repeat = last_repeat;
1579                 mdcount = ((repeat * bytesperword) + 15) / 16;
1580         }
1581
1582         if (argc) {
1583                 unsigned long val;
1584                 int diag, nextarg = 1;
1585                 diag = kdbgetaddrarg(argc, argv, &nextarg, &addr,
1586                                      &offset, NULL);
1587                 if (diag)
1588                         return diag;
1589                 if (argc > nextarg+2)
1590                         return KDB_ARGCOUNT;
1591
1592                 if (argc >= nextarg) {
1593                         diag = kdbgetularg(argv[nextarg], &val);
1594                         if (!diag) {
1595                                 mdcount = (int) val;
1596                                 repeat = mdcount * 16 / bytesperword;
1597                         }
1598                 }
1599                 if (argc >= nextarg+1) {
1600                         diag = kdbgetularg(argv[nextarg+1], &val);
1601                         if (!diag)
1602                                 radix = (int) val;
1603                 }
1604         }
1605
1606         if (strcmp(argv[0], "mdr") == 0)
1607                 return kdb_mdr(addr, mdcount);
1608
1609         switch (radix) {
1610         case 10:
1611                 fmtchar = 'd';
1612                 break;
1613         case 16:
1614                 fmtchar = 'x';
1615                 break;
1616         case 8:
1617                 fmtchar = 'o';
1618                 break;
1619         default:
1620                 return KDB_BADRADIX;
1621         }
1622
1623         last_radix = radix;
1624
1625         if (bytesperword > KDB_WORD_SIZE)
1626                 return KDB_BADWIDTH;
1627
1628         switch (bytesperword) {
1629         case 8:
1630                 sprintf(fmtstr, "%%16.16l%c ", fmtchar);
1631                 break;
1632         case 4:
1633                 sprintf(fmtstr, "%%8.8l%c ", fmtchar);
1634                 break;
1635         case 2:
1636                 sprintf(fmtstr, "%%4.4l%c ", fmtchar);
1637                 break;
1638         case 1:
1639                 sprintf(fmtstr, "%%2.2l%c ", fmtchar);
1640                 break;
1641         default:
1642                 return KDB_BADWIDTH;
1643         }
1644
1645         last_repeat = repeat;
1646         last_bytesperword = bytesperword;
1647
1648         if (strcmp(argv[0], "mds") == 0) {
1649                 symbolic = 1;
1650                 /* Do not save these changes as last_*, they are temporary mds
1651                  * overrides.
1652                  */
1653                 bytesperword = KDB_WORD_SIZE;
1654                 repeat = mdcount;
1655                 kdbgetintenv("NOSECT", &nosect);
1656         }
1657
1658         /* Round address down modulo BYTESPERWORD */
1659
1660         addr &= ~(bytesperword-1);
1661
1662         while (repeat > 0) {
1663                 unsigned long a;
1664                 int n, z, num = (symbolic ? 1 : (16 / bytesperword));
1665
1666                 if (KDB_FLAG(CMD_INTERRUPT))
1667                         return 0;
1668                 for (a = addr, z = 0; z < repeat; a += bytesperword, ++z) {
1669                         if (phys) {
1670                                 if (kdb_getphysword(&word, a, bytesperword)
1671                                                 || word)
1672                                         break;
1673                         } else if (kdb_getword(&word, a, bytesperword) || word)
1674                                 break;
1675                 }
1676                 n = min(num, repeat);
1677                 kdb_md_line(fmtstr, addr, symbolic, nosect, bytesperword,
1678                             num, repeat, phys);
1679                 addr += bytesperword * n;
1680                 repeat -= n;
1681                 z = (z + num - 1) / num;
1682                 if (z > 2) {
1683                         int s = num * (z-2);
1684                         kdb_printf(kdb_machreg_fmt0 "-" kdb_machreg_fmt0
1685                                    " zero suppressed\n",
1686                                 addr, addr + bytesperword * s - 1);
1687                         addr += bytesperword * s;
1688                         repeat -= s;
1689                 }
1690         }
1691         last_addr = addr;
1692
1693         return 0;
1694 }
1695
1696 /*
1697  * kdb_mm - This function implements the 'mm' command.
1698  *      mm address-expression new-value
1699  * Remarks:
1700  *      mm works on machine words, mmW works on bytes.
1701  */
1702 static int kdb_mm(int argc, const char **argv)
1703 {
1704         int diag;
1705         unsigned long addr;
1706         long offset = 0;
1707         unsigned long contents;
1708         int nextarg;
1709         int width;
1710
1711         if (argv[0][2] && !isdigit(argv[0][2]))
1712                 return KDB_NOTFOUND;
1713
1714         if (argc < 2)
1715                 return KDB_ARGCOUNT;
1716
1717         nextarg = 1;
1718         diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
1719         if (diag)
1720                 return diag;
1721
1722         if (nextarg > argc)
1723                 return KDB_ARGCOUNT;
1724         diag = kdbgetaddrarg(argc, argv, &nextarg, &contents, NULL, NULL);
1725         if (diag)
1726                 return diag;
1727
1728         if (nextarg != argc + 1)
1729                 return KDB_ARGCOUNT;
1730
1731         width = argv[0][2] ? (argv[0][2] - '0') : (KDB_WORD_SIZE);
1732         diag = kdb_putword(addr, contents, width);
1733         if (diag)
1734                 return diag;
1735
1736         kdb_printf(kdb_machreg_fmt " = " kdb_machreg_fmt "\n", addr, contents);
1737
1738         return 0;
1739 }
1740
1741 /*
1742  * kdb_go - This function implements the 'go' command.
1743  *      go [address-expression]
1744  */
1745 static int kdb_go(int argc, const char **argv)
1746 {
1747         unsigned long addr;
1748         int diag;
1749         int nextarg;
1750         long offset;
1751
1752         if (argc == 1) {
1753                 if (raw_smp_processor_id() != kdb_initial_cpu) {
1754                         kdb_printf("go <address> must be issued from the "
1755                                    "initial cpu, do cpu %d first\n",
1756                                    kdb_initial_cpu);
1757                         return KDB_ARGCOUNT;
1758                 }
1759                 nextarg = 1;
1760                 diag = kdbgetaddrarg(argc, argv, &nextarg,
1761                                      &addr, &offset, NULL);
1762                 if (diag)
1763                         return diag;
1764         } else if (argc) {
1765                 return KDB_ARGCOUNT;
1766         }
1767
1768         diag = KDB_CMD_GO;
1769         if (KDB_FLAG(CATASTROPHIC)) {
1770                 kdb_printf("Catastrophic error detected\n");
1771                 kdb_printf("kdb_continue_catastrophic=%d, ",
1772                         kdb_continue_catastrophic);
1773                 if (kdb_continue_catastrophic == 0 && kdb_go_count++ == 0) {
1774                         kdb_printf("type go a second time if you really want "
1775                                    "to continue\n");
1776                         return 0;
1777                 }
1778                 if (kdb_continue_catastrophic == 2) {
1779                         kdb_printf("forcing reboot\n");
1780                         kdb_reboot(0, NULL);
1781                 }
1782                 kdb_printf("attempting to continue\n");
1783         }
1784         return diag;
1785 }
1786
1787 /*
1788  * kdb_rd - This function implements the 'rd' command.
1789  */
1790 static int kdb_rd(int argc, const char **argv)
1791 {
1792         int len = kdb_check_regs();
1793 #if DBG_MAX_REG_NUM > 0
1794         int i;
1795         char *rname;
1796         int rsize;
1797         u64 reg64;
1798         u32 reg32;
1799         u16 reg16;
1800         u8 reg8;
1801
1802         if (len)
1803                 return len;
1804
1805         for (i = 0; i < DBG_MAX_REG_NUM; i++) {
1806                 rsize = dbg_reg_def[i].size * 2;
1807                 if (rsize > 16)
1808                         rsize = 2;
1809                 if (len + strlen(dbg_reg_def[i].name) + 4 + rsize > 80) {
1810                         len = 0;
1811                         kdb_printf("\n");
1812                 }
1813                 if (len)
1814                         len += kdb_printf("  ");
1815                 switch(dbg_reg_def[i].size * 8) {
1816                 case 8:
1817                         rname = dbg_get_reg(i, &reg8, kdb_current_regs);
1818                         if (!rname)
1819                                 break;
1820                         len += kdb_printf("%s: %02x", rname, reg8);
1821                         break;
1822                 case 16:
1823                         rname = dbg_get_reg(i, &reg16, kdb_current_regs);
1824                         if (!rname)
1825                                 break;
1826                         len += kdb_printf("%s: %04x", rname, reg16);
1827                         break;
1828                 case 32:
1829                         rname = dbg_get_reg(i, &reg32, kdb_current_regs);
1830                         if (!rname)
1831                                 break;
1832                         len += kdb_printf("%s: %08x", rname, reg32);
1833                         break;
1834                 case 64:
1835                         rname = dbg_get_reg(i, &reg64, kdb_current_regs);
1836                         if (!rname)
1837                                 break;
1838                         len += kdb_printf("%s: %016llx", rname, reg64);
1839                         break;
1840                 default:
1841                         len += kdb_printf("%s: ??", dbg_reg_def[i].name);
1842                 }
1843         }
1844         kdb_printf("\n");
1845 #else
1846         if (len)
1847                 return len;
1848
1849         kdb_dumpregs(kdb_current_regs);
1850 #endif
1851         return 0;
1852 }
1853
1854 /*
1855  * kdb_rm - This function implements the 'rm' (register modify)  command.
1856  *      rm register-name new-contents
1857  * Remarks:
1858  *      Allows register modification with the same restrictions as gdb
1859  */
1860 static int kdb_rm(int argc, const char **argv)
1861 {
1862 #if DBG_MAX_REG_NUM > 0
1863         int diag;
1864         const char *rname;
1865         int i;
1866         u64 reg64;
1867         u32 reg32;
1868         u16 reg16;
1869         u8 reg8;
1870
1871         if (argc != 2)
1872                 return KDB_ARGCOUNT;
1873         /*
1874          * Allow presence or absence of leading '%' symbol.
1875          */
1876         rname = argv[1];
1877         if (*rname == '%')
1878                 rname++;
1879
1880         diag = kdbgetu64arg(argv[2], &reg64);
1881         if (diag)
1882                 return diag;
1883
1884         diag = kdb_check_regs();
1885         if (diag)
1886                 return diag;
1887
1888         diag = KDB_BADREG;
1889         for (i = 0; i < DBG_MAX_REG_NUM; i++) {
1890                 if (strcmp(rname, dbg_reg_def[i].name) == 0) {
1891                         diag = 0;
1892                         break;
1893                 }
1894         }
1895         if (!diag) {
1896                 switch(dbg_reg_def[i].size * 8) {
1897                 case 8:
1898                         reg8 = reg64;
1899                         dbg_set_reg(i, &reg8, kdb_current_regs);
1900                         break;
1901                 case 16:
1902                         reg16 = reg64;
1903                         dbg_set_reg(i, &reg16, kdb_current_regs);
1904                         break;
1905                 case 32:
1906                         reg32 = reg64;
1907                         dbg_set_reg(i, &reg32, kdb_current_regs);
1908                         break;
1909                 case 64:
1910                         dbg_set_reg(i, &reg64, kdb_current_regs);
1911                         break;
1912                 }
1913         }
1914         return diag;
1915 #else
1916         kdb_printf("ERROR: Register set currently not implemented\n");
1917     return 0;
1918 #endif
1919 }
1920
1921 #if defined(CONFIG_MAGIC_SYSRQ)
1922 /*
1923  * kdb_sr - This function implements the 'sr' (SYSRQ key) command
1924  *      which interfaces to the soi-disant MAGIC SYSRQ functionality.
1925  *              sr <magic-sysrq-code>
1926  */
1927 static int kdb_sr(int argc, const char **argv)
1928 {
1929         if (argc != 1)
1930                 return KDB_ARGCOUNT;
1931         kdb_trap_printk++;
1932         __handle_sysrq(*argv[1], false);
1933         kdb_trap_printk--;
1934
1935         return 0;
1936 }
1937 #endif  /* CONFIG_MAGIC_SYSRQ */
1938
1939 /*
1940  * kdb_ef - This function implements the 'regs' (display exception
1941  *      frame) command.  This command takes an address and expects to
1942  *      find an exception frame at that address, formats and prints
1943  *      it.
1944  *              regs address-expression
1945  * Remarks:
1946  *      Not done yet.
1947  */
1948 static int kdb_ef(int argc, const char **argv)
1949 {
1950         int diag;
1951         unsigned long addr;
1952         long offset;
1953         int nextarg;
1954
1955         if (argc != 1)
1956                 return KDB_ARGCOUNT;
1957
1958         nextarg = 1;
1959         diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
1960         if (diag)
1961                 return diag;
1962         show_regs((struct pt_regs *)addr);
1963         return 0;
1964 }
1965
1966 #if defined(CONFIG_MODULES)
1967 /*
1968  * kdb_lsmod - This function implements the 'lsmod' command.  Lists
1969  *      currently loaded kernel modules.
1970  *      Mostly taken from userland lsmod.
1971  */
1972 static int kdb_lsmod(int argc, const char **argv)
1973 {
1974         struct module *mod;
1975
1976         if (argc != 0)
1977                 return KDB_ARGCOUNT;
1978
1979         kdb_printf("Module                  Size  modstruct     Used by\n");
1980         list_for_each_entry(mod, kdb_modules, list) {
1981
1982                 kdb_printf("%-20s%8u  0x%p ", mod->name,
1983                            mod->core_size, (void *)mod);
1984 #ifdef CONFIG_MODULE_UNLOAD
1985                 kdb_printf("%4d ", module_refcount(mod));
1986 #endif
1987                 if (mod->state == MODULE_STATE_GOING)
1988                         kdb_printf(" (Unloading)");
1989                 else if (mod->state == MODULE_STATE_COMING)
1990                         kdb_printf(" (Loading)");
1991                 else
1992                         kdb_printf(" (Live)");
1993                 kdb_printf(" 0x%p", mod->module_core);
1994
1995 #ifdef CONFIG_MODULE_UNLOAD
1996                 {
1997                         struct module_use *use;
1998                         kdb_printf(" [ ");
1999                         list_for_each_entry(use, &mod->source_list,
2000                                             source_list)
2001                                 kdb_printf("%s ", use->target->name);
2002                         kdb_printf("]\n");
2003                 }
2004 #endif
2005         }
2006
2007         return 0;
2008 }
2009
2010 #endif  /* CONFIG_MODULES */
2011
2012 /*
2013  * kdb_env - This function implements the 'env' command.  Display the
2014  *      current environment variables.
2015  */
2016
2017 static int kdb_env(int argc, const char **argv)
2018 {
2019         int i;
2020
2021         for (i = 0; i < __nenv; i++) {
2022                 if (__env[i])
2023                         kdb_printf("%s\n", __env[i]);
2024         }
2025
2026         if (KDB_DEBUG(MASK))
2027                 kdb_printf("KDBFLAGS=0x%x\n", kdb_flags);
2028
2029         return 0;
2030 }
2031
2032 #ifdef CONFIG_PRINTK
2033 /*
2034  * kdb_dmesg - This function implements the 'dmesg' command to display
2035  *      the contents of the syslog buffer.
2036  *              dmesg [lines] [adjust]
2037  */
2038 static int kdb_dmesg(int argc, const char **argv)
2039 {
2040         char *syslog_data[4], *start, *end, c = '\0', *p;
2041         int diag, logging, logsize, lines = 0, adjust = 0, n;
2042
2043         if (argc > 2)
2044                 return KDB_ARGCOUNT;
2045         if (argc) {
2046                 char *cp;
2047                 lines = simple_strtol(argv[1], &cp, 0);
2048                 if (*cp)
2049                         lines = 0;
2050                 if (argc > 1) {
2051                         adjust = simple_strtoul(argv[2], &cp, 0);
2052                         if (*cp || adjust < 0)
2053                                 adjust = 0;
2054                 }
2055         }
2056
2057         /* disable LOGGING if set */
2058         diag = kdbgetintenv("LOGGING", &logging);
2059         if (!diag && logging) {
2060                 const char *setargs[] = { "set", "LOGGING", "0" };
2061                 kdb_set(2, setargs);
2062         }
2063
2064         /* syslog_data[0,1] physical start, end+1.  syslog_data[2,3]
2065          * logical start, end+1. */
2066         kdb_syslog_data(syslog_data);
2067         if (syslog_data[2] == syslog_data[3])
2068                 return 0;
2069         logsize = syslog_data[1] - syslog_data[0];
2070         start = syslog_data[2];
2071         end = syslog_data[3];
2072 #define KDB_WRAP(p) (((p - syslog_data[0]) % logsize) + syslog_data[0])
2073         for (n = 0, p = start; p < end; ++p) {
2074                 c = *KDB_WRAP(p);
2075                 if (c == '\n')
2076                         ++n;
2077         }
2078         if (c != '\n')
2079                 ++n;
2080         if (lines < 0) {
2081                 if (adjust >= n)
2082                         kdb_printf("buffer only contains %d lines, nothing "
2083                                    "printed\n", n);
2084                 else if (adjust - lines >= n)
2085                         kdb_printf("buffer only contains %d lines, last %d "
2086                                    "lines printed\n", n, n - adjust);
2087                 if (adjust) {
2088                         for (; start < end && adjust; ++start) {
2089                                 if (*KDB_WRAP(start) == '\n')
2090                                         --adjust;
2091                         }
2092                         if (start < end)
2093                                 ++start;
2094                 }
2095                 for (p = start; p < end && lines; ++p) {
2096                         if (*KDB_WRAP(p) == '\n')
2097                                 ++lines;
2098                 }
2099                 end = p;
2100         } else if (lines > 0) {
2101                 int skip = n - (adjust + lines);
2102                 if (adjust >= n) {
2103                         kdb_printf("buffer only contains %d lines, "
2104                                    "nothing printed\n", n);
2105                         skip = n;
2106                 } else if (skip < 0) {
2107                         lines += skip;
2108                         skip = 0;
2109                         kdb_printf("buffer only contains %d lines, first "
2110                                    "%d lines printed\n", n, lines);
2111                 }
2112                 for (; start < end && skip; ++start) {
2113                         if (*KDB_WRAP(start) == '\n')
2114                                 --skip;
2115                 }
2116                 for (p = start; p < end && lines; ++p) {
2117                         if (*KDB_WRAP(p) == '\n')
2118                                 --lines;
2119                 }
2120                 end = p;
2121         }
2122         /* Do a line at a time (max 200 chars) to reduce protocol overhead */
2123         c = '\n';
2124         while (start != end) {
2125                 char buf[201];
2126                 p = buf;
2127                 if (KDB_FLAG(CMD_INTERRUPT))
2128                         return 0;
2129                 while (start < end && (c = *KDB_WRAP(start)) &&
2130                        (p - buf) < sizeof(buf)-1) {
2131                         ++start;
2132                         *p++ = c;
2133                         if (c == '\n')
2134                                 break;
2135                 }
2136                 *p = '\0';
2137                 kdb_printf("%s", buf);
2138         }
2139         if (c != '\n')
2140                 kdb_printf("\n");
2141
2142         return 0;
2143 }
2144 #endif /* CONFIG_PRINTK */
2145 /*
2146  * kdb_cpu - This function implements the 'cpu' command.
2147  *      cpu     [<cpunum>]
2148  * Returns:
2149  *      KDB_CMD_CPU for success, a kdb diagnostic if error
2150  */
2151 static void kdb_cpu_status(void)
2152 {
2153         int i, start_cpu, first_print = 1;
2154         char state, prev_state = '?';
2155
2156         kdb_printf("Currently on cpu %d\n", raw_smp_processor_id());
2157         kdb_printf("Available cpus: ");
2158         for (start_cpu = -1, i = 0; i < NR_CPUS; i++) {
2159                 if (!cpu_online(i)) {
2160                         state = 'F';    /* cpu is offline */
2161                 } else {
2162                         state = ' ';    /* cpu is responding to kdb */
2163                         if (kdb_task_state_char(KDB_TSK(i)) == 'I')
2164                                 state = 'I';    /* idle task */
2165                 }
2166                 if (state != prev_state) {
2167                         if (prev_state != '?') {
2168                                 if (!first_print)
2169                                         kdb_printf(", ");
2170                                 first_print = 0;
2171                                 kdb_printf("%d", start_cpu);
2172                                 if (start_cpu < i-1)
2173                                         kdb_printf("-%d", i-1);
2174                                 if (prev_state != ' ')
2175                                         kdb_printf("(%c)", prev_state);
2176                         }
2177                         prev_state = state;
2178                         start_cpu = i;
2179                 }
2180         }
2181         /* print the trailing cpus, ignoring them if they are all offline */
2182         if (prev_state != 'F') {
2183                 if (!first_print)
2184                         kdb_printf(", ");
2185                 kdb_printf("%d", start_cpu);
2186                 if (start_cpu < i-1)
2187                         kdb_printf("-%d", i-1);
2188                 if (prev_state != ' ')
2189                         kdb_printf("(%c)", prev_state);
2190         }
2191         kdb_printf("\n");
2192 }
2193
2194 static int kdb_cpu(int argc, const char **argv)
2195 {
2196         unsigned long cpunum;
2197         int diag;
2198
2199         if (argc == 0) {
2200                 kdb_cpu_status();
2201                 return 0;
2202         }
2203
2204         if (argc != 1)
2205                 return KDB_ARGCOUNT;
2206
2207         diag = kdbgetularg(argv[1], &cpunum);
2208         if (diag)
2209                 return diag;
2210
2211         /*
2212          * Validate cpunum
2213          */
2214         if ((cpunum > NR_CPUS) || !cpu_online(cpunum))
2215                 return KDB_BADCPUNUM;
2216
2217         dbg_switch_cpu = cpunum;
2218
2219         /*
2220          * Switch to other cpu
2221          */
2222         return KDB_CMD_CPU;
2223 }
2224
2225 /* The user may not realize that ps/bta with no parameters does not print idle
2226  * or sleeping system daemon processes, so tell them how many were suppressed.
2227  */
2228 void kdb_ps_suppressed(void)
2229 {
2230         int idle = 0, daemon = 0;
2231         unsigned long mask_I = kdb_task_state_string("I"),
2232                       mask_M = kdb_task_state_string("M");
2233         unsigned long cpu;
2234         const struct task_struct *p, *g;
2235         for_each_online_cpu(cpu) {
2236                 p = kdb_curr_task(cpu);
2237                 if (kdb_task_state(p, mask_I))
2238                         ++idle;
2239         }
2240         kdb_do_each_thread(g, p) {
2241                 if (kdb_task_state(p, mask_M))
2242                         ++daemon;
2243         } kdb_while_each_thread(g, p);
2244         if (idle || daemon) {
2245                 if (idle)
2246                         kdb_printf("%d idle process%s (state I)%s\n",
2247                                    idle, idle == 1 ? "" : "es",
2248                                    daemon ? " and " : "");
2249                 if (daemon)
2250                         kdb_printf("%d sleeping system daemon (state M) "
2251                                    "process%s", daemon,
2252                                    daemon == 1 ? "" : "es");
2253                 kdb_printf(" suppressed,\nuse 'ps A' to see all.\n");
2254         }
2255 }
2256
2257 /*
2258  * kdb_ps - This function implements the 'ps' command which shows a
2259  *      list of the active processes.
2260  *              ps [DRSTCZEUIMA]   All processes, optionally filtered by state
2261  */
2262 void kdb_ps1(const struct task_struct *p)
2263 {
2264         int cpu;
2265         unsigned long tmp;
2266
2267         if (!p || probe_kernel_read(&tmp, (char *)p, sizeof(unsigned long)))
2268                 return;
2269
2270         cpu = kdb_process_cpu(p);
2271         kdb_printf("0x%p %8d %8d  %d %4d   %c  0x%p %c%s\n",
2272                    (void *)p, p->pid, p->parent->pid,
2273                    kdb_task_has_cpu(p), kdb_process_cpu(p),
2274                    kdb_task_state_char(p),
2275                    (void *)(&p->thread),
2276                    p == kdb_curr_task(raw_smp_processor_id()) ? '*' : ' ',
2277                    p->comm);
2278         if (kdb_task_has_cpu(p)) {
2279                 if (!KDB_TSK(cpu)) {
2280                         kdb_printf("  Error: no saved data for this cpu\n");
2281                 } else {
2282                         if (KDB_TSK(cpu) != p)
2283                                 kdb_printf("  Error: does not match running "
2284                                    "process table (0x%p)\n", KDB_TSK(cpu));
2285                 }
2286         }
2287 }
2288
2289 static int kdb_ps(int argc, const char **argv)
2290 {
2291         struct task_struct *g, *p;
2292         unsigned long mask, cpu;
2293
2294         if (argc == 0)
2295                 kdb_ps_suppressed();
2296         kdb_printf("%-*s      Pid   Parent [*] cpu State %-*s Command\n",
2297                 (int)(2*sizeof(void *))+2, "Task Addr",
2298                 (int)(2*sizeof(void *))+2, "Thread");
2299         mask = kdb_task_state_string(argc ? argv[1] : NULL);
2300         /* Run the active tasks first */
2301         for_each_online_cpu(cpu) {
2302                 if (KDB_FLAG(CMD_INTERRUPT))
2303                         return 0;
2304                 p = kdb_curr_task(cpu);
2305                 if (kdb_task_state(p, mask))
2306                         kdb_ps1(p);
2307         }
2308         kdb_printf("\n");
2309         /* Now the real tasks */
2310         kdb_do_each_thread(g, p) {
2311                 if (KDB_FLAG(CMD_INTERRUPT))
2312                         return 0;
2313                 if (kdb_task_state(p, mask))
2314                         kdb_ps1(p);
2315         } kdb_while_each_thread(g, p);
2316
2317         return 0;
2318 }
2319
2320 /*
2321  * kdb_pid - This function implements the 'pid' command which switches
2322  *      the currently active process.
2323  *              pid [<pid> | R]
2324  */
2325 static int kdb_pid(int argc, const char **argv)
2326 {
2327         struct task_struct *p;
2328         unsigned long val;
2329         int diag;
2330
2331         if (argc > 1)
2332                 return KDB_ARGCOUNT;
2333
2334         if (argc) {
2335                 if (strcmp(argv[1], "R") == 0) {
2336                         p = KDB_TSK(kdb_initial_cpu);
2337                 } else {
2338                         diag = kdbgetularg(argv[1], &val);
2339                         if (diag)
2340                                 return KDB_BADINT;
2341
2342                         p = find_task_by_pid_ns((pid_t)val,     &init_pid_ns);
2343                         if (!p) {
2344                                 kdb_printf("No task with pid=%d\n", (pid_t)val);
2345                                 return 0;
2346                         }
2347                 }
2348                 kdb_set_current_task(p);
2349         }
2350         kdb_printf("KDB current process is %s(pid=%d)\n",
2351                    kdb_current_task->comm,
2352                    kdb_current_task->pid);
2353
2354         return 0;
2355 }
2356
2357 /*
2358  * kdb_ll - This function implements the 'll' command which follows a
2359  *      linked list and executes an arbitrary command for each
2360  *      element.
2361  */
2362 static int kdb_ll(int argc, const char **argv)
2363 {
2364         int diag;
2365         unsigned long addr;
2366         long offset = 0;
2367         unsigned long va;
2368         unsigned long linkoffset;
2369         int nextarg;
2370         const char *command;
2371
2372         if (argc != 3)
2373                 return KDB_ARGCOUNT;
2374
2375         nextarg = 1;
2376         diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
2377         if (diag)
2378                 return diag;
2379
2380         diag = kdbgetularg(argv[2], &linkoffset);
2381         if (diag)
2382                 return diag;
2383
2384         /*
2385          * Using the starting address as
2386          * the first element in the list, and assuming that
2387          * the list ends with a null pointer.
2388          */
2389
2390         va = addr;
2391         command = kdb_strdup(argv[3], GFP_KDB);
2392         if (!command) {
2393                 kdb_printf("%s: cannot duplicate command\n", __func__);
2394                 return 0;
2395         }
2396         /* Recursive use of kdb_parse, do not use argv after this point */
2397         argv = NULL;
2398
2399         while (va) {
2400                 char buf[80];
2401
2402                 if (KDB_FLAG(CMD_INTERRUPT))
2403                         return 0;
2404
2405                 sprintf(buf, "%s " kdb_machreg_fmt "\n", command, va);
2406                 diag = kdb_parse(buf);
2407                 if (diag)
2408                         return diag;
2409
2410                 addr = va + linkoffset;
2411                 if (kdb_getword(&va, addr, sizeof(va)))
2412                         return 0;
2413         }
2414         kfree(command);
2415
2416         return 0;
2417 }
2418
2419 static int kdb_kgdb(int argc, const char **argv)
2420 {
2421         return KDB_CMD_KGDB;
2422 }
2423
2424 /*
2425  * kdb_help - This function implements the 'help' and '?' commands.
2426  */
2427 static int kdb_help(int argc, const char **argv)
2428 {
2429         kdbtab_t *kt;
2430         int i;
2431
2432         kdb_printf("%-15.15s %-20.20s %s\n", "Command", "Usage", "Description");
2433         kdb_printf("-----------------------------"
2434                    "-----------------------------\n");
2435         for_each_kdbcmd(kt, i) {
2436                 if (kt->cmd_name)
2437                         kdb_printf("%-15.15s %-20.20s %s\n", kt->cmd_name,
2438                                    kt->cmd_usage, kt->cmd_help);
2439                 if (KDB_FLAG(CMD_INTERRUPT))
2440                         return 0;
2441         }
2442         return 0;
2443 }
2444
2445 /*
2446  * kdb_kill - This function implements the 'kill' commands.
2447  */
2448 static int kdb_kill(int argc, const char **argv)
2449 {
2450         long sig, pid;
2451         char *endp;
2452         struct task_struct *p;
2453         struct siginfo info;
2454
2455         if (argc != 2)
2456                 return KDB_ARGCOUNT;
2457
2458         sig = simple_strtol(argv[1], &endp, 0);
2459         if (*endp)
2460                 return KDB_BADINT;
2461         if (sig >= 0) {
2462                 kdb_printf("Invalid signal parameter.<-signal>\n");
2463                 return 0;
2464         }
2465         sig = -sig;
2466
2467         pid = simple_strtol(argv[2], &endp, 0);
2468         if (*endp)
2469                 return KDB_BADINT;
2470         if (pid <= 0) {
2471                 kdb_printf("Process ID must be large than 0.\n");
2472                 return 0;
2473         }
2474
2475         /* Find the process. */
2476         p = find_task_by_pid_ns(pid, &init_pid_ns);
2477         if (!p) {
2478                 kdb_printf("The specified process isn't found.\n");
2479                 return 0;
2480         }
2481         p = p->group_leader;
2482         info.si_signo = sig;
2483         info.si_errno = 0;
2484         info.si_code = SI_USER;
2485         info.si_pid = pid;  /* same capabilities as process being signalled */
2486         info.si_uid = 0;    /* kdb has root authority */
2487         kdb_send_sig_info(p, &info);
2488         return 0;
2489 }
2490
2491 struct kdb_tm {
2492         int tm_sec;     /* seconds */
2493         int tm_min;     /* minutes */
2494         int tm_hour;    /* hours */
2495         int tm_mday;    /* day of the month */
2496         int tm_mon;     /* month */
2497         int tm_year;    /* year */
2498 };
2499
2500 static void kdb_gmtime(struct timespec *tv, struct kdb_tm *tm)
2501 {
2502         /* This will work from 1970-2099, 2100 is not a leap year */
2503         static int mon_day[] = { 31, 29, 31, 30, 31, 30, 31,
2504                                  31, 30, 31, 30, 31 };
2505         memset(tm, 0, sizeof(*tm));
2506         tm->tm_sec  = tv->tv_sec % (24 * 60 * 60);
2507         tm->tm_mday = tv->tv_sec / (24 * 60 * 60) +
2508                 (2 * 365 + 1); /* shift base from 1970 to 1968 */
2509         tm->tm_min =  tm->tm_sec / 60 % 60;
2510         tm->tm_hour = tm->tm_sec / 60 / 60;
2511         tm->tm_sec =  tm->tm_sec % 60;
2512         tm->tm_year = 68 + 4*(tm->tm_mday / (4*365+1));
2513         tm->tm_mday %= (4*365+1);
2514         mon_day[1] = 29;
2515         while (tm->tm_mday >= mon_day[tm->tm_mon]) {
2516                 tm->tm_mday -= mon_day[tm->tm_mon];
2517                 if (++tm->tm_mon == 12) {
2518                         tm->tm_mon = 0;
2519                         ++tm->tm_year;
2520                         mon_day[1] = 28;
2521                 }
2522         }
2523         ++tm->tm_mday;
2524 }
2525
2526 /*
2527  * Most of this code has been lifted from kernel/timer.c::sys_sysinfo().
2528  * I cannot call that code directly from kdb, it has an unconditional
2529  * cli()/sti() and calls routines that take locks which can stop the debugger.
2530  */
2531 static void kdb_sysinfo(struct sysinfo *val)
2532 {
2533         struct timespec uptime;
2534         do_posix_clock_monotonic_gettime(&uptime);
2535         memset(val, 0, sizeof(*val));
2536         val->uptime = uptime.tv_sec;
2537         val->loads[0] = avenrun[0];
2538         val->loads[1] = avenrun[1];
2539         val->loads[2] = avenrun[2];
2540         val->procs = nr_threads-1;
2541         si_meminfo(val);
2542
2543         return;
2544 }
2545
2546 /*
2547  * kdb_summary - This function implements the 'summary' command.
2548  */
2549 static int kdb_summary(int argc, const char **argv)
2550 {
2551         struct timespec now;
2552         struct kdb_tm tm;
2553         struct sysinfo val;
2554
2555         if (argc)
2556                 return KDB_ARGCOUNT;
2557
2558         kdb_printf("sysname    %s\n", init_uts_ns.name.sysname);
2559         kdb_printf("release    %s\n", init_uts_ns.name.release);
2560         kdb_printf("version    %s\n", init_uts_ns.name.version);
2561         kdb_printf("machine    %s\n", init_uts_ns.name.machine);
2562         kdb_printf("nodename   %s\n", init_uts_ns.name.nodename);
2563         kdb_printf("domainname %s\n", init_uts_ns.name.domainname);
2564         kdb_printf("ccversion  %s\n", __stringify(CCVERSION));
2565
2566         now = __current_kernel_time();
2567         kdb_gmtime(&now, &tm);
2568         kdb_printf("date       %04d-%02d-%02d %02d:%02d:%02d "
2569                    "tz_minuteswest %d\n",
2570                 1900+tm.tm_year, tm.tm_mon+1, tm.tm_mday,
2571                 tm.tm_hour, tm.tm_min, tm.tm_sec,
2572                 sys_tz.tz_minuteswest);
2573
2574         kdb_sysinfo(&val);
2575         kdb_printf("uptime     ");
2576         if (val.uptime > (24*60*60)) {
2577                 int days = val.uptime / (24*60*60);
2578                 val.uptime %= (24*60*60);
2579                 kdb_printf("%d day%s ", days, days == 1 ? "" : "s");
2580         }
2581         kdb_printf("%02ld:%02ld\n", val.uptime/(60*60), (val.uptime/60)%60);
2582
2583         /* lifted from fs/proc/proc_misc.c::loadavg_read_proc() */
2584
2585 #define LOAD_INT(x) ((x) >> FSHIFT)
2586 #define LOAD_FRAC(x) LOAD_INT(((x) & (FIXED_1-1)) * 100)
2587         kdb_printf("load avg   %ld.%02ld %ld.%02ld %ld.%02ld\n",
2588                 LOAD_INT(val.loads[0]), LOAD_FRAC(val.loads[0]),
2589                 LOAD_INT(val.loads[1]), LOAD_FRAC(val.loads[1]),
2590                 LOAD_INT(val.loads[2]), LOAD_FRAC(val.loads[2]));
2591 #undef LOAD_INT
2592 #undef LOAD_FRAC
2593         /* Display in kilobytes */
2594 #define K(x) ((x) << (PAGE_SHIFT - 10))
2595         kdb_printf("\nMemTotal:       %8lu kB\nMemFree:        %8lu kB\n"
2596                    "Buffers:        %8lu kB\n",
2597                    val.totalram, val.freeram, val.bufferram);
2598         return 0;
2599 }
2600
2601 /*
2602  * kdb_per_cpu - This function implements the 'per_cpu' command.
2603  */
2604 static int kdb_per_cpu(int argc, const char **argv)
2605 {
2606         char buf[256], fmtstr[64];
2607         kdb_symtab_t symtab;
2608         cpumask_t suppress = CPU_MASK_NONE;
2609         int cpu, diag;
2610         unsigned long addr, val, bytesperword = 0, whichcpu = ~0UL;
2611
2612         if (argc < 1 || argc > 3)
2613                 return KDB_ARGCOUNT;
2614
2615         snprintf(buf, sizeof(buf), "per_cpu__%s", argv[1]);
2616         if (!kdbgetsymval(buf, &symtab)) {
2617                 kdb_printf("%s is not a per_cpu variable\n", argv[1]);
2618                 return KDB_BADADDR;
2619         }
2620         if (argc >= 2) {
2621                 diag = kdbgetularg(argv[2], &bytesperword);
2622                 if (diag)
2623                         return diag;
2624         }
2625         if (!bytesperword)
2626                 bytesperword = KDB_WORD_SIZE;
2627         else if (bytesperword > KDB_WORD_SIZE)
2628                 return KDB_BADWIDTH;
2629         sprintf(fmtstr, "%%0%dlx ", (int)(2*bytesperword));
2630         if (argc >= 3) {
2631                 diag = kdbgetularg(argv[3], &whichcpu);
2632                 if (diag)
2633                         return diag;
2634                 if (!cpu_online(whichcpu)) {
2635                         kdb_printf("cpu %ld is not online\n", whichcpu);
2636                         return KDB_BADCPUNUM;
2637                 }
2638         }
2639
2640         /* Most architectures use __per_cpu_offset[cpu], some use
2641          * __per_cpu_offset(cpu), smp has no __per_cpu_offset.
2642          */
2643 #ifdef  __per_cpu_offset
2644 #define KDB_PCU(cpu) __per_cpu_offset(cpu)
2645 #else
2646 #ifdef  CONFIG_SMP
2647 #define KDB_PCU(cpu) __per_cpu_offset[cpu]
2648 #else
2649 #define KDB_PCU(cpu) 0
2650 #endif
2651 #endif
2652
2653         for_each_online_cpu(cpu) {
2654                 if (whichcpu != ~0UL && whichcpu != cpu)
2655                         continue;
2656                 addr = symtab.sym_start + KDB_PCU(cpu);
2657                 diag = kdb_getword(&val, addr, bytesperword);
2658                 if (diag) {
2659                         kdb_printf("%5d " kdb_bfd_vma_fmt0 " - unable to "
2660                                    "read, diag=%d\n", cpu, addr, diag);
2661                         continue;
2662                 }
2663 #ifdef  CONFIG_SMP
2664                 if (!val) {
2665                         cpu_set(cpu, suppress);
2666                         continue;
2667                 }
2668 #endif  /* CONFIG_SMP */
2669                 kdb_printf("%5d ", cpu);
2670                 kdb_md_line(fmtstr, addr,
2671                         bytesperword == KDB_WORD_SIZE,
2672                         1, bytesperword, 1, 1, 0);
2673         }
2674         if (cpus_weight(suppress) == 0)
2675                 return 0;
2676         kdb_printf("Zero suppressed cpu(s):");
2677         for (cpu = first_cpu(suppress); cpu < num_possible_cpus();
2678              cpu = next_cpu(cpu, suppress)) {
2679                 kdb_printf(" %d", cpu);
2680                 if (cpu == num_possible_cpus() - 1 ||
2681                     next_cpu(cpu, suppress) != cpu + 1)
2682                         continue;
2683                 while (cpu < num_possible_cpus() &&
2684                        next_cpu(cpu, suppress) == cpu + 1)
2685                         ++cpu;
2686                 kdb_printf("-%d", cpu);
2687         }
2688         kdb_printf("\n");
2689
2690 #undef KDB_PCU
2691
2692         return 0;
2693 }
2694
2695 /*
2696  * display help for the use of cmd | grep pattern
2697  */
2698 static int kdb_grep_help(int argc, const char **argv)
2699 {
2700         kdb_printf("Usage of  cmd args | grep pattern:\n");
2701         kdb_printf("  Any command's output may be filtered through an ");
2702         kdb_printf("emulated 'pipe'.\n");
2703         kdb_printf("  'grep' is just a key word.\n");
2704         kdb_printf("  The pattern may include a very limited set of "
2705                    "metacharacters:\n");
2706         kdb_printf("   pattern or ^pattern or pattern$ or ^pattern$\n");
2707         kdb_printf("  And if there are spaces in the pattern, you may "
2708                    "quote it:\n");
2709         kdb_printf("   \"pat tern\" or \"^pat tern\" or \"pat tern$\""
2710                    " or \"^pat tern$\"\n");
2711         return 0;
2712 }
2713
2714 /*
2715  * kdb_register_repeat - This function is used to register a kernel
2716  *      debugger command.
2717  * Inputs:
2718  *      cmd     Command name
2719  *      func    Function to execute the command
2720  *      usage   A simple usage string showing arguments
2721  *      help    A simple help string describing command
2722  *      repeat  Does the command auto repeat on enter?
2723  * Returns:
2724  *      zero for success, one if a duplicate command.
2725  */
2726 #define kdb_command_extend 50   /* arbitrary */
2727 int kdb_register_repeat(char *cmd,
2728                         kdb_func_t func,
2729                         char *usage,
2730                         char *help,
2731                         short minlen,
2732                         kdb_repeat_t repeat)
2733 {
2734         int i;
2735         kdbtab_t *kp;
2736
2737         /*
2738          *  Brute force method to determine duplicates
2739          */
2740         for_each_kdbcmd(kp, i) {
2741                 if (kp->cmd_name && (strcmp(kp->cmd_name, cmd) == 0)) {
2742                         kdb_printf("Duplicate kdb command registered: "
2743                                 "%s, func %p help %s\n", cmd, func, help);
2744                         return 1;
2745                 }
2746         }
2747
2748         /*
2749          * Insert command into first available location in table
2750          */
2751         for_each_kdbcmd(kp, i) {
2752                 if (kp->cmd_name == NULL)
2753                         break;
2754         }
2755
2756         if (i >= kdb_max_commands) {
2757                 kdbtab_t *new = kmalloc((kdb_max_commands - KDB_BASE_CMD_MAX +
2758                          kdb_command_extend) * sizeof(*new), GFP_KDB);
2759                 if (!new) {
2760                         kdb_printf("Could not allocate new kdb_command "
2761                                    "table\n");
2762                         return 1;
2763                 }
2764                 if (kdb_commands) {
2765                         memcpy(new, kdb_commands,
2766                                kdb_max_commands * sizeof(*new));
2767                         kfree(kdb_commands);
2768                 }
2769                 memset(new + kdb_max_commands, 0,
2770                        kdb_command_extend * sizeof(*new));
2771                 kdb_commands = new;
2772                 kp = kdb_commands + kdb_max_commands;
2773                 kdb_max_commands += kdb_command_extend;
2774         }
2775
2776         kp->cmd_name   = cmd;
2777         kp->cmd_func   = func;
2778         kp->cmd_usage  = usage;
2779         kp->cmd_help   = help;
2780         kp->cmd_flags  = 0;
2781         kp->cmd_minlen = minlen;
2782         kp->cmd_repeat = repeat;
2783
2784         return 0;
2785 }
2786 EXPORT_SYMBOL_GPL(kdb_register_repeat);
2787
2788
2789 /*
2790  * kdb_register - Compatibility register function for commands that do
2791  *      not need to specify a repeat state.  Equivalent to
2792  *      kdb_register_repeat with KDB_REPEAT_NONE.
2793  * Inputs:
2794  *      cmd     Command name
2795  *      func    Function to execute the command
2796  *      usage   A simple usage string showing arguments
2797  *      help    A simple help string describing command
2798  * Returns:
2799  *      zero for success, one if a duplicate command.
2800  */
2801 int kdb_register(char *cmd,
2802              kdb_func_t func,
2803              char *usage,
2804              char *help,
2805              short minlen)
2806 {
2807         return kdb_register_repeat(cmd, func, usage, help, minlen,
2808                                    KDB_REPEAT_NONE);
2809 }
2810 EXPORT_SYMBOL_GPL(kdb_register);
2811
2812 /*
2813  * kdb_unregister - This function is used to unregister a kernel
2814  *      debugger command.  It is generally called when a module which
2815  *      implements kdb commands is unloaded.
2816  * Inputs:
2817  *      cmd     Command name
2818  * Returns:
2819  *      zero for success, one command not registered.
2820  */
2821 int kdb_unregister(char *cmd)
2822 {
2823         int i;
2824         kdbtab_t *kp;
2825
2826         /*
2827          *  find the command.
2828          */
2829         for (i = 0, kp = kdb_commands; i < kdb_max_commands; i++, kp++) {
2830                 if (kp->cmd_name && (strcmp(kp->cmd_name, cmd) == 0)) {
2831                         kp->cmd_name = NULL;
2832                         return 0;
2833                 }
2834         }
2835
2836         /* Couldn't find it.  */
2837         return 1;
2838 }
2839 EXPORT_SYMBOL_GPL(kdb_unregister);
2840
2841 /* Initialize the kdb command table. */
2842 static void __init kdb_inittab(void)
2843 {
2844         int i;
2845         kdbtab_t *kp;
2846
2847         for_each_kdbcmd(kp, i)
2848                 kp->cmd_name = NULL;
2849
2850         kdb_register_repeat("md", kdb_md, "<vaddr>",
2851           "Display Memory Contents, also mdWcN, e.g. md8c1", 1,
2852                             KDB_REPEAT_NO_ARGS);
2853         kdb_register_repeat("mdr", kdb_md, "<vaddr> <bytes>",
2854           "Display Raw Memory", 0, KDB_REPEAT_NO_ARGS);
2855         kdb_register_repeat("mdp", kdb_md, "<paddr> <bytes>",
2856           "Display Physical Memory", 0, KDB_REPEAT_NO_ARGS);
2857         kdb_register_repeat("mds", kdb_md, "<vaddr>",
2858           "Display Memory Symbolically", 0, KDB_REPEAT_NO_ARGS);
2859         kdb_register_repeat("mm", kdb_mm, "<vaddr> <contents>",
2860           "Modify Memory Contents", 0, KDB_REPEAT_NO_ARGS);
2861         kdb_register_repeat("go", kdb_go, "[<vaddr>]",
2862           "Continue Execution", 1, KDB_REPEAT_NONE);
2863         kdb_register_repeat("rd", kdb_rd, "",
2864           "Display Registers", 0, KDB_REPEAT_NONE);
2865         kdb_register_repeat("rm", kdb_rm, "<reg> <contents>",
2866           "Modify Registers", 0, KDB_REPEAT_NONE);
2867         kdb_register_repeat("ef", kdb_ef, "<vaddr>",
2868           "Display exception frame", 0, KDB_REPEAT_NONE);
2869         kdb_register_repeat("bt", kdb_bt, "[<vaddr>]",
2870           "Stack traceback", 1, KDB_REPEAT_NONE);
2871         kdb_register_repeat("btp", kdb_bt, "<pid>",
2872           "Display stack for process <pid>", 0, KDB_REPEAT_NONE);
2873         kdb_register_repeat("bta", kdb_bt, "[DRSTCZEUIMA]",
2874           "Display stack all processes", 0, KDB_REPEAT_NONE);
2875         kdb_register_repeat("btc", kdb_bt, "",
2876           "Backtrace current process on each cpu", 0, KDB_REPEAT_NONE);
2877         kdb_register_repeat("btt", kdb_bt, "<vaddr>",
2878           "Backtrace process given its struct task address", 0,
2879                             KDB_REPEAT_NONE);
2880         kdb_register_repeat("ll", kdb_ll, "<first-element> <linkoffset> <cmd>",
2881           "Execute cmd for each element in linked list", 0, KDB_REPEAT_NONE);
2882         kdb_register_repeat("env", kdb_env, "",
2883           "Show environment variables", 0, KDB_REPEAT_NONE);
2884         kdb_register_repeat("set", kdb_set, "",
2885           "Set environment variables", 0, KDB_REPEAT_NONE);
2886         kdb_register_repeat("help", kdb_help, "",
2887           "Display Help Message", 1, KDB_REPEAT_NONE);
2888         kdb_register_repeat("?", kdb_help, "",
2889           "Display Help Message", 0, KDB_REPEAT_NONE);
2890         kdb_register_repeat("cpu", kdb_cpu, "<cpunum>",
2891           "Switch to new cpu", 0, KDB_REPEAT_NONE);
2892         kdb_register_repeat("kgdb", kdb_kgdb, "",
2893           "Enter kgdb mode", 0, KDB_REPEAT_NONE);
2894         kdb_register_repeat("ps", kdb_ps, "[<flags>|A]",
2895           "Display active task list", 0, KDB_REPEAT_NONE);
2896         kdb_register_repeat("pid", kdb_pid, "<pidnum>",
2897           "Switch to another task", 0, KDB_REPEAT_NONE);
2898         kdb_register_repeat("reboot", kdb_reboot, "",
2899           "Reboot the machine immediately", 0, KDB_REPEAT_NONE);
2900 #if defined(CONFIG_MODULES)
2901         kdb_register_repeat("lsmod", kdb_lsmod, "",
2902           "List loaded kernel modules", 0, KDB_REPEAT_NONE);
2903 #endif
2904 #if defined(CONFIG_MAGIC_SYSRQ)
2905         kdb_register_repeat("sr", kdb_sr, "<key>",
2906           "Magic SysRq key", 0, KDB_REPEAT_NONE);
2907 #endif
2908 #if defined(CONFIG_PRINTK)
2909         kdb_register_repeat("dmesg", kdb_dmesg, "[lines]",
2910           "Display syslog buffer", 0, KDB_REPEAT_NONE);
2911 #endif
2912         kdb_register_repeat("defcmd", kdb_defcmd, "name \"usage\" \"help\"",
2913           "Define a set of commands, down to endefcmd", 0, KDB_REPEAT_NONE);
2914         kdb_register_repeat("kill", kdb_kill, "<-signal> <pid>",
2915           "Send a signal to a process", 0, KDB_REPEAT_NONE);
2916         kdb_register_repeat("summary", kdb_summary, "",
2917           "Summarize the system", 4, KDB_REPEAT_NONE);
2918         kdb_register_repeat("per_cpu", kdb_per_cpu, "",
2919           "Display per_cpu variables", 3, KDB_REPEAT_NONE);
2920         kdb_register_repeat("grephelp", kdb_grep_help, "",
2921           "Display help on | grep", 0, KDB_REPEAT_NONE);
2922 }
2923
2924 /* Execute any commands defined in kdb_cmds.  */
2925 static void __init kdb_cmd_init(void)
2926 {
2927         int i, diag;
2928         for (i = 0; kdb_cmds[i]; ++i) {
2929                 diag = kdb_parse(kdb_cmds[i]);
2930                 if (diag)
2931                         kdb_printf("kdb command %s failed, kdb diag %d\n",
2932                                 kdb_cmds[i], diag);
2933         }
2934         if (defcmd_in_progress) {
2935                 kdb_printf("Incomplete 'defcmd' set, forcing endefcmd\n");
2936                 kdb_parse("endefcmd");
2937         }
2938 }
2939
2940 /* Intialize kdb_printf, breakpoint tables and kdb state */
2941 void __init kdb_init(int lvl)
2942 {
2943         static int kdb_init_lvl = KDB_NOT_INITIALIZED;
2944         int i;
2945
2946         if (kdb_init_lvl == KDB_INIT_FULL || lvl <= kdb_init_lvl)
2947                 return;
2948         for (i = kdb_init_lvl; i < lvl; i++) {
2949                 switch (i) {
2950                 case KDB_NOT_INITIALIZED:
2951                         kdb_inittab();          /* Initialize Command Table */
2952                         kdb_initbptab();        /* Initialize Breakpoints */
2953                         break;
2954                 case KDB_INIT_EARLY:
2955                         kdb_cmd_init();         /* Build kdb_cmds tables */
2956                         break;
2957                 }
2958         }
2959         kdb_init_lvl = lvl;
2960 }