1 #ifndef _KDB_H
2 #define _KDB_H
3 
4 /*
5  * Kernel Debugger Architecture Independent Global Headers
6  *
7  * This file is subject to the terms and conditions of the GNU General Public
8  * License.  See the file "COPYING" in the main directory of this archive
9  * for more details.
10  *
11  * Copyright (c) 2000-2007 Silicon Graphics, Inc.  All Rights Reserved.
12  * Copyright (C) 2000 Stephane Eranian <eranian@hpl.hp.com>
13  * Copyright (C) 2009 Jason Wessel <jason.wessel@windriver.com>
14  */
15 
16 #include <linux/list.h>
17 
18 /* Shifted versions of the command enable bits are be used if the command
19  * has no arguments (see kdb_check_flags). This allows commands, such as
20  * go, to have different permissions depending upon whether it is called
21  * with an argument.
22  */
23 #define KDB_ENABLE_NO_ARGS_SHIFT 10
24 
25 typedef enum {
26 	KDB_ENABLE_ALL = (1 << 0), /* Enable everything */
27 	KDB_ENABLE_MEM_READ = (1 << 1),
28 	KDB_ENABLE_MEM_WRITE = (1 << 2),
29 	KDB_ENABLE_REG_READ = (1 << 3),
30 	KDB_ENABLE_REG_WRITE = (1 << 4),
31 	KDB_ENABLE_INSPECT = (1 << 5),
32 	KDB_ENABLE_FLOW_CTRL = (1 << 6),
33 	KDB_ENABLE_SIGNAL = (1 << 7),
34 	KDB_ENABLE_REBOOT = (1 << 8),
35 	/* User exposed values stop here, all remaining flags are
36 	 * exclusively used to describe a commands behaviour.
37 	 */
38 
39 	KDB_ENABLE_ALWAYS_SAFE = (1 << 9),
40 	KDB_ENABLE_MASK = (1 << KDB_ENABLE_NO_ARGS_SHIFT) - 1,
41 
42 	KDB_ENABLE_ALL_NO_ARGS = KDB_ENABLE_ALL << KDB_ENABLE_NO_ARGS_SHIFT,
43 	KDB_ENABLE_MEM_READ_NO_ARGS = KDB_ENABLE_MEM_READ
44 				      << KDB_ENABLE_NO_ARGS_SHIFT,
45 	KDB_ENABLE_MEM_WRITE_NO_ARGS = KDB_ENABLE_MEM_WRITE
46 				       << KDB_ENABLE_NO_ARGS_SHIFT,
47 	KDB_ENABLE_REG_READ_NO_ARGS = KDB_ENABLE_REG_READ
48 				      << KDB_ENABLE_NO_ARGS_SHIFT,
49 	KDB_ENABLE_REG_WRITE_NO_ARGS = KDB_ENABLE_REG_WRITE
50 				       << KDB_ENABLE_NO_ARGS_SHIFT,
51 	KDB_ENABLE_INSPECT_NO_ARGS = KDB_ENABLE_INSPECT
52 				     << KDB_ENABLE_NO_ARGS_SHIFT,
53 	KDB_ENABLE_FLOW_CTRL_NO_ARGS = KDB_ENABLE_FLOW_CTRL
54 				       << KDB_ENABLE_NO_ARGS_SHIFT,
55 	KDB_ENABLE_SIGNAL_NO_ARGS = KDB_ENABLE_SIGNAL
56 				    << KDB_ENABLE_NO_ARGS_SHIFT,
57 	KDB_ENABLE_REBOOT_NO_ARGS = KDB_ENABLE_REBOOT
58 				    << KDB_ENABLE_NO_ARGS_SHIFT,
59 	KDB_ENABLE_ALWAYS_SAFE_NO_ARGS = KDB_ENABLE_ALWAYS_SAFE
60 					 << KDB_ENABLE_NO_ARGS_SHIFT,
61 	KDB_ENABLE_MASK_NO_ARGS = KDB_ENABLE_MASK << KDB_ENABLE_NO_ARGS_SHIFT,
62 
63 	KDB_REPEAT_NO_ARGS = 0x40000000, /* Repeat the command w/o arguments */
64 	KDB_REPEAT_WITH_ARGS = 0x80000000, /* Repeat the command with args */
65 } kdb_cmdflags_t;
66 
67 typedef int (*kdb_func_t)(int, const char **);
68 
69 /* The KDB shell command table */
70 typedef struct _kdbtab {
71 	char    *name;			/* Command name */
72 	kdb_func_t func;		/* Function to execute command */
73 	char    *usage;			/* Usage String for this command */
74 	char    *help;			/* Help message for this command */
75 	short    minlen;		/* Minimum legal # cmd chars required */
76 	kdb_cmdflags_t flags;		/* Command behaviour flags */
77 	struct list_head list_node;	/* Command list */
78 } kdbtab_t;
79 
80 #ifdef	CONFIG_KGDB_KDB
81 #include <linux/init.h>
82 #include <linux/sched.h>
83 #include <linux/atomic.h>
84 
85 #define KDB_POLL_FUNC_MAX	5
86 extern int kdb_poll_idx;
87 
88 /*
89  * kdb_initial_cpu is initialized to -1, and is set to the cpu
90  * number whenever the kernel debugger is entered.
91  */
92 extern int kdb_initial_cpu;
93 
94 /* Types and messages used for dynamically added kdb shell commands */
95 
96 #define KDB_MAXARGS    16 /* Maximum number of arguments to a function  */
97 
98 /* KDB return codes from a command or internal kdb function */
99 #define KDB_NOTFOUND	(-1)
100 #define KDB_ARGCOUNT	(-2)
101 #define KDB_BADWIDTH	(-3)
102 #define KDB_BADRADIX	(-4)
103 #define KDB_NOTENV	(-5)
104 #define KDB_NOENVVALUE	(-6)
105 #define KDB_NOTIMP	(-7)
106 #define KDB_ENVFULL	(-8)
107 #define KDB_ENVBUFFULL	(-9)
108 #define KDB_TOOMANYBPT	(-10)
109 #define KDB_TOOMANYDBREGS (-11)
110 #define KDB_DUPBPT	(-12)
111 #define KDB_BPTNOTFOUND	(-13)
112 #define KDB_BADMODE	(-14)
113 #define KDB_BADINT	(-15)
114 #define KDB_INVADDRFMT  (-16)
115 #define KDB_BADREG      (-17)
116 #define KDB_BADCPUNUM   (-18)
117 #define KDB_BADLENGTH	(-19)
118 #define KDB_NOBP	(-20)
119 #define KDB_BADADDR	(-21)
120 #define KDB_NOPERM	(-22)
121 
122 /*
123  * kdb_diemsg
124  *
125  *	Contains a pointer to the last string supplied to the
126  *	kernel 'die' panic function.
127  */
128 extern const char *kdb_diemsg;
129 
130 #define KDB_FLAG_EARLYKDB	(1 << 0) /* set from boot parameter kdb=early */
131 #define KDB_FLAG_CATASTROPHIC	(1 << 1) /* A catastrophic event has occurred */
132 #define KDB_FLAG_CMD_INTERRUPT	(1 << 2) /* Previous command was interrupted */
133 #define KDB_FLAG_NOIPI		(1 << 3) /* Do not send IPIs */
134 #define KDB_FLAG_NO_CONSOLE	(1 << 5) /* No console is available,
135 					  * kdb is disabled */
136 #define KDB_FLAG_NO_VT_CONSOLE	(1 << 6) /* No VT console is available, do
137 					  * not use keyboard */
138 #define KDB_FLAG_NO_I8042	(1 << 7) /* No i8042 chip is available, do
139 					  * not use keyboard */
140 
141 extern unsigned int kdb_flags;	/* Global flags, see kdb_state for per cpu state */
142 
143 extern void kdb_save_flags(void);
144 extern void kdb_restore_flags(void);
145 
146 #define KDB_FLAG(flag)		(kdb_flags & KDB_FLAG_##flag)
147 #define KDB_FLAG_SET(flag)	((void)(kdb_flags |= KDB_FLAG_##flag))
148 #define KDB_FLAG_CLEAR(flag)	((void)(kdb_flags &= ~KDB_FLAG_##flag))
149 
150 /*
151  * External entry point for the kernel debugger.  The pt_regs
152  * at the time of entry are supplied along with the reason for
153  * entry to the kernel debugger.
154  */
155 
156 typedef enum {
157 	KDB_REASON_ENTER = 1,	/* KDB_ENTER() trap/fault - regs valid */
158 	KDB_REASON_ENTER_SLAVE,	/* KDB_ENTER_SLAVE() trap/fault - regs valid */
159 	KDB_REASON_BREAK,	/* Breakpoint inst. - regs valid */
160 	KDB_REASON_DEBUG,	/* Debug Fault - regs valid */
161 	KDB_REASON_OOPS,	/* Kernel Oops - regs valid */
162 	KDB_REASON_SWITCH,	/* CPU switch - regs valid*/
163 	KDB_REASON_KEYBOARD,	/* Keyboard entry - regs valid */
164 	KDB_REASON_NMI,		/* Non-maskable interrupt; regs valid */
165 	KDB_REASON_RECURSE,	/* Recursive entry to kdb;
166 				 * regs probably valid */
167 	KDB_REASON_SSTEP,	/* Single Step trap. - regs valid */
168 	KDB_REASON_SYSTEM_NMI,	/* In NMI due to SYSTEM cmd; regs valid */
169 } kdb_reason_t;
170 
171 enum kdb_msgsrc {
172 	KDB_MSGSRC_INTERNAL, /* direct call to kdb_printf() */
173 	KDB_MSGSRC_PRINTK, /* trapped from printk() */
174 };
175 
176 extern int kdb_trap_printk;
177 extern int kdb_printf_cpu;
178 extern __printf(2, 0) int vkdb_printf(enum kdb_msgsrc src, const char *fmt,
179 				      va_list args);
180 extern __printf(1, 2) int kdb_printf(const char *, ...);
181 typedef __printf(1, 2) int (*kdb_printf_t)(const char *, ...);
182 
183 extern void kdb_init(int level);
184 
185 /* Access to kdb specific polling devices */
186 typedef int (*get_char_func)(void);
187 extern get_char_func kdb_poll_funcs[];
188 extern int kdb_get_kbd_char(void);
189 
190 static inline
kdb_process_cpu(const struct task_struct * p)191 int kdb_process_cpu(const struct task_struct *p)
192 {
193 	unsigned int cpu = task_cpu(p);
194 	if (cpu > num_possible_cpus())
195 		cpu = 0;
196 	return cpu;
197 }
198 
199 #ifdef CONFIG_KALLSYMS
200 extern const char *kdb_walk_kallsyms(loff_t *pos);
201 #else /* ! CONFIG_KALLSYMS */
kdb_walk_kallsyms(loff_t * pos)202 static inline const char *kdb_walk_kallsyms(loff_t *pos)
203 {
204 	return NULL;
205 }
206 #endif /* ! CONFIG_KALLSYMS */
207 
208 /* Dynamic kdb shell command registration */
209 extern int kdb_register(kdbtab_t *cmd);
210 extern void kdb_unregister(kdbtab_t *cmd);
211 #else /* ! CONFIG_KGDB_KDB */
kdb_printf(const char * fmt,...)212 static inline __printf(1, 2) int kdb_printf(const char *fmt, ...) { return 0; }
kdb_init(int level)213 static inline void kdb_init(int level) {}
kdb_register(kdbtab_t * cmd)214 static inline int kdb_register(kdbtab_t *cmd) { return 0; }
kdb_unregister(kdbtab_t * cmd)215 static inline void kdb_unregister(kdbtab_t *cmd) {}
216 #endif	/* CONFIG_KGDB_KDB */
217 enum {
218 	KDB_NOT_INITIALIZED,
219 	KDB_INIT_EARLY,
220 	KDB_INIT_FULL,
221 };
222 
223 extern int kdbgetintenv(const char *, int *);
224 extern int kdb_set(int, const char **);
225 
226 #endif	/* !_KDB_H */
227