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