[net-next-2.6.git] / include / linux / kgdb.h

/*
 * This provides the callbacks and functions that KGDB needs to share between
 * the core, I/O and arch-specific portions.
 *
 * Author: Amit Kale <amitkale@linsyssoft.com> and
 *         Tom Rini <trini@kernel.crashing.org>
 *
 * 2001-2004 (c) Amit S. Kale and 2003-2005 (c) MontaVista Software, Inc.
 * This file is licensed under the terms of the GNU General Public License
 * version 2. This program is licensed "as is" without any warranty of any
 * kind, whether express or implied.
 */
#ifndef _KGDB_H_
#define _KGDB_H_

#include <linux/serial_8250.h>
#include <linux/linkage.h>
#include <linux/init.h>
#include <asm/atomic.h>
#ifdef CONFIG_HAVE_ARCH_KGDB
#include <asm/kgdb.h>
#endif

#ifdef CONFIG_KGDB
struct pt_regs;

/**
 *	kgdb_skipexception - (optional) exit kgdb_handle_exception early
 *	@exception: Exception vector number
 *	@regs: Current &struct pt_regs.
 *
 *	On some architectures it is required to skip a breakpoint
 *	exception when it occurs after a breakpoint has been removed.
 *	This can be implemented in the architecture specific portion of kgdb.
 */
extern int kgdb_skipexception(int exception, struct pt_regs *regs);

/**
 *	kgdb_disable_hw_debug - (optional) Disable hardware debugging hook
 *	@regs: Current &struct pt_regs.
 *
 *	This function will be called if the particular architecture must
 *	disable hardware debugging while it is processing gdb packets or
 *	handling exception.
 */
extern void kgdb_disable_hw_debug(struct pt_regs *regs);

struct tasklet_struct;
struct task_struct;
struct uart_port;

/**
 *	kgdb_breakpoint - compiled in breakpoint
 *
 *	This will be implemented as a static inline per architecture.  This
 *	function is called by the kgdb core to execute an architecture
 *	specific trap to cause kgdb to enter the exception processing.
 *
 */
void kgdb_breakpoint(void);

extern int kgdb_connected;
extern int kgdb_io_module_registered;

extern atomic_t			kgdb_setting_breakpoint;
extern atomic_t			kgdb_cpu_doing_single_step;

extern struct task_struct	*kgdb_usethread;
extern struct task_struct	*kgdb_contthread;

enum kgdb_bptype {
	BP_BREAKPOINT = 0,
	BP_HARDWARE_BREAKPOINT,
	BP_WRITE_WATCHPOINT,
	BP_READ_WATCHPOINT,
	BP_ACCESS_WATCHPOINT
};

enum kgdb_bpstate {
	BP_UNDEFINED = 0,
	BP_REMOVED,
	BP_SET,
	BP_ACTIVE
};

struct kgdb_bkpt {
	unsigned long		bpt_addr;
	unsigned char		saved_instr[BREAK_INSTR_SIZE];
	enum kgdb_bptype	type;
	enum kgdb_bpstate	state;
};

#ifndef KGDB_MAX_BREAKPOINTS
# define KGDB_MAX_BREAKPOINTS	1000
#endif

#define KGDB_HW_BREAKPOINT	1

/*
 * Functions each KGDB-supporting architecture must provide:
 */

/**
 *	kgdb_arch_init - Perform any architecture specific initalization.
 *
 *	This function will handle the initalization of any architecture
 *	specific callbacks.
 */
extern int kgdb_arch_init(void);

/**
 *	kgdb_arch_exit - Perform any architecture specific uninitalization.
 *
 *	This function will handle the uninitalization of any architecture
 *	specific callbacks, for dynamic registration and unregistration.
 */
extern void kgdb_arch_exit(void);

/**
 *	pt_regs_to_gdb_regs - Convert ptrace regs to GDB regs
 *	@gdb_regs: A pointer to hold the registers in the order GDB wants.
 *	@regs: The &struct pt_regs of the current process.
 *
 *	Convert the pt_regs in @regs into the format for registers that
 *	GDB expects, stored in @gdb_regs.
 */
extern void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs);

/**
 *	sleeping_thread_to_gdb_regs - Convert ptrace regs to GDB regs
 *	@gdb_regs: A pointer to hold the registers in the order GDB wants.
 *	@p: The &struct task_struct of the desired process.
 *
 *	Convert the register values of the sleeping process in @p to
 *	the format that GDB expects.
 *	This function is called when kgdb does not have access to the
 *	&struct pt_regs and therefore it should fill the gdb registers
 *	@gdb_regs with what has	been saved in &struct thread_struct
 *	thread field during switch_to.
 */
extern void
sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p);

/**
 *	gdb_regs_to_pt_regs - Convert GDB regs to ptrace regs.
 *	@gdb_regs: A pointer to hold the registers we've received from GDB.
 *	@regs: A pointer to a &struct pt_regs to hold these values in.
 *
 *	Convert the GDB regs in @gdb_regs into the pt_regs, and store them
 *	in @regs.
 */
extern void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs);

/**
 *	kgdb_arch_handle_exception - Handle architecture specific GDB packets.
 *	@vector: The error vector of the exception that happened.
 *	@signo: The signal number of the exception that happened.
 *	@err_code: The error code of the exception that happened.
 *	@remcom_in_buffer: The buffer of the packet we have read.
 *	@remcom_out_buffer: The buffer of %BUFMAX bytes to write a packet into.
 *	@regs: The &struct pt_regs of the current process.
 *
 *	This function MUST handle the 'c' and 's' command packets,
 *	as well packets to set / remove a hardware breakpoint, if used.
 *	If there are additional packets which the hardware needs to handle,
 *	they are handled here.  The code should return -1 if it wants to
 *	process more packets, and a %0 or %1 if it wants to exit from the
 *	kgdb callback.
 */
extern int
kgdb_arch_handle_exception(int vector, int signo, int err_code,
			   char *remcom_in_buffer,
			   char *remcom_out_buffer,
			   struct pt_regs *regs);

/**
 *	kgdb_roundup_cpus - Get other CPUs into a holding pattern
 *	@flags: Current IRQ state
 *
 *	On SMP systems, we need to get the attention of the other CPUs
 *	and get them into a known state.  This should do what is needed
 *	to get the other CPUs to call kgdb_wait(). Note that on some arches,
 *	the NMI approach is not used for rounding up all the CPUs. For example,
 *	in case of MIPS, smp_call_function() is used to roundup CPUs. In
 *	this case, we have to make sure that interrupts are enabled before
 *	calling smp_call_function(). The argument to this function is
 *	the flags that will be used when restoring the interrupts. There is
 *	local_irq_save() call before kgdb_roundup_cpus().
 *
 *	On non-SMP systems, this is not called.
 */
extern void kgdb_roundup_cpus(unsigned long flags);

/**
 *	kgdb_arch_set_pc - Generic call back to the program counter
 *	@regs: Current &struct pt_regs.
 *  @pc: The new value for the program counter
 *
 *	This function handles updating the program counter and requires an
 *	architecture specific implementation.
 */
extern void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc);


/* Optional functions. */
extern int kgdb_validate_break_address(unsigned long addr);
extern int kgdb_arch_set_breakpoint(unsigned long addr, char *saved_instr);
extern int kgdb_arch_remove_breakpoint(unsigned long addr, char *bundle);

/**
 * struct kgdb_arch - Describe architecture specific values.
 * @gdb_bpt_instr: The instruction to trigger a breakpoint.
 * @flags: Flags for the breakpoint, currently just %KGDB_HW_BREAKPOINT.
 * @set_breakpoint: Allow an architecture to specify how to set a software
 * breakpoint.
 * @remove_breakpoint: Allow an architecture to specify how to remove a
 * software breakpoint.
 * @set_hw_breakpoint: Allow an architecture to specify how to set a hardware
 * breakpoint.
 * @remove_hw_breakpoint: Allow an architecture to specify how to remove a
 * hardware breakpoint.
 * @remove_all_hw_break: Allow an architecture to specify how to remove all
 * hardware breakpoints.
 * @correct_hw_break: Allow an architecture to specify how to correct the
 * hardware debug registers.
 */
struct kgdb_arch {
	unsigned char		gdb_bpt_instr[BREAK_INSTR_SIZE];
	unsigned long		flags;

	int	(*set_breakpoint)(unsigned long, char *);
	int	(*remove_breakpoint)(unsigned long, char *);
	int	(*set_hw_breakpoint)(unsigned long, int, enum kgdb_bptype);
	int	(*remove_hw_breakpoint)(unsigned long, int, enum kgdb_bptype);
	void	(*remove_all_hw_break)(void);
	void	(*correct_hw_break)(void);
};

/**
 * struct kgdb_io - Describe the interface for an I/O driver to talk with KGDB.
 * @name: Name of the I/O driver.
 * @read_char: Pointer to a function that will return one char.
 * @write_char: Pointer to a function that will write one char.
 * @flush: Pointer to a function that will flush any pending writes.
 * @init: Pointer to a function that will initialize the device.
 * @pre_exception: Pointer to a function that will do any prep work for
 * the I/O driver.
 * @post_exception: Pointer to a function that will do any cleanup work
 * for the I/O driver.
 */
struct kgdb_io {
	const char		*name;
	int			(*read_char) (void);
	void			(*write_char) (u8);
	void			(*flush) (void);
	int			(*init) (void);
	void			(*pre_exception) (void);
	void			(*post_exception) (void);
};

extern struct kgdb_arch		arch_kgdb_ops;

extern unsigned long __weak kgdb_arch_pc(int exception, struct pt_regs *regs);

extern int kgdb_register_io_module(struct kgdb_io *local_kgdb_io_ops);
extern void kgdb_unregister_io_module(struct kgdb_io *local_kgdb_io_ops);
extern struct kgdb_io *dbg_io_ops;

extern int kgdb_hex2long(char **ptr, unsigned long *long_val);
extern int kgdb_mem2hex(char *mem, char *buf, int count);
extern int kgdb_hex2mem(char *buf, char *mem, int count);

extern int kgdb_isremovedbreak(unsigned long addr);

extern int
kgdb_handle_exception(int ex_vector, int signo, int err_code,
		      struct pt_regs *regs);
extern int kgdb_nmicallback(int cpu, void *regs);

extern int			kgdb_single_step;
extern atomic_t			kgdb_active;
#define in_dbg_master() \
	(raw_smp_processor_id() == atomic_read(&kgdb_active))
#else /* ! CONFIG_KGDB */
#define in_dbg_master() (0)
#endif /* ! CONFIG_KGDB */
#endif /* _KGDB_H_ */
Commit	Line	Data
dc7d5527 JW	1	/*
	2	* This provides the callbacks and functions that KGDB needs to share between
	3	* the core, I/O and arch-specific portions.
	4	*
	5	* Author: Amit Kale <amitkale@linsyssoft.com> and
	6	* Tom Rini <trini@kernel.crashing.org>
	7	*
	8	* 2001-2004 (c) Amit S. Kale and 2003-2005 (c) MontaVista Software, Inc.
	9	* This file is licensed under the terms of the GNU General Public License
	10	* version 2. This program is licensed "as is" without any warranty of any
	11	* kind, whether express or implied.
	12	*/
	13	#ifndef _KGDB_H_
	14	#define _KGDB_H_
	15
	16	#include <linux/serial_8250.h>
	17	#include <linux/linkage.h>
	18	#include <linux/init.h>
dc7d5527	19	#include <asm/atomic.h>
dcc78711	20	#ifdef CONFIG_HAVE_ARCH_KGDB
dc7d5527	21	#include <asm/kgdb.h>
dcc78711	22	#endif
dc7d5527	23
dcc78711	24	#ifdef CONFIG_KGDB
dc7d5527 JW	25	struct pt_regs;
dc7d5527 JW	26
e3e2aaf7 JW	27	/**
e3e2aaf7 JW	28	* kgdb_skipexception - (optional) exit kgdb_handle_exception early
dc7d5527 JW	29	* @exception: Exception vector number
	30	* @regs: Current &struct pt_regs.
	31	*
e3e2aaf7 JW	32	* On some architectures it is required to skip a breakpoint
e3e2aaf7 JW	33	* exception when it occurs after a breakpoint has been removed.
b11e1eca	34	* This can be implemented in the architecture specific portion of kgdb.
dc7d5527 JW	35	*/
	36	extern int kgdb_skipexception(int exception, struct pt_regs *regs);
	37
e3e2aaf7 JW	38	/**
e3e2aaf7 JW	39	* kgdb_disable_hw_debug - (optional) Disable hardware debugging hook
dc7d5527 JW	40	* @regs: Current &struct pt_regs.
	41	*
	42	* This function will be called if the particular architecture must
	43	* disable hardware debugging while it is processing gdb packets or
	44	* handling exception.
	45	*/
	46	extern void kgdb_disable_hw_debug(struct pt_regs *regs);
	47
	48	struct tasklet_struct;
	49	struct task_struct;
	50	struct uart_port;
	51
e3e2aaf7 JW	52	/**
	53	* kgdb_breakpoint - compiled in breakpoint
	54	*
b11e1eca	55	* This will be implemented as a static inline per architecture. This
e3e2aaf7 JW	56	* function is called by the kgdb core to execute an architecture
	57	* specific trap to cause kgdb to enter the exception processing.
	58	*
	59	*/
dc7d5527 JW	60	void kgdb_breakpoint(void);
	61
	62	extern int kgdb_connected;
f503b5ae	63	extern int kgdb_io_module_registered;
dc7d5527 JW	64
	65	extern atomic_t kgdb_setting_breakpoint;
	66	extern atomic_t kgdb_cpu_doing_single_step;
	67
	68	extern struct task_struct *kgdb_usethread;
	69	extern struct task_struct *kgdb_contthread;
	70
	71	enum kgdb_bptype {
	72	BP_BREAKPOINT = 0,
	73	BP_HARDWARE_BREAKPOINT,
	74	BP_WRITE_WATCHPOINT,
	75	BP_READ_WATCHPOINT,
	76	BP_ACCESS_WATCHPOINT
	77	};
	78
	79	enum kgdb_bpstate {
	80	BP_UNDEFINED = 0,
	81	BP_REMOVED,
	82	BP_SET,
	83	BP_ACTIVE
	84	};
	85
	86	struct kgdb_bkpt {
	87	unsigned long bpt_addr;
	88	unsigned char saved_instr[BREAK_INSTR_SIZE];
	89	enum kgdb_bptype type;
	90	enum kgdb_bpstate state;
	91	};
	92
	93	#ifndef KGDB_MAX_BREAKPOINTS
	94	# define KGDB_MAX_BREAKPOINTS 1000
	95	#endif
	96
	97	#define KGDB_HW_BREAKPOINT 1
	98
	99	/*
	100	* Functions each KGDB-supporting architecture must provide:
	101	*/
	102
e3e2aaf7	103	/**
dc7d5527 JW	104	* kgdb_arch_init - Perform any architecture specific initalization.
	105	*
	106	* This function will handle the initalization of any architecture
	107	* specific callbacks.
	108	*/
	109	extern int kgdb_arch_init(void);
	110
e3e2aaf7	111	/**
dc7d5527 JW	112	* kgdb_arch_exit - Perform any architecture specific uninitalization.
	113	*
	114	* This function will handle the uninitalization of any architecture
	115	* specific callbacks, for dynamic registration and unregistration.
	116	*/
	117	extern void kgdb_arch_exit(void);
	118
e3e2aaf7	119	/**
dc7d5527 JW	120	* pt_regs_to_gdb_regs - Convert ptrace regs to GDB regs
	121	* @gdb_regs: A pointer to hold the registers in the order GDB wants.
	122	* @regs: The &struct pt_regs of the current process.
	123	*
	124	* Convert the pt_regs in @regs into the format for registers that
	125	* GDB expects, stored in @gdb_regs.
	126	*/
	127	extern void pt_regs_to_gdb_regs(unsigned long gdb_regs, struct pt_regs regs);
	128
e3e2aaf7	129	/**
dc7d5527 JW	130	* sleeping_thread_to_gdb_regs - Convert ptrace regs to GDB regs
	131	* @gdb_regs: A pointer to hold the registers in the order GDB wants.
	132	* @p: The &struct task_struct of the desired process.
	133	*
	134	* Convert the register values of the sleeping process in @p to
	135	* the format that GDB expects.
	136	* This function is called when kgdb does not have access to the
	137	* &struct pt_regs and therefore it should fill the gdb registers
	138	* @gdb_regs with what has been saved in &struct thread_struct
	139	* thread field during switch_to.
	140	*/
	141	extern void
	142	sleeping_thread_to_gdb_regs(unsigned long gdb_regs, struct task_struct p);
	143
e3e2aaf7	144	/**
dc7d5527 JW	145	* gdb_regs_to_pt_regs - Convert GDB regs to ptrace regs.
	146	* @gdb_regs: A pointer to hold the registers we've received from GDB.
	147	* @regs: A pointer to a &struct pt_regs to hold these values in.
	148	*
	149	* Convert the GDB regs in @gdb_regs into the pt_regs, and store them
	150	* in @regs.
	151	*/
	152	extern void gdb_regs_to_pt_regs(unsigned long gdb_regs, struct pt_regs regs);
	153
e3e2aaf7	154	/**
dc7d5527 JW	155	* kgdb_arch_handle_exception - Handle architecture specific GDB packets.
	156	* @vector: The error vector of the exception that happened.
	157	* @signo: The signal number of the exception that happened.
	158	* @err_code: The error code of the exception that happened.
	159	* @remcom_in_buffer: The buffer of the packet we have read.
	160	* @remcom_out_buffer: The buffer of %BUFMAX bytes to write a packet into.
	161	* @regs: The &struct pt_regs of the current process.
	162	*
	163	* This function MUST handle the 'c' and 's' command packets,
	164	* as well packets to set / remove a hardware breakpoint, if used.
	165	* If there are additional packets which the hardware needs to handle,
	166	* they are handled here. The code should return -1 if it wants to
	167	* process more packets, and a %0 or %1 if it wants to exit from the
	168	* kgdb callback.
	169	*/
	170	extern int
	171	kgdb_arch_handle_exception(int vector, int signo, int err_code,
	172	char *remcom_in_buffer,
	173	char *remcom_out_buffer,
	174	struct pt_regs *regs);
	175
e3e2aaf7	176	/**
dc7d5527 JW	177	* kgdb_roundup_cpus - Get other CPUs into a holding pattern
	178	* @flags: Current IRQ state
	179	*
	180	* On SMP systems, we need to get the attention of the other CPUs
b11e1eca	181	* and get them into a known state. This should do what is needed
dc7d5527 JW	182	* to get the other CPUs to call kgdb_wait(). Note that on some arches,
	183	* the NMI approach is not used for rounding up all the CPUs. For example,
	184	* in case of MIPS, smp_call_function() is used to roundup CPUs. In
	185	* this case, we have to make sure that interrupts are enabled before
	186	* calling smp_call_function(). The argument to this function is
	187	* the flags that will be used when restoring the interrupts. There is
	188	* local_irq_save() call before kgdb_roundup_cpus().
	189	*
	190	* On non-SMP systems, this is not called.
	191	*/
	192	extern void kgdb_roundup_cpus(unsigned long flags);
	193
84c08fd6 JW	194	/**
	195	* kgdb_arch_set_pc - Generic call back to the program counter
	196	* @regs: Current &struct pt_regs.
	197	* @pc: The new value for the program counter
	198	*
	199	* This function handles updating the program counter and requires an
	200	* architecture specific implementation.
	201	*/
	202	extern void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc);
	203
	204
dc7d5527 JW	205	/* Optional functions. */
	206	extern int kgdb_validate_break_address(unsigned long addr);
	207	extern int kgdb_arch_set_breakpoint(unsigned long addr, char *saved_instr);
	208	extern int kgdb_arch_remove_breakpoint(unsigned long addr, char *bundle);
	209
e3e2aaf7	210	/**
dc7d5527 JW	211	* struct kgdb_arch - Describe architecture specific values.
	212	* @gdb_bpt_instr: The instruction to trigger a breakpoint.
	213	* @flags: Flags for the breakpoint, currently just %KGDB_HW_BREAKPOINT.
	214	* @set_breakpoint: Allow an architecture to specify how to set a software
	215	* breakpoint.
	216	* @remove_breakpoint: Allow an architecture to specify how to remove a
	217	* software breakpoint.
	218	* @set_hw_breakpoint: Allow an architecture to specify how to set a hardware
	219	* breakpoint.
	220	* @remove_hw_breakpoint: Allow an architecture to specify how to remove a
	221	* hardware breakpoint.
	222	* @remove_all_hw_break: Allow an architecture to specify how to remove all
	223	* hardware breakpoints.
	224	* @correct_hw_break: Allow an architecture to specify how to correct the
	225	* hardware debug registers.
	226	*/
	227	struct kgdb_arch {
	228	unsigned char gdb_bpt_instr[BREAK_INSTR_SIZE];
	229	unsigned long flags;
	230
	231	int (set_breakpoint)(unsigned long, char );
	232	int (remove_breakpoint)(unsigned long, char );
	233	int (*set_hw_breakpoint)(unsigned long, int, enum kgdb_bptype);
	234	int (*remove_hw_breakpoint)(unsigned long, int, enum kgdb_bptype);
	235	void (*remove_all_hw_break)(void);
	236	void (*correct_hw_break)(void);
	237	};
	238
e3e2aaf7	239	/**
dc7d5527 JW	240	* struct kgdb_io - Describe the interface for an I/O driver to talk with KGDB.
	241	* @name: Name of the I/O driver.
	242	* @read_char: Pointer to a function that will return one char.
	243	* @write_char: Pointer to a function that will write one char.
	244	* @flush: Pointer to a function that will flush any pending writes.
	245	* @init: Pointer to a function that will initialize the device.
	246	* @pre_exception: Pointer to a function that will do any prep work for
	247	* the I/O driver.
	248	* @post_exception: Pointer to a function that will do any cleanup work
	249	* for the I/O driver.
	250	*/
	251	struct kgdb_io {
	252	const char *name;
	253	int (*read_char) (void);
	254	void (*write_char) (u8);
	255	void (*flush) (void);
	256	int (*init) (void);
	257	void (*pre_exception) (void);
	258	void (*post_exception) (void);
	259	};
	260
	261	extern struct kgdb_arch arch_kgdb_ops;
	262
688b744d HH	263	extern unsigned long __weak kgdb_arch_pc(int exception, struct pt_regs *regs);
688b744d HH	264
dc7d5527 JW	265	extern int kgdb_register_io_module(struct kgdb_io *local_kgdb_io_ops);
dc7d5527 JW	266	extern void kgdb_unregister_io_module(struct kgdb_io *local_kgdb_io_ops);
53197fc4	267	extern struct kgdb_io *dbg_io_ops;
dc7d5527	268
688b744d	269	extern int kgdb_hex2long(char *ptr, unsigned long long_val);
dc7d5527 JW	270	extern int kgdb_mem2hex(char mem, char buf, int count);
	271	extern int kgdb_hex2mem(char buf, char mem, int count);
	272
	273	extern int kgdb_isremovedbreak(unsigned long addr);
	274
	275	extern int
	276	kgdb_handle_exception(int ex_vector, int signo, int err_code,
	277	struct pt_regs *regs);
	278	extern int kgdb_nmicallback(int cpu, void *regs);
	279
	280	extern int kgdb_single_step;
	281	extern atomic_t kgdb_active;
dcc78711 JW	282	#define in_dbg_master() \
	283	(raw_smp_processor_id() == atomic_read(&kgdb_active))
	284	#else /* ! CONFIG_KGDB */
	285	#define in_dbg_master() (0)
	286	#endif /* ! CONFIG_KGDB */
dc7d5527	287	#endif /* _KGDB_H_ */