diff options
Diffstat (limited to 'kernel/include/linux/kgdb.h')
| -rw-r--r-- | kernel/include/linux/kgdb.h | 327 |
1 files changed, 327 insertions, 0 deletions
diff --git a/kernel/include/linux/kgdb.h b/kernel/include/linux/kgdb.h new file mode 100644 index 000000000..e465bb159 --- /dev/null +++ b/kernel/include/linux/kgdb.h @@ -0,0 +1,327 @@ +/* + * 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/linkage.h> +#include <linux/init.h> +#include <linux/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); + +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, + BP_POKE_BREAKPOINT, +}; + +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; +}; + +struct dbg_reg_def_t { + char *name; + int size; + int offset; +}; + +#ifndef DBG_MAX_REG_NUM +#define DBG_MAX_REG_NUM 0 +#else +extern struct dbg_reg_def_t dbg_reg_def[]; +extern char *dbg_get_reg(int regno, void *mem, struct pt_regs *regs); +extern int dbg_set_reg(int regno, void *mem, struct pt_regs *regs); +#endif +#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(struct kgdb_bkpt *bpt); +extern int kgdb_arch_remove_breakpoint(struct kgdb_bkpt *bpt); + +/** + * kgdb_arch_late - Perform any architecture specific initalization. + * + * This function will handle the late initalization of any + * architecture specific callbacks. This is an optional function for + * handling things like late initialization of hw breakpoints. The + * default implementation does nothing. + */ +extern void kgdb_arch_late(void); + + +/** + * 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. + * @disable_hw_break: Allow an architecture to specify how to disable + * hardware breakpoints for a single cpu. + * @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. + * @enable_nmi: Manage NMI-triggered entry to KGDB + */ +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 (*disable_hw_break)(struct pt_regs *regs); + void (*remove_all_hw_break)(void); + void (*correct_hw_break)(void); + + void (*enable_nmi)(bool on); +}; + +/** + * 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. + * @is_console: 1 if the end device is a console 0 if the I/O device is + * not a console + */ +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); + int is_console; +}; + +extern struct kgdb_arch arch_kgdb_ops; + +extern unsigned long kgdb_arch_pc(int exception, struct pt_regs *regs); + +#ifdef CONFIG_SERIAL_KGDB_NMI +extern int kgdb_register_nmi_console(void); +extern int kgdb_unregister_nmi_console(void); +extern bool kgdb_nmi_poll_knock(void); +#else +static inline int kgdb_register_nmi_console(void) { return 0; } +static inline int kgdb_unregister_nmi_console(void) { return 0; } +static inline bool kgdb_nmi_poll_knock(void) { return 1; } +#endif + +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 char *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 void kgdb_schedule_breakpoint(void); + +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_nmicallin(int cpu, int trapnr, void *regs, int err_code, + atomic_t *snd_rdy); +extern void gdbstub_exit(int status); + +extern int kgdb_single_step; +extern atomic_t kgdb_active; +#define in_dbg_master() \ + (raw_smp_processor_id() == atomic_read(&kgdb_active)) +extern bool dbg_is_early; +extern void __init dbg_late_init(void); +#else /* ! CONFIG_KGDB */ +#define in_dbg_master() (0) +#define dbg_late_init() +#endif /* ! CONFIG_KGDB */ +#endif /* _KGDB_H_ */ |