diff options
Diffstat (limited to 'include/linux/hw_breakpoint.h')
| -rw-r--r-- | include/linux/hw_breakpoint.h | 243 |
1 files changed, 119 insertions, 124 deletions
diff --git a/include/linux/hw_breakpoint.h b/include/linux/hw_breakpoint.h index 61ccc8f17eac..7eba9b92e5f3 100644 --- a/include/linux/hw_breakpoint.h +++ b/include/linux/hw_breakpoint.h @@ -1,136 +1,131 @@ #ifndef _LINUX_HW_BREAKPOINT_H #define _LINUX_HW_BREAKPOINT_H +#include <linux/perf_event.h> -#ifdef __KERNEL__ -#include <linux/list.h> -#include <linux/types.h> -#include <linux/kallsyms.h> - -/** - * struct hw_breakpoint - unified kernel/user-space hardware breakpoint - * @triggered: callback invoked after target address access - * @info: arch-specific breakpoint info (address, length, and type) - * - * %hw_breakpoint structures are the kernel's way of representing - * hardware breakpoints. These are data breakpoints - * (also known as "watchpoints", triggered on data access), and the breakpoint's - * target address can be located in either kernel space or user space. - * - * The breakpoint's address, length, and type are highly - * architecture-specific. The values are encoded in the @info field; you - * specify them when registering the breakpoint. To examine the encoded - * values use hw_breakpoint_get_{kaddress,uaddress,len,type}(), declared - * below. - * - * The address is specified as a regular kernel pointer (for kernel-space - * breakponts) or as an %__user pointer (for user-space breakpoints). - * With register_user_hw_breakpoint(), the address must refer to a - * location in user space. The breakpoint will be active only while the - * requested task is running. Conversely with - * register_kernel_hw_breakpoint(), the address must refer to a location - * in kernel space, and the breakpoint will be active on all CPUs - * regardless of the current task. - * - * The length is the breakpoint's extent in bytes, which is subject to - * certain limitations. include/asm/hw_breakpoint.h contains macros - * defining the available lengths for a specific architecture. Note that - * the address's alignment must match the length. The breakpoint will - * catch accesses to any byte in the range from address to address + - * (length - 1). - * - * The breakpoint's type indicates the sort of access that will cause it - * to trigger. Possible values may include: - * - * %HW_BREAKPOINT_RW (triggered on read or write access), - * %HW_BREAKPOINT_WRITE (triggered on write access), and - * %HW_BREAKPOINT_READ (triggered on read access). - * - * Appropriate macros are defined in include/asm/hw_breakpoint.h; not all - * possibilities are available on all architectures. Execute breakpoints - * must have length equal to the special value %HW_BREAKPOINT_LEN_EXECUTE. - * - * When a breakpoint gets hit, the @triggered callback is - * invoked in_interrupt with a pointer to the %hw_breakpoint structure and the - * processor registers. - * Data breakpoints occur after the memory access has taken place. - * Breakpoints are disabled during execution @triggered, to avoid - * recursive traps and allow unhindered access to breakpointed memory. - * - * This sample code sets a breakpoint on pid_max and registers a callback - * function for writes to that variable. Note that it is not portable - * as written, because not all architectures support HW_BREAKPOINT_LEN_4. - * - * ---------------------------------------------------------------------- - * - * #include <asm/hw_breakpoint.h> - * - * struct hw_breakpoint my_bp; - * - * static void my_triggered(struct hw_breakpoint *bp, struct pt_regs *regs) - * { - * printk(KERN_DEBUG "Inside triggered routine of breakpoint exception\n"); - * dump_stack(); - * .......<more debugging output>........ - * } - * - * static struct hw_breakpoint my_bp; - * - * static int init_module(void) - * { - * ..........<do anything>............ - * my_bp.info.type = HW_BREAKPOINT_WRITE; - * my_bp.info.len = HW_BREAKPOINT_LEN_4; - * - * my_bp.installed = (void *)my_bp_installed; - * - * rc = register_kernel_hw_breakpoint(&my_bp); - * ..........<do anything>............ - * } - * - * static void cleanup_module(void) - * { - * ..........<do anything>............ - * unregister_kernel_hw_breakpoint(&my_bp); - * ..........<do anything>............ - * } - * - * ---------------------------------------------------------------------- - */ -struct hw_breakpoint { - void (*triggered)(struct hw_breakpoint *, struct pt_regs *); - struct arch_hw_breakpoint info; +enum { + HW_BREAKPOINT_LEN_1 = 1, + HW_BREAKPOINT_LEN_2 = 2, + HW_BREAKPOINT_LEN_4 = 4, + HW_BREAKPOINT_LEN_8 = 8, }; -/* - * len and type values are defined in include/asm/hw_breakpoint.h. - * Available values vary according to the architecture. On i386 the - * possibilities are: - * - * HW_BREAKPOINT_LEN_1 - * HW_BREAKPOINT_LEN_2 - * HW_BREAKPOINT_LEN_4 - * HW_BREAKPOINT_RW - * HW_BREAKPOINT_READ - * - * On other architectures HW_BREAKPOINT_LEN_8 may be available, and the - * 1-, 2-, and 4-byte lengths may be unavailable. There also may be - * HW_BREAKPOINT_WRITE. You can use #ifdef to check at compile time. - */ +enum { + HW_BREAKPOINT_R = 1, + HW_BREAKPOINT_W = 2, + HW_BREAKPOINT_X = 4, +}; + +static inline struct arch_hw_breakpoint *counter_arch_bp(struct perf_event *bp) +{ + return &bp->hw.info; +} + +static inline unsigned long hw_breakpoint_addr(struct perf_event *bp) +{ + return bp->attr.bp_addr; +} + +static inline int hw_breakpoint_type(struct perf_event *bp) +{ + return bp->attr.bp_type; +} + +static inline int hw_breakpoint_len(struct perf_event *bp) +{ + return bp->attr.bp_len; +} + +#ifdef CONFIG_HAVE_HW_BREAKPOINT +extern struct perf_event * +register_user_hw_breakpoint(unsigned long addr, + int len, + int type, + perf_callback_t triggered, + struct task_struct *tsk, + bool active); + +/* FIXME: only change from the attr, and don't unregister */ +extern struct perf_event * +modify_user_hw_breakpoint(struct perf_event *bp, + unsigned long addr, + int len, + int type, + perf_callback_t triggered, + struct task_struct *tsk, + bool active); -extern int register_user_hw_breakpoint(struct task_struct *tsk, - struct hw_breakpoint *bp); -extern int modify_user_hw_breakpoint(struct task_struct *tsk, - struct hw_breakpoint *bp); -extern void unregister_user_hw_breakpoint(struct task_struct *tsk, - struct hw_breakpoint *bp); /* * Kernel breakpoints are not associated with any particular thread. */ -extern int register_kernel_hw_breakpoint(struct hw_breakpoint *bp); -extern void unregister_kernel_hw_breakpoint(struct hw_breakpoint *bp); +extern struct perf_event * +register_wide_hw_breakpoint_cpu(unsigned long addr, + int len, + int type, + perf_callback_t triggered, + int cpu, + bool active); + +extern struct perf_event ** +register_wide_hw_breakpoint(unsigned long addr, + int len, + int type, + perf_callback_t triggered, + bool active); + +extern int register_perf_hw_breakpoint(struct perf_event *bp); +extern int __register_perf_hw_breakpoint(struct perf_event *bp); +extern void unregister_hw_breakpoint(struct perf_event *bp); +extern void unregister_wide_hw_breakpoint(struct perf_event **cpu_events); + +extern int reserve_bp_slot(struct perf_event *bp); +extern void release_bp_slot(struct perf_event *bp); + +extern void flush_ptrace_hw_breakpoint(struct task_struct *tsk); + +#else /* !CONFIG_HAVE_HW_BREAKPOINT */ + +static inline struct perf_event * +register_user_hw_breakpoint(unsigned long addr, + int len, + int type, + perf_callback_t triggered, + struct task_struct *tsk, + bool active) { return NULL; } +static inline struct perf_event * +modify_user_hw_breakpoint(struct perf_event *bp, + unsigned long addr, + int len, + int type, + perf_callback_t triggered, + struct task_struct *tsk, + bool active) { return NULL; } +static inline struct perf_event * +register_wide_hw_breakpoint_cpu(unsigned long addr, + int len, + int type, + perf_callback_t triggered, + int cpu, + bool active) { return NULL; } +static inline struct perf_event ** +register_wide_hw_breakpoint(unsigned long addr, + int len, + int type, + perf_callback_t triggered, + bool active) { return NULL; } +static inline int +register_perf_hw_breakpoint(struct perf_event *bp) { return -ENOSYS; } +static inline int +__register_perf_hw_breakpoint(struct perf_event *bp) { return -ENOSYS; } +static inline void unregister_hw_breakpoint(struct perf_event *bp) { } +static inline void +unregister_wide_hw_breakpoint(struct perf_event **cpu_events) { } +static inline int +reserve_bp_slot(struct perf_event *bp) {return -ENOSYS; } +static inline void release_bp_slot(struct perf_event *bp) { } + +static inline void flush_ptrace_hw_breakpoint(struct task_struct *tsk) { } -extern unsigned int hbp_kernel_pos; +#endif /* CONFIG_HAVE_HW_BREAKPOINT */ -#endif /* __KERNEL__ */ -#endif /* _LINUX_HW_BREAKPOINT_H */ +#endif /* _LINUX_HW_BREAKPOINT_H */ |