123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136 |
- #ifndef _LINUX_HW_BREAKPOINT_H
- #define _LINUX_HW_BREAKPOINT_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;
- };
- /*
- * 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.
- */
- 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 unsigned int hbp_kernel_pos;
- #endif /* __KERNEL__ */
- #endif /* _LINUX_HW_BREAKPOINT_H */
|