4 files changed, 92 insertions, 8 deletions

diff --git a/arch/x86/include/asm/a.out-core.h b/arch/x86/include/asm/a.out-core.h
index bb70e397aa84..fc4685dd6e4d 100644
--- a/arch/x86/include/asm/a.out-core.h
+++ b/arch/x86/include/asm/a.out-core.h
@@ -32,10 +32,10 @@ static inline void aout_dump_thread(struct pt_regs *regs, struct user *dump)
                         >> PAGE_SHIFT;
         dump->u_dsize -= dump->u_tsize;
         dump->u_ssize = 0;
-        dump->u_debugreg[0] = current->thread.debugreg0;
-        dump->u_debugreg[1] = current->thread.debugreg1;
-        dump->u_debugreg[2] = current->thread.debugreg2;
-        dump->u_debugreg[3] = current->thread.debugreg3;
+        dump->u_debugreg[0] = current->thread.debugreg[0];
+        dump->u_debugreg[1] = current->thread.debugreg[1];
+        dump->u_debugreg[2] = current->thread.debugreg[2];
+        dump->u_debugreg[3] = current->thread.debugreg[3];
         dump->u_debugreg[4] = 0;
         dump->u_debugreg[5] = 0;
         dump->u_debugreg[6] = current->thread.debugreg6;
diff --git a/arch/x86/include/asm/debugreg.h b/arch/x86/include/asm/debugreg.h
index 3ea6f37be9e2..23439fbb1d0e 100644
--- a/arch/x86/include/asm/debugreg.h
+++ b/arch/x86/include/asm/debugreg.h
@@ -18,6 +18,7 @@
 #define DR_TRAP1        (0x2)           /* db1 */
 #define DR_TRAP2        (0x4)           /* db2 */
 #define DR_TRAP3        (0x8)           /* db3 */
+#define DR_TRAP_BITS    (DR_TRAP0|DR_TRAP1|DR_TRAP2|DR_TRAP3)
 
 #define DR_STEP         (0x4000)        /* single-step */
 #define DR_SWITCH       (0x8000)        /* task switch */
@@ -49,6 +50,8 @@
 
 #define DR_LOCAL_ENABLE_SHIFT 0    /* Extra shift to the local enable bit */
 #define DR_GLOBAL_ENABLE_SHIFT 1   /* Extra shift to the global enable bit */
+#define DR_LOCAL_ENABLE (0x1)      /* Local enable for reg 0 */
+#define DR_GLOBAL_ENABLE (0x2)     /* Global enable for reg 0 */
 #define DR_ENABLE_SIZE 2           /* 2 enable bits per register */
 
 #define DR_LOCAL_ENABLE_MASK (0x55)  /* Set  local bits for all 4 regs */
@@ -67,4 +70,30 @@
 #define DR_LOCAL_SLOWDOWN (0x100)   /* Local slow the pipeline */
 #define DR_GLOBAL_SLOWDOWN (0x200)  /* Global slow the pipeline */
 
+/*
+ * HW breakpoint additions
+ */
+#ifdef __KERNEL__
+
+/* For process management */
+extern void flush_thread_hw_breakpoint(struct task_struct *tsk);
+extern int copy_thread_hw_breakpoint(struct task_struct *tsk,
+                struct task_struct *child, unsigned long clone_flags);
+
+/* For CPU management */
+extern void load_debug_registers(void);
+static inline void hw_breakpoint_disable(void)
+{
+        /* Zero the control register for HW Breakpoint */
+        set_debugreg(0UL, 7);
+
+        /* Zero-out the individual HW breakpoint address registers */
+        set_debugreg(0UL, 0);
+        set_debugreg(0UL, 1);
+        set_debugreg(0UL, 2);
+        set_debugreg(0UL, 3);
+}
+
+#endif  /* __KERNEL__ */
+
 #endif /* _ASM_X86_DEBUGREG_H */
diff --git a/arch/x86/include/asm/hw_breakpoint.h b/arch/x86/include/asm/hw_breakpoint.h
new file mode 100644
index 000000000000..1acb4d45de70
--- /dev/null
+++ b/arch/x86/include/asm/hw_breakpoint.h
@@ -0,0 +1,55 @@
+#ifndef _I386_HW_BREAKPOINT_H
+#define _I386_HW_BREAKPOINT_H
+
+#ifdef  __KERNEL__
+#define __ARCH_HW_BREAKPOINT_H
+
+struct arch_hw_breakpoint {
+        char            *name; /* Contains name of the symbol to set bkpt */
+        unsigned long   address;
+        u8              len;
+        u8              type;
+};
+
+#include <linux/kdebug.h>
+#include <asm-generic/hw_breakpoint.h>
+
+/* Available HW breakpoint length encodings */
+#define HW_BREAKPOINT_LEN_1             0x40
+#define HW_BREAKPOINT_LEN_2             0x44
+#define HW_BREAKPOINT_LEN_4             0x4c
+#define HW_BREAKPOINT_LEN_EXECUTE       0x40
+
+#ifdef CONFIG_X86_64
+#define HW_BREAKPOINT_LEN_8             0x48
+#endif
+
+/* Available HW breakpoint type encodings */
+
+/* trigger on instruction execute */
+#define HW_BREAKPOINT_EXECUTE   0x80
+/* trigger on memory write */
+#define HW_BREAKPOINT_WRITE     0x81
+/* trigger on memory read or write */
+#define HW_BREAKPOINT_RW        0x83
+
+/* Total number of available HW breakpoint registers */
+#define HBP_NUM 4
+
+extern struct hw_breakpoint *hbp_kernel[HBP_NUM];
+DECLARE_PER_CPU(struct hw_breakpoint*, this_hbp_kernel[HBP_NUM]);
+extern unsigned int hbp_user_refcount[HBP_NUM];
+
+extern void arch_install_thread_hw_breakpoint(struct task_struct *tsk);
+extern void arch_uninstall_thread_hw_breakpoint(void);
+extern int arch_check_va_in_userspace(unsigned long va, u8 hbp_len);
+extern int arch_validate_hwbkpt_settings(struct hw_breakpoint *bp,
+                                                struct task_struct *tsk);
+extern void arch_update_user_hw_breakpoint(int pos, struct task_struct *tsk);
+extern void arch_flush_thread_hw_breakpoint(struct task_struct *tsk);
+extern void arch_update_kernel_hw_breakpoint(void *);
+extern int hw_breakpoint_exceptions_notify(struct notifier_block *unused,
+                                     unsigned long val, void *data);
+#endif  /* __KERNEL__ */
+#endif  /* _I386_HW_BREAKPOINT_H */
+
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index c7768269b1cf..2b03f700d3f2 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -29,6 +29,7 @@ struct mm_struct;
 #include <linux/threads.h>
 #include <linux/init.h>
 
+#define HBP_NUM 4
 /*
  * Default implementation of macro that returns current
  * instruction pointer ("program counter").
@@ -433,12 +434,11 @@ struct thread_struct {
 #endif
         unsigned long           gs;
         /* Hardware debugging registers: */
-        unsigned long           debugreg0;
-        unsigned long           debugreg1;
-        unsigned long           debugreg2;
-        unsigned long           debugreg3;
+        unsigned long           debugreg[HBP_NUM];
         unsigned long           debugreg6;
         unsigned long           debugreg7;
+        /* Hardware breakpoint info */
+        struct hw_breakpoint    *hbp[HBP_NUM];
         /* Fault info: */
         unsigned long           cr2;
         unsigned long           trap_no;