This patch introduces virtual debug registers to used by the per-thread
structure and wrapper routines to manage debug registers by process-related
functions.
Signed-off-by: K.Prasad <[email protected]>
Signed-off-by: Alan Stern <[email protected]>
---
arch/x86/include/asm/debugreg.h | 23 +++++++++++++++++++++++
arch/x86/include/asm/processor.h | 16 +++++++++-------
2 files changed, 32 insertions(+), 7 deletions(-)
Index: linux-2.6-tip.hbkpt/arch/x86/include/asm/debugreg.h
===================================================================
--- linux-2.6-tip.hbkpt.orig/arch/x86/include/asm/debugreg.h
+++ linux-2.6-tip.hbkpt/arch/x86/include/asm/debugreg.h
@@ -49,6 +49,8 @@
#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 +69,25 @@
#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 */
+void flush_thread_hw_breakpoint(struct task_struct *tsk);
+int copy_thread_hw_breakpoint(struct task_struct *tsk,
+ struct task_struct *child, unsigned long clone_flags);
+void dump_thread_hw_breakpoint(struct task_struct *tsk, int u_debugreg[8]);
+void switch_to_thread_hw_breakpoint(struct task_struct *tsk);
+
+/* For CPU management */
+void load_debug_registers(void);
+static inline void hw_breakpoint_disable(void)
+{
+ set_debugreg(0UL, 7);
+}
+
+#endif /* __KERNEL__ */
+
#endif /* _ASM_X86_DEBUGREG_H */
Index: linux-2.6-tip.hbkpt/arch/x86/include/asm/processor.h
===================================================================
--- linux-2.6-tip.hbkpt.orig/arch/x86/include/asm/processor.h
+++ linux-2.6-tip.hbkpt/arch/x86/include/asm/processor.h
@@ -29,6 +29,7 @@ struct mm_struct;
#include <linux/threads.h>
#include <linux/init.h>
+#define HB_NUM 4
/*
* Default implementation of macro that returns current
* instruction pointer ("program counter").
@@ -424,13 +425,14 @@ struct thread_struct {
unsigned long ip;
unsigned long fs;
unsigned long gs;
- /* Hardware debugging registers: */
- unsigned long debugreg0;
- unsigned long debugreg1;
- unsigned long debugreg2;
- unsigned long debugreg3;
- unsigned long debugreg6;
- unsigned long debugreg7;
+ /* Hardware breakpoint info */
+ struct hw_breakpoint *hbkpt[HB_NUM];
+ unsigned int hbkpt_num_installed;
+ /* Thread's view of debug reg 6 */
+ unsigned long dr6;
+ /* Thread's view of debug reg 7 */
+ unsigned long dr7;
+
/* Fault info: */
unsigned long cr2;
unsigned long trap_no;