Blackfin: initial tracehook support

Signed-off-by: Mike Frysinger <vapier@gentoo.org>

1 files changed, 23 insertions, 0 deletions

diff --git a/arch/blackfin/include/asm/ptrace.h b/arch/blackfin/include/asm/ptrace.h
index c1aebdb981c7..aaa1c6c2bc19 100644
--- a/arch/blackfin/include/asm/ptrace.h
+++ b/arch/blackfin/include/asm/ptrace.h
@@ -24,6 +24,8 @@
 
 #ifndef __ASSEMBLY__
 
+struct task_struct;
+
 /* this struct defines the way the registers are stored on the
    stack during a system call. */
 
@@ -101,9 +103,30 @@ struct pt_regs {
    master interrupt enable.  */
 #define user_mode(regs) (!(((regs)->ipend & ~0x10) & (((regs)->ipend & ~0x10) - 1)))
 #define instruction_pointer(regs) ((regs)->pc)
+#define user_stack_pointer(regs)  ((regs)->usp)
 #define profile_pc(regs) instruction_pointer(regs)
 extern void show_regs(struct pt_regs *);
 
+#define arch_has_single_step()  (1)
+extern void user_enable_single_step(struct task_struct *child);
+extern void user_disable_single_step(struct task_struct *child);
+/* common code demands this function */
+#define ptrace_disable(child) user_disable_single_step(child)
+
+/*
+ * Get the address of the live pt_regs for the specified task.
+ * These are saved onto the top kernel stack when the process
+ * is not running.
+ *
+ * Note: if a user thread is execve'd from kernel space, the
+ * kernel stack will not be empty on entry to the kernel, so
+ * ptracing these tasks will fail.
+ */
+#define task_pt_regs(task) \
+        (struct pt_regs *) \
+            ((unsigned long)task_stack_page(task) + \
+             (THREAD_SIZE - sizeof(struct pt_regs)))
+
 #endif  /*  __KERNEL__  */
 
 #endif                          /* __ASSEMBLY__ */