x86: arch_has_single_step

This defines the new standard arch_has_single_step macro.  It makes the
existing set_singlestep and clear_singlestep entry points global, and
renames them to the new standard names user_enable_single_step and
user_disable_single_step, respectively.

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/x86/kernel/ptrace_32.c

@@ -218,7 +218,7 @@ static inline int is_setting_trap_flag(struct task_struct *child, struct pt_regs
 	return 0;
 }
 
-static void set_singlestep(struct task_struct *child)
+void user_enable_single_step(struct task_struct *child)
 {
 	struct pt_regs *regs = get_child_regs(child);
 
@@ -249,7 +249,7 @@ static void set_singlestep(struct task_struct *child)
 	child->ptrace |= PT_DTRACE;
 }
 
-static void clear_singlestep(struct task_struct *child)
+void user_disable_single_step(struct task_struct *child)
 {
 	/* Always clear TIF_SINGLESTEP... */
 	clear_tsk_thread_flag(child, TIF_SINGLESTEP);
@@ -269,7 +269,7 @@ static void clear_singlestep(struct task_struct *child)
  */
 void ptrace_disable(struct task_struct *child)
 { 
-	clear_singlestep(child);
+	user_disable_single_step(child);
 	clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
 }
 
@@ -403,7 +403,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
 		}
 		child->exit_code = data;
 		/* make sure the single step bit is not set. */
-		clear_singlestep(child);
+		user_disable_single_step(child);
 		wake_up_process(child);
 		ret = 0;
 		break;
@@ -419,7 +419,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
 			break;
 		child->exit_code = SIGKILL;
 		/* make sure the single step bit is not set. */
-		clear_singlestep(child);
+		user_disable_single_step(child);
 		wake_up_process(child);
 		break;
 
@@ -435,7 +435,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
 			clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
 
 		clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
-		set_singlestep(child);
+		user_enable_single_step(child);
 		child->exit_code = data;
 		/* give it a chance to run. */
 		wake_up_process(child);

arch/x86/kernel/ptrace_64.c

@@ -170,7 +170,7 @@ static int is_setting_trap_flag(struct task_struct *child, struct pt_regs *regs)
 	return 0;
 }
 
-static void set_singlestep(struct task_struct *child)
+void user_enable_single_step(struct task_struct *child)
 {
 	struct pt_regs *regs = task_pt_regs(child);
 
@@ -201,7 +201,7 @@ static void set_singlestep(struct task_struct *child)
 	child->ptrace |= PT_DTRACE;
 }
 
-static void clear_singlestep(struct task_struct *child)
+void user_disable_single_step(struct task_struct *child)
 {
 	/* Always clear TIF_SINGLESTEP... */
 	clear_tsk_thread_flag(child, TIF_SINGLESTEP);
@@ -221,7 +221,7 @@ static void clear_singlestep(struct task_struct *child)
  */
 void ptrace_disable(struct task_struct *child)
 { 
-	clear_singlestep(child);
+	user_disable_single_step(child);
 }
 
 static int putreg(struct task_struct *child,
@@ -461,7 +461,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
 		clear_tsk_thread_flag(child, TIF_SINGLESTEP);
 		child->exit_code = data;
 		/* make sure the single step bit is not set. */
-		clear_singlestep(child);
+		user_disable_single_step(child);
 		wake_up_process(child);
 		ret = 0;
 		break;
@@ -504,7 +504,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
 		clear_tsk_thread_flag(child, TIF_SINGLESTEP);
 		child->exit_code = SIGKILL;
 		/* make sure the single step bit is not set. */
-		clear_singlestep(child);
+		user_disable_single_step(child);
 		wake_up_process(child);
 		break;
 
@@ -513,7 +513,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
 		if (!valid_signal(data))
 			break;
 		clear_tsk_thread_flag(child,TIF_SYSCALL_TRACE);
-		set_singlestep(child);
+		user_enable_single_step(child);
 		child->exit_code = data;
 		/* give it a chance to run. */
 		wake_up_process(child);

include/asm-x86/ptrace.h

@@ -140,6 +140,13 @@ enum {
 
 #ifdef __KERNEL__
 
+/*
+ * These are defined as per linux/ptrace.h, which see.
+ */
+#define arch_has_single_step()	(1)
+extern void user_enable_single_step(struct task_struct *);
+extern void user_disable_single_step(struct task_struct *);
+
 struct user_desc;
 extern int do_get_thread_area(struct task_struct *p, int idx,
 			      struct user_desc __user *info);