[PATCH] sh: task_pt_regs()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/sh/kernel/process.c

@@ -191,13 +191,8 @@ void flush_thread(void)
 {
 #if defined(CONFIG_SH_FPU)
 	struct task_struct *tsk = current;
-	struct pt_regs *regs = (struct pt_regs *)
-				((unsigned long)tsk->thread_info
-				 + THREAD_SIZE - sizeof(struct pt_regs)
-				 - sizeof(unsigned long));
-
 	/* Forget lazy FPU state */
-	clear_fpu(tsk, regs);
+	clear_fpu(tsk, task_pt_regs(tsk));
 	clear_used_math();
 #endif
 }
@@ -232,13 +227,7 @@ int dump_task_regs(struct task_struct *tsk, elf_gregset_t *regs)
 {
 	struct pt_regs ptregs;
 	
-	ptregs = *(struct pt_regs *)
+	ptregs = *task_pt_regs(tsk);
-		((unsigned long)tsk->thread_info + THREAD_SIZE
-		 - sizeof(struct pt_regs)
-#ifdef CONFIG_SH_DSP
-		 - sizeof(struct pt_dspregs)
-#endif
-		 - sizeof(unsigned long));
 	elf_core_copy_regs(regs, &ptregs);
 
 	return 1;
@@ -252,11 +241,7 @@ dump_task_fpu (struct task_struct *tsk, elf_fpregset_t *fpu)
 #if defined(CONFIG_SH_FPU)
 	fpvalid = !!tsk_used_math(tsk);
 	if (fpvalid) {
-		struct pt_regs *regs = (struct pt_regs *)
+		unlazy_fpu(tsk, task_pt_regs(tsk));
-					((unsigned long)tsk->thread_info
-					 + THREAD_SIZE - sizeof(struct pt_regs)
-					 - sizeof(unsigned long));
-		unlazy_fpu(tsk, regs);
 		memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu));
 	}
 #endif
@@ -279,12 +264,7 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
 	copy_to_stopped_child_used_math(p);
 #endif
 
-	childregs = ((struct pt_regs *)
+	childregs = task_pt_regs(p);
-		(THREAD_SIZE + (unsigned long) p->thread_info)
-#ifdef CONFIG_SH_DSP
-		- sizeof(struct pt_dspregs)
-#endif
-		- sizeof(unsigned long)) - 1;
 	*childregs = *regs;
 
 	if (user_mode(regs)) {
@@ -333,11 +313,7 @@ ubc_set_tracing(int asid, unsigned long pc)
 struct task_struct *__switch_to(struct task_struct *prev, struct task_struct *next)
 {
 #if defined(CONFIG_SH_FPU)
-	struct pt_regs *regs = (struct pt_regs *)
+	unlazy_fpu(prev, task_pt_regs(prev));
-				((unsigned long)prev->thread_info
-				 + THREAD_SIZE - sizeof(struct pt_regs)
-				 - sizeof(unsigned long));
-	unlazy_fpu(prev, regs);
 #endif
 
 #ifdef CONFIG_PREEMPT
@@ -346,13 +322,7 @@ struct task_struct *__switch_to(struct task_struct *prev, struct task_struct *ne
 		struct pt_regs *regs;
 
 		local_irq_save(flags);
-		regs = (struct pt_regs *)
+		regs = task_pt_regs(prev);
-			((unsigned long)prev->thread_info
-			 + THREAD_SIZE - sizeof(struct pt_regs)
-#ifdef CONFIG_SH_DSP
-			 - sizeof(struct pt_dspregs)
-#endif
-			 - sizeof(unsigned long));
 		if (user_mode(regs) && regs->regs[15] >= 0xc0000000) {
 			int offset = (int)regs->regs[15];
 

arch/sh/kernel/ptrace.c

@@ -41,12 +41,7 @@ static inline int get_stack_long(struct task_struct *task, int offset)
 {
 	unsigned char *stack;
 
-	stack = (unsigned char *)
+	stack = (unsigned char *)task_pt_regs(task);
-		task->thread_info + THREAD_SIZE	- sizeof(struct pt_regs)
-#ifdef CONFIG_SH_DSP
-		- sizeof(struct pt_dspregs)
-#endif
-		- sizeof(unsigned long);
 	stack += offset;
 	return (*((int *)stack));
 }
@@ -59,12 +54,7 @@ static inline int put_stack_long(struct task_struct *task, int offset,
 {
 	unsigned char *stack;
 
-	stack = (unsigned char *)
+	stack = (unsigned char *)task_pt_regs(task);
-		task->thread_info + THREAD_SIZE - sizeof(struct pt_regs)
-#ifdef CONFIG_SH_DSP
-		- sizeof(struct pt_dspregs)
-#endif
-		- sizeof(unsigned long);
 	stack += offset;
 	*(unsigned long *) stack = data;
 	return 0;

include/asm-sh/ptrace.h

@@ -91,6 +91,16 @@ struct pt_dspregs {
 #define instruction_pointer(regs) ((regs)->pc)
 extern void show_regs(struct pt_regs *);
 
+#ifdef CONFIG_SH_DSP
+#define task_pt_regs(task) \
+	((struct pt_regs *) ((unsigned long)(task)->thread_info + THREAD_SIZE \
+		 - sizeof(struct pt_dspregs) - sizeof(unsigned long)) - 1)
+#else
+#define task_pt_regs(task) \
+	((struct pt_regs *) ((unsigned long)(task)->thread_info + THREAD_SIZE \
+		 - sizeof(unsigned long)) - 1)
+#endif
+
 static inline unsigned long profile_pc(struct pt_regs *regs)
 {
 	unsigned long pc = instruction_pointer(regs);