ptrace: cleanup arch_ptrace() on sh

Remove unnecessary castings and get rid of dummy pointer in favor of
offsetof() macro in ptrace_32.c. Also use temporary variables and
break long lines in order to improve readability.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 33 insertions, 24 deletions

diff --git a/arch/sh/kernel/ptrace_32.c b/arch/sh/kernel/ptrace_32.c
index 34bf03745e8..90a15d29fee 100644
--- a/arch/sh/kernel/ptrace_32.c
+++ b/arch/sh/kernel/ptrace_32.c
@@ -368,7 +368,6 @@ const struct user_regset_view *task_user_regset_view(struct task_struct *task)
 long arch_ptrace(struct task_struct *child, long request,
                  unsigned long addr, unsigned long data)
 {
-        struct user * dummy = NULL;
         unsigned long __user *datap = (unsigned long __user *)data;
         int ret;
 
@@ -384,17 +383,20 @@ long arch_ptrace(struct task_struct *child, long request,
 
                 if (addr < sizeof(struct pt_regs))
                         tmp = get_stack_long(child, addr);
-                else if (addr >= (unsigned long) &dummy->fpu &&
-                         addr < (unsigned long) &dummy->u_fpvalid) {
+                else if (addr >= offsetof(struct user, fpu) &&
+                         addr < offsetof(struct user, u_fpvalid)) {
                         if (!tsk_used_math(child)) {
-                                if (addr == (unsigned long)&dummy->fpu.fpscr)
+                                if (addr == offsetof(struct user, fpu.fpscr))
                                         tmp = FPSCR_INIT;
                                 else
                                         tmp = 0;
-                        } else
+                        } else {
+                                unsigned long index;
+                                index = addr - offsetof(struct user, fpu);
                                 tmp = ((unsigned long *)child->thread.xstate)
-                                        [(addr - (long)&dummy->fpu) >> 2];
-                } else if (addr == (unsigned long) &dummy->u_fpvalid)
+                                        [index >> 2];
+                        }
+                } else if (addr == offsetof(struct user, u_fpvalid))
                         tmp = !!tsk_used_math(child);
                 else if (addr == PT_TEXT_ADDR)
                         tmp = child->mm->start_code;
@@ -418,13 +420,15 @@ long arch_ptrace(struct task_struct *child, long request,
 
                 if (addr < sizeof(struct pt_regs))
                         ret = put_stack_long(child, addr, data);
-                else if (addr >= (unsigned long) &dummy->fpu &&
-                         addr < (unsigned long) &dummy->u_fpvalid) {
+                else if (addr >= offsetof(struct user, fpu) &&
+                         addr < offsetof(struct user, u_fpvalid)) {
+                        unsigned long index;
+                        index = addr - offsetof(struct user, fpu);
                         set_stopped_child_used_math(child);
                         ((unsigned long *)child->thread.xstate)
-                                [(addr - (long)&dummy->fpu) >> 2] = data;
+                                [index >> 2] = data;
                         ret = 0;
-                } else if (addr == (unsigned long) &dummy->u_fpvalid) {
+                } else if (addr == offsetof(struct user, u_fpvalid)) {
                         conditional_stopped_child_used_math(data, child);
                         ret = 0;
                 }
@@ -434,35 +438,35 @@ long arch_ptrace(struct task_struct *child, long request,
                 return copy_regset_to_user(child, &user_sh_native_view,
                                            REGSET_GENERAL,
                                            0, sizeof(struct pt_regs),
-                                           (void __user *)data);
+                                           datap);
         case PTRACE_SETREGS:
                 return copy_regset_from_user(child, &user_sh_native_view,
                                              REGSET_GENERAL,
                                              0, sizeof(struct pt_regs),
-                                             (const void __user *)data);
+                                             datap);
 #ifdef CONFIG_SH_FPU
         case PTRACE_GETFPREGS:
                 return copy_regset_to_user(child, &user_sh_native_view,
                                            REGSET_FPU,
                                            0, sizeof(struct user_fpu_struct),
-                                           (void __user *)data);
+                                           datap);
         case PTRACE_SETFPREGS:
                 return copy_regset_from_user(child, &user_sh_native_view,
                                              REGSET_FPU,
                                              0, sizeof(struct user_fpu_struct),
-                                             (const void __user *)data);
+                                             datap);
 #endif
 #ifdef CONFIG_SH_DSP
         case PTRACE_GETDSPREGS:
                 return copy_regset_to_user(child, &user_sh_native_view,
                                            REGSET_DSP,
                                            0, sizeof(struct pt_dspregs),
-                                           (void __user *)data);
+                                           datap);
         case PTRACE_SETDSPREGS:
                 return copy_regset_from_user(child, &user_sh_native_view,
                                              REGSET_DSP,
                                              0, sizeof(struct pt_dspregs),
-                                             (const void __user *)data);
+                                             datap);
 #endif
         default:
                 ret = ptrace_request(child, request, addr, data);
diff --git a/arch/sh/kernel/ptrace_64.c b/arch/sh/kernel/ptrace_64.c
index 4840716c196..4436eacddb1 100644
--- a/arch/sh/kernel/ptrace_64.c
+++ b/arch/sh/kernel/ptrace_64.c
@@ -387,6 +387,7 @@ long arch_ptrace(struct task_struct *child, long request,
                  unsigned long addr, unsigned long data)
 {
         int ret;
+        unsigned long __user *datap = (unsigned long __user *) data;
 
         switch (request) {
         /* read the word at location addr in the USER area. */
@@ -401,13 +402,15 @@ long arch_ptrace(struct task_struct *child, long request,
                         tmp = get_stack_long(child, addr);
                 else if ((addr >= offsetof(struct user, fpu)) &&
                          (addr <  offsetof(struct user, u_fpvalid))) {
-                        tmp = get_fpu_long(child, addr - offsetof(struct user, fpu));
+                        unsigned long index;
+                        index = addr - offsetof(struct user, fpu);
+                        tmp = get_fpu_long(child, index);
                 } else if (addr == offsetof(struct user, u_fpvalid)) {
                         tmp = !!tsk_used_math(child);
                 } else {
                         break;
                 }
-                ret = put_user(tmp, (unsigned long *)data);
+                ret = put_user(tmp, datap);
                 break;
         }
 
@@ -438,7 +441,9 @@ long arch_ptrace(struct task_struct *child, long request,
                 }
                 else if ((addr >= offsetof(struct user, fpu)) &&
                          (addr <  offsetof(struct user, u_fpvalid))) {
-                        ret = put_fpu_long(child, addr - offsetof(struct user, fpu), data);
+                        unsigned long index;
+                        index = addr - offsetof(struct user, fpu);
+                        ret = put_fpu_long(child, index, data);
                 }
                 break;
 
@@ -446,23 +451,23 @@ long arch_ptrace(struct task_struct *child, long request,
                 return copy_regset_to_user(child, &user_sh64_native_view,
                                            REGSET_GENERAL,
                                            0, sizeof(struct pt_regs),
-                                           (void __user *)data);
+                                           datap);
         case PTRACE_SETREGS:
                 return copy_regset_from_user(child, &user_sh64_native_view,
                                              REGSET_GENERAL,
                                              0, sizeof(struct pt_regs),
-                                             (const void __user *)data);
+                                             datap);
 #ifdef CONFIG_SH_FPU
         case PTRACE_GETFPREGS:
                 return copy_regset_to_user(child, &user_sh64_native_view,
                                            REGSET_FPU,
                                            0, sizeof(struct user_fpu_struct),
-                                           (void __user *)data);
+                                           datap);
         case PTRACE_SETFPREGS:
                 return copy_regset_from_user(child, &user_sh64_native_view,
                                              REGSET_FPU,
                                              0, sizeof(struct user_fpu_struct),
-                                             (const void __user *)data);
+                                             datap);
 #endif
         default:
                 ret = ptrace_request(child, request, addr, data);