x86: x86-64 ia32 ptrace pt_regs cleanup

This cleans up the getreg32/putreg32 functions to use struct pt_regs in a
straightforward fashion, instead of equivalent ugly pointer arithmetic.

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

1 files changed, 9 insertions, 12 deletions

diff --git a/arch/x86/ia32/ptrace32.c b/arch/x86/ia32/ptrace32.c
index 1e382e3bd882..c52d0664c67f 100644
--- a/arch/x86/ia32/ptrace32.c
+++ b/arch/x86/ia32/ptrace32.c
@@ -37,11 +37,11 @@
 
 #define R32(l,q)                                                        \
         case offsetof(struct user32, regs.l):                           \
-                stack[offsetof(struct pt_regs, q) / 8] = val; break
+                regs->q = val; break;
 
 static int putreg32(struct task_struct *child, unsigned regno, u32 val)
 {
-        __u64 *stack = (__u64 *)task_pt_regs(child);
+        struct pt_regs *regs = task_pt_regs(child);
 
         switch (regno) {
         case offsetof(struct user32, regs.fs):
@@ -65,12 +65,12 @@ static int putreg32(struct task_struct *child, unsigned regno, u32 val)
         case offsetof(struct user32, regs.ss):
                 if ((val & 3) != 3)
                         return -EIO;
-                stack[offsetof(struct pt_regs, ss)/8] = val & 0xffff;
+                regs->ss = val & 0xffff;
                 break;
         case offsetof(struct user32, regs.cs):
                 if ((val & 3) != 3)
                         return -EIO;
-                stack[offsetof(struct pt_regs, cs)/8] = val & 0xffff;
+                regs->cs = val & 0xffff;
                 break;
 
         R32(ebx, bx);
@@ -84,9 +84,7 @@ static int putreg32(struct task_struct *child, unsigned regno, u32 val)
         R32(eip, ip);
         R32(esp, sp);
 
-        case offsetof(struct user32, regs.eflags): {
-                __u64 *flags = &stack[offsetof(struct pt_regs, flags)/8];
-
+        case offsetof(struct user32, regs.eflags):
                 val &= FLAG_MASK;
                 /*
                  * If the user value contains TF, mark that
@@ -97,9 +95,8 @@ static int putreg32(struct task_struct *child, unsigned regno, u32 val)
                         clear_tsk_thread_flag(child, TIF_FORCED_TF);
                 else if (test_tsk_thread_flag(child, TIF_FORCED_TF))
                         val |= X86_EFLAGS_TF;
-                *flags = val | (*flags & ~FLAG_MASK);
+                regs->flags = val | (regs->flags & ~FLAG_MASK);
                 break;
-        }
 
         case offsetof(struct user32, u_debugreg[0]) ...
                 offsetof(struct user32, u_debugreg[7]):
@@ -123,11 +120,11 @@ static int putreg32(struct task_struct *child, unsigned regno, u32 val)
 
 #define R32(l,q)                                                        \
         case offsetof(struct user32, regs.l):                           \
-                *val = stack[offsetof(struct pt_regs, q)/8]; break
+                *val = regs->q; break
 
 static int getreg32(struct task_struct *child, unsigned regno, u32 *val)
 {
-        __u64 *stack = (__u64 *)task_pt_regs(child);
+        struct pt_regs *regs = task_pt_regs(child);
 
         switch (regno) {
         case offsetof(struct user32, regs.fs):
@@ -160,7 +157,7 @@ static int getreg32(struct task_struct *child, unsigned regno, u32 *val)
                 /*
                  * If the debugger set TF, hide it from the readout.
                  */
-                *val = stack[offsetof(struct pt_regs, flags)/8];
+                *val = regs->flags;
                 if (test_tsk_thread_flag(child, TIF_FORCED_TF))
                         *val &= ~X86_EFLAGS_TF;
                 break;