x86: use regparm(3) for passed-in pt_regs pointer

[deliverable/linux.git] / arch / x86 / kernel / signal.c

diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c
index 7fc78b0198150f72fa4185a9c7f365a488f72a04..ccfb27412f0f817636beaffe044bc4b8166a2ba9 100644 (file)
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -50,27 +50,23 @@
 # define FIX_EFLAGS    __FIX_EFLAGS
 #endif
 
-#define COPY(x)                        {               \
-       get_user_ex(regs->x, &sc->x);           \
-}
+#define COPY(x)                        do {                    \
+       get_user_ex(regs->x, &sc->x);                   \
+} while (0)
 
-#define COPY_SEG(seg)          {                       \
-               unsigned short tmp;                     \
-               get_user_ex(tmp, &sc->seg);             \
-               regs->seg = tmp;                        \
-}
+#define GET_SEG(seg)           ({                      \
+       unsigned short tmp;                             \
+       get_user_ex(tmp, &sc->seg);                     \
+       tmp;                                            \
+})
 
-#define COPY_SEG_CPL3(seg)     {                       \
-               unsigned short tmp;                     \
-               get_user_ex(tmp, &sc->seg);             \
-               regs->seg = tmp | 3;                    \
-}
+#define COPY_SEG(seg)          do {                    \
+       regs->seg = GET_SEG(seg);                       \
+} while (0)
 
-#define GET_SEG(seg)           {                       \
-               unsigned short tmp;                     \
-               get_user_ex(tmp, &sc->seg);             \
-               loadsegment(seg, tmp);                  \
-}
+#define COPY_SEG_CPL3(seg)     do {                    \
+       regs->seg = GET_SEG(seg) | 3;                   \
+} while (0)
 
 static int
 restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc,
@@ -86,7 +82,7 @@ restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc,
        get_user_try {
 
 #ifdef CONFIG_X86_32
-               GET_SEG(gs);
+               set_user_gs(regs, GET_SEG(gs));
                COPY_SEG(fs);
                COPY_SEG(es);
                COPY_SEG(ds);
@@ -138,12 +134,7 @@ setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate,
        put_user_try {
 
 #ifdef CONFIG_X86_32
-               {
-                       unsigned int tmp;
-
-                       savesegment(gs, tmp);
-                       put_user_ex(tmp, (unsigned int __user *)&sc->gs);
-               }
+               put_user_ex(get_user_gs(regs), (unsigned int __user *)&sc->gs);
                put_user_ex(regs->fs, (unsigned int __user *)&sc->fs);
                put_user_ex(regs->es, (unsigned int __user *)&sc->es);
                put_user_ex(regs->ds, (unsigned int __user *)&sc->ds);
@@ -558,14 +549,9 @@ sys_sigaction(int sig, const struct old_sigaction __user *act,
 #endif /* CONFIG_X86_32 */
 
 #ifdef CONFIG_X86_32
-asmlinkage int sys_sigaltstack(unsigned long bx)
+int sys_sigaltstack(struct pt_regs *regs)
 {
-       /*
-        * This is needed to make gcc realize it doesn't own the
-        * "struct pt_regs"
-        */
-       struct pt_regs *regs = (struct pt_regs *)&bx;
-       const stack_t __user *uss = (const stack_t __user *)bx;
+       const stack_t __user *uss = (const stack_t __user *)regs->bx;
        stack_t __user *uoss = (stack_t __user *)regs->cx;
 
        return do_sigaltstack(uss, uoss, regs->sp);
@@ -583,14 +569,12 @@ sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
  * Do a signal return; undo the signal stack.
  */
 #ifdef CONFIG_X86_32
-asmlinkage unsigned long sys_sigreturn(unsigned long __unused)
+unsigned long sys_sigreturn(struct pt_regs *regs)
 {
        struct sigframe __user *frame;
-       struct pt_regs *regs;
        unsigned long ax;
        sigset_t set;
 
-       regs = (struct pt_regs *) &__unused;
        frame = (struct sigframe __user *)(regs->sp - 8);
 
        if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
@@ -649,15 +633,8 @@ badframe:
 }
 
 #ifdef CONFIG_X86_32
-/*
- * Note: do not pass in pt_regs directly as with tail-call optimization
- * GCC will incorrectly stomp on the caller's frame and corrupt user-space
- * register state:
- */
-asmlinkage int sys_rt_sigreturn(unsigned long __unused)
+int sys_rt_sigreturn(struct pt_regs *regs)
 {
-       struct pt_regs *regs = (struct pt_regs *)&__unused;
-
        return do_rt_sigreturn(regs);
 }
 #else /* !CONFIG_X86_32 */