x86: unify struct desc_ptr

This patch unifies struct desc_ptr between i386 and x86_64.
They can be expressed in the exact same way in C code, only
having to change the name of one of them. As Xgt_desc_struct
is ugly and big, this is the one that goes away.

There's also a padding field in i386, but it is not really
needed in the C structure definition.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index d81e8d7..c32e0fd 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -295,7 +295,7 @@
 	xen_mc_issue(PARAVIRT_LAZY_CPU);
 }
 
-static void xen_load_gdt(const struct Xgt_desc_struct *dtr)
+static void xen_load_gdt(const struct desc_ptr *dtr)
 {
 	unsigned long *frames;
 	unsigned long va = dtr->address;
@@ -395,7 +395,7 @@
 }
 
 /* Locations of each CPU's IDT */
-static DEFINE_PER_CPU(struct Xgt_desc_struct, idt_desc);
+static DEFINE_PER_CPU(struct desc_ptr, idt_desc);
 
 /* Set an IDT entry.  If the entry is part of the current IDT, then
    also update Xen. */
@@ -427,7 +427,7 @@
 	preempt_enable();
 }
 
-static void xen_convert_trap_info(const struct Xgt_desc_struct *desc,
+static void xen_convert_trap_info(const struct desc_ptr *desc,
 				  struct trap_info *traps)
 {
 	unsigned in, out, count;
@@ -446,7 +446,7 @@
 
 void xen_copy_trap_info(struct trap_info *traps)
 {
-	const struct Xgt_desc_struct *desc = &__get_cpu_var(idt_desc);
+	const struct desc_ptr *desc = &__get_cpu_var(idt_desc);
 
 	xen_convert_trap_info(desc, traps);
 }
@@ -454,7 +454,7 @@
 /* Load a new IDT into Xen.  In principle this can be per-CPU, so we
    hold a spinlock to protect the static traps[] array (static because
    it avoids allocation, and saves stack space). */
-static void xen_load_idt(const struct Xgt_desc_struct *desc)
+static void xen_load_idt(const struct desc_ptr *desc)
 {
 	static DEFINE_SPINLOCK(lock);
 	static struct trap_info traps[257];