x86: change write_gdt_entry signature.

This patch changes the write_gdt_entry function signature.
Instead of the old "a" and "b" parameters, it now receives
a pointer to a desc_struct, and the size of the entry being
handled. This is because x86_64 can have some 16-byte entries
as well as 8-byte ones.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
CC: Zachary Amsden <zach@vmware.com>
CC: Jeremy Fitzhardinge <Jeremy.Fitzhardinge.citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

2 files changed, 28 insertions, 15 deletions

diff --git a/include/asm-x86/desc_32.h b/include/asm-x86/desc_32.h
index 0370099..41d8214 100644
--- a/include/asm-x86/desc_32.h
+++ b/include/asm-x86/desc_32.h
@@ -28,12 +28,13 @@ extern struct desc_ptr idt_descr;
 extern gate_desc idt_table[];
 extern void set_intr_gate(unsigned int irq, void * addr);
 
-static inline void pack_descriptor(__u32 *a, __u32 *b,
+static inline void pack_descriptor(struct desc_struct *desc,
 	unsigned long base, unsigned long limit, unsigned char type, unsigned char flags)
 {
-	*a = ((base & 0xffff) << 16) | (limit & 0xffff);
-	*b = (base & 0xff000000) | ((base & 0xff0000) >> 16) |
+	desc->a = ((base & 0xffff) << 16) | (limit & 0xffff);
+	desc->b = (base & 0xff000000) | ((base & 0xff0000) >> 16) |
 		(limit & 0x000f0000) | ((type & 0xff) << 8) | ((flags & 0xf) << 20);
+	desc->p = 1;
 }
 
 static inline void pack_gate(gate_desc *gate,
@@ -69,7 +70,8 @@ static inline void pack_gate(gate_desc *gate,
 #define set_ldt native_set_ldt
 
 #define write_ldt_entry(dt, entry, a, b) write_dt_entry(dt, entry, a, b)
-#define write_gdt_entry(dt, entry, a, b) write_dt_entry(dt, entry, a, b)
+#define write_gdt_entry(dt, entry, desc, type) \
+				native_write_gdt_entry(dt, entry, desc, type)
 #define write_idt_entry(dt, entry, g) native_write_idt_entry(dt, entry, g)
 #endif
 
@@ -79,6 +81,12 @@ static inline void native_write_idt_entry(gate_desc *idt, int entry,
 	memcpy(&idt[entry], gate, sizeof(*gate));
 }
 
+static inline void native_write_gdt_entry(struct desc_struct *gdt, int entry,
+					  const void *desc, int type)
+{
+	memcpy(&gdt[entry], desc, sizeof(struct desc_struct));
+}
+
 static inline void write_dt_entry(struct desc_struct *dt,
 				  int entry, u32 entry_low, u32 entry_high)
 {
@@ -86,18 +94,20 @@ static inline void write_dt_entry(struct desc_struct *dt,
 	dt[entry].b = entry_high;
 }
 
+
 static inline void native_set_ldt(const void *addr, unsigned int entries)
 {
 	if (likely(entries == 0))
 		__asm__ __volatile__("lldt %w0"::"q" (0));
 	else {
 		unsigned cpu = smp_processor_id();
-		__u32 a, b;
+		ldt_desc ldt;
 
-		pack_descriptor(&a, &b, (unsigned long)addr,
+		pack_descriptor(&ldt, (unsigned long)addr,
 				entries * sizeof(struct desc_struct) - 1,
-				DESCTYPE_LDT, 0);
-		write_gdt_entry(get_cpu_gdt_table(cpu), GDT_ENTRY_LDT, a, b);
+				DESC_LDT, 0);
+		write_gdt_entry(get_cpu_gdt_table(cpu), GDT_ENTRY_LDT,
+				&ldt, DESC_LDT);
 		__asm__ __volatile__("lldt %w0"::"q" (GDT_ENTRY_LDT*8));
 	}
 }
@@ -153,11 +163,11 @@ static inline void _set_gate(int gate, unsigned int type, void *addr, unsigned s
 
 static inline void __set_tss_desc(unsigned int cpu, unsigned int entry, const void *addr)
 {
-	__u32 a, b;
-	pack_descriptor(&a, &b, (unsigned long)addr,
+	tss_desc tss;
+	pack_descriptor(&tss, (unsigned long)addr,
 			offsetof(struct tss_struct, __cacheline_filler) - 1,
-			DESCTYPE_TSS, 0);
-	write_gdt_entry(get_cpu_gdt_table(cpu), entry, a, b);
+			DESC_TSS, 0);
+	write_gdt_entry(get_cpu_gdt_table(cpu), entry, &tss, DESC_TSS);
 }
 
 
diff --git a/include/asm-x86/paravirt.h b/include/asm-x86/paravirt.h
index 86a9d7b..3f2abf2 100644
--- a/include/asm-x86/paravirt.h
+++ b/include/asm-x86/paravirt.h
@@ -99,7 +99,7 @@ struct pv_cpu_ops {
 	void (*write_ldt_entry)(struct desc_struct *,
 				int entrynum, u32 low, u32 high);
 	void (*write_gdt_entry)(struct desc_struct *,
-				int entrynum, u32 low, u32 high);
+				int entrynum, const void *desc, int size);
 	void (*write_idt_entry)(gate_desc *,
 				int entrynum, const gate_desc *gate);
 	void (*load_sp0)(struct tss_struct *tss, struct thread_struct *t);
@@ -664,10 +664,13 @@ static inline void write_ldt_entry(void *dt, int entry, u32 low, u32 high)
 {
 	PVOP_VCALL4(pv_cpu_ops.write_ldt_entry, dt, entry, low, high);
 }
-static inline void write_gdt_entry(void *dt, int entry, u32 low, u32 high)
+
+static inline void write_gdt_entry(struct desc_struct *dt, int entry,
+				   void *desc, int type)
 {
-	PVOP_VCALL4(pv_cpu_ops.write_gdt_entry, dt, entry, low, high);
+	PVOP_VCALL4(pv_cpu_ops.write_gdt_entry, dt, entry, desc, type);
 }
+
 static inline void write_idt_entry(gate_desc *dt, int entry, const gate_desc *g)
 {
 	PVOP_VCALL3(pv_cpu_ops.write_idt_entry, dt, entry, g);