x86: change write_ldt_entry signature

this patch changes the signature of write_ldt_entry.
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>

arch/x86/kernel/ldt.c

@@ -229,8 +229,7 @@ static int write_ldt(void __user *ptr, unsigned long bytecount, int oldmode)
 
 	/* Install the new entry ...  */
 install:
-	write_ldt_entry(mm->context.ldt, ldt_info.entry_number,
-			ldt.a, ldt.b);
+	write_ldt_entry(mm->context.ldt, ldt_info.entry_number, &ldt);
 	error = 0;
 
 out_unlock:

arch/x86/kernel/paravirt_32.c

@@ -379,7 +379,7 @@ struct pv_cpu_ops pv_cpu_ops = {
 	.store_idt = native_store_idt,
 	.store_tr = native_store_tr,
 	.load_tls = native_load_tls,
-	.write_ldt_entry = write_dt_entry,
+	.write_ldt_entry = native_write_ldt_entry,
 	.write_gdt_entry = native_write_gdt_entry,
 	.write_idt_entry = native_write_idt_entry,
 	.load_sp0 = native_load_sp0,

arch/x86/kernel/vmi_32.c

@@ -64,6 +64,7 @@ static struct {
 	void (*set_tr)(u32 selector);
 	void (*write_idt_entry)(struct desc_struct *, int, u32, u32);
 	void (*write_gdt_entry)(struct desc_struct *, int, u32, u32);
+	void (*write_ldt_entry)(struct desc_struct *, int, u32, u32);
 	void (*set_kernel_stack)(u32 selector, u32 sp0);
 	void (*allocate_page)(u32, u32, u32, u32, u32);
 	void (*release_page)(u32, u32);
@@ -229,6 +230,13 @@ static void vmi_write_gdt_entry(struct desc_struct *dt, int entry,
 	vmi_ops.write_gdt_entry(dt, entry, gdt_entry[0], gdt_entry[2]);
 }
 
+static void vmi_write_ldt_entry(struct desc_struct *dt, int entry,
+				const void *desc)
+{
+	u32 *ldt_entry = (u32 *)desc;
+	vmi_ops.write_idt_entry(dt, entry, ldt_entry[0], ldt_entry[2]);
+}
+
 static void vmi_load_sp0(struct tss_struct *tss,
 				   struct thread_struct *thread)
 {
@@ -805,7 +813,8 @@ static inline int __init activate_vmi(void)
 	para_fill(pv_cpu_ops.store_idt, GetIDT);
 	para_fill(pv_cpu_ops.store_tr, GetTR);
 	pv_cpu_ops.load_tls = vmi_load_tls;
-	para_fill(pv_cpu_ops.write_ldt_entry, WriteLDTEntry);
+	para_wrap(pv_cpu_ops.write_ldt_entry, vmi_write_ldt_entry,
+		  write_ldt_entry, WriteLDTEntry);
 	para_wrap(pv_cpu_ops.write_gdt_entry, vmi_write_gdt_entry,
 		  write_gdt_entry, WriteGDTEntry);
 	para_wrap(pv_cpu_ops.write_idt_entry, vmi_write_idt_entry,

arch/x86/xen/enlighten.c

@@ -357,11 +357,11 @@ static void xen_load_tls(struct thread_struct *t, unsigned int cpu)
 }
 
 static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum,
-				u32 low, u32 high)
+				const void *ptr)
 {
 	unsigned long lp = (unsigned long)&dt[entrynum];
 	xmaddr_t mach_lp = virt_to_machine(lp);
-	u64 entry = (u64)high << 32 | low;
+	u64 entry = *(u64 *)ptr;
 
 	preempt_disable();
 

include/asm-x86/desc_32.h

@@ -69,12 +69,19 @@ static inline void pack_gate(gate_desc *gate,
 #define load_TLS(t, cpu) native_load_tls(t, cpu)
 #define set_ldt native_set_ldt
 
-#define write_ldt_entry(dt, entry, a, b) write_dt_entry(dt, entry, a, b)
+#define write_ldt_entry(dt, entry, desc) \
+				native_write_ldt_entry(dt, entry, desc)
 #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
 
+static inline void native_write_ldt_entry(struct desc_struct *ldt, int entry,
+					  const void *desc)
+{
+	memcpy(&ldt[entry], desc, sizeof(struct desc_struct));
+}
+
 static inline void native_write_idt_entry(gate_desc *idt, int entry,
 					  const gate_desc *gate)
 {

include/asm-x86/desc_64.h

@@ -34,12 +34,9 @@ extern gate_desc idt_table[];
 extern struct desc_ptr cpu_gdt_descr[];
 
 static inline void write_ldt_entry(struct desc_struct *ldt,
-				   int entry, u32 entry_low, u32 entry_high)
+				   int entry, void *ptr)
 {
-	__u32 *lp = (__u32 *)((entry << 3) + (char *)ldt);
-
-	lp[0] = entry_low;
-	lp[1] = entry_high;
+	memcpy(&ldt[entry], ptr, 8);
 }
 
 /* the cpu gdt accessor */

include/asm-x86/paravirt.h

@@ -96,8 +96,8 @@ struct pv_cpu_ops {
 	void (*set_ldt)(const void *desc, unsigned entries);
 	unsigned long (*store_tr)(void);
 	void (*load_tls)(struct thread_struct *t, unsigned int cpu);
-	void (*write_ldt_entry)(struct desc_struct *,
-				int entrynum, u32 low, u32 high);
+	void (*write_ldt_entry)(struct desc_struct *ldt, int entrynum,
+				const void *desc);
 	void (*write_gdt_entry)(struct desc_struct *,
 				int entrynum, const void *desc, int size);
 	void (*write_idt_entry)(gate_desc *,
@@ -660,9 +660,11 @@ static inline void load_TLS(struct thread_struct *t, unsigned cpu)
 {
 	PVOP_VCALL2(pv_cpu_ops.load_tls, t, cpu);
 }
-static inline void write_ldt_entry(void *dt, int entry, u32 low, u32 high)
+
+static inline void write_ldt_entry(struct desc_struct *dt, int entry,
+				   const void *desc)
 {
-	PVOP_VCALL4(pv_cpu_ops.write_ldt_entry, dt, entry, low, high);
+	PVOP_VCALL3(pv_cpu_ops.write_ldt_entry, dt, entry, desc);
 }
 
 static inline void write_gdt_entry(struct desc_struct *dt, int entry,