1 files changed, 66 insertions, 56 deletions

diff --git a/arch/x86/include/asm/desc_defs.h b/arch/x86/include/asm/desc_defs.h
index 49265345d4d2..346d252029b7 100644
--- a/arch/x86/include/asm/desc_defs.h
+++ b/arch/x86/include/asm/desc_defs.h
@@ -11,34 +11,30 @@
 
 #include <linux/types.h>
 
-/*
- * FIXME: Accessing the desc_struct through its fields is more elegant,
- * and should be the one valid thing to do. However, a lot of open code
- * still touches the a and b accessors, and doing this allow us to do it
- * incrementally. We keep the signature as a struct, rather than a union,
- * so we can get rid of it transparently in the future -- glommer
- */
 /* 8 byte segment descriptor */
 struct desc_struct {
-	union {
-		struct {
-			unsigned int a;
-			unsigned int b;
-		};
-		struct {
-			u16 limit0;
-			u16 base0;
-			unsigned base1: 8, type: 4, s: 1, dpl: 2, p: 1;
-			unsigned limit: 4, avl: 1, l: 1, d: 1, g: 1, base2: 8;
-		};
-	};
+	u16	limit0;
+	u16	base0;
+	u16	base1: 8, type: 4, s: 1, dpl: 2, p: 1;
+	u16	limit1: 4, avl: 1, l: 1, d: 1, g: 1, base2: 8;
 } __attribute__((packed));
 
-#define GDT_ENTRY_INIT(flags, base, limit) { { { \
-		.a = ((limit) & 0xffff) | (((base) & 0xffff) << 16), \
-		.b = (((base) & 0xff0000) >> 16) | (((flags) & 0xf0ff) << 8) | \
-			((limit) & 0xf0000) | ((base) & 0xff000000), \
-	} } }
+#define GDT_ENTRY_INIT(flags, base, limit)			\
+	{							\
+		.limit0		= (u16) (limit),		\
+		.limit1		= ((limit) >> 16) & 0x0F,	\
+		.base0		= (u16) (base),			\
+		.base1		= ((base) >> 16) & 0xFF,	\
+		.base2		= ((base) >> 24) & 0xFF,	\
+		.type		= (flags & 0x0f),		\
+		.s		= (flags >> 4) & 0x01,		\
+		.dpl		= (flags >> 5) & 0x03,		\
+		.p		= (flags >> 7) & 0x01,		\
+		.avl		= (flags >> 12) & 0x01,		\
+		.l		= (flags >> 13) & 0x01,		\
+		.d		= (flags >> 14) & 0x01,		\
+		.g		= (flags >> 15) & 0x01,		\
+	}
 
 enum {
 	GATE_INTERRUPT = 0xE,
@@ -47,49 +43,63 @@ enum {
 	GATE_TASK = 0x5,
 };
 
-/* 16byte gate */
-struct gate_struct64 {
-	u16 offset_low;
-	u16 segment;
-	unsigned ist : 3, zero0 : 5, type : 5, dpl : 2, p : 1;
-	u16 offset_middle;
-	u32 offset_high;
-	u32 zero1;
-} __attribute__((packed));
-
-#define PTR_LOW(x) ((unsigned long long)(x) & 0xFFFF)
-#define PTR_MIDDLE(x) (((unsigned long long)(x) >> 16) & 0xFFFF)
-#define PTR_HIGH(x) ((unsigned long long)(x) >> 32)
-
 enum {
 	DESC_TSS = 0x9,
 	DESC_LDT = 0x2,
 	DESCTYPE_S = 0x10,	/* !system */
 };
 
-/* LDT or TSS descriptor in the GDT. 16 bytes. */
-struct ldttss_desc64 {
-	u16 limit0;
-	u16 base0;
-	unsigned base1 : 8, type : 5, dpl : 2, p : 1;
-	unsigned limit1 : 4, zero0 : 3, g : 1, base2 : 8;
-	u32 base3;
-	u32 zero1;
+/* LDT or TSS descriptor in the GDT. */
+struct ldttss_desc {
+	u16	limit0;
+	u16	base0;
+
+	u16	base1 : 8, type : 5, dpl : 2, p : 1;
+	u16	limit1 : 4, zero0 : 3, g : 1, base2 : 8;
+#ifdef CONFIG_X86_64
+	u32	base3;
+	u32	zero1;
+#endif
 } __attribute__((packed));
 
+typedef struct ldttss_desc ldt_desc;
+typedef struct ldttss_desc tss_desc;
+
+struct idt_bits {
+	u16		ist	: 3,
+			zero	: 5,
+			type	: 5,
+			dpl	: 2,
+			p	: 1;
+} __attribute__((packed));
+
+struct gate_struct {
+	u16		offset_low;
+	u16		segment;
+	struct idt_bits	bits;
+	u16		offset_middle;
+#ifdef CONFIG_X86_64
+	u32		offset_high;
+	u32		reserved;
+#endif
+} __attribute__((packed));
+
+typedef struct gate_struct gate_desc;
+
+static inline unsigned long gate_offset(const gate_desc *g)
+{
 #ifdef CONFIG_X86_64
-typedef struct gate_struct64 gate_desc;
-typedef struct ldttss_desc64 ldt_desc;
-typedef struct ldttss_desc64 tss_desc;
-#define gate_offset(g) ((g).offset_low | ((unsigned long)(g).offset_middle << 16) | ((unsigned long)(g).offset_high << 32))
-#define gate_segment(g) ((g).segment)
+	return g->offset_low | ((unsigned long)g->offset_middle << 16) |
+		((unsigned long) g->offset_high << 32);
 #else
-typedef struct desc_struct gate_desc;
-typedef struct desc_struct ldt_desc;
-typedef struct desc_struct tss_desc;
-#define gate_offset(g)		(((g).b & 0xffff0000) | ((g).a & 0x0000ffff))
-#define gate_segment(g)		((g).a >> 16)
+	return g->offset_low | ((unsigned long)g->offset_middle << 16);
 #endif
+}
+
+static inline unsigned long gate_segment(const gate_desc *g)
+{
+	return g->segment;
+}
 
 struct desc_ptr {
 	unsigned short size;