1 files changed, 69 insertions, 0 deletions
diff --git a/kernel/include/asm/desc_defs.h b/kernel/include/asm/desc_defs.h
new file mode 100644
index 00000000..08900407
--- /dev/null
+++ b/kernel/include/asm/desc_defs.h
@@ -0,0 +1,69 @@
+/* Written 2000 by Andi Kleen */
+#ifndef __ARCH_DESC_DEFS_H
+#define __ARCH_DESC_DEFS_H
+
+/*
+ * Segment descriptor structure definitions, usable from both x86_64 and i386
+ * archs.
+ */
+
+#ifndef __ASSEMBLY__
+
+#include <linux/types.h>
+
+// 8 byte segment descriptor
+struct desc_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;
+} __attribute__((packed));
+
+struct n_desc_struct {
+	unsigned int a,b;
+};
+
+enum {
+	GATE_INTERRUPT = 0xE,
+	GATE_TRAP = 0xF,
+	GATE_CALL = 0xC,
+};
+
+// 16byte gate
+struct gate_struct {
+	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)(x) & 0xFFFF)
+#define PTR_MIDDLE(x) (((unsigned long)(x) >> 16) & 0xFFFF)
+#define PTR_HIGH(x) ((unsigned long)(x) >> 32)
+
+enum {
+	DESC_TSS = 0x9,
+	DESC_LDT = 0x2,
+};
+
+// LDT or TSS descriptor in the GDT. 16 bytes.
+struct ldttss_desc {
+	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;
+} __attribute__((packed));
+
+struct desc_ptr {
+	unsigned short size;
+	unsigned long address;
+} __attribute__((packed)) ;
+
+
+#endif /* !__ASSEMBLY__ */
+
+#endif