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/* Written 2000 by Andi Kleen */
#ifndef _ASM_X86_DESC_DEFS_H
#define _ASM_X86_DESC_DEFS_H
/*
* Segment descriptor structure definitions, usable from both x86_64 and i386
* archs.
*/
#ifndef __ASSEMBLY__
#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;
};
};
} __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), \
} } }
enum {
GATE_INTERRUPT = 0xE,
GATE_TRAP = 0xF,
GATE_CALL = 0xC,
GATE_TASK = 0x5,
};
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;
} __attribute__((packed));
#ifdef CONFIG_X86_64
typedef struct ldttss_desc64 ldt_desc;
typedef struct ldttss_desc64 tss_desc;
#else
typedef struct desc_struct ldt_desc;
typedef struct desc_struct tss_desc;
#endif
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
return g->offset_low | ((unsigned long)g->offset_middle << 16) |
((unsigned long) g->offset_high << 32);
#else
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;
unsigned long address;
} __attribute__((packed)) ;
#endif /* !__ASSEMBLY__ */
/* Access rights as returned by LAR */
#define AR_TYPE_RODATA (0 * (1 << 9))
#define AR_TYPE_RWDATA (1 * (1 << 9))
#define AR_TYPE_RODATA_EXPDOWN (2 * (1 << 9))
#define AR_TYPE_RWDATA_EXPDOWN (3 * (1 << 9))
#define AR_TYPE_XOCODE (4 * (1 << 9))
#define AR_TYPE_XRCODE (5 * (1 << 9))
#define AR_TYPE_XOCODE_CONF (6 * (1 << 9))
#define AR_TYPE_XRCODE_CONF (7 * (1 << 9))
#define AR_TYPE_MASK (7 * (1 << 9))
#define AR_DPL0 (0 * (1 << 13))
#define AR_DPL3 (3 * (1 << 13))
#define AR_DPL_MASK (3 * (1 << 13))
#define AR_A (1 << 8) /* "Accessed" */
#define AR_S (1 << 12) /* If clear, "System" segment */
#define AR_P (1 << 15) /* "Present" */
#define AR_AVL (1 << 20) /* "AVaiLable" (no HW effect) */
#define AR_L (1 << 21) /* "Long mode" for code segments */
#define AR_DB (1 << 22) /* D/B, effect depends on type */
#define AR_G (1 << 23) /* "Granularity" (limit in pages) */
#endif /* _ASM_X86_DESC_DEFS_H */
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