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/* SPDX-License-Identifier: GPL-2.0 */
/* 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.
*/
/*
* Low-level interface mapping flags/field names to bits
*/
/* Flags for _DESC_S (non-system) descriptors */
#define _DESC_ACCESSED 0x0001
#define _DESC_DATA_WRITABLE 0x0002
#define _DESC_CODE_READABLE 0x0002
#define _DESC_DATA_EXPAND_DOWN 0x0004
#define _DESC_CODE_CONFORMING 0x0004
#define _DESC_CODE_EXECUTABLE 0x0008
/* Common flags */
#define _DESC_S 0x0010
#define _DESC_DPL(dpl) ((dpl) << 5)
#define _DESC_PRESENT 0x0080
#define _DESC_LONG_CODE 0x2000
#define _DESC_DB 0x4000
#define _DESC_GRANULARITY_4K 0x8000
/* System descriptors have a numeric "type" field instead of flags */
#define _DESC_SYSTEM(code) (code)
/*
* High-level interface mapping intended usage to low-level combinations
* of flags
*/
#define _DESC_DATA (_DESC_S | _DESC_PRESENT | _DESC_ACCESSED | \
_DESC_DATA_WRITABLE)
#define _DESC_CODE (_DESC_S | _DESC_PRESENT | _DESC_ACCESSED | \
_DESC_CODE_READABLE | _DESC_CODE_EXECUTABLE)
#define DESC_DATA16 (_DESC_DATA)
#define DESC_CODE16 (_DESC_CODE)
#define DESC_DATA32 (_DESC_DATA | _DESC_GRANULARITY_4K | _DESC_DB)
#define DESC_DATA32_BIOS (_DESC_DATA | _DESC_DB)
#define DESC_CODE32 (_DESC_CODE | _DESC_GRANULARITY_4K | _DESC_DB)
#define DESC_CODE32_BIOS (_DESC_CODE | _DESC_DB)
#define DESC_TSS32 (_DESC_SYSTEM(9) | _DESC_PRESENT)
#define DESC_DATA64 (_DESC_DATA | _DESC_GRANULARITY_4K | _DESC_DB)
#define DESC_CODE64 (_DESC_CODE | _DESC_GRANULARITY_4K | _DESC_LONG_CODE)
#define DESC_USER (_DESC_DPL(3))
#ifndef __ASSEMBLY__
#include <linux/types.h>
/* 8 byte segment descriptor */
struct desc_struct {
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) \
{ \
.limit0 = ((limit) >> 0) & 0xFFFF, \
.limit1 = ((limit) >> 16) & 0x000F, \
.base0 = ((base) >> 0) & 0xFFFF, \
.base1 = ((base) >> 16) & 0x00FF, \
.base2 = ((base) >> 24) & 0x00FF, \
.type = ((flags) >> 0) & 0x000F, \
.s = ((flags) >> 4) & 0x0001, \
.dpl = ((flags) >> 5) & 0x0003, \
.p = ((flags) >> 7) & 0x0001, \
.avl = ((flags) >> 12) & 0x0001, \
.l = ((flags) >> 13) & 0x0001, \
.d = ((flags) >> 14) & 0x0001, \
.g = ((flags) >> 15) & 0x0001, \
}
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. */
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 idt_data {
unsigned int vector;
unsigned int segment;
struct idt_bits bits;
const void *addr;
};
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;
#ifndef _SETUP
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;
}
#endif
struct desc_ptr {
unsigned short size;
unsigned long address;
} __attribute__((packed)) ;
#endif /* !__ASSEMBLY__ */
/* Boot IDT definitions */
#define BOOT_IDT_ENTRIES 32
/* 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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