linux/arch/x86/include/asm/desc_defs.h
Thomas Gleixner 87cc037674 x86/ldttss: Clean up 32-bit descriptors
Like the IDT descriptors, the LDT/TSS descriptors are pointlessly different
on 32 and 64 bit kernels.

Unify them and get rid of the duplicated code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064958.289634692@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 12:07:25 +02:00

135 lines
3.1 KiB
C

/* 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>
/* 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 = (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,
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 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 */