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#ifndef _ASM_DESC_H_
#define _ASM_DESC_H_
#ifndef __ASSEMBLY__
#include <asm/desc_defs.h>
#include <asm/ldt.h>
#include <asm/mmu.h>
static inline void fill_ldt(struct desc_struct *desc, struct user_desc *info)
{
desc->limit0 = info->limit & 0x0ffff;
desc->base0 = info->base_addr & 0x0000ffff;
desc->base1 = (info->base_addr & 0x00ff0000) >> 16;
desc->type = (info->read_exec_only ^ 1) << 1;
desc->type |= info->contents << 2;
desc->s = 1;
desc->dpl = 0x3;
desc->p = info->seg_not_present ^ 1;
desc->limit = (info->limit & 0xf0000) >> 16;
desc->avl = info->useable;
desc->d = info->seg_32bit;
desc->g = info->limit_in_pages;
desc->base2 = (info->base_addr & 0xff000000) >> 24;
}
extern struct desc_ptr idt_descr;
extern gate_desc idt_table[];
#ifdef CONFIG_X86_32
# include "desc_32.h"
#else
# include "desc_64.h"
#endif
#define _LDT_empty(info) (\
(info)->base_addr == 0 && \
(info)->limit == 0 && \
(info)->contents == 0 && \
(info)->read_exec_only == 1 && \
(info)->seg_32bit == 0 && \
(info)->limit_in_pages == 0 && \
(info)->seg_not_present == 1 && \
(info)->useable == 0)
#ifdef CONFIG_X86_64
#define LDT_empty(info) (_LDT_empty(info) && ((info)->lm == 0))
#else
#define LDT_empty(info) (_LDT_empty(info))
#endif
static inline void clear_LDT(void)
{
set_ldt(NULL, 0);
}
/*
* load one particular LDT into the current CPU
*/
static inline void load_LDT_nolock(mm_context_t *pc)
{
set_ldt(pc->ldt, pc->size);
}
static inline void load_LDT(mm_context_t *pc)
{
preempt_disable();
load_LDT_nolock(pc);
preempt_enable();
}
static inline unsigned long get_desc_base(struct desc_struct *desc)
{
return desc->base0 | ((desc->base1) << 16) | ((desc->base2) << 24);
}
#else
/*
* GET_DESC_BASE reads the descriptor base of the specified segment.
*
* Args:
* idx - descriptor index
* gdt - GDT pointer
* base - 32bit register to which the base will be written
* lo_w - lo word of the "base" register
* lo_b - lo byte of the "base" register
* hi_b - hi byte of the low word of the "base" register
*
* Example:
* GET_DESC_BASE(GDT_ENTRY_ESPFIX_SS, %ebx, %eax, %ax, %al, %ah)
* Will read the base address of GDT_ENTRY_ESPFIX_SS and put it into %eax.
*/
#define GET_DESC_BASE(idx, gdt, base, lo_w, lo_b, hi_b) \
movb idx*8+4(gdt), lo_b; \
movb idx*8+7(gdt), hi_b; \
shll $16, base; \
movw idx*8+2(gdt), lo_w;
#endif /* __ASSEMBLY__ */
#endif
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