include/asm-um/ldt-x86_64.h

   1 /*
   2  * Copyright (C) 2004 Fujitsu Siemens Computers GmbH
   3  * Licensed under the GPL
   4  *
   5  * Author: Bodo Stroesser <bstroesser@fujitsu-siemens.com>
   6  */
   7
   8 #ifndef __ASM_LDT_X86_64_H
   9 #define __ASM_LDT_X86_64_H
  10
  11 #include "asm/semaphore.h"
  12 #include "asm/arch/ldt.h"
  13
  14 struct mmu_context_skas;
  15 extern void ldt_host_info(void);
  16 extern long init_new_ldt(struct mmu_context_skas * to_mm,
  17                          struct mmu_context_skas * from_mm);
  18 extern void free_ldt(struct mmu_context_skas * mm);
  19
  20 #define LDT_PAGES_MAX \
  21         ((LDT_ENTRIES * LDT_ENTRY_SIZE)/PAGE_SIZE)
  22 #define LDT_ENTRIES_PER_PAGE \
  23         (PAGE_SIZE/LDT_ENTRY_SIZE)
  24 #define LDT_DIRECT_ENTRIES \
  25         ((LDT_PAGES_MAX*sizeof(void *))/LDT_ENTRY_SIZE)
  26
  27 struct ldt_entry {
  28         __u32 a;
  29         __u32 b;
  30 };
  31
  32 typedef struct uml_ldt {
  33         int entry_count;
  34         struct semaphore semaphore;
  35         union {
  36                 struct ldt_entry * pages[LDT_PAGES_MAX];
  37                 struct ldt_entry entries[LDT_DIRECT_ENTRIES];
  38         } u;
  39 } uml_ldt_t;
  40
  41 /*
  42  * macros stolen from include/asm-x86_64/desc.h
  43  */
  44 #define LDT_entry_a(info) \
  45         ((((info)->base_addr & 0x0000ffff) << 16) | ((info)->limit & 0x0ffff))
  46
  47 /* Don't allow setting of the lm bit. It is useless anyways because
  48  * 64bit system calls require __USER_CS. */
  49 #define LDT_entry_b(info) \
  50         (((info)->base_addr & 0xff000000) | \
  51         (((info)->base_addr & 0x00ff0000) >> 16) | \
  52         ((info)->limit & 0xf0000) | \
  53         (((info)->read_exec_only ^ 1) << 9) | \
  54         ((info)->contents << 10) | \
  55         (((info)->seg_not_present ^ 1) << 15) | \
  56         ((info)->seg_32bit << 22) | \
  57         ((info)->limit_in_pages << 23) | \
  58         ((info)->useable << 20) | \
  59         /* ((info)->lm << 21) | */ \
  60         0x7000)
  61
  62 #define LDT_empty(info) (\
  63         (info)->base_addr       == 0    && \
  64         (info)->limit           == 0    && \
  65         (info)->contents        == 0    && \
  66         (info)->read_exec_only  == 1    && \
  67         (info)->seg_32bit       == 0    && \
  68         (info)->limit_in_pages  == 0    && \
  69         (info)->seg_not_present == 1    && \
  70         (info)->useable         == 0    && \
  71         (info)->lm              == 0)
  72
  73 #endif