Linux Kernel  3.7.1
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ldt.h
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1 /*
2  * ldt.h
3  *
4  * Definitions of structures used with the modify_ldt system call.
5  */
6 #ifndef _ASM_X86_LDT_H
7 #define _ASM_X86_LDT_H
8 
9 /* Maximum number of LDT entries supported. */
10 #define LDT_ENTRIES 8192
11 /* The size of each LDT entry. */
12 #define LDT_ENTRY_SIZE 8
13 
14 #ifndef __ASSEMBLY__
15 /*
16  * Note on 64bit base and limit is ignored and you cannot set DS/ES/CS
17  * not to the default values if you still want to do syscalls. This
18  * call is more for 32bit mode therefore.
19  */
20 struct user_desc {
21  unsigned int entry_number;
22  unsigned int base_addr;
23  unsigned int limit;
24  unsigned int seg_32bit:1;
25  unsigned int contents:2;
26  unsigned int read_exec_only:1;
27  unsigned int limit_in_pages:1;
28  unsigned int seg_not_present:1;
29  unsigned int useable:1;
30 #ifdef __x86_64__
31  unsigned int lm:1;
32 #endif
33 };
34 
35 #define MODIFY_LDT_CONTENTS_DATA 0
36 #define MODIFY_LDT_CONTENTS_STACK 1
37 #define MODIFY_LDT_CONTENTS_CODE 2
38 
39 #endif /* !__ASSEMBLY__ */
40 #endif /* _ASM_X86_LDT_H */