fs: use kmem_cache_zalloc instead
[pv_ops_mirror.git] / include / asm-x86 / segment_32.h
blob597a47c2515f46a90acfffc987a0ad1bc5ff62a7
1 #ifndef _ASM_SEGMENT_H
2 #define _ASM_SEGMENT_H
4 /*
5 * The layout of the per-CPU GDT under Linux:
7 * 0 - null
8 * 1 - reserved
9 * 2 - reserved
10 * 3 - reserved
12 * 4 - unused <==== new cacheline
13 * 5 - unused
15 * ------- start of TLS (Thread-Local Storage) segments:
17 * 6 - TLS segment #1 [ glibc's TLS segment ]
18 * 7 - TLS segment #2 [ Wine's %fs Win32 segment ]
19 * 8 - TLS segment #3
20 * 9 - reserved
21 * 10 - reserved
22 * 11 - reserved
24 * ------- start of kernel segments:
26 * 12 - kernel code segment <==== new cacheline
27 * 13 - kernel data segment
28 * 14 - default user CS
29 * 15 - default user DS
30 * 16 - TSS
31 * 17 - LDT
32 * 18 - PNPBIOS support (16->32 gate)
33 * 19 - PNPBIOS support
34 * 20 - PNPBIOS support
35 * 21 - PNPBIOS support
36 * 22 - PNPBIOS support
37 * 23 - APM BIOS support
38 * 24 - APM BIOS support
39 * 25 - APM BIOS support
41 * 26 - ESPFIX small SS
42 * 27 - per-cpu [ offset to per-cpu data area ]
43 * 28 - unused
44 * 29 - unused
45 * 30 - unused
46 * 31 - TSS for double fault handler
48 #define GDT_ENTRY_TLS_ENTRIES 3
49 #define GDT_ENTRY_TLS_MIN 6
50 #define GDT_ENTRY_TLS_MAX (GDT_ENTRY_TLS_MIN + GDT_ENTRY_TLS_ENTRIES - 1)
52 #define TLS_SIZE (GDT_ENTRY_TLS_ENTRIES * 8)
54 #define GDT_ENTRY_DEFAULT_USER_CS 14
55 #define __USER_CS (GDT_ENTRY_DEFAULT_USER_CS * 8 + 3)
57 #define GDT_ENTRY_DEFAULT_USER_DS 15
58 #define __USER_DS (GDT_ENTRY_DEFAULT_USER_DS * 8 + 3)
60 #define GDT_ENTRY_KERNEL_BASE 12
62 #define GDT_ENTRY_KERNEL_CS (GDT_ENTRY_KERNEL_BASE + 0)
63 #define __KERNEL_CS (GDT_ENTRY_KERNEL_CS * 8)
65 #define GDT_ENTRY_KERNEL_DS (GDT_ENTRY_KERNEL_BASE + 1)
66 #define __KERNEL_DS (GDT_ENTRY_KERNEL_DS * 8)
68 #define GDT_ENTRY_TSS (GDT_ENTRY_KERNEL_BASE + 4)
69 #define GDT_ENTRY_LDT (GDT_ENTRY_KERNEL_BASE + 5)
71 #define GDT_ENTRY_PNPBIOS_BASE (GDT_ENTRY_KERNEL_BASE + 6)
72 #define GDT_ENTRY_APMBIOS_BASE (GDT_ENTRY_KERNEL_BASE + 11)
74 #define GDT_ENTRY_ESPFIX_SS (GDT_ENTRY_KERNEL_BASE + 14)
75 #define __ESPFIX_SS (GDT_ENTRY_ESPFIX_SS * 8)
77 #define GDT_ENTRY_PERCPU (GDT_ENTRY_KERNEL_BASE + 15)
78 #ifdef CONFIG_SMP
79 #define __KERNEL_PERCPU (GDT_ENTRY_PERCPU * 8)
80 #else
81 #define __KERNEL_PERCPU 0
82 #endif
84 #define GDT_ENTRY_DOUBLEFAULT_TSS 31
87 * The GDT has 32 entries
89 #define GDT_ENTRIES 32
90 #define GDT_SIZE (GDT_ENTRIES * 8)
92 /* Simple and small GDT entries for booting only */
94 #define GDT_ENTRY_BOOT_CS 2
95 #define __BOOT_CS (GDT_ENTRY_BOOT_CS * 8)
97 #define GDT_ENTRY_BOOT_DS (GDT_ENTRY_BOOT_CS + 1)
98 #define __BOOT_DS (GDT_ENTRY_BOOT_DS * 8)
100 /* The PnP BIOS entries in the GDT */
101 #define GDT_ENTRY_PNPBIOS_CS32 (GDT_ENTRY_PNPBIOS_BASE + 0)
102 #define GDT_ENTRY_PNPBIOS_CS16 (GDT_ENTRY_PNPBIOS_BASE + 1)
103 #define GDT_ENTRY_PNPBIOS_DS (GDT_ENTRY_PNPBIOS_BASE + 2)
104 #define GDT_ENTRY_PNPBIOS_TS1 (GDT_ENTRY_PNPBIOS_BASE + 3)
105 #define GDT_ENTRY_PNPBIOS_TS2 (GDT_ENTRY_PNPBIOS_BASE + 4)
107 /* The PnP BIOS selectors */
108 #define PNP_CS32 (GDT_ENTRY_PNPBIOS_CS32 * 8) /* segment for calling fn */
109 #define PNP_CS16 (GDT_ENTRY_PNPBIOS_CS16 * 8) /* code segment for BIOS */
110 #define PNP_DS (GDT_ENTRY_PNPBIOS_DS * 8) /* data segment for BIOS */
111 #define PNP_TS1 (GDT_ENTRY_PNPBIOS_TS1 * 8) /* transfer data segment */
112 #define PNP_TS2 (GDT_ENTRY_PNPBIOS_TS2 * 8) /* another data segment */
115 * The interrupt descriptor table has room for 256 idt's,
116 * the global descriptor table is dependent on the number
117 * of tasks we can have..
119 #define IDT_ENTRIES 256
121 /* Bottom two bits of selector give the ring privilege level */
122 #define SEGMENT_RPL_MASK 0x3
123 /* Bit 2 is table indicator (LDT/GDT) */
124 #define SEGMENT_TI_MASK 0x4
126 /* User mode is privilege level 3 */
127 #define USER_RPL 0x3
128 /* LDT segment has TI set, GDT has it cleared */
129 #define SEGMENT_LDT 0x4
130 #define SEGMENT_GDT 0x0
132 #ifndef CONFIG_PARAVIRT
133 #define get_kernel_rpl() 0
134 #endif
136 * Matching rules for certain types of segments.
139 /* Matches only __KERNEL_CS, ignoring PnP / USER / APM segments */
140 #define SEGMENT_IS_KERNEL_CODE(x) (((x) & 0xfc) == GDT_ENTRY_KERNEL_CS * 8)
142 /* Matches __KERNEL_CS and __USER_CS (they must be 2 entries apart) */
143 #define SEGMENT_IS_FLAT_CODE(x) (((x) & 0xec) == GDT_ENTRY_KERNEL_CS * 8)
145 /* Matches PNP_CS32 and PNP_CS16 (they must be consecutive) */
146 #define SEGMENT_IS_PNP_CODE(x) (((x) & 0xf4) == GDT_ENTRY_PNPBIOS_BASE * 8)
148 #endif