segment.h 5.88 KB
Newer Older
1 2
#ifndef ASM_X86__SEGMENT_H
#define ASM_X86__SEGMENT_H
3

4 5 6 7 8 9 10 11 12
/* Constructor for a conventional segment GDT (or LDT) entry */
/* This is a macro so it can be used in initializers */
#define GDT_ENTRY(flags, base, limit)			\
	((((base)  & 0xff000000ULL) << (56-24)) |	\
	 (((flags) & 0x0000f0ffULL) << 40) |		\
	 (((limit) & 0x000f0000ULL) << (48-16)) |	\
	 (((base)  & 0x00ffffffULL) << 16) |		\
	 (((limit) & 0x0000ffffULL)))

13 14 15 16 17 18 19 20
/* Simple and small GDT entries for booting only */

#define GDT_ENTRY_BOOT_CS	2
#define __BOOT_CS		(GDT_ENTRY_BOOT_CS * 8)

#define GDT_ENTRY_BOOT_DS	(GDT_ENTRY_BOOT_CS + 1)
#define __BOOT_DS		(GDT_ENTRY_BOOT_DS * 8)

21 22 23
#define GDT_ENTRY_BOOT_TSS	(GDT_ENTRY_BOOT_CS + 2)
#define __BOOT_TSS		(GDT_ENTRY_BOOT_TSS * 8)

24
#ifdef CONFIG_X86_32
25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137
/*
 * The layout of the per-CPU GDT under Linux:
 *
 *   0 - null
 *   1 - reserved
 *   2 - reserved
 *   3 - reserved
 *
 *   4 - unused			<==== new cacheline
 *   5 - unused
 *
 *  ------- start of TLS (Thread-Local Storage) segments:
 *
 *   6 - TLS segment #1			[ glibc's TLS segment ]
 *   7 - TLS segment #2			[ Wine's %fs Win32 segment ]
 *   8 - TLS segment #3
 *   9 - reserved
 *  10 - reserved
 *  11 - reserved
 *
 *  ------- start of kernel segments:
 *
 *  12 - kernel code segment		<==== new cacheline
 *  13 - kernel data segment
 *  14 - default user CS
 *  15 - default user DS
 *  16 - TSS
 *  17 - LDT
 *  18 - PNPBIOS support (16->32 gate)
 *  19 - PNPBIOS support
 *  20 - PNPBIOS support
 *  21 - PNPBIOS support
 *  22 - PNPBIOS support
 *  23 - APM BIOS support
 *  24 - APM BIOS support
 *  25 - APM BIOS support
 *
 *  26 - ESPFIX small SS
 *  27 - per-cpu			[ offset to per-cpu data area ]
 *  28 - unused
 *  29 - unused
 *  30 - unused
 *  31 - TSS for double fault handler
 */
#define GDT_ENTRY_TLS_MIN	6
#define GDT_ENTRY_TLS_MAX 	(GDT_ENTRY_TLS_MIN + GDT_ENTRY_TLS_ENTRIES - 1)

#define GDT_ENTRY_DEFAULT_USER_CS	14

#define GDT_ENTRY_DEFAULT_USER_DS	15

#define GDT_ENTRY_KERNEL_BASE	12

#define GDT_ENTRY_KERNEL_CS		(GDT_ENTRY_KERNEL_BASE + 0)

#define GDT_ENTRY_KERNEL_DS		(GDT_ENTRY_KERNEL_BASE + 1)

#define GDT_ENTRY_TSS			(GDT_ENTRY_KERNEL_BASE + 4)
#define GDT_ENTRY_LDT			(GDT_ENTRY_KERNEL_BASE + 5)

#define GDT_ENTRY_PNPBIOS_BASE		(GDT_ENTRY_KERNEL_BASE + 6)
#define GDT_ENTRY_APMBIOS_BASE		(GDT_ENTRY_KERNEL_BASE + 11)

#define GDT_ENTRY_ESPFIX_SS		(GDT_ENTRY_KERNEL_BASE + 14)
#define __ESPFIX_SS (GDT_ENTRY_ESPFIX_SS * 8)

#define GDT_ENTRY_PERCPU			(GDT_ENTRY_KERNEL_BASE + 15)
#ifdef CONFIG_SMP
#define __KERNEL_PERCPU (GDT_ENTRY_PERCPU * 8)
#else
#define __KERNEL_PERCPU 0
#endif

#define GDT_ENTRY_DOUBLEFAULT_TSS	31

/*
 * The GDT has 32 entries
 */
#define GDT_ENTRIES 32

/* The PnP BIOS entries in the GDT */
#define GDT_ENTRY_PNPBIOS_CS32		(GDT_ENTRY_PNPBIOS_BASE + 0)
#define GDT_ENTRY_PNPBIOS_CS16		(GDT_ENTRY_PNPBIOS_BASE + 1)
#define GDT_ENTRY_PNPBIOS_DS		(GDT_ENTRY_PNPBIOS_BASE + 2)
#define GDT_ENTRY_PNPBIOS_TS1		(GDT_ENTRY_PNPBIOS_BASE + 3)
#define GDT_ENTRY_PNPBIOS_TS2		(GDT_ENTRY_PNPBIOS_BASE + 4)

/* The PnP BIOS selectors */
#define PNP_CS32   (GDT_ENTRY_PNPBIOS_CS32 * 8)	/* segment for calling fn */
#define PNP_CS16   (GDT_ENTRY_PNPBIOS_CS16 * 8)	/* code segment for BIOS */
#define PNP_DS     (GDT_ENTRY_PNPBIOS_DS * 8)	/* data segment for BIOS */
#define PNP_TS1    (GDT_ENTRY_PNPBIOS_TS1 * 8)	/* transfer data segment */
#define PNP_TS2    (GDT_ENTRY_PNPBIOS_TS2 * 8)	/* another data segment */

/* Bottom two bits of selector give the ring privilege level */
#define SEGMENT_RPL_MASK	0x3
/* Bit 2 is table indicator (LDT/GDT) */
#define SEGMENT_TI_MASK		0x4

/* User mode is privilege level 3 */
#define USER_RPL		0x3
/* LDT segment has TI set, GDT has it cleared */
#define SEGMENT_LDT		0x4
#define SEGMENT_GDT		0x0

/*
 * Matching rules for certain types of segments.
 */

/* Matches PNP_CS32 and PNP_CS16 (they must be consecutive) */
#define SEGMENT_IS_PNP_CODE(x)   (((x) & 0xf4) == GDT_ENTRY_PNPBIOS_BASE * 8)


138
#else
139 140
#include <asm/cache.h>

141 142 143
#define GDT_ENTRY_KERNEL32_CS 1
#define GDT_ENTRY_KERNEL_CS 2
#define GDT_ENTRY_KERNEL_DS 3
144

145
#define __KERNEL32_CS   (GDT_ENTRY_KERNEL32_CS * 8)
146 147 148 149 150 151 152

/*
 * we cannot use the same code segment descriptor for user and kernel
 * -- not even in the long flat mode, because of different DPL /kkeil
 * The segment offset needs to contain a RPL. Grr. -AK
 * GDT layout to get 64bit syscall right (sysret hardcodes gdt offsets)
 */
153 154 155 156
#define GDT_ENTRY_DEFAULT_USER32_CS 4
#define GDT_ENTRY_DEFAULT_USER_DS 5
#define GDT_ENTRY_DEFAULT_USER_CS 6
#define __USER32_CS   (GDT_ENTRY_DEFAULT_USER32_CS * 8 + 3)
157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175
#define __USER32_DS	__USER_DS

#define GDT_ENTRY_TSS 8	/* needs two entries */
#define GDT_ENTRY_LDT 10 /* needs two entries */
#define GDT_ENTRY_TLS_MIN 12
#define GDT_ENTRY_TLS_MAX 14

#define GDT_ENTRY_PER_CPU 15	/* Abused to load per CPU data from limit */
#define __PER_CPU_SEG	(GDT_ENTRY_PER_CPU * 8 + 3)

/* TLS indexes for 64bit - hardcoded in arch_prctl */
#define FS_TLS 0
#define GS_TLS 1

#define GS_TLS_SEL ((GDT_ENTRY_TLS_MIN+GS_TLS)*8 + 3)
#define FS_TLS_SEL ((GDT_ENTRY_TLS_MIN+FS_TLS)*8 + 3)

#define GDT_ENTRIES 16

176
#endif
177

178 179 180 181
#define __KERNEL_CS	(GDT_ENTRY_KERNEL_CS * 8)
#define __KERNEL_DS	(GDT_ENTRY_KERNEL_DS * 8)
#define __USER_DS     (GDT_ENTRY_DEFAULT_USER_DS* 8 + 3)
#define __USER_CS     (GDT_ENTRY_DEFAULT_USER_CS* 8 + 3)
182 183 184 185
#ifndef CONFIG_PARAVIRT
#define get_kernel_rpl()  0
#endif

186 187 188 189 190 191 192 193 194 195 196 197
/* User mode is privilege level 3 */
#define USER_RPL		0x3
/* LDT segment has TI set, GDT has it cleared */
#define SEGMENT_LDT		0x4
#define SEGMENT_GDT		0x0

/* Bottom two bits of selector give the ring privilege level */
#define SEGMENT_RPL_MASK	0x3
/* Bit 2 is table indicator (LDT/GDT) */
#define SEGMENT_TI_MASK		0x4

#define IDT_ENTRIES 256
198
#define NUM_EXCEPTION_VECTORS 32
199 200 201 202
#define GDT_SIZE (GDT_ENTRIES * 8)
#define GDT_ENTRY_TLS_ENTRIES 3
#define TLS_SIZE (GDT_ENTRY_TLS_ENTRIES * 8)

203 204
#ifdef __KERNEL__
#ifndef __ASSEMBLY__
205
extern const char early_idt_handlers[NUM_EXCEPTION_VECTORS][10];
206 207 208
#endif
#endif

209
#endif /* ASM_X86__SEGMENT_H */