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Diffstat (limited to 'include/asm-x86/segment_32.h')
| -rw-r--r-- | include/asm-x86/segment_32.h | 148 |
1 files changed, 148 insertions, 0 deletions
diff --git a/include/asm-x86/segment_32.h b/include/asm-x86/segment_32.h new file mode 100644 index 000000000000..597a47c2515f --- /dev/null +++ b/include/asm-x86/segment_32.h @@ -0,0 +1,148 @@ +#ifndef _ASM_SEGMENT_H +#define _ASM_SEGMENT_H + +/* + * 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_ENTRIES 3 +#define GDT_ENTRY_TLS_MIN 6 +#define GDT_ENTRY_TLS_MAX (GDT_ENTRY_TLS_MIN + GDT_ENTRY_TLS_ENTRIES - 1) + +#define TLS_SIZE (GDT_ENTRY_TLS_ENTRIES * 8) + +#define GDT_ENTRY_DEFAULT_USER_CS 14 +#define __USER_CS (GDT_ENTRY_DEFAULT_USER_CS * 8 + 3) + +#define GDT_ENTRY_DEFAULT_USER_DS 15 +#define __USER_DS (GDT_ENTRY_DEFAULT_USER_DS * 8 + 3) + +#define GDT_ENTRY_KERNEL_BASE 12 + +#define GDT_ENTRY_KERNEL_CS (GDT_ENTRY_KERNEL_BASE + 0) +#define __KERNEL_CS (GDT_ENTRY_KERNEL_CS * 8) + +#define GDT_ENTRY_KERNEL_DS (GDT_ENTRY_KERNEL_BASE + 1) +#define __KERNEL_DS (GDT_ENTRY_KERNEL_DS * 8) + +#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 +#define GDT_SIZE (GDT_ENTRIES * 8) + +/* 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) + +/* 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 */ + +/* + * The interrupt descriptor table has room for 256 idt's, + * the global descriptor table is dependent on the number + * of tasks we can have.. + */ +#define IDT_ENTRIES 256 + +/* 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 + +#ifndef CONFIG_PARAVIRT +#define get_kernel_rpl() 0 +#endif +/* + * Matching rules for certain types of segments. + */ + +/* Matches only __KERNEL_CS, ignoring PnP / USER / APM segments */ +#define SEGMENT_IS_KERNEL_CODE(x) (((x) & 0xfc) == GDT_ENTRY_KERNEL_CS * 8) + +/* Matches __KERNEL_CS and __USER_CS (they must be 2 entries apart) */ +#define SEGMENT_IS_FLAT_CODE(x) (((x) & 0xec) == GDT_ENTRY_KERNEL_CS * 8) + +/* Matches PNP_CS32 and PNP_CS16 (they must be consecutive) */ +#define SEGMENT_IS_PNP_CODE(x) (((x) & 0xf4) == GDT_ENTRY_PNPBIOS_BASE * 8) + +#endif |