| #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 |
