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-rw-r--r--include/asm-x86/segment_32.h148
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 00000000000..597a47c2515
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+++ 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