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