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authorAl Viro <viro@zeniv.linux.org.uk>2008-08-18 03:05:42 +0200
committerH. Peter Anvin <hpa@zytor.com>2008-10-23 07:55:20 +0200
commitbb8985586b7a906e116db835c64773b7a7d51663 (patch)
treede93ae58e88cc563d95cc124a73f3930594c6100 /arch/x86/include/asm/segment.h
parentx86, um: initial part of asm-um move (diff)
downloadlinux-bb8985586b7a906e116db835c64773b7a7d51663.tar.xz
linux-bb8985586b7a906e116db835c64773b7a7d51663.zip
x86, um: ... and asm-x86 move
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Diffstat (limited to 'arch/x86/include/asm/segment.h')
-rw-r--r--arch/x86/include/asm/segment.h209
1 files changed, 209 insertions, 0 deletions
diff --git a/arch/x86/include/asm/segment.h b/arch/x86/include/asm/segment.h
new file mode 100644
index 000000000000..5d6e69454891
--- /dev/null
+++ b/arch/x86/include/asm/segment.h
@@ -0,0 +1,209 @@
+#ifndef ASM_X86__SEGMENT_H
+#define ASM_X86__SEGMENT_H
+
+/* 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)))
+
+/* 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)
+
+#define GDT_ENTRY_BOOT_TSS (GDT_ENTRY_BOOT_CS + 2)
+#define __BOOT_TSS (GDT_ENTRY_BOOT_TSS * 8)
+
+#ifdef CONFIG_X86_32
+/*
+ * 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)
+
+
+#else
+#include <asm/cache.h>
+
+#define GDT_ENTRY_KERNEL32_CS 1
+#define GDT_ENTRY_KERNEL_CS 2
+#define GDT_ENTRY_KERNEL_DS 3
+
+#define __KERNEL32_CS (GDT_ENTRY_KERNEL32_CS * 8)
+
+/*
+ * 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)
+ */
+#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)
+#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
+
+#endif
+
+#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)
+#ifndef CONFIG_PARAVIRT
+#define get_kernel_rpl() 0
+#endif
+
+/* 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
+#define NUM_EXCEPTION_VECTORS 32
+#define GDT_SIZE (GDT_ENTRIES * 8)
+#define GDT_ENTRY_TLS_ENTRIES 3
+#define TLS_SIZE (GDT_ENTRY_TLS_ENTRIES * 8)
+
+#ifdef __KERNEL__
+#ifndef __ASSEMBLY__
+extern const char early_idt_handlers[NUM_EXCEPTION_VECTORS][10];
+#endif
+#endif
+
+#endif /* ASM_X86__SEGMENT_H */