linux/include/asm-i386/segment.h
Rusty Russell d3561b7fa0 [PATCH] paravirt: header and stubs for paravirtualisation
Create a paravirt.h header for all the critical operations which need to be
replaced with hypervisor calls, and include that instead of defining native
operations, when CONFIG_PARAVIRT.

This patch does the dumbest possible replacement of paravirtualized
instructions: calls through a "paravirt_ops" structure.  Currently these are
function implementations of native hardware: hypervisors will override the ops
structure with their own variants.

All the pv-ops functions are declared "fastcall" so that a specific
register-based ABI is used, to make inlining assember easier.

And:

+From: Andy Whitcroft <apw@shadowen.org>

The paravirt ops introduce a 'weak' attribute onto memory_setup().
Code ordering leads to the following warnings on x86:

    arch/i386/kernel/setup.c:651: warning: weak declaration of
                `memory_setup' after first use results in unspecified behavior

Move memory_setup() to avoid this.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
2006-12-07 02:14:07 +01:00

137 lines
3.9 KiB
C

#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 - PDA [ per-cpu private 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_PDA (GDT_ENTRY_KERNEL_BASE + 15)
#define __KERNEL_PDA (GDT_ENTRY_PDA * 8)
#define GDT_ENTRY_DOUBLEFAULT_TSS 31
/*
* The GDT has 32 entries
*/
#define GDT_ENTRIES 32
#define GDT_SIZE (GDT_ENTRIES * 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)
/* 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
#endif