segments.h revision 5f9a4ecd4106e277223521401655c1bba6615d88
/*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#ifndef _SYS_SEGMENTS_H
#define _SYS_SEGMENTS_H
#pragma ident "%Z%%M% %I% %E% SMI"
#ifdef __cplusplus
extern "C" {
#endif
/*
* Copyright (c) 1989, 1990 William F. Jolitz
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* William Jolitz.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* from: @(#)segments.h 7.1 (Berkeley) 5/9/91
* $FreeBSD: src/sys/i386/include/segments.h,v 1.34 2003/09/10 01:07:04
* jhb Exp $
*
* 386 Segmentation Data Structures and definitions
* William F. Jolitz (william@ernie.berkeley.edu) 6/20/1989
*/
/*
* Selector register format
* CS, DS, ES, FS, GS, SS
*
* 15 3 2 1 0
* +---------------------+---+----+
* | SI |TI |RPL |
* +---------------------+---+----+
*
* SI = selector index
* TI = table indicator (0 = GDT, 1 = LDT)
* RPL = requestor privilege level
*/
#if !defined(_ASM) || defined(__GNUC_AS__)
#else
#define IDXTOSEL(s) [s << 3]
#endif
#define SEL_KPL 0 /* kernel priority level */
#ifndef _ASM
/*
* Hardware descriptor table register format for GDT and IDT.
*/
#if defined(__amd64)
#pragma pack(2)
typedef struct {
} desctbr_t;
#pragma pack()
#pragma pack(2)
typedef struct {
} desctbr_t;
#pragma pack()
#endif /* __i386 */
/*
* Functions for loading and storing descriptor table
* registers.
*/
extern void wr_ldtr(selector_t);
extern selector_t rd_ldtr(void);
extern void wr_tsr(selector_t);
#if defined(__amd64)
extern void clr_ldt_sregs(void);
#endif
#if !defined(__amd64)
/*
* User segment descriptors (code and data).
* Legacy mode 64-bits wide.
*/
typedef struct user_desc {
} user_desc_t;
#else /* __amd64 */
/*
* User segment descriptors.
* Long mode 64-bits wide.
*
* In 32-bit compatibility mode (%cs:usd_long=0) all fields are interpreted
* as in legacy mode for both code and data.
*
* In 64-bit mode (%cs:usd_long=1) code segments only have the conforming
* bit in usd_type, usd_dpl, usd_p, usd_long and usd_def32=0. usd_def32
* must be zero in 64-bit mode. Setting it to 1 is reserved for future use.
* All other fields are loaded but ignored by hardware.
*
* 64-bit data segments only have usd_p. All other fields are loaded but
* ignored by hardware when in 64-bit mode.
*/
typedef struct user_desc {
} user_desc_t;
#endif /* __amd64 */
#if !defined(__amd64)
/*
* System segment descriptors for LDT and TSS segments.
* Legacy mode 64-bits wide.
*/
typedef struct system_desc {
#else /* __amd64 */
/*
* System segment descriptors for LDT and TSS segments.
* Long mode 128-bits wide.
*
* 32-bit LDT and TSS descriptor types are redefined to 64-bit equivalents.
* All other legacy types are reserved and illegal.
*/
typedef struct system_desc {
#endif /* __amd64 */
#if !defined(__amd64)
/*
* System gate segment descriptors for interrupt, trap, call and task gates.
* Legacy mode 64-bits wide.
*/
typedef struct gate_desc {
} gate_desc_t;
#else /* __amd64 */
/*
* System segment descriptors for interrupt, trap and call gates.
* Long mode 128-bits wide.
*
* 32-bit interrupt, trap and call gate types are redefined to 64-bit
* equivalents. Task gates along with all other legacy types are reserved
* and illegal.
*/
typedef struct gate_desc {
} gate_desc_t;
#endif /* __amd64 */
/*
* functions for initializing and updating segment descriptors.
*/
#if defined(__amd64)
#endif /* __i386 */
#endif /* _ASM */
/*
* Common segment parameter defintions for granularity, default
* operand size and operaton mode.
*/
#define SDP_BYTES 0 /* segment limit scaled to bytes */
/*
* System segments and gate types.
*
* In long mode i386 32-bit ldt, tss, call, interrupt and trap gate
* types are redefined into 64-bit equivalents.
*/
#define SDT_SYSNULL 0 /* system null */
/*
* Memory segment types.
*
* While in long mode expand-down, writable and accessed type field
* attributes are ignored. Only the conforming bit is loaded by hardware
* for long mode code segment descriptors.
*/
/*
* Entries in the Interrupt Descriptor Table (IDT)
*/
#define IDT_DE 0 /* #DE: Divide Error */
/*
* Entries in the Global Descriptor Table (GDT)
*
* We make sure to space the system descriptors (LDT's, TSS')
* such that they are double gdt slot aligned. This is because
* in long mode system segment decriptors expand to 128 bits.
*
* GDT_LWPFS and GDT_LWPGS must be the same for both 32 and 64-bit
* kernels. See setup_context in libc.
*/
#if defined(__amd64)
#define GDT_NULL 0 /* null */
/*
* This selector is only used in the temporary GDT used to bring additional
* CPUs from 16-bit real mode into long mode in real_mode_start().
*/
#define GDT_NULL 0 /* null */
#endif /* __i386 */
/*
* Convenient selector definitions.
*/
#if defined(__amd64)
#endif /* __amd64 */
#if defined(__amd64)
#else
#endif
/*
* Entries in default Local Descriptor Table (LDT) for every process.
*/
#define LDT_SYSCALL 0 /* call gate for libc.a (obsolete) */
#ifndef _ASM
extern desctbr_t idt0_default_reg;
extern user_desc_t zero_udesc;
extern system_desc_t zero_sdesc;
#if defined(__amd64)
extern user_desc_t zero_u32desc;
#endif
#if defined(__i386)
#endif /* __i386 */
extern void xmtrap();
extern void fasttrap();
extern void dtrace_fasttrap(), dtrace_ret();
#if !defined(__amd64)
extern void pentium_pftrap();
#endif
#endif /* _ASM */
#ifdef __cplusplus
}
#endif
#endif /* _SYS_SEGMENTS_H */