freebsd-src/sys/amd64/include/segments.h
Konstantin Belousov 575a30d883 Fix inconsistencies in the comments.
MFC after:	1 week
2008-09-08 08:58:29 +00:00

224 lines
9.0 KiB
C

/*-
* 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
* documentation and/or other materials provided with the distribution.
* 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
* $FreeBSD$
*/
#ifndef _MACHINE_SEGMENTS_H_
#define _MACHINE_SEGMENTS_H_
/*
* AMD64 Segmentation Data Structures and definitions
*/
/*
* Selectors
*/
#define SEL_RPL_MASK 3 /* requester priv level */
#define ISPL(s) ((s)&3) /* what is the priority level of a selector */
#define SEL_KPL 0 /* kernel priority level */
#define SEL_UPL 3 /* user priority level */
#define ISLDT(s) ((s)&SEL_LDT) /* is it local or global */
#define SEL_LDT 4 /* local descriptor table */
#define IDXSEL(s) (((s)>>3) & 0x1fff) /* index of selector */
#define LSEL(s,r) (((s)<<3) | SEL_LDT | r) /* a local selector */
#define GSEL(s,r) (((s)<<3) | r) /* a global selector */
/*
* User segment descriptors (%cs, %ds etc for compatability apps. 64 bit wide)
* For long-mode apps, %cs only has the conforming bit in sd_type, the sd_dpl,
* sd_p, sd_l and sd_def32 which must be zero). %ds only has sd_p.
*/
struct user_segment_descriptor {
u_int64_t sd_lolimit:16; /* segment extent (lsb) */
u_int64_t sd_lobase:24; /* segment base address (lsb) */
u_int64_t sd_type:5; /* segment type */
u_int64_t sd_dpl:2; /* segment descriptor priority level */
u_int64_t sd_p:1; /* segment descriptor present */
u_int64_t sd_hilimit:4; /* segment extent (msb) */
u_int64_t sd_xx:1; /* unused */
u_int64_t sd_long:1; /* long mode (cs only) */
u_int64_t sd_def32:1; /* default 32 vs 16 bit size */
u_int64_t sd_gran:1; /* limit granularity (byte/page units)*/
u_int64_t sd_hibase:8; /* segment base address (msb) */
} __packed;
/*
* System segment descriptors (128 bit wide)
*/
struct system_segment_descriptor {
u_int64_t sd_lolimit:16; /* segment extent (lsb) */
u_int64_t sd_lobase:24; /* segment base address (lsb) */
u_int64_t sd_type:5; /* segment type */
u_int64_t sd_dpl:2; /* segment descriptor priority level */
u_int64_t sd_p:1; /* segment descriptor present */
u_int64_t sd_hilimit:4; /* segment extent (msb) */
u_int64_t sd_xx0:3; /* unused */
u_int64_t sd_gran:1; /* limit granularity (byte/page units)*/
u_int64_t sd_hibase:40 __packed;/* segment base address (msb) */
u_int64_t sd_xx1:8;
u_int64_t sd_mbz:5; /* MUST be zero */
u_int64_t sd_xx2:19;
} __packed;
/*
* Gate descriptors (e.g. indirect descriptors, trap, interrupt etc. 128 bit)
* Only interrupt and trap gates have gd_ist.
*/
struct gate_descriptor {
u_int64_t gd_looffset:16; /* gate offset (lsb) */
u_int64_t gd_selector:16; /* gate segment selector */
u_int64_t gd_ist:3; /* IST table index */
u_int64_t gd_xx:5; /* unused */
u_int64_t gd_type:5; /* segment type */
u_int64_t gd_dpl:2; /* segment descriptor priority level */
u_int64_t gd_p:1; /* segment descriptor present */
u_int64_t gd_hioffset:48 __packed; /* gate offset (msb) */
u_int64_t sd_xx1:32;
} __packed;
/* system segments and gate types */
#define SDT_SYSNULL 0 /* system null */
#define SDT_SYSLDT 2 /* system 64 bit local descriptor table */
#define SDT_SYSTSS 9 /* system available 64 bit TSS */
#define SDT_SYSBSY 11 /* system busy 64 bit TSS */
#define SDT_SYSCGT 12 /* system 64 bit call gate */
#define SDT_SYSIGT 14 /* system 64 bit interrupt gate */
#define SDT_SYSTGT 15 /* system 64 bit trap gate */
/* memory segment types */
#define SDT_MEMRO 16 /* memory read only */
#define SDT_MEMROA 17 /* memory read only accessed */
#define SDT_MEMRW 18 /* memory read write */
#define SDT_MEMRWA 19 /* memory read write accessed */
#define SDT_MEMROD 20 /* memory read only expand dwn limit */
#define SDT_MEMRODA 21 /* memory read only expand dwn limit accessed */
#define SDT_MEMRWD 22 /* memory read write expand dwn limit */
#define SDT_MEMRWDA 23 /* memory read write expand dwn limit accessed */
#define SDT_MEME 24 /* memory execute only */
#define SDT_MEMEA 25 /* memory execute only accessed */
#define SDT_MEMER 26 /* memory execute read */
#define SDT_MEMERA 27 /* memory execute read accessed */
#define SDT_MEMEC 28 /* memory execute only conforming */
#define SDT_MEMEAC 29 /* memory execute only accessed conforming */
#define SDT_MEMERC 30 /* memory execute read conforming */
#define SDT_MEMERAC 31 /* memory execute read accessed conforming */
/*
* Software definitions are in this convenient format,
* which are translated into inconvenient segment descriptors
* when needed to be used by the 386 hardware
*/
struct soft_segment_descriptor {
unsigned long ssd_base; /* segment base address */
unsigned long ssd_limit; /* segment extent */
unsigned long ssd_type:5; /* segment type */
unsigned long ssd_dpl:2; /* segment descriptor priority level */
unsigned long ssd_p:1; /* segment descriptor present */
unsigned long ssd_long:1; /* long mode (for %cs) */
unsigned long ssd_def32:1; /* default 32 vs 16 bit size */
unsigned long ssd_gran:1; /* limit granularity (byte/page units)*/
} __packed;
/*
* region descriptors, used to load gdt/idt tables before segments yet exist.
*/
struct region_descriptor {
unsigned long rd_limit:16; /* segment extent */
unsigned long rd_base:64 __packed; /* base address */
} __packed;
/*
* Size of IDT table
*/
#define NIDT 256 /* 32 reserved, 16 h/w, 0 s/w, linux's 0x80 */
#define NRSVIDT 32 /* reserved entries for cpu exceptions */
/*
* Entries in the Interrupt Descriptor Table (IDT)
*/
#define IDT_DE 0 /* #DE: Divide Error */
#define IDT_DB 1 /* #DB: Debug */
#define IDT_NMI 2 /* Nonmaskable External Interrupt */
#define IDT_BP 3 /* #BP: Breakpoint */
#define IDT_OF 4 /* #OF: Overflow */
#define IDT_BR 5 /* #BR: Bound Range Exceeded */
#define IDT_UD 6 /* #UD: Undefined/Invalid Opcode */
#define IDT_NM 7 /* #NM: No Math Coprocessor */
#define IDT_DF 8 /* #DF: Double Fault */
#define IDT_FPUGP 9 /* Coprocessor Segment Overrun */
#define IDT_TS 10 /* #TS: Invalid TSS */
#define IDT_NP 11 /* #NP: Segment Not Present */
#define IDT_SS 12 /* #SS: Stack Segment Fault */
#define IDT_GP 13 /* #GP: General Protection Fault */
#define IDT_PF 14 /* #PF: Page Fault */
#define IDT_MF 16 /* #MF: FPU Floating-Point Error */
#define IDT_AC 17 /* #AC: Alignment Check */
#define IDT_MC 18 /* #MC: Machine Check */
#define IDT_XF 19 /* #XF: SIMD Floating-Point Exception */
#define IDT_IO_INTS NRSVIDT /* Base of IDT entries for I/O interrupts. */
#define IDT_SYSCALL 0x80 /* System Call Interrupt Vector */
/*
* Entries in the Global Descriptor Table (GDT)
*/
#define GNULL_SEL 0 /* Null Descriptor */
#define GCODE_SEL 1 /* Kernel Code Descriptor */
#define GDATA_SEL 2 /* Kernel Data Descriptor */
#define GUCODE32_SEL 3 /* User 32 bit code Descriptor */
#define GUDATA_SEL 4 /* User 32/64 bit Data Descriptor */
#define GUCODE_SEL 5 /* User 64 bit Code Descriptor */
#define GPROC0_SEL 6 /* TSS for entering kernel etc */
/* slot 7 is second half of GPROC0_SEL */
#define GUGS32_SEL 8 /* User 32 bit GS Descriptor */
#define NGDT 9
#ifdef _KERNEL
extern struct user_segment_descriptor gdt[];
extern struct soft_segment_descriptor gdt_segs[];
extern struct gate_descriptor *idt;
extern struct region_descriptor r_gdt, r_idt;
void lgdt(struct region_descriptor *rdp);
void sdtossd(struct user_segment_descriptor *sdp,
struct soft_segment_descriptor *ssdp);
void ssdtosd(struct soft_segment_descriptor *ssdp,
struct user_segment_descriptor *sdp);
void ssdtosyssd(struct soft_segment_descriptor *ssdp,
struct system_segment_descriptor *sdp);
#endif /* _KERNEL */
#endif /* !_MACHINE_SEGMENTS_H_ */