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/* $OpenBSD: segments.h,v 1.9 2010/11/20 20:11:17 miod Exp $ */
/* $NetBSD: segments.h,v 1.1 2003/04/26 18:39:47 fvdl Exp $ */
/*-
* Copyright (c) 1995, 1997
* Charles M. Hannum. All rights reserved.
* 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.
* 3. 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.
*
* @(#)segments.h 7.1 (Berkeley) 5/9/91
*/
/*
* Adapted for NetBSD/amd64 by fvdl@wasabisystems.com.
*/
/*
* 386 Segmentation Data Structures and definitions
* William F. Jolitz (william@ernie.berkeley.edu) 6/20/1989
*/
#ifndef _AMD64_SEGMENTS_H_
#define _AMD64_SEGMENTS_H_
/*
* Selectors
*/
#define ISPL(s) ((s) & SEL_RPL) /* what is the priority level of a selector */
#define SEL_KPL 0 /* kernel privilege level */
#define SEL_UPL 3 /* user privilege level */
#define SEL_RPL 3 /* requester's privilege level mask */
#define ISLDT(s) ((s) & SEL_LDT) /* is it local or global */
#define SEL_LDT 4 /* local descriptor table */
#define SYSSEL_START (NGDT_MEM << 3)
#define GDT_SIZE (SYSSEL_START + (NGDT_SYS << 4))
/*
* These define the index not from the start of the GDT, but from
* the part of the GDT that they're allocated from.
* First NGDT_MEM entries are 8-byte descriptors for CS and DS.
* Next NGDT_SYS entries are 16-byte descriptors defining TSSs.
*/
#define IDXSEL(s) (((s) >> 3) & 0x1fff)
#define IDXDYNSEL(s) ((((s) & ~SEL_RPL) - DYNSEL_START) >> 4)
#define GSEL(s,r) (((s) << 3) | r)
#define GSYSSEL(s,r) ((((s) << 4) + SYSSEL_START) | r)
#define GDYNSEL(s,r) ((((s) << 4) + DYNSEL_START) | r | SEL_KPL)
#define LSEL(s,r) ((s) | r | SEL_LDT)
#define USERMODE(c, f) (ISPL(c) == SEL_UPL)
#define KERNELMODE(c, f) (ISPL(c) == SEL_KPL)
#ifndef _LOCORE
/*
* Memory and System segment descriptors
*/
/*
* Below is used for TSS and LDT.
*/
struct sys_segment_descriptor {
/*BITFIELDTYPE*/ u_int64_t sd_lolimit:16;/* segment extent (lsb) */
/*BITFIELDTYPE*/ u_int64_t sd_lobase:24;/* segment base address (lsb) */
/*BITFIELDTYPE*/ u_int64_t sd_type:5; /* segment type */
/*BITFIELDTYPE*/ u_int64_t sd_dpl:2; /* segment descriptor priority level */
/*BITFIELDTYPE*/ u_int64_t sd_p:1; /* segment descriptor present */
/*BITFIELDTYPE*/ u_int64_t sd_hilimit:4;/* segment extent (msb) */
/*BITFIELDTYPE*/ u_int64_t sd_xx1:3; /* avl, long and def32 (not used) */
/*BITFIELDTYPE*/ u_int64_t sd_gran:1; /* limit granularity (byte/page) */
/*BITFIELDTYPE*/ u_int64_t sd_hibase:40;/* segment base address (msb) */
/*BITFIELDTYPE*/ u_int64_t sd_xx2:8; /* reserved */
/*BITFIELDTYPE*/ u_int64_t sd_zero:5; /* must be zero */
/*BITFIELDTYPE*/ u_int64_t sd_xx3:19; /* reserved */
} __packed;
/*
* Below is used for cs, ds, etc.
*/
struct mem_segment_descriptor {
unsigned int sd_lolimit:16; /* segment extent (lsb) */
unsigned int sd_lobase:24; /* segment base address (lsb) */
unsigned int sd_type:5; /* segment type */
unsigned int sd_dpl:2; /* segment descriptor priority level */
unsigned int sd_p:1; /* segment descriptor present */
unsigned int sd_hilimit:4; /* segment extent (msb) */
unsigned int sd_avl:1; /* available */
unsigned int sd_long:1; /* long mode */
unsigned int sd_def32:1; /* default 32 vs 16 bit size */
unsigned int sd_gran:1; /* limit granularity (byte/page) */
unsigned int sd_hibase:8; /* segment base address (msb) */
} __packed;
/*
* Gate descriptors (e.g. indirect descriptors)
*/
struct gate_descriptor {
/*BITFIELDTYPE*/ u_int64_t gd_looffset:16;/* gate offset (lsb) */
/*BITFIELDTYPE*/ u_int64_t gd_selector:16;/* gate segment selector */
/*BITFIELDTYPE*/ u_int64_t gd_ist:3; /* IST select */
/*BITFIELDTYPE*/ u_int64_t gd_xx1:5; /* reserved */
/*BITFIELDTYPE*/ u_int64_t gd_type:5; /* segment type */
/*BITFIELDTYPE*/ u_int64_t gd_dpl:2; /* segment descriptor priority level */
/*BITFIELDTYPE*/ u_int64_t gd_p:1; /* segment descriptor present */
/*BITFIELDTYPE*/ u_int64_t gd_hioffset:48;/* gate offset (msb) */
/*BITFIELDTYPE*/ u_int64_t gd_xx2:8; /* reserved */
/*BITFIELDTYPE*/ u_int64_t gd_zero:5; /* must be zero */
/*BITFIELDTYPE*/ u_int64_t gd_xx3:19; /* reserved */
} __packed;
/*
* region descriptors, used to load gdt/idt tables before segments yet exist.
*/
struct region_descriptor {
u_int16_t rd_limit; /* segment extent */
u_int64_t rd_base; /* base address */
} __packed;
#ifdef _KERNEL
#if 0
extern struct sys_segment_descriptor *ldt;
#endif
extern struct gate_descriptor *idt;
extern char *gdtstore;
void setgate(struct gate_descriptor *, void *, int, int, int, int);
void unsetgate(struct gate_descriptor *);
void setregion(struct region_descriptor *, void *, u_int16_t);
void set_sys_segment(struct sys_segment_descriptor *, void *, size_t,
int, int, int);
void set_mem_segment(struct mem_segment_descriptor *, void *, size_t,
int, int, int, int, int);
int idt_vec_alloc(int, int);
void idt_vec_set(int, void (*)(void));
void idt_vec_free(int);
void cpu_init_idt(void);
#endif /* _KERNEL */
#endif /* !_LOCORE */
/* system segments and gate types */
#define SDT_SYSNULL 0 /* system null */
#define SDT_SYS286TSS 1 /* system 286 TSS available */
#define SDT_SYSLDT 2 /* system local descriptor table */
#define SDT_SYS286BSY 3 /* system 286 TSS busy */
#define SDT_SYS286CGT 4 /* system 286 call gate */
#define SDT_SYSTASKGT 5 /* system task gate */
#define SDT_SYS286IGT 6 /* system 286 interrupt gate */
#define SDT_SYS286TGT 7 /* system 286 trap gate */
#define SDT_SYSNULL2 8 /* system null again */
#define SDT_SYS386TSS 9 /* system 386 TSS available */
#define SDT_SYSNULL3 10 /* system null again */
#define SDT_SYS386BSY 11 /* system 386 TSS busy */
#define SDT_SYS386CGT 12 /* system 386 call gate */
#define SDT_SYSNULL4 13 /* system null again */
#define SDT_SYS386IGT 14 /* system 386 interrupt gate */
#define SDT_SYS386TGT 15 /* system 386 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 acessed */
#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 */
/* is memory segment descriptor pointer ? */
#define ISMEMSDP(s) ((s->d_type) >= SDT_MEMRO && \
(s->d_type) <= SDT_MEMERAC)
/* is 286 gate descriptor pointer ? */
#define IS286GDP(s) ((s->d_type) >= SDT_SYS286CGT && \
(s->d_type) < SDT_SYS286TGT)
/* is 386 gate descriptor pointer ? */
#define IS386GDP(s) ((s->d_type) >= SDT_SYS386CGT && \
(s->d_type) < SDT_SYS386TGT)
/* is gate descriptor pointer ? */
#define ISGDP(s) (IS286GDP(s) || IS386GDP(s))
/* is segment descriptor pointer ? */
#define ISSDP(s) (ISMEMSDP(s) || !ISGDP(s))
/* is system segment descriptor pointer ? */
#define ISSYSSDP(s) (!ISMEMSDP(s) && !ISGDP(s))
/*
* Segment Protection Exception code bits
*/
#define SEGEX_EXT 0x01 /* recursive or externally induced */
#define SEGEX_IDT 0x02 /* interrupt descriptor table */
#define SEGEX_TI 0x04 /* local descriptor table */
/*
* Entries in the Interrupt Descriptor Table (IDT)
*/
#define NIDT 256
#define NRSVIDT 32 /* reserved entries for cpu exceptions */
/*
* Entries in the Global Descriptor Table (GDT)
* The code and data descriptors must come first. There
* are NGDT_MEM of them.
*
* Then comes the predefined TSS descriptor.
* There are NGDT_SYS of them.
*
* The particular order of the UCODE32, UDATA, and UCODE descriptors is
* required by the syscall/sysret instructions.
*/
#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 32bit code descriptor (unused) */
#define GUDATA_SEL 4 /* User data descriptor */
#define GUCODE_SEL 5 /* User code descriptor */
#define NGDT_MEM 6
#define GPROC0_SEL 0 /* common TSS */
#define NGDT_SYS 1
#define GDT_SYS_OFFSET (NGDT_MEM << 3)
#define GDT_ADDR_MEM(s,i) \
((struct mem_segment_descriptor *)((s) + ((i) << 3)))
#define GDT_ADDR_SYS(s,i) \
((struct sys_segment_descriptor *)((s) + (((i) << 4) + SYSSEL_START)))
/*
* Checks for valid user selectors.
*/
#define VALID_USER_CSEL(s) \
((s) == GSEL(GUCODE_SEL, SEL_UPL))
#define VALID_USER_DSEL(s) \
((s) == GSEL(GUDATA_SEL, SEL_UPL))
#endif /* _AMD64_SEGMENTS_H_ */
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