LCOM1920-T02G10

/*        $NetBSD: segments.h,v 1.54 2011/04/26 15:51:23 joerg Exp $        */

/*-

 * 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

 */

/*-

 * Copyright (c) 1995, 1997

 *        Charles M. Hannum.  All rights reserved.

 * Copyright (c) 1989, 1990 William F. Jolitz

 *

 * 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. 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.

 *

 *        @(#)segments.h        7.1 (Berkeley) 5/9/91

 */

/*

 * 386 Segmentation Data Structures and definitions

 *        William F. Jolitz (william@ernie.berkeley.edu) 6/20/1989

 */

#ifndef _I386_SEGMENTS_H_

#define _I386_SEGMENTS_H_

#ifdef _KERNEL_OPT

#include "opt_xen.h"

#endif

/*

 * Selectors

 */

#define        ISPL(s)                ((s) & SEL_RPL)        /* what is the priority level of a selector */

#ifndef XEN

#define        SEL_KPL                0                /* kernel privilege level */

#else

#define        SEL_XEN                0                /* Xen privilege level */

#define        SEL_KPL                1                /* kernel privilege level */

#endif /* XEN */

#define        SEL_UPL                3                /* user privilege level */

#define        SEL_RPL                3                /* requester's privilege level mask */

#ifdef XEN

#define        CHK_UPL                2                /* user privilege level mask */

#else

#define CHK_UPL                SEL_RPL

#endif /* XEN */

#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        IDXSELN(s)        (((s) >> 3))                        /* index of selector */

#define        GSEL(s,r)        (((s) << 3) | r)                /* a global selector */

#define        LSEL(s,r)        (((s) << 3) | r | SEL_LDT)        /* a local selector */

#define        GSYSSEL(s,r)        GSEL(s,r)        /* compat with amd64 */

#if defined(_KERNEL_OPT)

#include "opt_vm86.h"

#endif

#ifdef VM86

#define        USERMODE(c, f)                (ISPL(c) == SEL_UPL || ((f) & PSL_VM) != 0)

#define        KERNELMODE(c, f)        (ISPL(c) == SEL_KPL && ((f) & PSL_VM) == 0)

#else

#define        USERMODE(c, f)                (ISPL(c) == SEL_UPL)

#define        KERNELMODE(c, f)        (ISPL(c) == SEL_KPL)

#endif

#ifndef _LOCORE

#if __GNUC__ == 2 && __GNUC_MINOR__ < 7

#pragma pack(1)

#endif

/*

 * Memory and System segment descriptors

 */

struct segment_descriptor {

        unsigned sd_lolimit:16;                /* segment extent (lsb) */

        unsigned sd_lobase:24;                /* segment base address (lsb) */

        unsigned sd_type:5;                /* segment type */

        unsigned sd_dpl:2;                /* segment descriptor priority level */

        unsigned sd_p:1;                /* segment descriptor present */

        unsigned sd_hilimit:4;                /* segment extent (msb) */

        unsigned sd_xx:2;                /* unused */

        unsigned sd_def32:1;                /* default 32 vs 16 bit size */

        unsigned sd_gran:1;                /* limit granularity (byte/page) */

        unsigned sd_hibase:8;                /* segment base address (msb) */

} __packed;

/*

 * Gate descriptors (e.g. indirect descriptors)

 */

struct gate_descriptor {

        unsigned gd_looffset:16;        /* gate offset (lsb) */

        unsigned gd_selector:16;        /* gate segment selector */

        unsigned gd_stkcpy:5;                /* number of stack wds to cpy */

        unsigned gd_xx:3;                /* unused */

        unsigned gd_type:5;                /* segment type */

        unsigned gd_dpl:2;                /* segment descriptor priority level */

        unsigned gd_p:1;                /* segment descriptor present */

        unsigned gd_hioffset:16;        /* gate offset (msb) */

} __packed;

struct ldt_descriptor {

        vaddr_t ld_base;

        uint32_t ld_entries;

} __packed;

/*

 * Generic descriptor

 */

union descriptor {

        struct segment_descriptor sd;

        struct gate_descriptor gd;

        struct ldt_descriptor ld;

        uint32_t raw[2];

        uint64_t raw64;

} __packed;

/*

 * region descriptors, used to load gdt/idt tables before segments yet exist.

 */

struct region_descriptor {

        unsigned rd_limit:16;                /* segment extent */

        unsigned rd_base:32;                /* base address  */

} __packed;

#if __GNUC__ == 2 && __GNUC_MINOR__ < 7

#pragma pack(4)

#endif

#ifdef _KERNEL

extern union descriptor *gdt, *ldt;

extern struct gate_descriptor *idt;

void setgate(struct gate_descriptor *, void *, int, int, int, int);

void setregion(struct region_descriptor *, void *, size_t);

void setsegment(struct segment_descriptor *, const void *, size_t, int, int,

    int, int);

void setgdt(int, const void *, size_t, int, int, int, int);

void unsetgate(struct gate_descriptor *);

void cpu_init_idt(void);

void update_descriptor(union descriptor *, union descriptor *);

#if !defined(XEN)

void idt_init(void);

void idt_vec_reserve(int);

int idt_vec_alloc(int, int);

void idt_vec_set(int, void (*)(void));

void idt_vec_free(int);

#endif

#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 */

#define SDTYPE(p)        (((const struct segment_descriptor *)(p))->sd_type)

/* is memory segment descriptor pointer ? */

#define ISMEMSDP(s)        (SDTYPE(s) >= SDT_MEMRO && \

                         SDTYPE(s) <= SDT_MEMERAC)

/* is 286 gate descriptor pointer ? */

#define IS286GDP(s)        (SDTYPE(s) >= SDT_SYS286CGT && \

                         SDTYPE(s) < SDT_SYS286TGT)

/* is 386 gate descriptor pointer ? */

#define IS386GDP(s)        (SDTYPE(s) >= SDT_SYS386CGT && \

                         SDTYPE(s) < 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).

 *

 * NB: If you change GBIOSCODE/GBIOSDATA, you *must* rebuild arch/i386/

 * bioscall/biostramp.inc, as that relies on GBIOSCODE/GBIOSDATA and a

 * normal kernel build does not rebuild it (it's merely included whole-

 * sale from i386/bioscall.s)

 *

 * Also, note that the GEXTBIOSDATA_SEL selector is special, as it maps

 * to the value 0x0040 (when created as a KPL global selector).  Some

 * BIOSes reference the extended BIOS data area at segment 0040 in a non

 * relocatable fashion (even when in protected mode); mapping the zero page

 * via the GEXTBIOSDATA_SEL allows these buggy BIOSes to continue to work

 * under NetBSD.

 *

 * The order if the first 5 descriptors is special; the sysenter/sysexit

 * instructions depend on them.

 */

#define        GNULL_SEL        0        /* Null descriptor */

#define        GCODE_SEL        1        /* Kernel code descriptor */

#define        GDATA_SEL        2        /* Kernel data descriptor */

#define        GUCODE_SEL        3        /* User code descriptor */

#define        GUDATA_SEL        4        /* User data descriptor */

#define        GLDT_SEL        5        /* Default LDT descriptor */

#define GCPU_SEL        6        /* per-CPU segment */

#define        GEXTBIOSDATA_SEL 8        /* magic to catch BIOS refs to EBDA */

#define        GAPM32CODE_SEL        9        /* 3 APM segments must be consecutive */

#define        GAPM16CODE_SEL        10        /* and in the specified order: code32 */

#define        GAPMDATA_SEL        11        /* code16 and then data per APM spec */

#define        GBIOSCODE_SEL        12

#define        GBIOSDATA_SEL        13

#define        GPNPBIOSCODE_SEL 14

#define        GPNPBIOSDATA_SEL 15

#define        GPNPBIOSSCRATCH_SEL 16

#define        GPNPBIOSTRAMP_SEL 17

#define GTRAPTSS_SEL        18

#define GIPITSS_SEL        19

#define GUCODEBIG_SEL        20        /* User code with executable stack */

#define        GUFS_SEL        21        /* Per-thread %fs */

#define        GUGS_SEL        22        /* Per-thread %gs */

#define        NGDT                23

/*

 * Entries in the Local Descriptor Table (LDT).

 * DO NOT ADD KERNEL DATA/CODE SEGMENTS TO THIS TABLE.

 */

#define        LSYS5CALLS_SEL        0        /* iBCS system call gate */

#define        LSYS5SIGR_SEL        1        /* iBCS sigreturn gate */

#define        LUCODE_SEL        2        /* User code descriptor */

#define        LUDATA_SEL        3        /* User data descriptor */

#define        LSOL26CALLS_SEL        4        /* Solaris 2.6 system call gate */

#define        LUCODEBIG_SEL        5        /* User code with executable stack */

#define        LBSDICALLS_SEL        16        /* BSDI system call gate */

#define        NLDT                17

#endif /* _I386_SEGMENTS_H_ */