sys/cpu/amd64/include/segments.h

   1 /*-
   2  * Copyright (c) 1989, 1990 William F. Jolitz
   3  * Copyright (c) 1990 The Regents of the University of California.
   4  * All rights reserved.
   5  *
   6  * This code is derived from software contributed to Berkeley by
   7  * William Jolitz.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  *      from: @(#)segments.h    7.1 (Berkeley) 5/9/91
  34  * $FreeBSD: src/sys/amd64/include/segments.h,v 1.39 2007/03/30 00:06:21 jkim Exp $
  35  * $DragonFly $
  36  */
  37
  38 #ifndef _MACHINE_SEGMENTS_H_
  39 #define _MACHINE_SEGMENTS_H_
  40
  41 /*
  42  * AMD64 Segmentation Data Structures and definitions
  43  */
  44
  45 /*
  46  * Selectors
  47  */
  48
  49 #define SEL_RPL_MASK    3       /* requester priv level */
  50 #define ISPL(s) ((s)&3)         /* what is the priority level of a selector */
  51 #define SEL_KPL 0               /* kernel priority level */
  52 #define SEL_UPL 3               /* user priority level */
  53 #define ISLDT(s)        ((s)&SEL_LDT)   /* is it local or global */
  54 #define SEL_LDT 4               /* local descriptor table */
  55 #define IDXSEL(s)       (((s)>>3) & 0x1fff)             /* index of selector */
  56 #define LSEL(s,r)       (((s)<<3) | SEL_LDT | r)        /* a local selector */
  57 #define GSEL(s,r)       (((s)<<3) | r)                  /* a global selector */
  58
  59 /*
  60  * User segment descriptors (%cs, %ds etc for compatability apps. 64 bit wide)
  61  * For long-mode apps, %cs only has the conforming bit in sd_type, the sd_dpl,
  62  * sd_p, sd_l and sd_def32 which must be zero).  %ds only has sd_p.
  63  */
  64 struct  user_segment_descriptor {
  65         u_int64_t sd_lolimit:16;        /* segment extent (lsb) */
  66         u_int64_t sd_lobase:24;         /* segment base address (lsb) */
  67         u_int64_t sd_type:5;            /* segment type */
  68         u_int64_t sd_dpl:2;             /* segment descriptor priority level */
  69         u_int64_t sd_p:1;               /* segment descriptor present */
  70         u_int64_t sd_hilimit:4;         /* segment extent (msb) */
  71         u_int64_t sd_xx:1;              /* unused */
  72         u_int64_t sd_long:1;            /* long mode (cs only) */
  73         u_int64_t sd_def32:1;           /* default 32 vs 16 bit size */
  74         u_int64_t sd_gran:1;            /* limit granularity (byte/page units)*/
  75         u_int64_t sd_hibase:8;          /* segment base address  (msb) */
  76 } __packed;
  77
  78 /*
  79  * System segment descriptors (128 bit wide)
  80  */
  81 struct  system_segment_descriptor {
  82         u_int64_t sd_lolimit:16;        /* segment extent (lsb) */
  83         u_int64_t sd_lobase:24;         /* segment base address (lsb) */
  84         u_int64_t sd_type:5;            /* segment type */
  85         u_int64_t sd_dpl:2;             /* segment descriptor priority level */
  86         u_int64_t sd_p:1;               /* segment descriptor present */
  87         u_int64_t sd_hilimit:4;         /* segment extent (msb) */
  88         u_int64_t sd_xx0:3;             /* unused */
  89         u_int64_t sd_gran:1;            /* limit granularity (byte/page units)*/
  90         u_int64_t sd_hibase:40 __packed;/* segment base address  (msb) */
  91         u_int64_t sd_xx1:8;
  92         u_int64_t sd_mbz:5;             /* MUST be zero */
  93         u_int64_t sd_xx2:19;
  94 } __packed;
  95
  96 /*
  97  * Gate descriptors (e.g. indirect descriptors, trap, interrupt etc. 128 bit)
  98  * Only interrupt and trap gates have gd_ist.
  99  */
 100 struct  gate_descriptor {
 101         u_int64_t gd_looffset:16;       /* gate offset (lsb) */
 102         u_int64_t gd_selector:16;       /* gate segment selector */
 103         u_int64_t gd_ist:3;             /* IST table index */
 104         u_int64_t gd_xx:5;              /* unused */
 105         u_int64_t gd_type:5;            /* segment type */
 106         u_int64_t gd_dpl:2;             /* segment descriptor priority level */
 107         u_int64_t gd_p:1;               /* segment descriptor present */
 108         u_int64_t gd_hioffset:48 __packed;      /* gate offset (msb) */
 109         u_int64_t sd_xx1:32;
 110 } __packed;
 111
 112         /* system segments and gate types */
 113 #define SDT_SYSNULL      0      /* system null */
 114 #define SDT_SYSLDT       2      /* system 64 bit local descriptor table */
 115 #define SDT_SYSTSS       9      /* system available 64 bit TSS */
 116 #define SDT_SYSBSY      11      /* system busy 64 bit TSS */
 117 #define SDT_SYSCGT      12      /* system 64 bit call gate */
 118 #define SDT_SYSIGT      14      /* system 64 bit interrupt gate */
 119 #define SDT_SYSTGT      15      /* system 64 bit trap gate */
 120
 121         /* memory segment types */
 122 #define SDT_MEMRO       16      /* memory read only */
 123 #define SDT_MEMROA      17      /* memory read only accessed */
 124 #define SDT_MEMRW       18      /* memory read write */
 125 #define SDT_MEMRWA      19      /* memory read write accessed */
 126 #define SDT_MEMROD      20      /* memory read only expand dwn limit */
 127 #define SDT_MEMRODA     21      /* memory read only expand dwn limit accessed */
 128 #define SDT_MEMRWD      22      /* memory read write expand dwn limit */
 129 #define SDT_MEMRWDA     23      /* memory read write expand dwn limit accessed */
 130 #define SDT_MEME        24      /* memory execute only */
 131 #define SDT_MEMEA       25      /* memory execute only accessed */
 132 #define SDT_MEMER       26      /* memory execute read */
 133 #define SDT_MEMERA      27      /* memory execute read accessed */
 134 #define SDT_MEMEC       28      /* memory execute only conforming */
 135 #define SDT_MEMEAC      29      /* memory execute only accessed conforming */
 136 #define SDT_MEMERC      30      /* memory execute read conforming */
 137 #define SDT_MEMERAC     31      /* memory execute read accessed conforming */
 138
 139 /*
 140  * Software definitions are in this convenient format,
 141  * which are translated into inconvenient segment descriptors
 142  * when needed to be used by the 386 hardware
 143  */
 144
 145 struct  soft_segment_descriptor {
 146         unsigned long ssd_base;         /* segment base address  */
 147         unsigned long ssd_limit;        /* segment extent */
 148         unsigned long ssd_type:5;       /* segment type */
 149         unsigned long ssd_dpl:2;        /* segment descriptor priority level */
 150         unsigned long ssd_p:1;          /* segment descriptor present */
 151         unsigned long ssd_long:1;       /* long mode (for %cs) */
 152         unsigned long ssd_def32:1;      /* default 32 vs 16 bit size */
 153         unsigned long ssd_gran:1;       /* limit granularity (byte/page units)*/
 154 } __packed;
 155
 156 /*
 157  * region descriptors, used to load gdt/idt tables before segments yet exist.
 158  */
 159 struct region_descriptor {
 160         unsigned long rd_limit:16;              /* segment extent */
 161         unsigned long rd_base:64 __packed;      /* base address  */
 162 } __packed;
 163
 164 /*
 165  * Size of IDT table
 166  */
 167 #define NIDT    256             /* 32 reserved, 16 h/w, 0 s/w, linux's 0x80 */
 168 #define NRSVIDT 32              /* reserved entries for cpu exceptions */
 169
 170 /*
 171  * Entries in the Interrupt Descriptor Table (IDT)
 172  */
 173 #define IDT_DE          0       /* #DE: Divide Error */
 174 #define IDT_DB          1       /* #DB: Debug */
 175 #define IDT_NMI         2       /* Nonmaskable External Interrupt */
 176 #define IDT_BP          3       /* #BP: Breakpoint */
 177 #define IDT_OF          4       /* #OF: Overflow */
 178 #define IDT_BR          5       /* #BR: Bound Range Exceeded */
 179 #define IDT_UD          6       /* #UD: Undefined/Invalid Opcode */
 180 #define IDT_NM          7       /* #NM: No Math Coprocessor */
 181 #define IDT_DF          8       /* #DF: Double Fault */
 182 #define IDT_FPUGP       9       /* Coprocessor Segment Overrun */
 183 #define IDT_TS          10      /* #TS: Invalid TSS */
 184 #define IDT_NP          11      /* #NP: Segment Not Present */
 185 #define IDT_SS          12      /* #SS: Stack Segment Fault */
 186 #define IDT_GP          13      /* #GP: General Protection Fault */
 187 #define IDT_PF          14      /* #PF: Page Fault */
 188 #define IDT_MF          16      /* #MF: FPU Floating-Point Error */
 189 #define IDT_AC          17      /* #AC: Alignment Check */
 190 #define IDT_MC          18      /* #MC: Machine Check */
 191 #define IDT_XF          19      /* #XF: SIMD Floating-Point Exception */
 192 #define IDT_IO_INTS     NRSVIDT /* Base of IDT entries for I/O interrupts. */
 193 #define IDT_SYSCALL     0x80    /* System Call Interrupt Vector */
 194
 195 /*
 196  * Entries in the Global Descriptor Table (GDT)
 197  */
 198 #define GNULL_SEL       0       /* Null Descriptor */
 199 #define GCODE_SEL       1       /* Kernel Code Descriptor */
 200 #define GDATA_SEL       2       /* Kernel Data Descriptor */
 201 #define GUCODE32_SEL    3       /* User 32 bit code Descriptor */
 202 #define GUDATA_SEL      4       /* User 32/64 bit Data Descriptor */
 203 #define GUCODE_SEL      5       /* User 64 bit Code Descriptor */
 204 #define GPROC0_SEL      6       /* TSS for entering kernel etc */
 205 /* slot 6 is second half of GPROC0_SEL */
 206 #define GUGS32_SEL      8       /* User 32 bit GS Descriptor */
 207 #define NGDT            9
 208
 209 #ifdef _KERNEL
 210 extern struct user_segment_descriptor gdt[];
 211 extern struct soft_segment_descriptor gdt_segs[];
 212 extern struct gate_descriptor *idt;
 213 extern struct region_descriptor r_gdt, r_idt;
 214
 215 void    lgdt(struct region_descriptor *rdp);
 216 void    sdtossd(struct user_segment_descriptor *sdp,
 217             struct soft_segment_descriptor *ssdp);
 218 void    ssdtosd(struct soft_segment_descriptor *ssdp,
 219             struct user_segment_descriptor *sdp);
 220 void    ssdtosyssd(struct soft_segment_descriptor *ssdp,
 221             struct system_segment_descriptor *sdp);
 222 #endif /* _KERNEL */
 223
 224 #endif /* !_MACHINE_SEGMENTS_H_ */