seg.h

Version: - FREEBSD - FREEBSD-13-STABLE - FREEBSD-13-0 - FREEBSD-12-STABLE - FREEBSD-12-0 - FREEBSD-11-STABLE - FREEBSD-11-0 - FREEBSD-10-STABLE - FREEBSD-10-0 - FREEBSD-9-STABLE - FREEBSD-9-0 - FREEBSD-8-STABLE - FREEBSD-8-0 - FREEBSD-7-STABLE - FREEBSD-7-0 - FREEBSD-6-STABLE - FREEBSD-6-0 - FREEBSD-5-STABLE - FREEBSD-5-0 - FREEBSD-4-STABLE - FREEBSD-3-STABLE - FREEBSD22 - l41 - OPENBSD - linux-2.6 - MK84 - PLAN9 - xnu-8792
SearchContext: - none - 3 - 10

    1 /* 
    2  * Mach Operating System
    3  * Copyright (c) 1991,1990 Carnegie Mellon University
    4  * Copyright (c) 1991 IBM Corporation 
    5  * All Rights Reserved.
    6  * 
    7  * Permission to use, copy, modify and distribute this software and its
    8  * documentation is hereby granted, provided that both the copyright
    9  * notice and this permission notice appear in all copies of the
   10  * software, derivative works or modified versions, and any portions
   11  * thereof, and that both notices appear in supporting documentation,
   12  * and that the name IBM not be used in advertising or publicity 
   13  * pertaining to distribution of the software without specific, written
   14  * prior permission.
   15  * 
   16  * CARNEGIE MELLON AND IBM ALLOW FREE USE OF THIS SOFTWARE IN ITS "AS IS"
   17  * CONDITION.  CARNEGIE MELLON AND IBM DISCLAIM ANY LIABILITY OF ANY KIND FOR
   18  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
   19  * 
   20  * Carnegie Mellon requests users of this software to return to
   21  * 
   22  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
   23  *  School of Computer Science
   24  *  Carnegie Mellon University
   25  *  Pittsburgh PA 15213-3890
   26  * 
   27  * any improvements or extensions that they make and grant Carnegie Mellon
   28  * the rights to redistribute these changes.
   29  */
   30 
   31 /*
   32  * HISTORY
   33  * $Log:        seg.h,v $
   34  * Revision 2.8  93/02/04  07:57:09  danner
   35  *      Merge in PS2 support.
   36  *      [92/02/22            dbg@ibm]
   37  * 
   38  * Revision 2.7  92/01/03  20:08:46  dbg
   39  *      Add USER_LDT and USER_FPREGS.  Add defines for selector bits.
   40  *      [91/08/20            dbg]
   41  * 
   42  * Revision 2.6  91/05/14  16:15:59  mrt
   43  *      Correcting copyright
   44  * 
   45  * Revision 2.5  91/05/08  12:41:48  dbg
   46  *      Added USER_TSS for TSS that holds IO permission bitmap.
   47  *      Removed space for descriptors 8..38.
   48  *      Added real_descriptor, real_gate, sel_idx.
   49  *      [91/04/26  14:38:07  dbg]
   50  * 
   51  * Revision 2.4  91/02/05  17:14:28  mrt
   52  *      Changed to new Mach copyright
   53  *      [91/02/01  17:37:46  mrt]
   54  * 
   55  * Revision 2.3  90/08/27  21:58:13  dbg
   56  *      Created, to replace old file with same name.
   57  *      [90/07/25            dbg]
   58  * 
   59  */
   60 
   61 #ifndef _I386_SEG_H_
   62 #define _I386_SEG_H_
   63 
   64 #include <platforms.h>
   65 
   66 /*
   67  * i386 segmentation.
   68  */
   69 
   70 /*
   71  * Real segment descriptor.
   72  */
   73 struct real_descriptor {
   74         unsigned int    limit_low:16,   /* limit 0..15 */
   75                         base_low:16,    /* base  0..15 */
   76                         base_med:8,     /* base  16..23 */
   77                         access:8,       /* access byte */
   78                         limit_high:4,   /* limit 16..19 */
   79                         granularity:4,  /* granularity */
   80                         base_high:8;    /* base 24..31 */
   81 };
   82 
   83 struct real_gate {
   84         unsigned int    offset_low:16,  /* offset 0..15 */
   85                         selector:16,
   86                         word_count:8,
   87                         access:8,
   88                         offset_high:16; /* offset 16..31 */
   89 };
   90 
   91 /*
   92  * We build descriptors and gates in a 'fake' format to let the
   93  * fields be contiguous.  We shuffle them into the real format
   94  * at runtime.
   95  */
   96 struct fake_descriptor {
   97         unsigned int    offset:32;              /* offset */
   98         unsigned int    lim_or_seg:20;          /* limit */
   99                                                 /* or segment, for gate */
  100         unsigned int    size_or_wdct:4;         /* size/granularity */
  101                                                 /* word count, for gate */
  102         unsigned int    access:8;               /* access */
  103 };
  104 
  105 #define SZ_32           0x4                     /* 32-bit segment */
  106 #define SZ_G            0x8                     /* 4K limit field */
  107 
  108 #define ACC_A           0x01                    /* accessed */
  109 #define ACC_TYPE        0x1e                    /* type field: */
  110 
  111 #define ACC_TYPE_SYSTEM 0x00                    /* system descriptors: */
  112 
  113 #define ACC_LDT         0x02                        /* LDT */
  114 #define ACC_CALL_GATE_16 0x04                       /* 16-bit call gate */
  115 #define ACC_TASK_GATE   0x05                        /* task gate */
  116 #define ACC_TSS         0x09                        /* task segment */
  117 #define ACC_CALL_GATE   0x0c                        /* call gate */
  118 #define ACC_INTR_GATE   0x0e                        /* interrupt gate */
  119 #define ACC_TRAP_GATE   0x0f                        /* trap gate */
  120 
  121 #define ACC_TSS_BUSY    0x02                        /* task busy */
  122 
  123 #define ACC_TYPE_USER   0x10                    /* user descriptors */
  124 
  125 #define ACC_DATA        0x10                        /* data */
  126 #define ACC_DATA_W      0x12                        /* data, writable */
  127 #define ACC_DATA_E      0x14                        /* data, expand-down */
  128 #define ACC_DATA_EW     0x16                        /* data, expand-down,
  129                                                              writable */
  130 #define ACC_CODE        0x18                        /* code */
  131 #define ACC_CODE_R      0x1a                        /* code, readable */
  132 #define ACC_CODE_C      0x1c                        /* code, conforming */
  133 #define ACC_CODE_CR     0x1e                        /* code, conforming,
  134                                                        readable */
  135 #define ACC_PL          0x60                    /* access rights: */
  136 #define ACC_PL_K        0x00                    /* kernel access only */
  137 #define ACC_PL_U        0x60                    /* user access */
  138 #define ACC_P           0x80                    /* segment present */
  139 
  140 /*
  141  * Components of a selector
  142  */
  143 #define SEL_LDT         0x04                    /* local selector */
  144 #define SEL_PL          0x03                    /* privilege level: */
  145 #define SEL_PL_K        0x00                        /* kernel selector */
  146 #define SEL_PL_U        0x03                        /* user selector */
  147 
  148 /*
  149  * Convert selector to descriptor table index.
  150  */
  151 #define sel_idx(sel)    ((sel)>>3)
  152 
  153 /*
  154  * User descriptors for MACH - 32-bit flat address space
  155  */
  156 #define USER_SCALL      0x07            /* system call gate */
  157 #define USER_CS         0x17            /* user code segment */
  158 #define USER_DS         0x1f            /* user data segment */
  159 
  160 #define LDTSZ           4
  161 
  162 /*
  163  * Kernel descriptors for MACH - 32-bit flat address space.
  164  */
  165 #define KERNEL_CS       0x08            /* kernel code */
  166 #define KERNEL_DS       0x10            /* kernel data */
  167 #define KERNEL_LDT      0x18            /* master LDT */
  168 #define KERNEL_TSS      0x20            /* master TSS (uniprocessor) */
  169 #define USER_LDT        0x28            /* place for per-thread LDT */
  170 #define USER_TSS        0x30            /* place for per-thread TSS
  171                                            that holds IO bitmap */
  172 #define FPE_CS          0x38            /* floating-point emulator code */
  173 #define USER_FPREGS     0x40            /* user-mode access to saved
  174                                            floating-point registers */
  175 
  176 #ifdef PS2
  177 #define ABIOS_INT_RET   0x48            /* 16 bit return selector for ABIOS */
  178 #define ABIOS_TH_RET    0x50            /* 16 bit return selector for ABIOS */
  179 #define ABIOS_INT_SS    0x58            /* ABIOS interrupt stack selector */
  180 #define ABIOS_TH_SS     0x60            /* ABIOS current stack selector */
  181 #define ABIOS_FIRST_AVAIL_SEL \
  182                         0x68            /* first selector for ABIOS
  183                                            to allocate */
  184 #define GDTSZ           0x300           /* size of gdt table */
  185 #else   /* PS2 */
  186 #define GDTSZ           9
  187 #endif  /* PS2 */
  188 
  189 /*
  190  * Interrupt table is always 256 entries long.
  191  */
  192 #define IDTSZ           256
  193 
  194 /*
  195  * Make_gdt_desc converts a segment base address, limit, access1, and access2
  196  * fields into a gdt descriptor entry.
  197  */
  198 
  199 #define make_gdt_desc(sel, base, limit, acc1, acc2) \
  200     { \
  201         struct real_descriptor *g; \
  202         g = (struct real_descriptor *) (((char *)gdt) + sel); \
  203         g->limit_low = limit & 0xffff; \
  204         g->base_low  = base & 0xffff; \
  205         g->base_med  = (base >> 16) & 0xff; \
  206         g->access    = acc1 | ACC_P; \
  207         g->limit_high= limit >> 16; \
  208         g->granularity = acc2; \
  209         g->base_high = base >> 24; \
  210     }
  211 
  212 #endif  /* _I386_SEG_H_ */

Cache object: 917ca7e4d2051c47030c8b4dfadda917

[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]

This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.

FreeBSD/Linux Kernel Cross Reference sys/i386/seg.h

FreeBSD/Linux Kernel Cross Reference
sys/i386/seg.h