/*- * SPDX-License-Identifier: BSD-3-Clause * * 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. * * from: @(#)segments.h 7.1 (Berkeley) 5/9/91 * $FreeBSD$ */ #ifndef _MACHINE_SEGMENTS_H_ #define _MACHINE_SEGMENTS_H_ /* * 386 Segmentation Data Structures and definitions * William F. Jolitz (william@ernie.berkeley.edu) 6/20/1989 */ #include <x86/segments.h> /* * 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 ssd_base ; /* segment base address */ unsigned ssd_limit ; /* segment extent */ unsigned ssd_type:5 ; /* segment type */ unsigned ssd_dpl:2 ; /* segment descriptor priority level */ unsigned ssd_p:1 ; /* segment descriptor present */ unsigned ssd_xx:4 ; /* unused */ unsigned ssd_xx1:2 ; /* unused */ unsigned ssd_def32:1 ; /* default 32 vs 16 bit size */ unsigned ssd_gran:1 ; /* limit granularity (byte/page units)*/ }; /* * 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 __packed; /* base address */ }; /* * 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 */ /* other bits are affected descriptor index */ #define SEGEX_IDX(s) (((s)>>3)&0x1fff) #ifdef _KERNEL extern int _default_ldt; extern union descriptor *gdt; extern union descriptor *ldt; extern struct soft_segment_descriptor gdt_segs[]; extern struct gate_descriptor *idt; void lgdt(struct region_descriptor *rdp); void sdtossd(struct segment_descriptor *sdp, struct soft_segment_descriptor *ssdp); void ssdtosd(struct soft_segment_descriptor *ssdp, struct segment_descriptor *sdp); #endif /* _KERNEL */ #endif /* !_MACHINE_SEGMENTS_H_ */ |