From f07a4c844da9f0ecae5bbee1ab94be56505f26f7 Mon Sep 17 00:00:00 2001 From: Thomas Bushnell Date: Tue, 25 Feb 1997 21:28:37 +0000 Subject: Initial source --- i386/util/gdt.h | 88 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 88 insertions(+) create mode 100644 i386/util/gdt.h (limited to 'i386/util/gdt.h') diff --git a/i386/util/gdt.h b/i386/util/gdt.h new file mode 100644 index 0000000..5b422ae --- /dev/null +++ b/i386/util/gdt.h @@ -0,0 +1,88 @@ +/* + * Copyright (c) 1995-1994 The University of Utah and + * the Computer Systems Laboratory at the University of Utah (CSL). + * All rights reserved. + * + * Permission to use, copy, modify and distribute this software is hereby + * granted provided that (1) source code retains these copyright, permission, + * and disclaimer notices, and (2) redistributions including binaries + * reproduce the notices in supporting documentation, and (3) all advertising + * materials mentioning features or use of this software display the following + * acknowledgement: ``This product includes software developed by the + * Computer Systems Laboratory at the University of Utah.'' + * + * THE UNIVERSITY OF UTAH AND CSL ALLOW FREE USE OF THIS SOFTWARE IN ITS "AS + * IS" CONDITION. THE UNIVERSITY OF UTAH AND CSL DISCLAIM ANY LIABILITY OF + * ANY KIND FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. + * + * CSL requests users of this software to return to csl-dist@cs.utah.edu any + * improvements that they make and grant CSL redistribution rights. + * + * Author: Bryan Ford, University of Utah CSL + */ +#ifndef _I386_GDT_ +#define _I386_GDT_ + +#include + +/* + * Collect and define the GDT segment selectors. + * xxx_IDX is the index number of the selector; + * xxx is the actual selector value (index * 8). + */ +enum gdt_idx +{ + GDT_NULL_IDX = 0, + +#define gdt_sel(name) name##_IDX, +#include "gdt_sels.h" +#undef gdt_sel + + GDT_FIRST_FREE_IDX +}; + +enum gdt_sel +{ + GDT_NULL = 0, + +#define gdt_sel(name) name = name##_IDX * 8, +#include "gdt_sels.h" +#undef gdt_sel +}; + +#define GDTSZ GDT_FIRST_FREE_IDX + + +/* If we have a KERNEL_TSS, use that as our DEFAULT_TSS if none is defined yet. + (The DEFAULT_TSS gets loaded by cpu_tables_load() upon switching to pmode.) + Similarly with DEFAULT_LDT. */ +#if defined(ENABLE_KERNEL_TSS) && !defined(DEFAULT_TSS) +#define DEFAULT_TSS KERNEL_TSS +#define DEFAULT_TSS_IDX KERNEL_TSS_IDX +#endif +#if defined(ENABLE_KERNEL_LDT) && !defined(DEFAULT_LDT) +#define DEFAULT_LDT KERNEL_LDT +#define DEFAULT_LDT_IDX KERNEL_LDT_IDX +#endif + + +/* Fill a segment descriptor in a CPU's GDT. */ +#define fill_gdt_descriptor(cpu, segment, base, limit, access, sizebits) \ + fill_descriptor(&(cpu)->tables.gdt[segment/8], \ + base, limit, access, sizebits) + +#define i16_fill_gdt_descriptor(cpu, segment, base, limit, access, sizebits) \ + i16_fill_descriptor(&(cpu)->tables.gdt[segment/8], \ + base, limit, access, sizebits) + + +/* This automatically defines GDT descriptor initialization functions. */ +#define gdt_desc_initializer(segment, base, limit, access, sizebits) \ + void cpu_gdt_init_##segment(struct cpu *cpu) \ + { \ + fill_gdt_descriptor(cpu, segment, base, limit, \ + access, sizebits); \ + } + + +#endif _I386_GDT_ -- cgit v1.2.3