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/*
* Mach Operating System
* Copyright (c) 1991,1990 Carnegie Mellon University
* Copyright (c) 1991 IBM Corporation
* All Rights Reserved.
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation,
* and that the name IBM not be used in advertising or publicity
* pertaining to distribution of the software without specific, written
* prior permission.
*
* CARNEGIE MELLON AND IBM ALLOW FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON AND IBM DISCLAIM ANY LIABILITY OF ANY KIND FOR
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie Mellon
* the rights to redistribute these changes.
*/
#include "cpu.h"
#include "vm_param.h"
/* Initialize the 32-bit kernel code and data segment descriptors
to point to the base of the kernel linear space region. */
gdt_desc_initializer(KERNEL_CS,
kvtolin(0), 0xffffffff,
ACC_PL_K|ACC_CODE_R, SZ_32);
gdt_desc_initializer(KERNEL_DS,
kvtolin(0), 0xffffffff,
ACC_PL_K|ACC_DATA_W, SZ_32);
/* Initialize the 16-bit real-mode code and data segment descriptors. */
gdt_desc_initializer(KERNEL_16_CS,
kvtolin(0), 0xffff,
ACC_PL_K|ACC_CODE_R, SZ_16);
gdt_desc_initializer(KERNEL_16_DS,
kvtolin(0), 0xffff,
ACC_PL_K|ACC_DATA_W, SZ_16);
/* Initialize the linear-space data segment descriptor. */
gdt_desc_initializer(LINEAR_CS,
0, 0xffffffff,
ACC_PL_K|ACC_CODE_R, SZ_32);
gdt_desc_initializer(LINEAR_DS,
0, 0xffffffff,
ACC_PL_K|ACC_DATA_W, SZ_32);
/* Initialize the master LDT and TSS descriptors. */
#ifdef ENABLE_KERNEL_LDT
gdt_desc_initializer(KERNEL_LDT,
kvtolin(&cpu->tables.ldt), sizeof(cpu->tables.ldt)-1,
ACC_PL_K|ACC_LDT, 0);
#endif
#ifdef ENABLE_KERNEL_TSS
gdt_desc_initializer(KERNEL_TSS,
kvtolin(&cpu->tables.tss), sizeof(cpu->tables.tss)-1,
ACC_PL_K|ACC_TSS, 0);
#endif
void cpu_gdt_init(struct cpu *cpu)
{
/* Initialize all the selectors of the GDT. */
#define gdt_sel(name) cpu_gdt_init_##name(cpu);
#include "gdt_sels.h"
#undef gdt_sel
}
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