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authorThomas Bushnell <thomas@gnu.org>1997-02-25 21:28:37 +0000
committerThomas Bushnell <thomas@gnu.org>1997-02-25 21:28:37 +0000
commitf07a4c844da9f0ecae5bbee1ab94be56505f26f7 (patch)
tree12b07c7e578fc1a5f53dbfde2632408491ff2a70 /i386/util/gdt.h
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+/*
+ * 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 <mach/machine/seg.h>
+
+/*
+ * 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_