Import and compile code for article 6.5

1 files changed, 42 insertions, 0 deletions

diff --git a/sos-code-article6.5/hwcore/gdt.h b/sos-code-article6.5/hwcore/gdt.h
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+/* Copyright (C) 2004  David Decotigny
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License
+   as published by the Free Software Foundation; either version 2
+   of the License, or (at your option) any later version.
+   
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+   
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
+   USA. 
+*/
+#ifndef _SOS_GDT_H_
+#define _SOS_GDT_H_
+
+/**
+ * @file gdt.h
+ *
+ * The routines that manage the GDT, the table that maps the virtual
+ * addresses (data/instructions, segment-relative), to "linear"
+ * addresses (ie paged-memory). In SOS/x86, we use a "flat" virtual
+ * space, ie the virtual and linear spaces are equivalent.
+ *
+ * @see Intel x86 doc vol 3, chapter 3
+ */
+
+#include <sos/types.h>
+#include <sos/errno.h>
+
+/**
+ * Configure the virtual space as a direct mapping to the linear
+ * address space (ie "flat" virtual space).
+ */
+sos_ret_t sos_gdt_subsystem_setup(void);
+
+
+#endif /* _SOS_GDT_H_ */