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author | Alex AUVOLAT <alex.auvolat@ens.fr> | 2014-03-28 09:44:01 +0100 |
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committer | Alex AUVOLAT <alex.auvolat@ens.fr> | 2014-03-28 09:44:01 +0100 |
commit | bdce62a91076aa1a076d484ce1d8564a8ba0988f (patch) | |
tree | 27fae66616a07caaa18fbbf7ce1c39d91fea6d29 /sos-code-article6/hwcore/segment.h | |
parent | b5dc9d799f8eca793a4fd1d9b5111155ae6af6d8 (diff) | |
download | SOS-bdce62a91076aa1a076d484ce1d8564a8ba0988f.tar.gz SOS-bdce62a91076aa1a076d484ce1d8564a8ba0988f.zip |
Import article 5, does not compile.
Diffstat (limited to 'sos-code-article6/hwcore/segment.h')
-rw-r--r-- | sos-code-article6/hwcore/segment.h | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/sos-code-article6/hwcore/segment.h b/sos-code-article6/hwcore/segment.h new file mode 100644 index 0000000..4487216 --- /dev/null +++ b/sos-code-article6/hwcore/segment.h @@ -0,0 +1,70 @@ +/* Copyright (C) 2004 The SOS Team + + 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_HWSEGS_H_ +#define _SOS_HWSEGS_H_ + +/** + * @file segments.h + * + * Global and local (GDT/LDT) segment descriptor definition and + * structure. These segments map virtual addresses (ie + * data/instruction addresses, relative to these segment descriptors) + * to linear addresses (ie addresses in the paged-memory space). + * + * @see Intel x86 doc, vol 3 chapter 3. + */ + + +/* + * Global segment selectors (GDT) for SOS/x86. + * + * @see gdt.h + */ +#define SOS_SEG_NULL 0 /* NULL segment, unused by the procesor */ +#define SOS_SEG_KCODE 1 /* Kernel code segment */ +#define SOS_SEG_KDATA 2 /* Kernel data segment */ + + +#ifndef ASM_SOURCE +/** + * Helper macro that builds a segment register's value + */ +#define SOS_BUILD_SEGMENT_REG_VALUE(desc_privilege,in_ldt,seg_index) \ + ( (((desc_privilege) & 0x3) << 0) \ + | (((in_ldt)?1:0) << 2) \ + | ((seg_index) << 3) ) +#else +/* + * Assembler-compliant version. + * + * Caution: In assembler code, "in_ldt" MUST be either 1 or 0, nothing + * else. + */ +#define SOS_BUILD_SEGMENT_REG_VALUE(desc_privilege,in_ldt,seg_index) \ + ( (((desc_privilege) & 0x3) << 0) \ + | ((in_ldt & 1) << 2) \ + | ((seg_index) << 3) ) +#endif + + +/* + * Local segment selectors (LDT) for SOS/x86 + */ +/* None */ + +#endif /* _SOS_HWSEGS_H_ */ |