66 lines
2.4 KiB
NASM
66 lines
2.4 KiB
NASM
;=----------------------------------------------------------------------------=;
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; GNU GPL OS/K ;
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; ;
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; Desc: Interrupt Descriptor Table related functions ;
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; ;
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; ;
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; Copyright © 2018-2019 The OS/K Team ;
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; ;
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; This file is part of OS/K. ;
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; ;
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; OS/K is free software: you can redistribute it and/or modify ;
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; it under the terms of the GNU General Public License as published by ;
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; the Free Software Foundation, either version 3 of the License, or ;
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; (at your option) any later version. ;
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; ;
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; OS/K is distributed in the hope that it will be useful, ;
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; but WITHOUT ANY WARRANTY; without even the implied warranty of ;
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; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the ;
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; GNU General Public License for more details. ;
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; ;
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; You should have received a copy of the GNU General Public License ;
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; along with OS/K. If not, see <https://www.gnu.org/licenses/>. ;
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;=----------------------------------------------------------------------------=;
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[BITS 64]
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extern gdtPtr
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global MmLoadGdt
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global MmStoreGdt
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;;
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;; Loads the GDT
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;;
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MmLoadGdt:
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;; Loading the gdt via the gdtPtr pointer
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lgdt [rel gdtPtr]
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;; Reloading the segment registers
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mov ax, si ; data segment
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mov ds, ax
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mov es, ax
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mov fs, ax
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mov gs, ax
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mov ss, ax
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mov cs, di ; code segment
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;; We must far jump because we changed the GDT
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lea rax, [rel .next]
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push rax
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ret
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.next:
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;ltr dx ; the TSS
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ret
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;;
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;; Stores the GDT
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;;
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MmStoreGdt:
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;; Loading the gdt via the gdtPtr pointer
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sgdt [rel gdtPtr]
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ret
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