49 lines
1.3 KiB
NASM
49 lines
1.3 KiB
NASM
; Calcite, src/kernel/paging.asm
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; Copyright 2025 Benji Dial
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;
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; This program 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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; This program is distributed in the hope that it will be useful, but
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; WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
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; or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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; for more details.
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;
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; You should have received a copy of the GNU General Public License along
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; with this program. If not, see <https://www.gnu.org/licenses/>.
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bits 64
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default rel
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;both defined in paging.c
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extern kernel_p4_physical_address
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extern init_stack
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init_stack_length equ 16384
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section .text
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;referenced in paging.c
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extern invlpg
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invlpg:
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invlpg byte [rdi]
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ret
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extern switch_to_kernel_page_tables
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switch_to_kernel_page_tables:
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;switch the page table
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mov rax, qword [kernel_p4_physical_address]
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mov cr3, rax
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;set the stack
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mov rsp, init_stack + init_stack_length
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;push 0 before jumping to continuation so that if the continuation
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;does return (which it shouldn't), it returns to null instead of
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;popping garbage and returning there
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push qword 0
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jmp rdi
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