ngiddings
961139df9e
Moved base linear address to 0xFF800000 Kernel only reserves the page frames it actually needs Memory for multiboot2 headers is freed Video memory and APIC registers are dynamically mapped into linear addresses
76 lines
1.6 KiB
C
76 lines
1.6 KiB
C
#pragma once
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#include "memorymap.h"
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#include "types/physaddr.h"
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#include <stddef.h>
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/**
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* @brief Describes a stack containing the physical addresses of available page
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* frames.
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*
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*/
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struct page_stack_t
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{
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/**
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* @brief The total number of physical pages managed by the system.
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*
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*/
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size_t total_pages;
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/**
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* @brief Points to the topmost physical address on the stack.
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*
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*/
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physaddr_t *stack_pointer;
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/**
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* @brief Points to the bottom of the stack.
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*
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*/
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physaddr_t *base_pointer;
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/**
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* @brief Points to the limit of the stack. The stack cannot grow beyond
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* this point.
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*
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*/
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physaddr_t *limit_pointer;
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};
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/**
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* @brief Pop the topmost address from the stack and returns that value.
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*
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* If the stack is empty, this function will instead return a status code. This
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* can be identified by testing the least signifigant bits of the return value.
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*
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* @param stack
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* @return physaddr_t
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*/
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physaddr_t reserve_page(struct page_stack_t *stack);
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/**
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* @brief Pushes `location` onto the stack.
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*
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* If there is no room on the stack, the stack will be unaffected.
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*
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* @param stack
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* @param location
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*/
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int free_page(struct page_stack_t *stack, physaddr_t location);
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/**
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* @brief Computes the number of available pages.
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*
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* @param stack
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* @return size_t
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*/
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size_t free_page_count(struct page_stack_t *stack);
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/**
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* @brief Push all available pages in `map` onto the stack
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*
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* @param stack
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* @param map
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*/
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int initialize_page_stack(struct page_stack_t *stack, struct memory_map_t *map);
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