Nigel
13e9beea79
Folders now are alll lower case Started working on the implementation of the Virtual memory manager. Implemented allocate and free page funtionality for as far as I can atm. Implemented the
52 lines
1.2 KiB
C++
52 lines
1.2 KiB
C++
#include "KernelHeap.h"
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// Size of heap meta data is 5 bytes
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struct heap_block{
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uint8_t Used;
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uint32_t Size;
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}
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uint32_t heap_size;
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heap_block* start ;
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void* malloc(size_t size)
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{
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printf("Received request for %d bytes of memory", size);
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heap_block* current = start;
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// look for a free block
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while(current < start + heap_size)
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{
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if(current->size >= size && current->Used == false )
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{
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// We found a spot
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// Set the spot to in-use
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current->Used = false;
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// return the free address
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// NOTE: added an offset from the initial address to accomodate for
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// meta-data.
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return current + sizeof(heap_block);
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}
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current += current->Size + sizeof(heap_block);
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}
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// If we are here we need more memory so we should
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// probably ask the VMM for more
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// TODO: ask for more memory | Extend kernel heap
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}
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void free(void* addr)
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{
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// clear the free boolean that corresponds to this adddress
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// This should be fairly simple
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heap_block* allocatedBlock = addr - sizeof(heap_block);
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allocate_block->Used = false;
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}
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void initHeap()
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{
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} |