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#include <kernel/paging.h>

uint32_t pageDirectory[1024] __attribute__((aligned(4096)));
uint32_t* pageTable_ID[1024] __attribute__ ((aligned(4096)));
uint32_t* pageTable_Kernel[1024] __attribute__ ((aligned(4096)));

extern void pagingLoadDir(uint32_t* directory);
extern void pagingEnable();

void pagingCalculateAddress(uint32_t vaddr, uint16_t* dirEntry, uint16_t* tableEntry) {
   *dirEntry = vaddr / 4194304;
   *tableEntry = vaddr % 4194304;
}

void pagingFillTable(void* table, uint32_t* address, uint16_t attributes) {
   uint32_t* tablePtr = (uint32_t*) table;
   for(uint16_t i = 0; i < 1024; i++) {
      tablePtr[i] = address;
      tablePtr[i] |= attributes;
      address += 4096;
   }
}

void pagingAddTable(uint16_t entry, void* table, uint16_t attributes) {
   pageDirectory[entry] = table;
   pageDirectory[entry] |= attributes;
}

void pagingInit(void) {
   for(uint16_t i = 0; i < 1024; i++) pageDirectory[i] = 0;
   
   pagingFillTable(pageTable_ID, 0x00000000, 3);
   pagingAddTable(0, pageTable_ID, 3);
   pagingFillTable(pageTable_Kernel, 0x00100000, 3);
   pagingAddTable(768, pageTable_Kernel, 3);
   
   pagingLoadDir((uint32_t) pageDirectory);
   pagingEnable();
}

void pagingFillTable(..., uint32_t* address, ...) {
   ...
   for(...) {
      ...
      address += 4096;
   }
}