#ifndef MEMORY_H
#define MEMORY_H

#include "types.h"

#define VIRTUAL_HEAP_START ((void *)0x40000000)

#define KERNEL_CODE_SEG 0x08
#define KERNEL_DATA_SEX 0x10
#define USER_CODE_SEG 0x18
#define USER_DATA_SEG 0x20

#define PAGE_SIZE 4096

#define PAGE_PRESENT_FLAG 0x001
#define PAGE_RW_FLAG 0x002

#define KERNEL_MEMORY_FLAGS (PAGE_PRESENT_FLAG | PAGE_RW_FLAG)

typedef char **pd_t;
typedef char *pt_t;

extern void ld_kernel_end;
char *kernel_end;

void memory_init(size_t avail_memory);

void *alloc_page();
void free_page(void *page);
void map_page(void *phys_addr, void *virtual_addr);
void *valloc_page();

void *kmalloc();
void kfree(void *p);

void set_cr3(pd_t *pd);

pd_t *create_pd();

void *sys_sbrk(unsigned int n);

void to_kernel_context();
void to_process_context();

#endif /* MEMORY_H */