kalloc.h

/*
 * Very simple memory allocator
 */
 
#pragma once
 
#include "types.h"
#include "memory.h"
 
class Kalloc
{
    private:
        const mword begin;
        mword end;
 
        // Bitmap for 64 MB of memory
        static const unsigned mempool_pages = 64*(1<<20)/PAGE_SIZE;
        unsigned page_bitmap[mempool_pages/32];
 
        bool is_page_allocated(unsigned idx);
        void mark_page_allocated(unsigned idx, bool allocated);
 
    public:
 
        enum Fill
        {
            NOFILL = 0,
            FILL_0,
            FILL_1
        };
 
        static Kalloc allocator;
 
        Kalloc (mword virt_begin, mword virt_end) : begin (virt_begin), end (virt_end) {}
 
        void * alloc(unsigned size);
 
        void * alloc_page (unsigned count, Fill fill = NOFILL);
        void free_page (void *);

        static void * phys2virt (mword);

        static mword virt2phys (void *);
};