Алгоритм вычисления страницы

#define PAGESIZE 4096
#define BLOCKSIZE 262144 //64 * 4096;

uint32_t startpage, endpage, pages;
uint32_t page, block, page_chunk;
uint32_t block_idx, page_idx, uart_byte_idx, page_addr;
uint32_t row_address;
uint32_t last_chunk;
uint32_t total_sent_size;
void GetLoggerDataFast(uint32_t offset, uint32_t datasize)
{
    total_sent_size = 0;
    
    last_chunk = datasize % PAGESIZE;
    
    pages = (datasize / PAGESIZE);
    
    if (pages == 0)
        pages = 1;
    else
    {
        if(last_chunk)
            pages++;
    }

    startpage = (offset % BLOCKSIZE) / PAGESIZE;
    endpage = ((offset + datasize) % BLOCKSIZE) / PAGESIZE;
    
    page = startpage;
    
    for (page_idx = 0; page_idx < pages; page_idx++)
    { 
        
    if (page_idx == 0)  
    {
        if (datasize > PAGESIZE)
        {
            page_chunk = PAGESIZE - (offset % PAGESIZE);
            page_addr = (offset % PAGESIZE);
        }
        else
        {
            page_chunk = datasize;
            page_addr = 0;
        }
    }
    else if (page_idx  == ( pages-1)) 
    {
        page_chunk = datasize - ((pages-1) * PAGESIZE);
             //page_chunk = datasize - total_sent_size;
        page_addr = 0;
    }
    else
    {
        page_chunk = PAGESIZE;
        page_addr = 0;
    }
        
        printf ("page num = %d \n", page);
        printf ("page addr = %d \n", page_addr);
        printf ("page chunk = %d \n", page_chunk);
        printf ("-------------------\n");
        
        total_sent_size += page_chunk;
         
        page++;
        if (page > 63)
        {
            page = 0;
        }
    } 
    
     printf ("total size = %d \n", total_sent_size);
     printf ("\n\n");
}