const int local_nr_pages = end - start;
                const int page_limit = cur_page + local_nr_pages;
                
-               down_read(¤t->mm->mmap_sem);
-               ret = get_user_pages(current, current->mm, uaddr,
-                                    local_nr_pages,
-                                    write_to_vm, 0, &pages[cur_page], NULL);
-               up_read(¤t->mm->mmap_sem);
-
+               ret = get_user_pages_fast(uaddr, local_nr_pages,
+                               write_to_vm, &pages[cur_page]);
                if (ret < local_nr_pages) {
                        ret = -EFAULT;
                        goto out_unmap;
 
        int nr_pages;
 
        nr_pages = min(dio->total_pages - dio->curr_page, DIO_PAGES);
-       down_read(¤t->mm->mmap_sem);
-       ret = get_user_pages(
-               current,                        /* Task for fault acounting */
-               current->mm,                    /* whose pages? */
+       ret = get_user_pages_fast(
                dio->curr_user_address,         /* Where from? */
                nr_pages,                       /* How many pages? */
                dio->rw == READ,                /* Write to memory? */
-               0,                              /* force (?) */
-               &dio->pages[0],
-               NULL);                          /* vmas */
-       up_read(¤t->mm->mmap_sem);
+               &dio->pages[0]);                /* Put results here */
 
        if (ret < 0 && dio->blocks_available && (dio->rw & WRITE)) {
                struct page *page = ZERO_PAGE(0);