extracting swap type from page table entry (corrected)

/* checks whether a pte_t is a swap pte, and extracts the swap
 * entry from the pte, and the type from the entry
 */

#include <linux/swapops.h>

unsigned pte_to_type(pte_t mypte){
    swp_entry_t myentry;
    unsigned mytype;

    if is_swap_pte(mypte)
    {
        myentry = pte_to_swp_entry(mypte);
        mytype = swp_type(myentry);
        return mytype;
    }
    return -1;
}