Man page 9 : find_lock_page

find_lock_page - locate, pin and lock a pagecache page

struct page * find_lock_page(struct address_space *  mapping , pgoff_t  offset );

mapping
    the address_space to search

offset
    the page index

Locates the desired pagecache page, locks it, increments its reference count and returns its address.

Returns zero if the page was not present. find_lock_page may sleep.