if (unlikely(!page))
continue;
if (radix_tree_exception(page)) {
- if (radix_tree_exceptional_entry(page))
- goto export;
- /* radix_tree_deref_retry(page) */
- goto restart;
+ if (radix_tree_deref_retry(page))
+ goto restart;
+ /*
+ * Otherwise, we must be storing a swap entry
+ * here as an exceptional entry: so return it
+ * without attempting to raise page count.
+ */
+ goto export;
}
if (!page_cache_get_speculative(page))
goto repeat;
return ret;
}
-/*
- * Lockless lookup of swap entry in radix tree, avoiding refcount on pages.
- */
-static pgoff_t shmem_find_swap(struct address_space *mapping, void *radswap)
-{
- void **slots[PAGEVEC_SIZE];
- pgoff_t indices[PAGEVEC_SIZE];
- unsigned int nr_found;
-
-restart:
- nr_found = 1;
- indices[0] = -1;
- while (nr_found) {
- pgoff_t index = indices[nr_found - 1] + 1;
- unsigned int i;
-
- rcu_read_lock();
- nr_found = radix_tree_gang_lookup_slot(&mapping->page_tree,
- slots, indices, index, PAGEVEC_SIZE);
- for (i = 0; i < nr_found; i++) {
- void *item = radix_tree_deref_slot(slots[i]);
- if (radix_tree_deref_retry(item)) {
- rcu_read_unlock();
- goto restart;
- }
- if (item == radswap) {
- rcu_read_unlock();
- return indices[i];
- }
- }
- rcu_read_unlock();
- cond_resched();
- }
- return -1;
-}
-
/*
* Remove swap entry from radix tree, free the swap and its page cache.
*/
int error;
radswap = swp_to_radix_entry(swap);
- index = shmem_find_swap(mapping, radswap);
+ index = radix_tree_locate_item(&mapping->page_tree, radswap);
if (index == -1)
return 0;