[PATCH] unlock_page when get_swap_bio fails

Patch from Hugh Dickins <hugh@veritas.com>

swap_readpage and swap_writepage forgot
to unlock_page if get_swap_bio failed.

mm/page_io.c

@@ -97,6 +97,7 @@ int swap_writepage(struct page *page)
 	bio = get_swap_bio(GFP_NOIO, page, end_swap_bio_write);
 	if (bio == NULL) {
 		set_page_dirty(page);
+		unlock_page(page);
 		ret = -ENOMEM;
 		goto out;
 	}
@@ -116,6 +117,7 @@ int swap_readpage(struct file *file, struct page *page)
 	ClearPageUptodate(page);
 	bio = get_swap_bio(GFP_KERNEL, page, end_swap_bio_read);
 	if (bio == NULL) {
+		unlock_page(page);
 		ret = -ENOMEM;
 		goto out;
 	}