mm/swap: fix the comment of get_kernel_pages

If no pages were pinned, 0 is returned in fact.  Fix the corresponding
comment.

[[email protected]: s/nr_pages/nr_segs/ also, per David, reflow comment]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Miaohe Lin <[email protected]>
Reviewed-by: David Hildenbrand <[email protected]>
Cc: Alistair Popple <[email protected]>
Cc: David Howells <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Naoya Horiguchi <[email protected]>
Cc: NeilBrown <[email protected]>
Cc: Peter Xu <[email protected]>
Cc: Suren Baghdasaryan <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Oscar Salvador <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

mm/swap.c

@@ -166,10 +166,10 @@ EXPORT_SYMBOL(put_pages_list);
  * @pages:	array that receives pointers to the pages pinned.
  *		Should be at least nr_segs long.
  *
- * Returns number of pages pinned. This may be fewer than the number
- * requested. If nr_pages is 0 or negative, returns 0. If no pages
- * were pinned, returns -errno. Each page returned must be released
- * with a put_page() call when it is finished with.
+ * Returns number of pages pinned. This may be fewer than the number requested.
+ * If nr_segs is 0 or negative, returns 0.  If no pages were pinned, returns 0.
+ * Each page returned must be released with a put_page() call when it is
+ * finished with.
  */
 int get_kernel_pages(const struct kvec *kiov, int nr_segs, int write,
 		struct page **pages)