On Thu, May 07, 2020 at 03:50:56PM +0800, Zhen Lei wrote:
> @@ -266,7 +266,7 @@ int swap_writepage(struct page *page, struct writeback_control *wbc)
>
> static sector_t swap_page_sector(struct page *page)
> {
> - return (sector_t)__page_file_index(page) << (PAGE_SHIFT - 9);
> + return npage_to_sectors((sector_t)__page_file_index(page));
If you make npage_to_sectors() a proper function instead of a macro,
you can do the casting inside the function instead of in the callers
(which is prone to bugs).
Also, this is a great example of why page_to_sector() was a better name
than npage_to_sectors(). This function doesn't return a count of sectors,
it returns a sector number within the swap device.
