On 3/23/19 11:04 PM, Matthew Wilcox wrote:
> The patch for you should have looked like this:
>
> @@ -335,11 +335,12 @@ static inline struct page *grab_cache_page_nowait(struct address_space *mapping,
>
> static inline struct page *find_subpage(struct page *page, pgoff_t offset)
> {
> + unsigned long index = page_index(page);
> +
> VM_BUG_ON_PAGE(PageTail(page), page);
> - VM_BUG_ON_PAGE(page->index > offset, page);
> - VM_BUG_ON_PAGE(page->index + (1 << compound_order(page)) <= offset,
> - page);
> - return page - page->index + offset;
> + VM_BUG_ON_PAGE(index > offset, page);
> + VM_BUG_ON_PAGE(index + (1 << compound_order(page)) <= offset, page);
> + return page - index + offset;
> }
It works great.
