Commit ec848215 authored Apr 01, 2020 by Matthew Wilcox (Oracle) Committed by Linus Torvalds Apr 02, 2020

include/linux/pagemap.h: rename arguments to find_subpage

This isn't just a random struct page, it's known to be a head page, and
calling it head makes the function better self-documenting. The pgoff_t
is less confusing if it's named index instead of offset. Also add a
couple of comments to explain why we're doing various things.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20200318140253.6141-3-willy@infradead.org

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent e520e932

include/linux/pagemap.h

+10 −5

Original line number	Diff line number	Diff line
		@@ -333,14 +333,19 @@ static inline struct page grab_cache_page_nowait(struct address_space mapping,
		mapping_gfp_mask(mapping));
		}

		static inline struct page find_subpage(struct page page, pgoff_t offset)
		/*
		* Given the page we found in the page cache, return the page corresponding
		* to this index in the file
		*/
		static inline struct page find_subpage(struct page head, pgoff_t index)
		{
		if (PageHuge(page))
		return page;
		/* HugeTLBfs wants the head page regardless */
		if (PageHuge(head))
		return head;

		VM_BUG_ON_PAGE(PageTail(page), page);
		VM_BUG_ON_PAGE(PageTail(head), head);

		return page + (offset & (compound_nr(page) - 1));
		return head + (index & (compound_nr(head) - 1));
		}

		struct page find_get_entry(struct address_space mapping, pgoff_t offset);