Commit a6de4b48 authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle) Committed by Linus Torvalds
Browse files

mm: convert find_get_entry to return the head page 

There are only four callers remaining of find_get_entry().
get_shadow_from_swap_cache() only wants to see shadow entries and doesn't
care about which page is returned.  Push the find_subpage() call into
find_lock_entry(), find_get_incore_page() and pagecache_get_page().

[willy@infradead.org: fix oops]
  Link: https://lkml.kernel.org/r/20200914112738.GM6583@casper.infradead.org



Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: William Kucharski <william.kucharski@oracle.com>
Link: https://lkml.kernel.org/r/20200910183318.20139-7-willy@infradead.org


Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 9dfc8ff3

mm/filemap.c

+7 −6
Original line number Diff line number Diff line
@@ -1645,19 +1645,19 @@ EXPORT_SYMBOL(page_cache_prev_miss); 
/**

 * find_get_entry - find and get a page cache entry

 * @mapping: the address_space to search

 * @offset: the page cache index

 * @index: The page cache index.

 *

 * Looks up the page cache slot at @mapping & @offset.  If there is a

 * page cache page, it is returned with an increased refcount.

 * page cache page, the head page is returned with an increased refcount.

 *

 * If the slot holds a shadow entry of a previously evicted page, or a

 * swap entry from shmem/tmpfs, it is returned.

 *

 * Return: the found page or shadow entry, %NULL if nothing is found.

 * Return: The head page or shadow entry, %NULL if nothing is found.

 */

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

struct page *find_get_entry(struct address_space *mapping, pgoff_t index)

{

	XA_STATE(xas, &mapping->i_pages, offset);

	XA_STATE(xas, &mapping->i_pages, index);

	struct page *page;



	rcu_read_lock();
@@ -1685,7 +1685,6 @@ repeat: 
		put_page(page);

		goto repeat;

	}

	page = find_subpage(page, offset);

out:

	rcu_read_unlock();
@@ -1722,6 +1721,7 @@ repeat: 
			put_page(page);

			goto repeat;

		}

		page = find_subpage(page, offset);

		VM_BUG_ON_PAGE(page_to_pgoff(page) != offset, page);

	}

	return page;
@@ -1768,6 +1768,7 @@ repeat: 
		page = NULL;

	if (!page)

		goto no_page;

	page = find_subpage(page, index);



	if (fgp_flags & FGP_LOCK) {

		if (fgp_flags & FGP_NOWAIT) {

mm/swap_state.c

+3 −1
Original line number Diff line number Diff line
@@ -431,8 +431,10 @@ struct page *find_get_incore_page(struct address_space *mapping, pgoff_t index) 
	struct swap_info_struct *si;

	struct page *page = find_get_entry(mapping, index);



	if (!xa_is_value(page))

	if (!page)

		return page;

	if (!xa_is_value(page))

		return find_subpage(page, index);

	if (!shmem_mapping(mapping))

		return NULL;

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