Re: [PATCH v3 1/3] mm: page_ext: add an iteration API for page extensions

From: David Hildenbrand
Date: Fri Mar 07 2025 - 03:11:06 EST



+++ b/mm/page_ext.c
@@ -507,6 +507,19 @@ void __meminit pgdat_page_ext_init(struct pglist_data *pgdat)
#endif
+/**
+ * page_ext_lookup() - Lookup a page extension for a PFN.
+ * @pfn: PFN of the page we're interested in.
+ *
+ * Must be called with RCU read lock taken and @pfn must be valid.
+ *
+ * Return: NULL if no page_ext exists for this page.
+ */
+struct page_ext *page_ext_lookup(unsigned long pfn)
+{
+ return lookup_page_ext(pfn_to_page(pfn));
+}
+
/**
* page_ext_get() - Get the extended information for a page.
* @page: The page we're interested in.

As discussed offline, getting rid of lookup_page_ext() can be done later as a cleanup.

Acked-by: David Hildenbrand <david@xxxxxxxxxx>

--
Cheers,

David / dhildenb