1 files changed, 9 insertions, 0 deletions
diff --git a/mm/swap.h b/mm/swap.h
index fc2f6ade7f80..82023ab93205 100644
--- a/mm/swap.h
+++ b/mm/swap.h
@@ -5,6 +5,7 @@
 struct mempolicy;
 
 #ifdef CONFIG_SWAP
+#include <linux/swapops.h> /* for swp_offset */
 #include <linux/blk_types.h> /* for bio_end_io_t */
 
 /* linux/mm/page_io.c */
@@ -31,6 +32,14 @@ extern struct address_space *swapper_spaces[];
 	(&swapper_spaces[swp_type(entry)][swp_offset(entry) \
 		>> SWAP_ADDRESS_SPACE_SHIFT])
 
+/*
+ * Return the swap device position of the swap entry.
+ */
+static inline loff_t swap_dev_pos(swp_entry_t entry)
+{
+	return ((loff_t)swp_offset(entry)) << PAGE_SHIFT;
+}
+
 void show_swap_cache_info(void);
 bool add_to_swap(struct folio *folio);
 void *get_shadow_from_swap_cache(swp_entry_t entry);