1 files changed, 39 insertions, 5 deletions

diff --git a/mm/swap.h b/mm/swap.h
index baa1fa946b34..ad2f121de970 100644
--- a/mm/swap.h
+++ b/mm/swap.h
@@ -59,7 +59,7 @@ void __delete_from_swap_cache(struct folio *folio,
 void delete_from_swap_cache(struct folio *folio);
 void clear_shadow_from_swap_cache(int type, unsigned long begin,
 				  unsigned long end);
-void swapcache_clear(struct swap_info_struct *si, swp_entry_t entry);
+void swapcache_clear(struct swap_info_struct *si, swp_entry_t entry, int nr);
 struct folio *swap_cache_get_folio(swp_entry_t entry,
 		struct vm_area_struct *vma, unsigned long addr);
 struct folio *filemap_get_incore_folio(struct address_space *mapping,
@@ -73,13 +73,39 @@ struct folio *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_flags,
 		bool skip_if_exists);
 struct folio *swap_cluster_readahead(swp_entry_t entry, gfp_t flag,
 		struct mempolicy *mpol, pgoff_t ilx);
-struct page *swapin_readahead(swp_entry_t entry, gfp_t flag,
-			      struct vm_fault *vmf);
+struct folio *swapin_readahead(swp_entry_t entry, gfp_t flag,
+		struct vm_fault *vmf);
 
 static inline unsigned int folio_swap_flags(struct folio *folio)
 {
 	return swp_swap_info(folio->swap)->flags;
 }
+
+/*
+ * Return the count of contiguous swap entries that share the same
+ * zeromap status as the starting entry. If is_zeromap is not NULL,
+ * it will return the zeromap status of the starting entry.
+ */
+static inline int swap_zeromap_batch(swp_entry_t entry, int max_nr,
+		bool *is_zeromap)
+{
+	struct swap_info_struct *sis = swp_swap_info(entry);
+	unsigned long start = swp_offset(entry);
+	unsigned long end = start + max_nr;
+	bool first_bit;
+
+	first_bit = test_bit(start, sis->zeromap);
+	if (is_zeromap)
+		*is_zeromap = first_bit;
+
+	if (max_nr <= 1)
+		return max_nr;
+	if (first_bit)
+		return find_next_zero_bit(sis->zeromap, end, start) - start;
+	else
+		return find_next_bit(sis->zeromap, end, start) - start;
+}
+
 #else /* CONFIG_SWAP */
 struct swap_iocb;
 static inline void swap_read_folio(struct folio *folio, struct swap_iocb **plug)
@@ -109,7 +135,7 @@ static inline struct folio *swap_cluster_readahead(swp_entry_t entry,
 	return NULL;
 }
 
-static inline struct page *swapin_readahead(swp_entry_t swp, gfp_t gfp_mask,
+static inline struct folio *swapin_readahead(swp_entry_t swp, gfp_t gfp_mask,
 			struct vm_fault *vmf)
 {
 	return NULL;
@@ -120,7 +146,7 @@ static inline int swap_writepage(struct page *p, struct writeback_control *wbc)
 	return 0;
 }
 
-static inline void swapcache_clear(struct swap_info_struct *si, swp_entry_t entry)
+static inline void swapcache_clear(struct swap_info_struct *si, swp_entry_t entry, int nr)
 {
 }
 
@@ -171,5 +197,13 @@ static inline unsigned int folio_swap_flags(struct folio *folio)
 {
 	return 0;
 }
+
+static inline int swap_zeromap_batch(swp_entry_t entry, int max_nr,
+		bool *has_zeromap)
+{
+	return 0;
+}
+
 #endif /* CONFIG_SWAP */
+
 #endif /* _MM_SWAP_H */