filemap: Remove add_to_page_cache() and add_to_page_cache_locked()

These functions have no more users, so delete them.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>

Documentation/admin-guide/cgroup-v1/memcg_test.rst

@@ -97,7 +97,7 @@ Under below explanation, we assume CONFIG_MEM_RES_CTRL_SWAP=y.
 =============
 
 	Page Cache is charged at
-	- add_to_page_cache_locked().
+	- filemap_add_folio().
 
 	The logic is very clear. (About migration, see below)
 

include/linux/pagemap.h

@@ -1098,8 +1098,6 @@ size_t fault_in_subpage_writeable(char __user *uaddr, size_t size);
 size_t fault_in_safe_writeable(const char __user *uaddr, size_t size);
 size_t fault_in_readable(const char __user *uaddr, size_t size);
 
-int add_to_page_cache_locked(struct page *page, struct address_space *mapping,
-		pgoff_t index, gfp_t gfp);
 int add_to_page_cache_lru(struct page *page, struct address_space *mapping,
 		pgoff_t index, gfp_t gfp);
 int filemap_add_folio(struct address_space *mapping, struct folio *folio,
@@ -1115,22 +1113,6 @@ bool filemap_release_folio(struct folio *folio, gfp_t gfp);
 loff_t mapping_seek_hole_data(struct address_space *, loff_t start, loff_t end,
 		int whence);
 
-/*
- * Like add_to_page_cache_locked, but used to add newly allocated pages:
- * the page is new, so we can just run __SetPageLocked() against it.
- */
-static inline int add_to_page_cache(struct page *page,
-		struct address_space *mapping, pgoff_t offset, gfp_t gfp_mask)
-{
-	int error;
-
-	__SetPageLocked(page);
-	error = add_to_page_cache_locked(page, mapping, offset, gfp_mask);
-	if (unlikely(error))
-		__ClearPageLocked(page);
-	return error;
-}
-
 /* Must be non-static for BPF error injection */
 int __filemap_add_folio(struct address_space *mapping, struct folio *folio,
 		pgoff_t index, gfp_t gfp, void **shadowp);

mm/filemap.c

@@ -929,26 +929,6 @@ noinline int __filemap_add_folio(struct address_space *mapping,
 }
 ALLOW_ERROR_INJECTION(__filemap_add_folio, ERRNO);
 
-/**
- * add_to_page_cache_locked - add a locked page to the pagecache
- * @page:	page to add
- * @mapping:	the page's address_space
- * @offset:	page index
- * @gfp_mask:	page allocation mode
- *
- * This function is used to add a page to the pagecache. It must be locked.
- * This function does not add the page to the LRU.  The caller must do that.
- *
- * Return: %0 on success, negative error code otherwise.
- */
-int add_to_page_cache_locked(struct page *page, struct address_space *mapping,
-		pgoff_t offset, gfp_t gfp_mask)
-{
-	return __filemap_add_folio(mapping, page_folio(page), offset,
-					  gfp_mask, NULL);
-}
-EXPORT_SYMBOL(add_to_page_cache_locked);
-
 int filemap_add_folio(struct address_space *mapping, struct folio *folio,
 				pgoff_t index, gfp_t gfp)
 {

mm/shmem.c

@@ -693,7 +693,7 @@ static unsigned long shmem_unused_huge_shrink(struct shmem_sb_info *sbinfo,
 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 
 /*
- * Like add_to_page_cache_locked, but error if expected item has gone.
+ * Like filemap_add_folio, but error if expected item has gone.
  */
 static int shmem_add_to_page_cache(struct folio *folio,
 				   struct address_space *mapping,

mm/swap_state.c

@@ -95,7 +95,7 @@ void *get_shadow_from_swap_cache(swp_entry_t entry)
 }
 
 /*
- * add_to_swap_cache resembles add_to_page_cache_locked on swapper_space,
+ * add_to_swap_cache resembles filemap_add_folio on swapper_space,
  * but sets SwapCache flag and private instead of mapping and index.
  */
 int add_to_swap_cache(struct page *page, swp_entry_t entry,