add_to_page_cache_lru_vec()

2 files changed, 57 insertions, 15 deletions

diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index b61fab5a1317..90f74071d678 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -617,6 +617,11 @@ int add_to_page_cache(struct page *page, struct address_space *mapping,
 		      pgoff_t index, gfp_t gfp_mask);
 int add_to_page_cache_lru(struct page *page, struct address_space *mapping,
 				pgoff_t index, gfp_t gfp_mask);
+int add_to_page_cache_lru_vec(struct address_space *mapping,
+			      struct page **pages,
+			      unsigned nr_pages,
+			      pgoff_t offset, gfp_t gfp_mask);
+
 extern void delete_from_page_cache(struct page *page);
 extern void __delete_from_page_cache(struct page *page, void *shadow);
 int replace_page_cache_page(struct page *old, struct page *new, gfp_t gfp_mask);
diff --git a/mm/filemap.c b/mm/filemap.c
index b82fd3be69ca..37e16bd7b0fd 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1063,16 +1063,26 @@ int add_to_page_cache(struct page *page, struct address_space *mapping,
 }
 EXPORT_SYMBOL(add_to_page_cache);
 
-int add_to_page_cache_lru(struct page *page, struct address_space *mapping,
-				pgoff_t offset, gfp_t gfp_mask)
+int add_to_page_cache_lru_vec(struct address_space *mapping,
+			      struct page **pages,
+			      unsigned nr_pages,
+			      pgoff_t offset, gfp_t gfp_mask)
 {
-	void *shadow = NULL;
-	int ret;
+	void *shadow_stack[8], **shadow = shadow_stack;
+	int i, ret = 0, err = 0, nr_added;
 
-	ret = add_to_page_cache_vec(&page, 1, mapping, offset,
-				    gfp_mask, &shadow);
-	if (unlikely(ret))
-		return ret;
+	if (nr_pages > ARRAY_SIZE(shadow_stack)) {
+		shadow = kmalloc_array(nr_pages, sizeof(void *), gfp_mask);
+		if (!shadow)
+			goto slowpath;
+	}
+
+	for (i = 0; i < nr_pages; i++)
+		VM_BUG_ON_PAGE(PageActive(pages[i]), pages[i]);
+
+	ret = add_to_page_cache_vec(pages, nr_pages, mapping,
+				    offset, gfp_mask, shadow);
+	nr_added = ret > 0 ? ret : 0;
 
 	/*
 	 * The page might have been evicted from cache only recently, in which
@@ -1081,13 +1091,40 @@ int add_to_page_cache_lru(struct page *page, struct address_space *mapping,
 	 * the working set, only to cache data that will get overwritten with
 	 * something else, is a waste of memory.
 	 */
-	if (!(gfp_mask & __GFP_WRITE) &&
-	    shadow && workingset_refault(shadow)) {
-		SetPageActive(page);
-		workingset_activation(page);
-	} else
-		ClearPageActive(page);
-	lru_cache_add(page);
+	for (i = 0; i < nr_added; i++) {
+		struct page *page = pages[i];
+		void *s = shadow[i];
+
+		if (!(gfp_mask & __GFP_WRITE) &&
+		    s && workingset_refault(s)) {
+			SetPageActive(page);
+			workingset_activation(page);
+		}
+		lru_cache_add(page);
+	}
+
+	if (shadow != shadow_stack)
+		kfree(shadow);
+
+	return ret;
+slowpath:
+	for (i = 0; i < nr_pages; i++) {
+		err = add_to_page_cache_lru(pages[i], mapping,
+					    offset + i, gfp_mask);
+		if (err)
+			break;
+	}
+
+	return i ?: err;
+}
+EXPORT_SYMBOL_GPL(add_to_page_cache_lru_vec);
+
+int add_to_page_cache_lru(struct page *page, struct address_space *mapping,
+				pgoff_t offset, gfp_t gfp_mask)
+{
+	int ret = add_to_page_cache_lru_vec(mapping, &page, 1, offset, gfp_mask);
+	if (ret < 0)
+		return ret;
 	return 0;
 }
 EXPORT_SYMBOL_GPL(add_to_page_cache_lru);