1 files changed, 17 insertions, 3 deletions

diff --git a/mm/filemap.c b/mm/filemap.c
index df343d1e6345..07e9d9258b48 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -343,7 +343,7 @@ int sync_page_range(struct inode *inode, struct address_space *mapping,
 EXPORT_SYMBOL(sync_page_range);
 
 /**
- * sync_page_range_nolock
+ * sync_page_range_nolock - write & wait on all pages in the passed range without locking
  * @inode:      target inode
  * @mapping:    target address_space
  * @pos:        beginning offset in pages to write
@@ -611,7 +611,10 @@ int __lock_page_killable(struct page *page)
                                         sync_page_killable, TASK_KILLABLE);
 }
 
-/*
+/**
+ * __lock_page_nosync - get a lock on the page, without calling sync_page()
+ * @page: the page to lock
+ *
  * Variant of lock_page that does not require the caller to hold a reference
  * on the page's mapping.
  */
@@ -1538,9 +1541,20 @@ repeat:
         return page;
 }
 
-/*
+/**
+ * read_cache_page_async - read into page cache, fill it if needed
+ * @mapping:    the page's address_space
+ * @index:      the page index
+ * @filler:     function to perform the read
+ * @data:       destination for read data
+ *
  * Same as read_cache_page, but don't wait for page to become unlocked
  * after submitting it to the filler.
+ *
+ * Read into the page cache. If a page already exists, and PageUptodate() is
+ * not set, try to fill the page but don't wait for it to become unlocked.
+ *
+ * If the page does not get brought uptodate, return -EIO.
  */
 struct page *read_cache_page_async(struct address_space *mapping,
                                 pgoff_t index,