X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=mm%2Ffilemap.c;h=239d36163bbe53fbb2115595e82ed9aef3180b02;hb=9781db7b345b5dfe93787aaaf310c861db7c1ede;hp=df343d1e6345ffb33ef3fa4eacf6c784c0ef8178;hpb=5c0dea0959356d77d985ecfb2911e7a9e23b95e3;p=linux-2.6

diff --git a/mm/filemap.c b/mm/filemap.c
index df343d1e63..239d36163b 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
@@ -576,10 +576,12 @@ EXPORT_SYMBOL(unlock_page);
  */
 void end_page_writeback(struct page *page)
 {
-	if (!TestClearPageReclaim(page) || rotate_reclaimable_page(page)) {
-		if (!test_clear_page_writeback(page))
-			BUG();
-	}
+	if (TestClearPageReclaim(page))
+		rotate_reclaimable_page(page);
+
+	if (!test_clear_page_writeback(page))
+		BUG();
+
 	smp_mb__after_clear_bit();
 	wake_up_page(page, PG_writeback);
 }
@@ -611,7 +613,10 @@ 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 +1543,20 @@ 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,