[PATCH] libfs: remove page up-to-date check from simple_readpage

Remove the unnecessary PageUptodate check from simple_readpage.  The only
two callers for ->readpage that don't have explicit PageUptodate check are
read_cache_pages and page_cache_read which operate on newly allocated pages
which don't have the flag set.

[akpm: use the allegedly-faster clear_page(), too]
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/fs/libfs.c b/fs/libfs.c
index 8db5afb..3793aaa 100644 (file)
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -317,17 +317,9 @@ int simple_rename(struct inode *old_dir, struct dentry *old_dentry,
 
 int simple_readpage(struct file *file, struct page *page)
 {
-       void *kaddr;
-
-       if (PageUptodate(page))
-               goto out;
-
-       kaddr = kmap_atomic(page, KM_USER0);
-       memset(kaddr, 0, PAGE_CACHE_SIZE);
-       kunmap_atomic(kaddr, KM_USER0);
+       clear_highpage(page);
        flush_dcache_page(page);
        SetPageUptodate(page);
-out:
        unlock_page(page);
        return 0;
 }