readahead: split ondemand readahead interface into two functions

Split ondemand readahead interface into two functions.  I think this makes it
a little clearer for non-readahead experts (like Rusty).

Internally they both call ondemand_readahead(), but the page argument is
changed to an obvious boolean flag.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c
index 0a872a09fed..3ab01c04e00 100644
--- a/fs/ext4/dir.c
+++ b/fs/ext4/dir.c
@@ -138,10 +138,10 @@ static int ext4_readdir(struct file * filp,
                         pgoff_t index = map_bh.b_blocknr >>
                                         (PAGE_CACHE_SHIFT - inode->i_blkbits);
                         if (!ra_has_index(&filp->f_ra, index))
-                                page_cache_readahead_ondemand(
+                                page_cache_sync_readahead(
                                         sb->s_bdev->bd_inode->i_mapping,
                                         &filp->f_ra, filp,
-                                        NULL, index, 1);
+                                        index, 1);
                         filp->f_ra.prev_index = index;
                         bh = ext4_bread(NULL, inode, blk, 0, &err);
                 }