pass writeback_control to ->write_inode

This gives the filesystem more information about the writeback that
is happening.  Trond requested this for the NFS unstable write handling,
and other filesystems might benefit from this too by beeing able to
distinguish between the different callers in more detail.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/hfs/inode.c b/fs/hfs/inode.c
index a1cbff2..14f5cb1 100644
--- a/fs/hfs/inode.c
+++ b/fs/hfs/inode.c
@@ -381,7 +381,7 @@
 					 HFS_SB(inode->i_sb)->alloc_blksz);
 }
 
-int hfs_write_inode(struct inode *inode, int unused)
+int hfs_write_inode(struct inode *inode, struct writeback_control *wbc)
 {
 	struct inode *main_inode = inode;
 	struct hfs_find_data fd;