fs: add sync_inode_metadata

Add a new helper to write out the inode using the writeback code,
that is including the correct dirty bit and list manipulation.  A few
of filesystems already opencode this, and a lot of others should be
using it instead of using write_inode_now which also writes out the
data.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 1 insertions, 5 deletions

diff --git a/fs/libfs.c b/fs/libfs.c
index 62baa0387d6e..2dbf4877d7ef 100644
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -892,10 +892,6 @@ EXPORT_SYMBOL_GPL(generic_fh_to_parent);
  */
 int generic_file_fsync(struct file *file, int datasync)
 {
-        struct writeback_control wbc = {
-                .sync_mode = WB_SYNC_ALL,
-                .nr_to_write = 0, /* metadata-only; caller takes care of data */
-        };
         struct inode *inode = file->f_mapping->host;
         int err;
         int ret;
@@ -906,7 +902,7 @@ int generic_file_fsync(struct file *file, int datasync)
         if (datasync && !(inode->i_state & I_DIRTY_DATASYNC))
                 return ret;
 
-        err = sync_inode(inode, &wbc);
+        err = sync_inode_metadata(inode, 1);
         if (ret == 0)
                 ret = err;
         return ret;