[RFC PATCH 13/35] ovl: readd fsync

From: Miklos Szeredi
Date: Thu Apr 12 2018 - 11:22:36 EST


Implement stacked fsync().

Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxxxxx>
---
fs/overlayfs/file.c | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)

diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c
index b98204c1c19c..4417527667ff 100644
--- a/fs/overlayfs/file.c
+++ b/fs/overlayfs/file.c
@@ -222,10 +222,30 @@ static ssize_t ovl_write_iter(struct kiocb *iocb, struct iov_iter *iter)
return ret;
}

+static int ovl_fsync(struct file *file, loff_t start, loff_t end, int datasync)
+{
+ struct fd real;
+ const struct cred *old_cred;
+ int ret;
+
+ ret = ovl_real_file(file, &real);
+ if (ret)
+ return ret;
+
+ old_cred = ovl_override_creds(file_inode(file)->i_sb);
+ ret = vfs_fsync_range(real.file, start, end, datasync);
+ revert_creds(old_cred);
+
+ fdput(real);
+
+ return ret;
+}
+
const struct file_operations ovl_file_operations = {
.open = ovl_open,
.release = ovl_release,
.llseek = ovl_llseek,
.read_iter = ovl_read_iter,
.write_iter = ovl_write_iter,
+ .fsync = ovl_fsync,
};
--
2.14.3