lkml.org 
[lkml]   [2018]   [May]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 18/39] ovl: add ovl_fsync()
Date
Implement stacked fsync().

Don't sync if lower (noticed by Amir Goldstein).

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
---
fs/overlayfs/file.c | 23 +++++++++++++++++++++++
1 file changed, 23 insertions(+)

diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c
index a7af56861aa5..7b47dce4b072 100644
--- a/fs/overlayfs/file.c
+++ b/fs/overlayfs/file.c
@@ -233,10 +233,33 @@ 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_fdget(file, &real);
+ if (ret)
+ return ret;
+
+ /* Don't sync lower file for fear of receiving EROFS error */
+ if (file_inode(real.file) == ovl_inode_upper(file_inode(file))) {
+ 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
\
 
 \ /
  Last update: 2018-05-29 17:14    [W:0.286 / U:27.776 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site