redonkable
/
remarkable-linux
1
0
Fork 0
Code Releases Activity

ovl: fix failure to fsync lower dir 

commit d796e77f1d upstream.

As a writable mount, it is not expected for overlayfs to return
EINVAL/EROFS for fsync, even if dir/file is not changed.

This commit fixes the case of fsync of directory, which is easier to
address, because overlayfs already implements fsync file operation for
directories.

The problem reported by Raphael is that new PostgreSQL 10.0 with a
database in overlayfs where lower layer in squashfs fails to start.
The failure is due to fsync error, when PostgreSQL does fsync on all
existing db directories on startup and a specific directory exists
lower layer with no changes.

Reported-by: Raphael Hertzog <raphael@ouaza.com>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Tested-by: Raphaël Hertzog <hertzog@debian.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
steinar/wifi_calib_4_9_kernel
Amir Goldstein 2017-11-08 09:39:46 +02:00 committed by Greg Kroah-Hartman
parent a468a3749b
commit 38e3bc59e0
1 changed files with 5 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
fs/overlayfs/readdir.c
View File

@ -434,10 +434,14 @@ static int ovl_dir_fsync(struct file *file, loff_t start, loff_t end,
struct dentry *dentry = file->f_path.dentry;
struct file *realfile = od->realfile;
/* Nothing to sync for lower */
if (!OVL_TYPE_UPPER(ovl_path_type(dentry)))
return 0;
/*
* Need to check if we started out being a lower dir, but got copied up
*/
if (!od->is_upper && OVL_TYPE_UPPER(ovl_path_type(dentry))) {
if (!od->is_upper) {
struct inode *inode = file_inode(file);
realfile = lockless_dereference(od->upperfile);