On Sun, Jan 31, 2016 at 04:19:46PM +0300, Konstantin Khlebnikov wrote:
> This fixes some cases of missing atime update for overlayfs.
Problem is it will update atime on lower layer, even if it's explicitly marked
read-only. Which I think is a pretty bad breakage of assumptions.
The following patch updates atime (untested) but only in the upper layer.
Obviously it makes no sense to copy-up due to an atime update.
Thanks,
Miklos
---
fs/overlayfs/inode.c | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -370,6 +370,27 @@ struct inode *ovl_d_select_inode(struct
return d_backing_inode(realpath.dentry);
}
+static int ovl_update_time(struct inode *inode, struct timespec *ts, int flags)
+{
+ struct dentry *alias;
+ struct path upperpath;
+
+ if (!(flags & S_ATIME))
+ return 0;
+
+ alias = d_find_any_alias(inode);
+ if (!alias)
+ return 0;
+
+ ovl_path_upper(alias, &upperpath);
+ if (!upperpath.dentry)
+ return 0;
+
+ touch_atime(&upperpath);
+
+ return 0;
+}
+
static const struct inode_operations ovl_file_inode_operations = {
.setattr = ovl_setattr,
.permission = ovl_permission,
@@ -378,6 +399,7 @@ static const struct inode_operations ovl
.getxattr = ovl_getxattr,
.listxattr = ovl_listxattr,
.removexattr = ovl_removexattr,
+ .update_time = ovl_update_time,
};
static const struct inode_operations ovl_symlink_inode_operations = {
