ovl: copy up times
Copy up mtime and ctime to overlay inode after times in real object are
modified. Be careful not to dirty cachelines when not necessary.
This is in preparation for moving overlay functionality out of the VFS.
This patch shouldn't have any observable effect.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c
index f480b1a..4fa756c 100644
--- a/fs/overlayfs/dir.c
+++ b/fs/overlayfs/dir.c
@@ -242,7 +242,7 @@
.newinode = inode,
};
- ovl_dentry_version_inc(dentry->d_parent, false);
+ ovl_dir_modified(dentry->d_parent, false);
ovl_dentry_set_upper_alias(dentry);
if (!hardlink) {
/*
@@ -722,7 +722,7 @@
if (err)
goto out_d_drop;
- ovl_dentry_version_inc(dentry->d_parent, true);
+ ovl_dir_modified(dentry->d_parent, true);
out_d_drop:
d_drop(dentry);
out_dput_upper:
@@ -767,7 +767,7 @@
err = vfs_rmdir(dir, upper);
else
err = vfs_unlink(dir, upper, NULL);
- ovl_dentry_version_inc(dentry->d_parent, ovl_type_origin(dentry));
+ ovl_dir_modified(dentry->d_parent, ovl_type_origin(dentry));
/*
* Keeping this dentry hashed would mean having to release
@@ -797,6 +797,7 @@
int err;
bool locked = false;
const struct cred *old_cred;
+ struct dentry *upperdentry;
bool lower_positive = ovl_lower_positive(dentry);
LIST_HEAD(list);
@@ -832,6 +833,17 @@
drop_nlink(dentry->d_inode);
}
ovl_nlink_end(dentry, locked);
+
+ /*
+ * Copy ctime
+ *
+ * Note: we fail to update ctime if there was no copy-up, only a
+ * whiteout
+ */
+ upperdentry = ovl_dentry_upper(dentry);
+ if (upperdentry)
+ ovl_copyattr(d_inode(upperdentry), d_inode(dentry));
+
out_drop_write:
ovl_drop_write(dentry);
out:
@@ -1138,10 +1150,15 @@
drop_nlink(d_inode(new));
}
- ovl_dentry_version_inc(old->d_parent, ovl_type_origin(old) ||
- (!overwrite && ovl_type_origin(new)));
- ovl_dentry_version_inc(new->d_parent, ovl_type_origin(old) ||
- (d_inode(new) && ovl_type_origin(new)));
+ ovl_dir_modified(old->d_parent, ovl_type_origin(old) ||
+ (!overwrite && ovl_type_origin(new)));
+ ovl_dir_modified(new->d_parent, ovl_type_origin(old) ||
+ (d_inode(new) && ovl_type_origin(new)));
+
+ /* copy ctime: */
+ ovl_copyattr(d_inode(olddentry), d_inode(old));
+ if (d_inode(new) && ovl_dentry_upper(new))
+ ovl_copyattr(d_inode(newdentry), d_inode(new));
out_dput:
dput(newdentry);
diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index ed16a89..0fa48d5 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -304,6 +304,9 @@
}
revert_creds(old_cred);
+ /* copy c/mtime */
+ ovl_copyattr(d_inode(realdentry), inode);
+
out_drop_write:
ovl_drop_write(dentry);
out:
diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index 7538b9b..008420e 100644
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -231,7 +231,7 @@
void ovl_inode_init(struct inode *inode, struct dentry *upperdentry,
struct dentry *lowerdentry);
void ovl_inode_update(struct inode *inode, struct dentry *upperdentry);
-void ovl_dentry_version_inc(struct dentry *dentry, bool impurity);
+void ovl_dir_modified(struct dentry *dentry, bool impurity);
u64 ovl_dentry_version_get(struct dentry *dentry);
bool ovl_is_whiteout(struct dentry *dentry);
struct file *ovl_path_open(struct path *path, int flags);
diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
index 6f10780..30a05d1 100644
--- a/fs/overlayfs/util.c
+++ b/fs/overlayfs/util.c
@@ -333,7 +333,7 @@
}
}
-void ovl_dentry_version_inc(struct dentry *dentry, bool impurity)
+static void ovl_dentry_version_inc(struct dentry *dentry, bool impurity)
{
struct inode *inode = d_inode(dentry);
@@ -348,6 +348,14 @@
OVL_I(inode)->version++;
}
+void ovl_dir_modified(struct dentry *dentry, bool impurity)
+{
+ /* Copy mtime/ctime */
+ ovl_copyattr(d_inode(ovl_dentry_upper(dentry)), d_inode(dentry));
+
+ ovl_dentry_version_inc(dentry, impurity);
+}
+
u64 ovl_dentry_version_get(struct dentry *dentry)
{
struct inode *inode = d_inode(dentry);