These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / fs / overlayfs / dir.c

diff --git a/kernel/fs/overlayfs/dir.c b/kernel/fs/overlayfs/dir.c
index 692ceda..a2b1d7c 100644 (file)
--- a/kernel/fs/overlayfs/dir.c
+++ b/kernel/fs/overlayfs/dir.c
@@ -618,7 +618,8 @@ static int ovl_remove_upper(struct dentry *dentry, bool is_dir)
         * sole user of this dentry.  Too tricky...  Just unhash for
         * now.
         */
-       d_drop(dentry);
+       if (!err)
+               d_drop(dentry);
        mutex_unlock(&dir->i_mutex);
 
        return err;
@@ -903,6 +904,13 @@ static int ovl_rename2(struct inode *olddir, struct dentry *old,
        if (!overwrite && new_is_dir && !old_opaque && new_opaque)
                ovl_remove_opaque(newdentry);
 
+       /*
+        * Old dentry now lives in different location. Dentries in
+        * lowerstack are stale. We cannot drop them here because
+        * access to them is lockless. This could be only pure upper
+        * or opaque directory - numlower is zero. Or upper non-dir
+        * entry - its pureness is tracked by flag opaque.
+        */
        if (old_opaque != new_opaque) {
                ovl_dentry_set_opaque(old, new_opaque);
                if (!overwrite)