[PATCH 07/12] ovl: narrow locking in ovl_rename()

[NeilBrown <neil@brown.name>]

Drop the rename lock immediately after the rename, and use
ovl_cleanup_unlocked() for cleanup.

This makes way for future changes where locks are taken on individual
dentries rather than the whole directory.

Signed-off-by: NeilBrown <neil@brown.name>
---
 fs/overlayfs/dir.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c
index 2b879d7c386e..5afe17cee305 100644
--- a/fs/overlayfs/dir.c
+++ b/fs/overlayfs/dir.c
@@ -1270,9 +1270,10 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir,
 			    new_upperdir, newdentry, flags);
 	if (err)
 		goto out_dput;
+	unlock_rename(new_upperdir, old_upperdir);
 
 	if (cleanup_whiteout)
-		ovl_cleanup(ofs, old_upperdir->d_inode, newdentry);
+		ovl_cleanup_unlocked(ofs, old_upperdir, newdentry);
 
 	if (overwrite && d_inode(new)) {
 		if (new_is_dir)
@@ -1291,12 +1292,8 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir,
 	if (d_inode(new) && ovl_dentry_upper(new))
 		ovl_copyattr(d_inode(new));
 
-out_dput:
 	dput(newdentry);
-out_dput_old:
 	dput(olddentry);
-out_unlock:
-	unlock_rename(new_upperdir, old_upperdir);
 out_revert_creds:
 	ovl_revert_creds(old_cred);
 	if (update_nlink)
@@ -1307,6 +1304,14 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir,
 	dput(opaquedir);
 	ovl_cache_free(&list);
 	return err;
+
+out_dput:
+	dput(newdentry);
+out_dput_old:
+	dput(olddentry);
+out_unlock:
+	unlock_rename(new_upperdir, old_upperdir);
+	goto out_revert_creds;
 }
 
 static int ovl_create_tmpfile(struct file *file, struct dentry *dentry,
-- 
2.49.0