From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christian Brauner Subject: [PATCH 2/7] namespace: add kernel doc for mnt_clone_internal() Date: Wed, 14 Apr 2021 14:37:46 +0200 Message-ID: <20210414123750.2110159-3-brauner@kernel.org> References: <20210414123750.2110159-1-brauner@kernel.org> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: Received: from mail.kernel.org ([198.145.29.99]:33850 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232883AbhDNMjC (ORCPT ); Wed, 14 Apr 2021 08:39:02 -0400 In-Reply-To: <20210414123750.2110159-1-brauner@kernel.org> List-ID: Content-Type: text/plain; charset="us-ascii" To: linux-fsdevel@vger.kernel.org Cc: Amir Goldstein , Christoph Hellwig , Tyler Hicks , David Howells , Miklos Szeredi , Al Viro , ecryptfs@vger.kernel.org, linux-cachefs@redhat.com, Christian Brauner From: Christian Brauner Document mnt_clone_internal(). Cc: Amir Goldstein Cc: Christoph Hellwig Cc: Miklos Szeredi Cc: Al Viro Cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner --- fs/namespace.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/fs/namespace.c b/fs/namespace.c index 02f415061efe..7ffefa8b3980 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -1271,6 +1271,22 @@ bool path_is_mountpoint(const struct path *path) } EXPORT_SYMBOL(path_is_mountpoint); +/** + * mnt_clone_internal - create a private clone of a path + * @path: path from which the mnt to clone will be taken + * + * This creates a new vfsmount, which will be a clone of @path's vfsmount. + * + * In contrast to clone_private_mount() the new mount will be marked + * MNT_INTERNAL and will note have any mount namespace attached making it + * suitable for short-lived internal mounts since mntput()ing it will always + * hit the slowpath taking the mount lock. + * + * Since the mount is not reachable anwyhere mount properties and propagation + * properties remain stable, i.e. cannot change. + * + * Return: A clone of @path's vfsmount on success, an error pointer on failure. + */ struct vfsmount *mnt_clone_internal(const struct path *path) { struct mount *p; -- 2.27.0