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Date:   Thu, 11 May 2023 07:19:36 -0700
From:   Seth Forshee <sforshee@kernel.org>
To:     Christian Brauner <brauner@kernel.org>
Cc:     Al Viro <viro@zeniv.linux.org.uk>, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH v4 4/4] fs: allow to mount beneath top mount
Message-ID: <ZFz5eI9WoWzMvXS3@do-x1extreme>
References: <20230202-fs-move-mount-replace-v4-0-98f3d80d7eaa@kernel.org>
 <20230202-fs-move-mount-replace-v4-4-98f3d80d7eaa@kernel.org>
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On Wed, May 03, 2023 at 01:18:42PM +0200, Christian Brauner wrote:
> +/**
> + * do_lock_mount - lock mount and mountpoint
> + * @path:    target path
> + * @beneath: whether the intention is to mount beneath @path
> + *
> + * Follow the mount stack on @path until the top mount @mnt is found. If
> + * the initial @path->{mnt,dentry} is a mountpoint lookup the first
> + * mount stacked on top of it. Then simply follow @{mnt,mnt->mnt_root}
> + * until nothing is stacked on top of it anymore.
> + *
> + * Acquire the inode_lock() on the top mount's ->mnt_root to protect
> + * against concurrent removal of the new mountpoint from another mount
> + * namespace.
> + *
> + * If @beneath is requested, acquire inode_lock() on @mnt's mountpoint
> + * @mp on @mnt->mnt_parent must be acquired. This protects against a

Redundant use of "acquire" here.