From: tzsz <writing.segfaults@gmail.com>
To: linux-fsdevel@vger.kernel.org
Subject: Swapping fs root inode without unmounting
Date: Fri, 7 Mar 2025 16:39:21 +0100 [thread overview]
Message-ID: <51d24177-482e-4355-8e14-689752dfa36e@gmail.com> (raw)
Hello!
We are currently developing a snapshot feature for a small university
project. And for this reason we are looking for a way to swap out the
root inode of our (mounted) fs.
Internally we have a set of root inodes and we'd like to swap them out
at will without unmounting the entire filesystem.
Is there any function/way how to do this properly?
So far we tried the following:
-> swapping dentry: setting sb->s_root
-> causes a lot of problems regarding inode ref counting (I_CLEAR flag)
-> looking into fs_context (doesnt seem like this is appropriate here)
-> we did not find anything related within the vfs.rst docs
Furthermore, we cannot mount those other root inodes at different
mountpoints. All changes have to be live and in-place.
Kind regards
next reply other threads:[~2025-03-07 15:39 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-03-07 15:39 tzsz [this message]
2025-03-10 8:04 ` Swapping fs root inode without unmounting Christian Brauner
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