2020-11-22 04:56:57

by Gabriel Krisman Bertazi

[permalink] [raw]
Subject: Re: [PATCH v4 1/3] libfs: Add generic function for setting dentry_ops

Daniel Rosenberg <[email protected]> writes:

> This adds a function to set dentry operations at lookup time that will
> work for both encrypted filenames and casefolded filenames.
>
> A filesystem that supports both features simultaneously can use this
> function during lookup preparations to set up its dentry operations once
> fscrypt no longer does that itself.
>
> Currently the casefolding dentry operation are always set if the
> filesystem defines an encoding because the features is toggleable on
> empty directories. Unlike in the encryption case, the dentry operations
> used come from the parent. Since we don't know what set of functions
> we'll eventually need, and cannot change them later, we enable the
> casefolding operations if the filesystem supports them at all.
>
> By splitting out the various cases, we support as few dentry operations
> as we can get away with, maximizing compatibility with overlayfs, which
> will not function if a filesystem supports certain dentry_operations.
>
> Signed-off-by: Daniel Rosenberg <[email protected]>
> Reviewed-by: Eric Biggers <[email protected]>

Reviewed-by: Gabriel Krisman Bertazi <[email protected]>

--
Gabriel Krisman Bertazi