linux-ext4 - Re: [PATCH v2 1/5] fscrypt: clean up and improve dentry revalidation

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Message-ID: <20190416230840.GB14623@mit.edu>
Date:   Tue, 16 Apr 2019 19:08:40 -0400
From:   "Theodore Ts'o" <tytso@....edu>
To:     Eric Biggers <ebiggers@...nel.org>
Cc:     linux-fscrypt@...r.kernel.org, linux-fsdevel@...r.kernel.org,
        linux-ext4@...r.kernel.org, linux-f2fs-devel@...ts.sourceforge.net,
        linux-mtd@...ts.infradead.org, linux-unionfs@...r.kernel.org,
        Sarthak Kukreti <sarthakkukreti@...omium.org>,
        Gao Xiang <gaoxiang25@...wei.com>
Subject: Re: [PATCH v2 1/5] fscrypt: clean up and improve dentry revalidation

On Wed, Mar 20, 2019 at 11:39:09AM -0700, Eric Biggers wrote:
> From: Eric Biggers <ebiggers@...gle.com>
> 
> Make various improvements to fscrypt dentry revalidation:
> 
> - Don't try to handle the case where the per-directory key is removed,
>   as this can't happen without the inode (and dentries) being evicted.
> 
> - Flag ciphertext dentries rather than plaintext dentries, since it's
>   ciphertext dentries that need the special handling.
> 
> - Avoid doing unnecessary work for non-ciphertext dentries.
> 
> - When revalidating ciphertext dentries, try to set up the directory's
>   i_crypt_info to make sure the key is really still absent, rather than
>   invalidating all negative dentries as the previous code did.  An old
>   comment suggested we can't do this for locking reasons, but AFAICT
>   this comment was outdated and it actually works fine.
> 
> Signed-off-by: Eric Biggers <ebiggers@...gle.com>

Looks good, applied.

					- Ted