From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A96E0C2D0E2 for ; Wed, 23 Sep 2020 20:44:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5842620C09 for ; Wed, 23 Sep 2020 20:44:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726518AbgIWUof (ORCPT ); Wed, 23 Sep 2020 16:44:35 -0400 Received: from bhuna.collabora.co.uk ([46.235.227.227]:47686 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726199AbgIWUof (ORCPT ); Wed, 23 Sep 2020 16:44:35 -0400 X-Greylist: delayed 1561 seconds by postgrey-1.27 at vger.kernel.org; Wed, 23 Sep 2020 16:44:34 EDT Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: krisman) with ESMTPSA id 0338129C28A From: Gabriel Krisman Bertazi To: Daniel Rosenberg Cc: "Theodore Y . Ts'o" , Jaegeuk Kim , Eric Biggers , Andreas Dilger , Chao Yu , Alexander Viro , Richard Weinberger , linux-fscrypt@vger.kernel.org, linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mtd@lists.infradead.org, kernel-team@android.com Subject: Re: [PATCH 3/5] libfs: Add generic function for setting dentry_ops Organization: Collabora References: <20200923010151.69506-1-drosen@google.com> <20200923010151.69506-4-drosen@google.com> Date: Wed, 23 Sep 2020 16:44:28 -0400 In-Reply-To: <20200923010151.69506-4-drosen@google.com> (Daniel Rosenberg's message of "Wed, 23 Sep 2020 01:01:49 +0000") Message-ID: <87ft785ikz.fsf@collabora.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Daniel Rosenberg writes: > This adds a function to set dentry operations at lookup time that will > work for both encrypted files and casefolded filenames. > > A filesystem that supports both features simultaneously can use this > function during lookup preperations to set up its dentry operations once > fscrypt no longer does that itself. > > Currently the casefolding dentry operation are always set because the > feature is toggleable on empty directories. Since we don't know what > set of functions we'll eventually need, and cannot change them later, > we add just add them. > > Signed-off-by: Daniel Rosenberg > --- > fs/libfs.c | 49 ++++++++++++++++++++++++++++++++++++++++++++++ > include/linux/fs.h | 1 + > 2 files changed, 50 insertions(+) > > diff --git a/fs/libfs.c b/fs/libfs.c > index fc34361c1489..83303858f1fe 100644 > --- a/fs/libfs.c > +++ b/fs/libfs.c > @@ -1449,4 +1449,53 @@ int generic_ci_d_hash(const struct dentry *dentry, struct qstr *str) > return 0; > } > EXPORT_SYMBOL(generic_ci_d_hash); > + > +static const struct dentry_operations generic_ci_dentry_ops = { > + .d_hash = generic_ci_d_hash, > + .d_compare = generic_ci_d_compare, > +}; > +#endif > + > +#ifdef CONFIG_FS_ENCRYPTION > +static const struct dentry_operations generic_encrypted_dentry_ops = { > + .d_revalidate = fscrypt_d_revalidate, > +}; > +#endif > + > +#if IS_ENABLED(CONFIG_UNICODE) && IS_ENABLED(CONFIG_FS_ENCRYPTION) > +static const struct dentry_operations generic_encrypted_ci_dentry_ops = { > + .d_hash = generic_ci_d_hash, > + .d_compare = generic_ci_d_compare, > + .d_revalidate = fscrypt_d_revalidate, > +}; > +#endif > + > +/** > + * generic_set_encrypted_ci_d_ops - helper for setting d_ops for given dentry > + * @dentry: dentry to set ops on > + * > + * This function sets the dentry ops for the given dentry to handle both > + * casefolding and encryption of the dentry name. > + */ > +void generic_set_encrypted_ci_d_ops(struct dentry *dentry) > +{ > +#ifdef CONFIG_FS_ENCRYPTION > + if (dentry->d_flags & DCACHE_ENCRYPTED_NAME) { > +#ifdef CONFIG_UNICODE > + if (dentry->d_sb->s_encoding) { > + d_set_d_op(dentry, &generic_encrypted_ci_dentry_ops); > + return; > + } > #endif > + d_set_d_op(dentry, &generic_encrypted_dentry_ops); > + return; > + } > +#endif > +#ifdef CONFIG_UNICODE > + if (dentry->d_sb->s_encoding) { > + d_set_d_op(dentry, &generic_ci_dentry_ops); > + return; > + } > +#endif > +} I think this is harder to read than necessary. What do you think about just splitting the three cases like the following: void generic_set_encrypted_ci_d_ops(struct dentry *dentry) { #if defined(CONFIG_FS_ENCRYPTION) && defined(CONFIG_UNICODE) if (encoding && encryption) { d_set_d_op(dentry, &generic_encrypted_ci_dentry_ops); return; } #endif #if defined (CONFIG_FS_ENCRYPTION) if (encryption) { d_set_d_op(dentry, &generic_encrypted_dentry_ops); return; } #endif #if defined (CONFIG_UNICODE) if (encoding) { d_set_d_op(dentry, &generic_ci_dentry_ops); return; } #endif } > +EXPORT_SYMBOL(generic_set_encrypted_ci_d_ops); > diff --git a/include/linux/fs.h b/include/linux/fs.h > index bc5417c61e12..6627896db835 100644 > --- a/include/linux/fs.h > +++ b/include/linux/fs.h > @@ -3277,6 +3277,7 @@ extern int generic_ci_d_hash(const struct dentry *dentry, struct qstr *str); > extern int generic_ci_d_compare(const struct dentry *dentry, unsigned int len, > const char *str, const struct qstr *name); > #endif > +extern void generic_set_encrypted_ci_d_ops(struct dentry *dentry); > > #ifdef CONFIG_MIGRATION > extern int buffer_migrate_page(struct address_space *, -- Gabriel Krisman Bertazi