From patchwork Wed May 12 00:38:46 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ian Kent X-Patchwork-Id: 12252441 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=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 11E1FC433B4 for ; Wed, 12 May 2021 00:38:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DFD8561628 for ; Wed, 12 May 2021 00:38:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229994AbhELAkE convert rfc822-to-8bit (ORCPT ); Tue, 11 May 2021 20:40:04 -0400 Received: from us-smtp-delivery-44.mimecast.com ([205.139.111.44]:26130 "EHLO us-smtp-delivery-44.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229932AbhELAkD (ORCPT ); Tue, 11 May 2021 20:40:03 -0400 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-46-uks3IF0YPbGm-xEnmo-Z6w-1; Tue, 11 May 2021 20:38:52 -0400 X-MC-Unique: uks3IF0YPbGm-xEnmo-Z6w-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 33488FC8D; Wed, 12 May 2021 00:38:51 +0000 (UTC) Received: from web.messagingengine.com (ovpn-116-20.sin2.redhat.com [10.67.116.20]) by smtp.corp.redhat.com (Postfix) with ESMTP id E8ECE6E519; Wed, 12 May 2021 00:38:47 +0000 (UTC) Subject: [PATCH v4 1/5] kernfs: move revalidate to be near lookup From: Ian Kent To: Greg Kroah-Hartman , Tejun Heo Cc: Al Viro , Eric Sandeen , Fox Chen , Brice Goglin , Rick Lindsley , David Howells , Miklos Szeredi , Marcelo Tosatti , linux-fsdevel , Kernel Mailing List Date: Wed, 12 May 2021 08:38:46 +0800 Message-ID: <162077992651.14498.9682663898041297408.stgit@web.messagingengine.com> In-Reply-To: <162077975380.14498.11347675368470436331.stgit@web.messagingengine.com> References: <162077975380.14498.11347675368470436331.stgit@web.messagingengine.com> User-Agent: StGit/0.23 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=raven@themaw.net X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: themaw.net Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org While the dentry operation kernfs_dop_revalidate() is grouped with dentry type functions it also has a strong affinity to the inode operation ->lookup(). In order to take advantage of the VFS negative dentry caching that can be used to reduce path lookup overhead on non-existent paths it will need to call kernfs_find_ns(). So, to avoid a forward declaration, move it to be near kernfs_iop_lookup(). There's no functional change from this patch. Signed-off-by: Ian Kent --- fs/kernfs/dir.c | 86 ++++++++++++++++++++++++++++--------------------------- 1 file changed, 43 insertions(+), 43 deletions(-) diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c index 7e0e62deab53c..4c69e2af82dac 100644 --- a/fs/kernfs/dir.c +++ b/fs/kernfs/dir.c @@ -548,49 +548,6 @@ void kernfs_put(struct kernfs_node *kn) } EXPORT_SYMBOL_GPL(kernfs_put); -static int kernfs_dop_revalidate(struct dentry *dentry, unsigned int flags) -{ - struct kernfs_node *kn; - - if (flags & LOOKUP_RCU) - return -ECHILD; - - /* Always perform fresh lookup for negatives */ - if (d_really_is_negative(dentry)) - goto out_bad_unlocked; - - kn = kernfs_dentry_node(dentry); - mutex_lock(&kernfs_mutex); - - /* The kernfs node has been deactivated */ - if (!kernfs_active(kn)) - goto out_bad; - - /* The kernfs node has been moved? */ - if (kernfs_dentry_node(dentry->d_parent) != kn->parent) - goto out_bad; - - /* The kernfs node has been renamed */ - if (strcmp(dentry->d_name.name, kn->name) != 0) - goto out_bad; - - /* The kernfs node has been moved to a different namespace */ - if (kn->parent && kernfs_ns_enabled(kn->parent) && - kernfs_info(dentry->d_sb)->ns != kn->ns) - goto out_bad; - - mutex_unlock(&kernfs_mutex); - return 1; -out_bad: - mutex_unlock(&kernfs_mutex); -out_bad_unlocked: - return 0; -} - -const struct dentry_operations kernfs_dops = { - .d_revalidate = kernfs_dop_revalidate, -}; - /** * kernfs_node_from_dentry - determine kernfs_node associated with a dentry * @dentry: the dentry in question @@ -1073,6 +1030,49 @@ struct kernfs_node *kernfs_create_empty_dir(struct kernfs_node *parent, return ERR_PTR(rc); } +static int kernfs_dop_revalidate(struct dentry *dentry, unsigned int flags) +{ + struct kernfs_node *kn; + + if (flags & LOOKUP_RCU) + return -ECHILD; + + /* Always perform fresh lookup for negatives */ + if (d_really_is_negative(dentry)) + goto out_bad_unlocked; + + kn = kernfs_dentry_node(dentry); + mutex_lock(&kernfs_mutex); + + /* The kernfs node has been deactivated */ + if (!kernfs_active_read(kn)) + goto out_bad; + + /* The kernfs node has been moved? */ + if (kernfs_dentry_node(dentry->d_parent) != kn->parent) + goto out_bad; + + /* The kernfs node has been renamed */ + if (strcmp(dentry->d_name.name, kn->name) != 0) + goto out_bad; + + /* The kernfs node has been moved to a different namespace */ + if (kn->parent && kernfs_ns_enabled(kn->parent) && + kernfs_info(dentry->d_sb)->ns != kn->ns) + goto out_bad; + + mutex_unlock(&kernfs_mutex); + return 1; +out_bad: + mutex_unlock(&kernfs_mutex); +out_bad_unlocked: + return 0; +} + +const struct dentry_operations kernfs_dops = { + .d_revalidate = kernfs_dop_revalidate, +}; + static struct dentry *kernfs_iop_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)