From patchwork Tue Nov 23 01:29:35 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: NeilBrown X-Patchwork-Id: 12633327 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6792DC433F5 for ; Tue, 23 Nov 2021 01:32:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230040AbhKWBf1 (ORCPT ); Mon, 22 Nov 2021 20:35:27 -0500 Received: from smtp-out1.suse.de ([195.135.220.28]:57932 "EHLO smtp-out1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229874AbhKWBf1 (ORCPT ); Mon, 22 Nov 2021 20:35:27 -0500 Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id 857A4218B0; Tue, 23 Nov 2021 01:32:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1637631139; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=g/3zS1w9XPAB0sKrywf5beu0ueeIr7R6pDKbEKsXTPc=; b=beNwV92Z7vpxYnolbpkMahjFsLukUlosgj+lCH/qLdZvuFJaajGtGZPjjBXM7G88z62xb5 o7j/D1WvDlz7CZ8UBAmCLdPz41TURaQmATY6WoKsNfr/ePX+2F3SPmeT0WA1ONtuJqJbd2 yFleOze1ueCFp3ylrfikMbAS1BGv6sE= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1637631139; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=g/3zS1w9XPAB0sKrywf5beu0ueeIr7R6pDKbEKsXTPc=; b=KEOU1eO74MOkTelgioGA/zG1cfvgvc6blYXyOxdUw3JiGcGUYtvqYl0dRIhPHXEmnjDDI1 6AQqxTwCVgOPbQBw== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 7193E13BD4; Tue, 23 Nov 2021 01:32:18 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id Iuj3C6JEnGETdAAAMHmgww (envelope-from ); Tue, 23 Nov 2021 01:32:18 +0000 Subject: [PATCH 14/19] lockd: introduce lockd_put() From: NeilBrown To: "J. Bruce Fields" , Chuck Lever Cc: linux-nfs@vger.kernel.org Date: Tue, 23 Nov 2021 12:29:35 +1100 Message-ID: <163763097549.7284.13864576118395419236.stgit@noble.brown> In-Reply-To: <163763078330.7284.10141477742275086758.stgit@noble.brown> References: <163763078330.7284.10141477742275086758.stgit@noble.brown> User-Agent: StGit/0.23 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org There is some cleanup that is duplicated in lockd_down() and the failure path of lockd_up(). Factor these out into a new lockd_put() and call it from both places. lockd_put() does *not* take the mutex - that must be held by the caller. It decrements nlmsvc_users and if that reaches zero, it cleans up. Signed-off-by: NeilBrown --- fs/lockd/svc.c | 64 ++++++++++++++++++++++++-------------------------------- 1 file changed, 27 insertions(+), 37 deletions(-) diff --git a/fs/lockd/svc.c b/fs/lockd/svc.c index 9aa499a76159..7f12c280fd30 100644 --- a/fs/lockd/svc.c +++ b/fs/lockd/svc.c @@ -351,14 +351,6 @@ static struct notifier_block lockd_inet6addr_notifier = { }; #endif -static void lockd_unregister_notifiers(void) -{ - unregister_inetaddr_notifier(&lockd_inetaddr_notifier); -#if IS_ENABLED(CONFIG_IPV6) - unregister_inet6addr_notifier(&lockd_inet6addr_notifier); -#endif -} - static int lockd_start_svc(struct svc_serv *serv) { int error; @@ -450,6 +442,27 @@ static int lockd_create_svc(void) return 0; } +static void lockd_put(void) +{ + if (WARN(nlmsvc_users <= 0, "lockd_down: no users!\n")) + return; + if (--nlmsvc_users) + return; + + unregister_inetaddr_notifier(&lockd_inetaddr_notifier); +#if IS_ENABLED(CONFIG_IPV6) + unregister_inet6addr_notifier(&lockd_inet6addr_notifier); +#endif + + if (nlmsvc_task) { + kthread_stop(nlmsvc_task); + dprintk("lockd_down: service stopped\n"); + nlmsvc_task = NULL; + } + nlmsvc_serv = NULL; + dprintk("lockd_down: service destroyed\n"); +} + /* * Bring up the lockd process if it's not already up. */ @@ -461,21 +474,16 @@ int lockd_up(struct net *net, const struct cred *cred) error = lockd_create_svc(); if (error) - goto err_create; + goto err; + nlmsvc_users++; error = lockd_up_net(nlmsvc_serv, net, cred); if (error < 0) { - goto err_put; + lockd_put(); + goto err; } - nlmsvc_users++; -err_put: - if (nlmsvc_users == 0) { - lockd_unregister_notifiers(); - kthread_stop(nlmsvc_task); - nlmsvc_serv = NULL; - } -err_create: +err: mutex_unlock(&nlmsvc_mutex); return error; } @@ -489,25 +497,7 @@ lockd_down(struct net *net) { mutex_lock(&nlmsvc_mutex); lockd_down_net(nlmsvc_serv, net); - if (nlmsvc_users) { - if (--nlmsvc_users) - goto out; - } else { - printk(KERN_ERR "lockd_down: no users! task=%p\n", - nlmsvc_task); - BUG(); - } - - if (!nlmsvc_task) { - printk(KERN_ERR "lockd_down: no lockd running.\n"); - BUG(); - } - lockd_unregister_notifiers(); - kthread_stop(nlmsvc_task); - dprintk("lockd_down: service destroyed\n"); - nlmsvc_serv = NULL; - nlmsvc_task = NULL; -out: + lockd_put(); mutex_unlock(&nlmsvc_mutex); } EXPORT_SYMBOL_GPL(lockd_down);