From patchwork Tue Jul 3 12:46:41 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stanislav Kinsbursky X-Patchwork-Id: 1150851 Return-Path: X-Original-To: patchwork-linux-nfs@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork1.kernel.org (Postfix) with ESMTP id 3E54E3FE4F for ; Tue, 3 Jul 2012 12:49:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753277Ab2GCMt4 (ORCPT ); Tue, 3 Jul 2012 08:49:56 -0400 Received: from mailhub.sw.ru ([195.214.232.25]:18579 "EHLO relay.sw.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751998Ab2GCMt4 (ORCPT ); Tue, 3 Jul 2012 08:49:56 -0400 Received: from localhost.localdomain ([10.30.21.131]) by relay.sw.ru (8.13.4/8.13.4) with ESMTP id q63CnitI005739; Tue, 3 Jul 2012 16:49:45 +0400 (MSK) Subject: [PATCH v3] NFSd: set nfsd_serv to NULL after service destruction To: bfields@fieldses.org From: Stanislav Kinsbursky Cc: linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org, devel@openvz.org Date: Tue, 03 Jul 2012 16:46:41 +0400 Message-ID: <20120703124603.3766.26607.stgit@localhost.localdomain> User-Agent: StGit/0.16 MIME-Version: 1.0 Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org v3: 1) Rebased for 3.6 kernel. v2: 1) Set global nfsd_serv pointer to NULL only if no running threads left. Otherwise we will get NULL pointer dereference on last thread exit in nfsd_last_thread(). This patch also introduces nfsd_destroy() helper for per-net NFSd shutdown. Signed-off-by: Stanislav Kinsbursky --- fs/nfsd/nfsctl.c | 8 ++------ fs/nfsd/nfsd.h | 11 +++++++++++ fs/nfsd/nfssvc.c | 24 ++++++++---------------- 3 files changed, 21 insertions(+), 22 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c index c55298e..fa49cff 100644 --- a/fs/nfsd/nfsctl.c +++ b/fs/nfsd/nfsctl.c @@ -673,9 +673,7 @@ static ssize_t __write_ports_addfd(char *buf) err = svc_addsock(nfsd_serv, fd, buf, SIMPLE_TRANSACTION_LIMIT); if (err < 0) { - if (nfsd_serv->sv_nrthreads == 1) - svc_shutdown_net(nfsd_serv, net); - svc_destroy(nfsd_serv); + nfsd_destroy(net); return err; } @@ -744,9 +742,7 @@ out_close: svc_xprt_put(xprt); } out_err: - if (nfsd_serv->sv_nrthreads == 1) - svc_shutdown_net(nfsd_serv, net); - svc_destroy(nfsd_serv); + nfsd_destroy(net); return err; } diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h index 1671429..1336a65 100644 --- a/fs/nfsd/nfsd.h +++ b/fs/nfsd/nfsd.h @@ -73,6 +73,17 @@ int nfsd_nrpools(void); int nfsd_get_nrthreads(int n, int *); int nfsd_set_nrthreads(int n, int *); +static inline void nfsd_destroy(struct net *net) +{ + int destroy = (nfsd_serv->sv_nrthreads == 1); + + if (destroy) + svc_shutdown_net(nfsd_serv, net); + svc_destroy(nfsd_serv); + if (destroy) + nfsd_serv = NULL; +} + #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) #ifdef CONFIG_NFSD_V2_ACL extern struct svc_version nfsd_acl_version2; diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c index ee709fc..240473c 100644 --- a/fs/nfsd/nfssvc.c +++ b/fs/nfsd/nfssvc.c @@ -254,8 +254,6 @@ static void nfsd_shutdown(void) static void nfsd_last_thread(struct svc_serv *serv, struct net *net) { - /* When last nfsd thread exits we need to do some clean-up */ - nfsd_serv = NULL; nfsd_shutdown(); svc_rpcb_cleanup(serv, net); @@ -332,6 +330,7 @@ static int nfsd_get_default_max_blksize(void) int nfsd_create_serv(void) { int error; + struct net *net = current->nsproxy->net_ns; WARN_ON(!mutex_is_locked(&nfsd_mutex)); if (nfsd_serv) { @@ -346,7 +345,7 @@ int nfsd_create_serv(void) if (nfsd_serv == NULL) return -ENOMEM; - error = svc_bind(nfsd_serv, current->nsproxy->net_ns); + error = svc_bind(nfsd_serv, net); if (error < 0) { svc_destroy(nfsd_serv); return error; @@ -427,11 +426,7 @@ int nfsd_set_nrthreads(int n, int *nthreads) if (err) break; } - - if (nfsd_serv->sv_nrthreads == 1) - svc_shutdown_net(nfsd_serv, net); - svc_destroy(nfsd_serv); - + nfsd_destroy(net); return err; } @@ -478,9 +473,7 @@ out_shutdown: if (error < 0 && !nfsd_up_before) nfsd_shutdown(); out_destroy: - if (nfsd_serv->sv_nrthreads == 1) - svc_shutdown_net(nfsd_serv, net); - svc_destroy(nfsd_serv); /* Release server */ + nfsd_destroy(net); /* Release server */ out: mutex_unlock(&nfsd_mutex); return error; @@ -563,12 +556,13 @@ nfsd(void *vrqstp) nfsdstats.th_cnt --; out: - if (rqstp->rq_server->sv_nrthreads == 1) - svc_shutdown_net(rqstp->rq_server, &init_net); + rqstp->rq_server = NULL; /* Release the thread */ svc_exit_thread(rqstp); + nfsd_destroy(&init_net); + /* Release module */ mutex_unlock(&nfsd_mutex); module_put_and_exit(0); @@ -682,9 +676,7 @@ int nfsd_pool_stats_release(struct inode *inode, struct file *file) mutex_lock(&nfsd_mutex); /* this function really, really should have been called svc_put() */ - if (nfsd_serv->sv_nrthreads == 1) - svc_shutdown_net(nfsd_serv, net); - svc_destroy(nfsd_serv); + nfsd_destroy(net); mutex_unlock(&nfsd_mutex); return ret; }