From: "J. Bruce Fields" Subject: [PATCH 1/7] nfsd4: fix v4 state shutdown error paths Date: Wed, 21 Jul 2010 19:26:45 -0400 Message-ID: <1279754811-8328-1-git-send-email-bfields@redhat.com> References: <20100721232432.GA6689@fieldses.org> Cc: linux-nfs@vger.kernel.org, Jeff Layton , "J. Bruce Fields" To: Jeff Layton Return-path: Received: from fieldses.org ([174.143.236.118]:46642 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755340Ab0GUX1n (ORCPT ); Wed, 21 Jul 2010 19:27:43 -0400 In-Reply-To: <20100721232432.GA6689@fieldses.org> Sender: linux-nfs-owner@vger.kernel.org List-ID: From: Jeff Layton If someone tries to shut down the laundry_wq while it isn't up it'll cause an oops. This can happen because write_ports can create a nfsd_svc before we really start the nfs server, and we may fail before the server is ever started. Also make sure state is shutdown on error paths in nfsd_svc(). Use a common global nfsd_up flag instead of nfs4_init, and create common helper functions for nfsd start/shutdown, as there will be other work that we want done only when we the number of nfsd threads transitions between zero and nonzero. Signed-off-by: J. Bruce Fields --- fs/nfsd/nfs4state.c | 12 +----------- fs/nfsd/nfssvc.c | 51 ++++++++++++++++++++++++++++++++++++++++++--------- 2 files changed, 43 insertions(+), 20 deletions(-) diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 182448f..9cc3b78 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -51,7 +51,6 @@ static time_t boot_time; static u32 current_ownerid = 1; static u32 current_fileid = 1; static u32 current_delegid = 1; -static u32 nfs4_init; static stateid_t zerostateid; /* bits all 0 */ static stateid_t onestateid; /* bits all 1 */ static u64 current_sessionid = 1; @@ -4071,16 +4070,8 @@ out_free_laundry: int nfs4_state_start(void) { - int ret; - - if (nfs4_init) - return 0; nfsd4_load_reboot_recovery_data(); - ret = __nfs4_state_start(); - if (ret) - return ret; - nfs4_init = 1; - return 0; + return __nfs4_state_start(); } static void @@ -4115,7 +4106,6 @@ __nfs4_state_shutdown(void) } nfsd4_shutdown_recdir(); - nfs4_init = 0; } void diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c index 06b2a26..d7a4d7b 100644 --- a/fs/nfsd/nfssvc.c +++ b/fs/nfsd/nfssvc.c @@ -180,6 +180,31 @@ int nfsd_nrthreads(void) return rv; } +static bool nfsd_up = false; + +static int nfsd_startup(unsigned short port, int nrservs) +{ + int ret; + + ret = nfs4_state_start(); + nfsd_up = true; + return ret; +} + +static void nfsd_shutdown(void) +{ + /* + * write_ports can create the server without actually starting + * any threads--if we get shut down before any threads are + * started, then nfsd_last_thread will be run before any of this + * other initialization has been done. + */ + if (!nfsd_up) + return; + nfs4_state_shutdown(); + nfsd_up = false; +} + static void nfsd_last_thread(struct svc_serv *serv) { /* When last nfsd thread exits we need to do some clean-up */ @@ -188,7 +213,7 @@ static void nfsd_last_thread(struct svc_serv *serv) lockd_down(); nfsd_serv = NULL; nfsd_racache_shutdown(); - nfs4_state_shutdown(); + nfsd_shutdown(); printk(KERN_WARNING "nfsd: last server has exited, flushing export " "cache\n"); @@ -380,6 +405,7 @@ int nfsd_svc(unsigned short port, int nrservs) { int error; + bool first_thread; mutex_lock(&nfsd_mutex); dprintk("nfsd: creating service\n"); @@ -395,19 +421,23 @@ nfsd_svc(unsigned short port, int nrservs) error = nfsd_racache_init(2*nrservs); if (error<0) goto out; - error = nfs4_state_start(); - if (error) - goto out; + + first_thread = (nfsd_serv->sv_nrthreads == 0) && (nrservs != 0); + + if (first_thread) { + error = nfsd_startup(port, nrservs); + if (error) + goto out; + } nfsd_reset_versions(); error = nfsd_create_serv(); - if (error) - goto out; + goto out_shutdown; error = nfsd_init_socks(port); if (error) - goto failure; + goto out_destroy; error = svc_set_num_threads(nfsd_serv, NULL, nrservs); if (error == 0) @@ -416,9 +446,12 @@ nfsd_svc(unsigned short port, int nrservs) * so subtract 1 */ error = nfsd_serv->sv_nrthreads - 1; - failure: +out_destroy: svc_destroy(nfsd_serv); /* Release server */ - out: +out_shutdown: + if (error < 0 && first_thread) + nfsd_shutdown(); +out: mutex_unlock(&nfsd_mutex); return error; } -- 1.7.0.4