Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail-qg0-f41.google.com ([209.85.192.41]:59405 "EHLO mail-qg0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755249AbaGUPDM (ORCPT ); Mon, 21 Jul 2014 11:03:12 -0400 Received: by mail-qg0-f41.google.com with SMTP id q107so5472231qgd.14 for ; Mon, 21 Jul 2014 08:03:10 -0700 (PDT) From: Jeff Layton To: bfields@fieldses.org Cc: linux-nfs@vger.kernel.org, hch@infradead.org Subject: [PATCH 08/40] nfsd: Add locking to protect the state owner lists Date: Mon, 21 Jul 2014 11:02:20 -0400 Message-Id: <1405954972-28904-9-git-send-email-jlayton@primarydata.com> In-Reply-To: <1405954972-28904-1-git-send-email-jlayton@primarydata.com> References: <1405954972-28904-1-git-send-email-jlayton@primarydata.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: Change to using the clp->cl_lock for this. For now, there's a lot of cl_lock thrashing, but in later patches we'll eliminate that and close the potential races that can occur when releasing the cl_lock while walking the lists. For now, the client_mutex prevents those races. Signed-off-by: Trond Myklebust Signed-off-by: Jeff Layton --- fs/nfsd/nfs4state.c | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-) diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index cedf86a3b9b7..c61f9475f1c6 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -897,6 +897,8 @@ static void unhash_generic_stateid(struct nfs4_ol_stateid *stp) { struct nfs4_file *fp = stp->st_stid.sc_file; + lockdep_assert_held(&stp->st_stateowner->so_client->cl_lock); + spin_lock(&fp->fi_lock); list_del(&stp->st_perfile); spin_unlock(&fp->fi_lock); @@ -930,9 +932,13 @@ static void put_generic_stateid(struct nfs4_ol_stateid *stp) static void __release_lock_stateid(struct nfs4_ol_stateid *stp) { + struct nfs4_openowner *oo = openowner(stp->st_openstp->st_stateowner); + + spin_lock(&oo->oo_owner.so_client->cl_lock); list_del(&stp->st_locks); unhash_generic_stateid(stp); unhash_stid(&stp->st_stid); + spin_unlock(&oo->oo_owner.so_client->cl_lock); put_generic_stateid(stp); } @@ -976,20 +982,26 @@ static void release_lock_stateid(struct nfs4_ol_stateid *stp) } static void release_open_stateid_locks(struct nfs4_ol_stateid *open_stp) + __releases(&open_stp->st_stateowner->so_client->cl_lock) + __acquires(&open_stp->st_stateowner->so_client->cl_lock) { struct nfs4_ol_stateid *stp; while (!list_empty(&open_stp->st_locks)) { stp = list_entry(open_stp->st_locks.next, struct nfs4_ol_stateid, st_locks); + spin_unlock(&open_stp->st_stateowner->so_client->cl_lock); release_lock_stateid(stp); + spin_lock(&open_stp->st_stateowner->so_client->cl_lock); } } static void unhash_open_stateid(struct nfs4_ol_stateid *stp) { + spin_lock(&stp->st_stateowner->so_client->cl_lock); unhash_generic_stateid(stp); release_open_stateid_locks(stp); + spin_unlock(&stp->st_stateowner->so_client->cl_lock); } static void release_open_stateid(struct nfs4_ol_stateid *stp) @@ -3001,7 +3013,6 @@ static void init_open_stateid(struct nfs4_ol_stateid *stp, struct nfs4_file *fp, stp->st_stid.sc_type = NFS4_OPEN_STID; INIT_LIST_HEAD(&stp->st_locks); - list_add(&stp->st_perstateowner, &oo->oo_owner.so_stateids); stp->st_stateowner = &oo->oo_owner; get_nfs4_file(fp); stp->st_stid.sc_file = fp; @@ -3010,9 +3021,12 @@ static void init_open_stateid(struct nfs4_ol_stateid *stp, struct nfs4_file *fp, set_access(open->op_share_access, stp); set_deny(open->op_share_deny, stp); stp->st_openstp = NULL; + spin_lock(&oo->oo_owner.so_client->cl_lock); + list_add(&stp->st_perstateowner, &oo->oo_owner.so_stateids); spin_lock(&fp->fi_lock); list_add(&stp->st_perfile, &fp->fi_stateids); spin_unlock(&fp->fi_lock); + spin_unlock(&oo->oo_owner.so_client->cl_lock); } static void @@ -4716,6 +4730,7 @@ alloc_init_lock_stateowner(unsigned int strhashval, struct nfs4_client *clp, str static struct nfs4_ol_stateid * alloc_init_lock_stateid(struct nfs4_lockowner *lo, struct nfs4_file *fp, struct nfs4_ol_stateid *open_stp) { + struct nfs4_openowner *oo = openowner(open_stp->st_stateowner); struct nfs4_ol_stateid *stp; struct nfs4_client *clp = lo->lo_owner.so_client; @@ -4723,7 +4738,6 @@ alloc_init_lock_stateid(struct nfs4_lockowner *lo, struct nfs4_file *fp, struct if (stp == NULL) return NULL; stp->st_stid.sc_type = NFS4_LOCK_STID; - list_add(&stp->st_perstateowner, &lo->lo_owner.so_stateids); stp->st_stateowner = &lo->lo_owner; get_nfs4_file(fp); stp->st_stid.sc_file = fp; @@ -4731,10 +4745,13 @@ alloc_init_lock_stateid(struct nfs4_lockowner *lo, struct nfs4_file *fp, struct stp->st_access_bmap = 0; stp->st_deny_bmap = open_stp->st_deny_bmap; stp->st_openstp = open_stp; + spin_lock(&oo->oo_owner.so_client->cl_lock); list_add(&stp->st_locks, &open_stp->st_locks); + list_add(&stp->st_perstateowner, &lo->lo_owner.so_stateids); spin_lock(&fp->fi_lock); list_add(&stp->st_perfile, &fp->fi_stateids); spin_unlock(&fp->fi_lock); + spin_unlock(&oo->oo_owner.so_client->cl_lock); return stp; } -- 1.9.3