From patchwork Tue Dec 12 22:57:09 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: NeilBrown X-Patchwork-Id: 10108419 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id A2D776032B for ; Tue, 12 Dec 2017 22:57:20 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8D1341FF41 for ; Tue, 12 Dec 2017 22:57:20 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 80BEE28526; Tue, 12 Dec 2017 22:57:20 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_TVD_MIME_EPI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DBDF31FF41 for ; Tue, 12 Dec 2017 22:57:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752680AbdLLW5T (ORCPT ); Tue, 12 Dec 2017 17:57:19 -0500 Received: from mx2.suse.de ([195.135.220.15]:42620 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752679AbdLLW5S (ORCPT ); Tue, 12 Dec 2017 17:57:18 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 046DDAEAB; Tue, 12 Dec 2017 22:57:16 +0000 (UTC) From: NeilBrown To: Trond Myklebust , Anna Schumaker Date: Wed, 13 Dec 2017 09:57:09 +1100 Cc: linux-nfs@vger.kernel.org Subject: [PATCH] NFSv4: always set NFS_LOCK_LOST when a lock is lost. Message-ID: <87r2rzo8qi.fsf@notabene.neil.brown.name> MIME-Version: 1.0 Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP There are 2 comments in the NFSv4 code which suggest that SIGLOST should possibly be sent to a process. In these cases a lock has been lost. The current practice is to set NFS_LOCK_LOST so that read/write returns EIO when a lock is lost. So change these comments to code when sets NFS_LOCK_LOST. One case is when lock recovery after apparent server restart fails with NFS4ERR_DENIED, NFS4ERR_RECLAIM_BAD, or NFS4ERRO_RECLAIM_CONFLICT. The other case is when a lock attempt as part of lease recovery fails with NFS4ERR_DENIED. In an ideal world, these should not happen. However I have a packet trace showing an NFSv4.1 session getting NFS4ERR_BADSESSION after an extended network parition. The NFSv4.1 client treats this like server reboot until/unless it get NFS4ERR_NO_GRACE, in which case it switches over to "nograce" recovery mode. In this network trace, the client attempts to recover a lock and the server (incorrectly) reports NFS4ERR_DENIED rather than NFS4ERR_NO_GRACE. This leads to the ineffective comment and the client then continues to write using the OPEN stateid. Signed-off-by: NeilBrown --- Note that I have not tested this as I do not have direct access to a faulty NFS server. Once I get confirmation I will provide an update. NeilBrown fs/nfs/nfs4proc.c | 12 ++++++++---- fs/nfs/nfs4state.c | 5 ++++- 2 files changed, 12 insertions(+), 5 deletions(-) diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 56fa5a16e097..083802f7a1e9 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -2019,7 +2019,7 @@ static int nfs4_open_reclaim(struct nfs4_state_owner *sp, struct nfs4_state *sta return ret; } -static int nfs4_handle_delegation_recall_error(struct nfs_server *server, struct nfs4_state *state, const nfs4_stateid *stateid, int err) +static int nfs4_handle_delegation_recall_error(struct nfs_server *server, struct nfs4_state *state, const nfs4_stateid *stateid, struct file_lock *fl, int err) { switch (err) { default: @@ -2066,7 +2066,11 @@ static int nfs4_handle_delegation_recall_error(struct nfs_server *server, struct return -EAGAIN; case -ENOMEM: case -NFS4ERR_DENIED: - /* kill_proc(fl->fl_pid, SIGLOST, 1); */ + if (fl) { + struct nfs4_lock_state *lsp = fl->fl_u.nfs4_fl.owner; + if (lsp) + set_bit(NFS_LOCK_LOST, &lsp->ls_flags); + } return 0; } return err; @@ -2102,7 +2106,7 @@ int nfs4_open_delegation_recall(struct nfs_open_context *ctx, err = nfs4_open_recover_helper(opendata, FMODE_READ); } nfs4_opendata_put(opendata); - return nfs4_handle_delegation_recall_error(server, state, stateid, err); + return nfs4_handle_delegation_recall_error(server, state, stateid, NULL, err); } static void nfs4_open_confirm_prepare(struct rpc_task *task, void *calldata) @@ -6739,7 +6743,7 @@ int nfs4_lock_delegation_recall(struct file_lock *fl, struct nfs4_state *state, if (err != 0) return err; err = _nfs4_do_setlk(state, F_SETLK, fl, NFS_LOCK_NEW); - return nfs4_handle_delegation_recall_error(server, state, stateid, err); + return nfs4_handle_delegation_recall_error(server, state, stateid, fl, err); } struct nfs_release_lockowner_data { diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c index e4f4a09ed9f4..91a4d4eeb235 100644 --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -1482,6 +1482,7 @@ static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_ struct inode *inode = state->inode; struct nfs_inode *nfsi = NFS_I(inode); struct file_lock *fl; + struct nfs4_lock_state *lsp; int status = 0; struct file_lock_context *flctx = inode->i_flctx; struct list_head *list; @@ -1522,7 +1523,9 @@ static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_ case -NFS4ERR_DENIED: case -NFS4ERR_RECLAIM_BAD: case -NFS4ERR_RECLAIM_CONFLICT: - /* kill_proc(fl->fl_pid, SIGLOST, 1); */ + lsp = fl->fl_u.nfs4_fl.owner; + if (lsp) + set_bit(NFS_LOCK_LOST, &lsp->ls_flags); status = 0; } spin_lock(&flctx->flc_lock);