From patchwork Thu Jan 22 23:35:53 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Haynes X-Patchwork-Id: 5689531 Return-Path: X-Original-To: patchwork-linux-nfs@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 1B76AC058E for ; Thu, 22 Jan 2015 23:37:25 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 391FF2028D for ; Thu, 22 Jan 2015 23:37:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4C74920274 for ; Thu, 22 Jan 2015 23:37:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754440AbbAVXhU (ORCPT ); Thu, 22 Jan 2015 18:37:20 -0500 Received: from mail-pd0-f174.google.com ([209.85.192.174]:57289 "EHLO mail-pd0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754290AbbAVXhT (ORCPT ); Thu, 22 Jan 2015 18:37:19 -0500 Received: by mail-pd0-f174.google.com with SMTP id ft15so4612991pdb.5 for ; Thu, 22 Jan 2015 15:37:18 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=U5Nn27nXeG/Pw1hZsrw0hf8F2smqiCVnDxo2W19km8Q=; b=GTIP9xQAgqK8xWrrlSgxN5pWrq4bxu8eiR8eTSx1wlTtwIWkRW/oyf5e7MB9kNsLyc hahXRrCNPuvbU7QGUEcdQhqO82EAwBq51iEZOJKyVWgoJl3TF4H2ncWXSBTb8TEcRJSd uEhcfuwCfApaMGlaXSfoaKoyy+l3Wrthtl0wWvXh7w2kkvE3gOCzr/cokyF4/5JKThFs uMEpWsco0eB501S9GsaS8uASa3UE9FpqUfcy1TzsIjOGA2TJKy+6VJ8YFSPGFqVcutJU tl0Dh2C68S1nirjKfxbPMt7D23jv2Cct5Ql0RWKfxUerav6/dI92LqwsnWlcA5UPpL7X lHkQ== X-Gm-Message-State: ALoCoQlolnvWTlb0bJxl8FNU2AhijzlUHlQww73uZHiBpM1i+cKptAsPGbFZVSW07/4KK7oBZtUW X-Received: by 10.66.55.104 with SMTP id r8mr6163251pap.75.1421969838555; Thu, 22 Jan 2015 15:37:18 -0800 (PST) Received: from localhost.localdomain ([50.242.95.105]) by mx.google.com with ESMTPSA id fu1sm366817pdb.80.2015.01.22.15.37.17 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 22 Jan 2015 15:37:18 -0800 (PST) From: Tom Haynes X-Google-Original-From: Tom Haynes To: Trond Myklebust Cc: Linux NFS Mailing list Subject: [PATCH v5 21/51] nfs41: serialize first layoutget of a file Date: Thu, 22 Jan 2015 15:35:53 -0800 Message-Id: <1421969783-92997-22-git-send-email-loghyr@primarydata.com> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1421969783-92997-1-git-send-email-loghyr@primarydata.com> References: <1421969783-92997-1-git-send-email-loghyr@primarydata.com> Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Peng Tao Per RFC 5661 Errata 3208: | A client MAY always forget its layout state and associated | layout stateid at any time (See also section 12.5.5.1). | In such case, the client MUST use a non-layout stateid for the next | LAYOUTGET operation. This will signal the server that the client has | no more layouts on the file and its respective layout state can be | released before issuing a new layout in response to LAYOUTGET. In order to make such a signal unique to server, client needs to serialize all layoutgets using non-layout stateid. We implement this by serializing layoutgets when client has no layout segments at hand. Signed-off-by: Peng Tao Signed-off-by: Tom Haynes --- fs/nfs/pnfs.c | 35 +++++++++++++++++++++++++++++++---- fs/nfs/pnfs.h | 1 + 2 files changed, 32 insertions(+), 4 deletions(-) diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c index fa00b56..7e1bac1 100644 --- a/fs/nfs/pnfs.c +++ b/fs/nfs/pnfs.c @@ -1288,6 +1288,7 @@ pnfs_update_layout(struct inode *ino, struct nfs_client *clp = server->nfs_client; struct pnfs_layout_hdr *lo; struct pnfs_layout_segment *lseg = NULL; + bool first; if (!pnfs_enabled_sb(NFS_SERVER(ino))) goto out; @@ -1295,6 +1296,8 @@ pnfs_update_layout(struct inode *ino, if (pnfs_within_mdsthreshold(ctx, ino, iomode)) goto out; +lookup_again: + first = false; spin_lock(&ino->i_lock); lo = pnfs_find_alloc_layout(ino, ctx, gfp_flags); if (lo == NULL) { @@ -1312,10 +1315,27 @@ pnfs_update_layout(struct inode *ino, if (pnfs_layout_io_test_failed(lo, iomode)) goto out_unlock; - /* Check to see if the layout for the given range already exists */ - lseg = pnfs_find_lseg(lo, &arg); - if (lseg) - goto out_unlock; + first = list_empty(&lo->plh_segs); + if (first) { + /* The first layoutget for the file. Need to serialize per + * RFC 5661 Errata 3208. + */ + if (test_and_set_bit(NFS_LAYOUT_FIRST_LAYOUTGET, + &lo->plh_flags)) { + spin_unlock(&ino->i_lock); + wait_on_bit(&lo->plh_flags, NFS_LAYOUT_FIRST_LAYOUTGET, + TASK_UNINTERRUPTIBLE); + pnfs_put_layout_hdr(lo); + goto lookup_again; + } + } else { + /* Check to see if the layout for the given range + * already exists + */ + lseg = pnfs_find_lseg(lo, &arg); + if (lseg) + goto out_unlock; + } if (pnfs_layoutgets_blocked(lo, 0)) goto out_unlock; @@ -1343,6 +1363,13 @@ pnfs_update_layout(struct inode *ino, lseg = send_layoutget(lo, ctx, &arg, gfp_flags); atomic_dec(&lo->plh_outstanding); out_put_layout_hdr: + if (first) { + unsigned long *bitlock = &lo->plh_flags; + + clear_bit_unlock(NFS_LAYOUT_FIRST_LAYOUTGET, bitlock); + smp_mb__after_atomic(); + wake_up_bit(bitlock, NFS_LAYOUT_FIRST_LAYOUTGET); + } pnfs_put_layout_hdr(lo); out: dprintk("%s: inode %s/%llu pNFS layout segment %s for " diff --git a/fs/nfs/pnfs.h b/fs/nfs/pnfs.h index 70ffec1..a9a7b26 100644 --- a/fs/nfs/pnfs.h +++ b/fs/nfs/pnfs.h @@ -95,6 +95,7 @@ enum { NFS_LAYOUT_ROC, /* some lseg had roc bit set */ NFS_LAYOUT_RETURN, /* Return this layout ASAP */ NFS_LAYOUT_INVALID_STID, /* layout stateid id is invalid */ + NFS_LAYOUT_FIRST_LAYOUTGET, /* Serialize first layoutget */ }; enum layoutdriver_policy_flags {