From patchwork Wed Jun 29 03:10:36 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Cody X-Patchwork-Id: 641789 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3rfSQq137Mz9s2G for ; Wed, 29 Jun 2016 13:12:35 +1000 (AEST) Received: from localhost ([::1]:40892 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bI5vV-00024h-0z for incoming@patchwork.ozlabs.org; Tue, 28 Jun 2016 23:12:33 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53345) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bI5ty-0008Gh-CR for qemu-devel@nongnu.org; Tue, 28 Jun 2016 23:11:01 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bI5tw-0002X0-8W for qemu-devel@nongnu.org; Tue, 28 Jun 2016 23:10:57 -0400 Received: from mx1.redhat.com ([209.132.183.28]:60901) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bI5ts-0002W7-E4; Tue, 28 Jun 2016 23:10:52 -0400 Received: from int-mx13.intmail.prod.int.phx2.redhat.com (int-mx13.intmail.prod.int.phx2.redhat.com [10.5.11.26]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 0CE7F552FE; Wed, 29 Jun 2016 03:10:52 +0000 (UTC) Received: from localhost (ovpn-112-97.phx2.redhat.com [10.3.112.97]) by int-mx13.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u5T3An7a030238 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA256 bits=256 verify=NO); Tue, 28 Jun 2016 23:10:51 -0400 From: Jeff Cody To: qemu-block@nongnu.org Date: Tue, 28 Jun 2016 23:10:36 -0400 Message-Id: <1467169844-18111-3-git-send-email-jcody@redhat.com> In-Reply-To: <1467169844-18111-1-git-send-email-jcody@redhat.com> References: <1467169844-18111-1-git-send-email-jcody@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.26 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.29]); Wed, 29 Jun 2016 03:10:52 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PULL 02/10] block/nfs: refuse readahead if cache.direct is on X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: peter.maydell@linaro.org, jcody@redhat.com, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Peter Lieven if we open a NFS export with disabled cache we should refuse the readahead feature as it will cache data inside libnfs. If a export was opened with readahead enabled it should futher not be allowed to disable the cache while running. Cc: qemu-stable@nongnu.org Signed-off-by: Peter Lieven Reviewed-by: Jeff Cody Message-id: 1463662083-20814-2-git-send-email-pl@kamp.de Signed-off-by: Jeff Cody --- block/nfs.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) diff --git a/block/nfs.c b/block/nfs.c index 9f51cc3..60be45e 100644 --- a/block/nfs.c +++ b/block/nfs.c @@ -1,7 +1,7 @@ /* * QEMU Block driver for native access to files on NFS shares * - * Copyright (c) 2014 Peter Lieven + * Copyright (c) 2014-2016 Peter Lieven * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal @@ -47,6 +47,7 @@ typedef struct NFSClient { bool has_zero_init; AioContext *aio_context; blkcnt_t st_blocks; + bool cache_used; } NFSClient; typedef struct NFSRPC { @@ -278,7 +279,7 @@ static void nfs_file_close(BlockDriverState *bs) } static int64_t nfs_client_open(NFSClient *client, const char *filename, - int flags, Error **errp) + int flags, Error **errp, int open_flags) { int ret = -EINVAL, i; struct stat st; @@ -330,12 +331,18 @@ static int64_t nfs_client_open(NFSClient *client, const char *filename, nfs_set_tcp_syncnt(client->context, val); #ifdef LIBNFS_FEATURE_READAHEAD } else if (!strcmp(qp->p[i].name, "readahead")) { + if (open_flags & BDRV_O_NOCACHE) { + error_setg(errp, "Cannot enable NFS readahead " + "if cache.direct = on"); + goto fail; + } if (val > QEMU_NFS_MAX_READAHEAD_SIZE) { error_report("NFS Warning: Truncating NFS readahead" " size to %d", QEMU_NFS_MAX_READAHEAD_SIZE); val = QEMU_NFS_MAX_READAHEAD_SIZE; } nfs_set_readahead(client->context, val); + client->cache_used = true; #endif #ifdef LIBNFS_FEATURE_DEBUG } else if (!strcmp(qp->p[i].name, "debug")) { @@ -418,7 +425,7 @@ static int nfs_file_open(BlockDriverState *bs, QDict *options, int flags, } ret = nfs_client_open(client, qemu_opt_get(opts, "filename"), (flags & BDRV_O_RDWR) ? O_RDWR : O_RDONLY, - errp); + errp, bs->open_flags); if (ret < 0) { goto out; } @@ -454,7 +461,7 @@ static int nfs_file_create(const char *url, QemuOpts *opts, Error **errp) total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0), BDRV_SECTOR_SIZE); - ret = nfs_client_open(client, url, O_CREAT, errp); + ret = nfs_client_open(client, url, O_CREAT, errp, 0); if (ret < 0) { goto out; } @@ -516,6 +523,11 @@ static int nfs_reopen_prepare(BDRVReopenState *state, return -EACCES; } + if ((state->flags & BDRV_O_NOCACHE) && client->cache_used) { + error_setg(errp, "Cannot disable cache if libnfs readahead is enabled"); + return -EINVAL; + } + /* Update cache for read-only reopens */ if (!(state->flags & BDRV_O_RDWR)) { ret = nfs_fstat(client->context, client->fh, &st);