From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758155AbZIPWTG (ORCPT ); Wed, 16 Sep 2009 18:19:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757667AbZIPWSr (ORCPT ); Wed, 16 Sep 2009 18:18:47 -0400 Received: from kroah.org ([198.145.64.141]:49819 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757167AbZIPWSh (ORCPT ); Wed, 16 Sep 2009 18:18:37 -0400 X-Mailbox-Line: From gregkh@mini.kroah.org Wed Sep 16 15:15:07 2009 Message-Id: <20090916221507.102426758@mini.kroah.org> User-Agent: quilt/0.48-1 Date: Wed, 16 Sep 2009 15:13:30 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, "J. Bruce Fields" , Wei Yongjun , Chuck Ebbert Subject: [patch 10/10] nfsd: fix hung up of nfs client while sync write data to nfs server References: <20090916221320.283781925@mini.kroah.org> Content-Disposition: inline; filename=nfsd-fix-hung-up-of-nfs-client-while-sync-write-data-to-nfs-server.patch In-Reply-To: <20090916221529.GA28162@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.27-stable review patch. If anyone has any objections, please let us know. ------------------ From: Wei Yongjun commit a0d24b295aed7a9daf4ca36bd4784e4d40f82303 upstream. nfsd: fix hung up of nfs client while sync write data to nfs server Commit 'Short write in nfsd becomes a full write to the client' (31dec2538e45e9fff2007ea1f4c6bae9f78db724) broken the sync write. With the following commands to reproduce: $ mount -t nfs -o sync 192.168.0.21:/nfsroot /mnt $ cd /mnt $ echo aaaa > temp.txt Then nfs client is hung up. In SYNC mode the server alaways return the write count 0 to the client. This is because the value of host_err in nfsd_vfs_write() will be overwrite in SYNC mode by 'host_err=nfsd_sync(file);', and then we return host_err(which is now 0) as write count. This patch fixed the problem. Signed-off-by: Wei Yongjun Signed-off-by: J. Bruce Fields Cc: Chuck Ebbert Signed-off-by: Greg Kroah-Hartman --- fs/nfsd/vfs.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -1003,6 +1003,7 @@ nfsd_vfs_write(struct svc_rqst *rqstp, s host_err = vfs_writev(file, (struct iovec __user *)vec, vlen, &offset); set_fs(oldfs); if (host_err >= 0) { + *cnt = host_err; nfsdstats.io_write += host_err; fsnotify_modify(file->f_path.dentry); } @@ -1048,10 +1049,9 @@ nfsd_vfs_write(struct svc_rqst *rqstp, s } dprintk("nfsd: write complete host_err=%d\n", host_err); - if (host_err >= 0) { + if (host_err >= 0) err = 0; - *cnt = host_err; - } else + else err = nfserrno(host_err); out: return err;