lkml.org 
[lkml]   [2009]   [Sep]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Date
    From
    Subject[patch 10/10] nfsd: fix hung up of nfs client while sync write data to nfs server

    2.6.27-stable review patch. If anyone has any objections, please let us know.

    ------------------
    From: Wei Yongjun <yjwei@cn.fujitsu.com>

    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 <yjwei@cn.fujitsu.com>
    Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
    Cc: Chuck Ebbert <cebbert@redhat.com>
    Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

    ---
    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;



    \
     
     \ /
      Last update: 2009-09-17 00:23    [W:0.020 / U:0.552 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site