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'
(31dec2538e) 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>
This commit is contained in:
Wei Yongjun 2009-05-19 12:03:15 +08:00 committed by J. Bruce Fields
parent 59a3759d0f
commit a0d24b295a

View file

@ -1015,6 +1015,7 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
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);
}
@ -1060,10 +1061,9 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
}
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;