On Wed, May 27, 2009 at 02:32:47PM +0400, Smirnov, Alexander wrote:
> Hello everybody,
>
> During test of NFS software I've found the problem in Linux kernel (nfsd)
>
> On the NFS4_WRITE request (data len=44), NFS server is responding with NFS4_OK (bytes written count = 0) that follows to
> cycliing in write request on client side.
Your problem looks the same as the following--could you confirm the fix?
--b.
From: Wei Yongjun <yjwei@xxxxxxxxxxxxxx>
To: nfsv4@xxxxxxxxxxxxx, linux-nfs@xxxxxxxxxxxxxxx,
"J. Bruce Fields" <bfields@xxxxxxxxxxxx>, Neil Brown <neilb@xxxxxxx>
Subject: [PATCH] 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@xxxxxxxxxxxxxx>
---
fs/nfsd/vfs.c | 6 +++---
1 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 6c68ffd..b660435 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -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;
--
1.5.3.8
--
To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
