From: Trond Myklebust <Trond.Myklebust@netapp.com>
Date: Fri, 23 Oct 2009 18:46:42 +0000 (-0400)
Subject: NFSv4: Fix a bug when the server returns NFS4ERR_RESOURCE
X-Git-Tag: v2.6.31.6~19
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4886f073309eeb9d99d9f05d944f8b0874c60bbd;p=thirdparty%2Fkernel%2Fstable.git

NFSv4: Fix a bug when the server returns NFS4ERR_RESOURCE

commit 52567b03ca38b6e556ced450d64dba8d66e23b0e upstream.

RFC 3530 states that when we recieve the error NFS4ERR_RESOURCE, we are not
supposed to bump the sequence number on OPEN, LOCK, LOCKU, CLOSE, etc
operations. The problem is that we map that error into EREMOTEIO in the XDR
layer, and so the NFSv4 middle-layer routines like seqid_mutating_err(),
and nfs_increment_seqid() don't recognise it.

The fix is to defer the mapping until after the middle layers have
processed the error.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 6917311f201c3..6c1534cdef1fe 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -71,12 +71,17 @@ static int _nfs4_proc_getattr(struct nfs_server *server, struct nfs_fh *fhandle,
 /* Prevent leaks of NFSv4 errors into userland */
 static int nfs4_map_errors(int err)
 {
-	if (err < -1000) {
+	if (err >= -1000)
+		return err;
+	switch (err) {
+	case -NFS4ERR_RESOURCE:
+		return -EREMOTEIO;
+	default:
 		dprintk("%s could not handle NFSv4 error %d\n",
 				__func__, -err);
-		return -EIO;
+		break;
 	}
-	return err;
+	return -EIO;
 }
 
 /*
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 617273e7d47f5..f4c9e1a0d9ce1 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -5406,7 +5406,6 @@ static struct {
 	{ NFS4ERR_SERVERFAULT,	-ESERVERFAULT	},
 	{ NFS4ERR_BADTYPE,	-EBADTYPE	},
 	{ NFS4ERR_LOCKED,	-EAGAIN		},
-	{ NFS4ERR_RESOURCE,	-EREMOTEIO	},
 	{ NFS4ERR_SYMLINK,	-ELOOP		},
 	{ NFS4ERR_OP_ILLEGAL,	-EOPNOTSUPP	},
 	{ NFS4ERR_DEADLOCK,	-EDEADLK	},