nfsd4: fix error return when pseudoroot missing

We really shouldn't hit this case at all, and forthcoming kernel and
nfs-utils changes should eliminate this case; if it does happen,
consider it a bug rather than reporting an error that doesn't really
make sense for the operation (since there's no reason for a server to be
accepting v4 traffic yet have no root filehandle).

Also move some exp_pseudoroot code into a helper function while we're
here.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

diff --git a/fs/nfsd/export.c b/fs/nfsd/export.c
index c1c9e03..b73baba 100644 (file)
--- a/fs/nfsd/export.c
+++ b/fs/nfsd/export.c
@@ -1320,6 +1320,23 @@ rqst_exp_parent(struct svc_rqst *rqstp, struct path *path)
        return exp;
 }
 
+static struct svc_export *find_fsidzero_export(struct svc_rqst *rqstp)
+{
+       struct svc_export *exp;
+       u32 fsidv[2];
+
+       mk_fsid(FSID_NUM, fsidv, 0, 0, 0, NULL);
+
+       exp = rqst_exp_find(rqstp, FSID_NUM, fsidv);
+       /*
+        * We shouldn't have accepting an nfsv4 request at all if we
+        * don't have a pseudoexport!:
+        */
+       if (IS_ERR(exp) && PTR_ERR(exp) == -ENOENT)
+               exp = ERR_PTR(-ESERVERFAULT);
+       return exp;
+}
+
 /*
  * Called when we need the filehandle for the root of the pseudofs,
  * for a given NFSv4 client.   The root is defined to be the
@@ -1330,11 +1347,8 @@ exp_pseudoroot(struct svc_rqst *rqstp, struct svc_fh *fhp)
 {
        struct svc_export *exp;
        __be32 rv;
-       u32 fsidv[2];
-
-       mk_fsid(FSID_NUM, fsidv, 0, 0, 0, NULL);
 
-       exp = rqst_exp_find(rqstp, FSID_NUM, fsidv);
+       exp = find_fsidzero_export(rqstp);
        if (IS_ERR(exp))
                return nfserrno(PTR_ERR(exp));
        rv = fh_compose(fhp, exp, exp->ex_path.dentry, NULL);

diff --git a/fs/nfsd/nfsproc.c b/fs/nfsd/nfsproc.c
index 0eb9c82..c5393d1 100644 (file)
--- a/fs/nfsd/nfsproc.c
+++ b/fs/nfsd/nfsproc.c
@@ -758,6 +758,7 @@ nfserrno (int errno)
                { nfserr_io, -ETXTBSY },
                { nfserr_notsupp, -EOPNOTSUPP },
                { nfserr_toosmall, -ETOOSMALL },
+               { nfserr_serverfault, -ESERVERFAULT },
        };
        int     i;