1 files changed, 36 insertions, 24 deletions

diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index b8ed58bab8b1..638573968dcf 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -141,6 +141,40 @@ out:
         return err;
 }
 
+static void follow_to_parent(struct path *path)
+{
+        struct dentry *dp;
+
+        while (path->dentry == path->mnt->mnt_root && follow_up(path))
+                ;
+        dp = dget_parent(path->dentry);
+        dput(path->dentry);
+        path->dentry = dp;
+}
+
+static int nfsd_lookup_parent(struct svc_rqst *rqstp, struct dentry *dparent, struct svc_export **exp, struct dentry **dentryp)
+{
+        struct svc_export *exp2;
+        struct path path = {.mnt = mntget((*exp)->ex_path.mnt),
+                            .dentry = dget(dparent)};
+
+        follow_to_parent(&path);
+
+        exp2 = rqst_exp_parent(rqstp, &path);
+        if (PTR_ERR(exp2) == -ENOENT) {
+                *dentryp = dget(dparent);
+        } else if (IS_ERR(exp2)) {
+                path_put(&path);
+                return PTR_ERR(exp2);
+        } else {
+                *dentryp = dget(path.dentry);
+                exp_put(*exp);
+                *exp = exp2;
+        }
+        path_put(&path);
+        return 0;
+}
+
 __be32
 nfsd_lookup_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp,
                    const char *name, unsigned int len,
@@ -173,31 +207,9 @@ nfsd_lookup_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp,
                         dentry = dget(dparent); /* .. == . just like at / */
                 else {
                         /* checking mountpoint crossing is very different when stepping up */
-                        struct svc_export *exp2 = NULL;
-                        struct dentry *dp;
-                        struct path path = {.mnt = mntget(exp->ex_path.mnt),
-                                            .dentry = dget(dparent)};
-
-                        while (path.dentry == path.mnt->mnt_root &&
-                               follow_up(&path))
-                                ;
-                        dp = dget_parent(path.dentry);
-                        dput(path.dentry);
-                        path.dentry = dp;
-
-                        exp2 = rqst_exp_parent(rqstp, &path);
-                        if (PTR_ERR(exp2) == -ENOENT) {
-                                dentry = dget(dparent);
-                        } else if (IS_ERR(exp2)) {
-                                host_err = PTR_ERR(exp2);
-                                path_put(&path);
+                        host_err = nfsd_lookup_parent(rqstp, dparent, &exp, &dentry);
+                        if (host_err)
                                 goto out_nfserr;
-                        } else {
-                                dentry = dget(path.dentry);
-                                exp_put(exp);
-                                exp = exp2;
-                        }
-                        path_put(&path);
                 }
         } else {
                 fh_lock(fhp);