NFS: Reduce the stack footprint of nfs_follow_mountpoint()

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

diff --git a/fs/nfs/namespace.c b/fs/nfs/namespace.c
index 7888cf36022d2dee78b983ff216a8371ee89164c..db6aa3673cf33b2d720b65ceb728a8a6e3244ab5 100644 (file)
--- a/fs/nfs/namespace.c
+++ b/fs/nfs/namespace.c
@@ -105,8 +105,8 @@ static void * nfs_follow_mountpoint(struct dentry *dentry, struct nameidata *nd)
        struct vfsmount *mnt;
        struct nfs_server *server = NFS_SERVER(dentry->d_inode);
        struct dentry *parent;
-       struct nfs_fh fh;
-       struct nfs_fattr fattr;
+       struct nfs_fh *fh = NULL;
+       struct nfs_fattr *fattr = NULL;
        int err;
 
        dprintk("--> nfs_follow_mountpoint()\n");
@@ -115,6 +115,12 @@ static void * nfs_follow_mountpoint(struct dentry *dentry, struct nameidata *nd)
        if (IS_ROOT(dentry))
                goto out_err;
 
+       err = -ENOMEM;
+       fh = nfs_alloc_fhandle();
+       fattr = nfs_alloc_fattr();
+       if (fh == NULL || fattr == NULL)
+               goto out_err;
+
        dprintk("%s: enter\n", __func__);
        dput(nd->path.dentry);
        nd->path.dentry = dget(dentry);
@@ -123,16 +129,16 @@ static void * nfs_follow_mountpoint(struct dentry *dentry, struct nameidata *nd)
        parent = dget_parent(nd->path.dentry);
        err = server->nfs_client->rpc_ops->lookup(parent->d_inode,
                                                  &nd->path.dentry->d_name,
-                                                 &fh, &fattr);
+                                                 fh, fattr);
        dput(parent);
        if (err != 0)
                goto out_err;
 
-       if (fattr.valid & NFS_ATTR_FATTR_V4_REFERRAL)
+       if (fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL)
                mnt = nfs_do_refmount(nd->path.mnt, nd->path.dentry);
        else
-               mnt = nfs_do_submount(nd->path.mnt, nd->path.dentry, &fh,
-                                     &fattr);
+               mnt = nfs_do_submount(nd->path.mnt, nd->path.dentry, fh,
+                                     fattr);
        err = PTR_ERR(mnt);
        if (IS_ERR(mnt))
                goto out_err;
@@ -151,6 +157,8 @@ static void * nfs_follow_mountpoint(struct dentry *dentry, struct nameidata *nd)
        nd->path.dentry = dget(mnt->mnt_root);
        schedule_delayed_work(&nfs_automount_task, nfs_mountpoint_expiry_timeout);
 out:
+       nfs_free_fattr(fattr);
+       nfs_free_fhandle(fh);
        dprintk("%s: done, returned %d\n", __func__, err);
 
        dprintk("<-- nfs_follow_mountpoint() = %d\n", err);