NFS: Reduce the stack footprint of nfs_follow_mountpoint()

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

1 files changed, 14 insertions, 6 deletions

diff --git a/fs/nfs/namespace.c b/fs/nfs/namespace.c
index 7888cf36022d..db6aa3673cf3 100644
--- 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);