switch vfs_path_lookup() to struct path

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/namei.c

@@ -1575,16 +1575,22 @@ int kern_path(const char *name, unsigned int flags, struct path *path)
  * @mnt: pointer to vfs mount of the base directory
  * @name: pointer to file name
  * @flags: lookup flags
- * @nd: pointer to nameidata
+ * @path: pointer to struct path to fill
  */
 int vfs_path_lookup(struct dentry *dentry, struct vfsmount *mnt,
 		    const char *name, unsigned int flags,
-		    struct nameidata *nd)
+		    struct path *path)
 {
-	nd->root.dentry = dentry;
-	nd->root.mnt = mnt;
+	struct nameidata nd;
+	int err;
+	nd.root.dentry = dentry;
+	nd.root.mnt = mnt;
+	BUG_ON(flags & LOOKUP_PARENT);
 	/* the first argument of do_path_lookup() is ignored with LOOKUP_ROOT */
-	return do_path_lookup(AT_FDCWD, name, flags | LOOKUP_ROOT, nd);
+	err = do_path_lookup(AT_FDCWD, name, flags | LOOKUP_ROOT, &nd);
+	if (!err)
+		*path = nd.path;
+	return err;
 }
 
 static struct dentry *__lookup_hash(struct qstr *name,

fs/nfs/cache_lib.c

@@ -113,19 +113,18 @@ int nfs_cache_wait_for_upcall(struct nfs_cache_defer_req *dreq)
 
 int nfs_cache_register(struct cache_detail *cd)
 {
-	struct nameidata nd;
 	struct vfsmount *mnt;
+	struct path path;
 	int ret;
 
 	mnt = rpc_get_mount();
 	if (IS_ERR(mnt))
 		return PTR_ERR(mnt);
-	ret = vfs_path_lookup(mnt->mnt_root, mnt, "/cache", 0, &nd);
+	ret = vfs_path_lookup(mnt->mnt_root, mnt, "/cache", 0, &path);
 	if (ret)
 		goto err;
-	ret = sunrpc_cache_register_pipefs(nd.path.dentry,
-			cd->name, 0600, cd);
-	path_put(&nd.path);
+	ret = sunrpc_cache_register_pipefs(path.dentry, cd->name, 0600, cd);
+	path_put(&path);
 	if (!ret)
 		return ret;
 err:

fs/nfs/super.c

@@ -2773,16 +2773,12 @@ static void nfs_referral_loop_unprotect(void)
 static struct dentry *nfs_follow_remote_path(struct vfsmount *root_mnt,
 		const char *export_path)
 {
-	struct nameidata *nd = NULL;
 	struct mnt_namespace *ns_private;
 	struct super_block *s;
 	struct dentry *dentry;
+	struct path path;
 	int ret;
 
-	nd = kmalloc(sizeof(*nd), GFP_KERNEL);
-	if (nd == NULL)
-		return ERR_PTR(-ENOMEM);
-
 	ns_private = create_mnt_ns(root_mnt);
 	ret = PTR_ERR(ns_private);
 	if (IS_ERR(ns_private))
@@ -2793,7 +2789,7 @@ static struct dentry *nfs_follow_remote_path(struct vfsmount *root_mnt,
 		goto out_put_mnt_ns;
 
 	ret = vfs_path_lookup(root_mnt->mnt_root, root_mnt,
-			export_path, LOOKUP_FOLLOW, nd);
+			export_path, LOOKUP_FOLLOW, &path);
 
 	nfs_referral_loop_unprotect();
 	put_mnt_ns(ns_private);
@@ -2801,12 +2797,11 @@ static struct dentry *nfs_follow_remote_path(struct vfsmount *root_mnt,
 	if (ret != 0)
 		goto out_err;
 
-	s = nd->path.mnt->mnt_sb;
+	s = path.mnt->mnt_sb;
 	atomic_inc(&s->s_active);
-	dentry = dget(nd->path.dentry);
+	dentry = dget(path.dentry);
 
-	path_put(&nd->path);
-	kfree(nd);
+	path_put(&path);
 	down_write(&s->s_umount);
 	return dentry;
 out_put_mnt_ns:
@@ -2814,7 +2809,6 @@ static struct dentry *nfs_follow_remote_path(struct vfsmount *root_mnt,
 out_mntput:
 	mntput(root_mnt);
 out_err:
-	kfree(nd);
 	return ERR_PTR(ret);
 }
 

include/linux/namei.h

@@ -78,7 +78,7 @@ extern struct dentry *kern_path_create(int, const char *, struct path *, int);
 extern struct dentry *user_path_create(int, const char __user *, struct path *, int);
 extern int kern_path_parent(const char *, struct nameidata *);
 extern int vfs_path_lookup(struct dentry *, struct vfsmount *,
-			   const char *, unsigned int, struct nameidata *);
+			   const char *, unsigned int, struct path *);
 
 extern struct file *lookup_instantiate_filp(struct nameidata *nd, struct dentry *dentry,
 		int (*open)(struct inode *, struct file *));

net/sunrpc/clnt.c

@@ -97,8 +97,7 @@ static int
 rpc_setup_pipedir(struct rpc_clnt *clnt, char *dir_name)
 {
 	static uint32_t clntid;
-	struct nameidata nd;
-	struct path path;
+	struct path path, dir;
 	char name[15];
 	struct qstr q = {
 		.name = name,
@@ -113,7 +112,7 @@ rpc_setup_pipedir(struct rpc_clnt *clnt, char *dir_name)
 	path.mnt = rpc_get_mount();
 	if (IS_ERR(path.mnt))
 		return PTR_ERR(path.mnt);
-	error = vfs_path_lookup(path.mnt->mnt_root, path.mnt, dir_name, 0, &nd);
+	error = vfs_path_lookup(path.mnt->mnt_root, path.mnt, dir_name, 0, &dir);
 	if (error)
 		goto err;
 
@@ -121,7 +120,7 @@ rpc_setup_pipedir(struct rpc_clnt *clnt, char *dir_name)
 		q.len = snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++);
 		name[sizeof(name) - 1] = '\0';
 		q.hash = full_name_hash(q.name, q.len);
-		path.dentry = rpc_create_client_dir(nd.path.dentry, &q, clnt);
+		path.dentry = rpc_create_client_dir(dir.dentry, &q, clnt);
 		if (!IS_ERR(path.dentry))
 			break;
 		error = PTR_ERR(path.dentry);
@@ -132,11 +131,11 @@ rpc_setup_pipedir(struct rpc_clnt *clnt, char *dir_name)
 			goto err_path_put;
 		}
 	}
-	path_put(&nd.path);
+	path_put(&dir);
 	clnt->cl_path = path;
 	return 0;
 err_path_put:
-	path_put(&nd.path);
+	path_put(&dir);
 err:
 	rpc_put_mount();
 	return error;