VFS: unexport lock_rename(), lock_rename_child(), unlock_rename()

These three function are now only used in namei.c, so they don't need to
be exported.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neil@brown.name>
Link: https://patch.msgid.link/20260224222542.3458677-16-neilb@ownmail.net
Signed-off-by: Christian Brauner <brauner@kernel.org>

Author: neilbrown

Documentation/filesystems/porting.rst

@@ -1368,3 +1368,10 @@ lifetime, consider using inode_set_cached_link() instead.
 
 lookup_one_qstr_excl() is no longer exported - use start_creating() or
 similar.
+---
+
+** mandatory**
+
+lock_rename(), lock_rename_child(), unlock_rename() are no
+longer available.  Use start_renaming() or similar.
+

fs/namei.c

@@ -3775,7 +3775,7 @@ static struct dentry *lock_two_directories(struct dentry *p1, struct dentry *p2)
 /*
  * p1 and p2 should be directories on the same fs.
  */
-struct dentry *lock_rename(struct dentry *p1, struct dentry *p2)
+static struct dentry *lock_rename(struct dentry *p1, struct dentry *p2)
 {
 	if (p1 == p2) {
 		inode_lock_nested(p1->d_inode, I_MUTEX_PARENT);
@@ -3785,12 +3785,11 @@ struct dentry *lock_rename(struct dentry *p1, struct dentry *p2)
 	mutex_lock(&p1->d_sb->s_vfs_rename_mutex);
 	return lock_two_directories(p1, p2);
 }
-EXPORT_SYMBOL(lock_rename);
 
 /*
  * c1 and p2 should be on the same fs.
  */
-struct dentry *lock_rename_child(struct dentry *c1, struct dentry *p2)
+static struct dentry *lock_rename_child(struct dentry *c1, struct dentry *p2)
 {
 	if (READ_ONCE(c1->d_parent) == p2) {
 		/*
@@ -3827,17 +3826,15 @@ struct dentry *lock_rename_child(struct dentry *c1, struct dentry *p2)
 	mutex_unlock(&c1->d_sb->s_vfs_rename_mutex);
 	return NULL;
 }
-EXPORT_SYMBOL(lock_rename_child);
 
-void unlock_rename(struct dentry *p1, struct dentry *p2)
+static void unlock_rename(struct dentry *p1, struct dentry *p2)
 {
 	inode_unlock(p1->d_inode);
 	if (p1 != p2) {
 		inode_unlock(p2->d_inode);
 		mutex_unlock(&p1->d_sb->s_vfs_rename_mutex);
 	}
 }
-EXPORT_SYMBOL(unlock_rename);
 
 /**
  * __start_renaming - lookup and lock names for rename

include/linux/namei.h

@@ -165,9 +165,6 @@ extern int follow_down_one(struct path *);
 extern int follow_down(struct path *path, unsigned int flags);
 extern int follow_up(struct path *);
 
-extern struct dentry *lock_rename(struct dentry *, struct dentry *);
-extern struct dentry *lock_rename_child(struct dentry *, struct dentry *);
-extern void unlock_rename(struct dentry *, struct dentry *);
 int start_renaming(struct renamedata *rd, int lookup_flags,
 		   struct qstr *old_last, struct qstr *new_last);
 int start_renaming_dentry(struct renamedata *rd, int lookup_flags,