-static ssize_t do_copy_file_range(struct file *file_in, loff_t pos_in,
- struct file *file_out, loff_t pos_out,
- size_t len, unsigned int flags)
-{
- /*
- * Although we now allow filesystems to handle cross sb copy, passing
- * a file of the wrong filesystem type to filesystem driver can result
- * in an attempt to dereference the wrong type of ->private_data, so
- * avoid doing that until we really have a good reason. NFS defines
- * several different file_system_type structures, but they all end up
- * using the same ->copy_file_range() function pointer.
- */
- if (file_out->f_op->copy_file_range &&
- file_out->f_op->copy_file_range == file_in->f_op->copy_file_range)
- return file_out->f_op->copy_file_range(file_in, pos_in,
- file_out, pos_out,
- len, flags);
-
- return generic_copy_file_range(file_in, pos_in, file_out, pos_out, len,
- flags);
-}
-