+ /*
+ * Only $DATA attributes can be encrypted and only unnamed $DATA
+ * attributes can be compressed. Index root can have the flags set but
+ * this means to create compressed/encrypted files, not that the
+ * attribute is compressed/encrypted.
+ */
+ if (ni->type != AT_INDEX_ROOT) {
+ /* If file is encrypted, deny access, just like NT4. */
+ if (NInoEncrypted(ni)) {
+ unlock_page(page);
+ BUG_ON(ni->type != AT_DATA);
+ ntfs_debug("Denying write access to encrypted "
+ "file.");
+ return -EACCES;
+ }
+ /* Compressed data streams are handled in compress.c. */
+ if (NInoNonResident(ni) && NInoCompressed(ni)) {
+ BUG_ON(ni->type != AT_DATA);
+ BUG_ON(ni->name_len);
+ // TODO: Implement and replace this with
+ // return ntfs_write_compressed_block(page);
+ unlock_page(page);
+ ntfs_error(vi->i_sb, "Writing to compressed files is "
+ "not supported yet. Sorry.");
+ return -EOPNOTSUPP;
+ }
+ // TODO: Implement and remove this check.
+ if (NInoNonResident(ni) && NInoSparse(ni)) {
+ unlock_page(page);
+ ntfs_error(vi->i_sb, "Writing to sparse files is not "
+ "supported yet. Sorry.");
+ return -EOPNOTSUPP;
+ }
+ }