+ /* If extent has less than EXT4_EXT_ZERO_LEN zerout directly */
+ if (allocated <= EXT4_EXT_ZERO_LEN) {
+ /* Mark first half uninitialized.
+ * Mark second half initialized and zero out the
+ * initialized extent
+ */
+ ex->ee_block = orig_ex.ee_block;
+ ex->ee_len = cpu_to_le16(ee_len - allocated);
+ ext4_ext_mark_uninitialized(ex);
+ ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
+ ext4_ext_dirty(handle, inode, path + depth);
+
+ ex3 = &newex;
+ ex3->ee_block = cpu_to_le32(iblock);
+ ext4_ext_store_pblock(ex3, newblock);
+ ex3->ee_len = cpu_to_le16(allocated);
+ err = ext4_ext_insert_extent(handle, inode, path, ex3);
+ if (err == -ENOSPC) {
+ err = ext4_ext_zeroout(inode, &orig_ex);
+ if (err)
+ goto fix_extent_len;
+ ex->ee_block = orig_ex.ee_block;
+ ex->ee_len = orig_ex.ee_len;
+ ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
+ ext4_ext_dirty(handle, inode, path + depth);
+ /* zeroed the full extent */
+ return allocated;
+
+ } else if (err)
+ goto fix_extent_len;
+
+ /*
+ * We need to zero out the second half because
+ * an fallocate request can update file size and
+ * converting the second half to initialized extent
+ * implies that we can leak some junk data to user
+ * space.
+ */
+ err = ext4_ext_zeroout(inode, ex3);
+ if (err) {
+ /*
+ * We should actually mark the
+ * second half as uninit and return error
+ * Insert would have changed the extent
+ */
+ depth = ext_depth(inode);
+ ext4_ext_drop_refs(path);
+ path = ext4_ext_find_extent(inode,
+ iblock, path);
+ if (IS_ERR(path)) {
+ err = PTR_ERR(path);
+ return err;
+ }
+ ex = path[depth].p_ext;
+ err = ext4_ext_get_access(handle, inode,
+ path + depth);
+ if (err)
+ return err;
+ ext4_ext_mark_uninitialized(ex);
+ ext4_ext_dirty(handle, inode, path + depth);
+ return err;
+ }
+
+ /* zeroed the second half */
+ return allocated;
+ }