orangefs: wait_for_direct_io(): restore the position in iter when restarting

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

fs/orangefs/file.c

@@ -133,6 +133,7 @@ static ssize_t wait_for_direct_io(enum ORANGEFS_io_type type, struct inode *inod
 	struct orangefs_khandle *handle = &orangefs_inode->refn.khandle;
 	struct orangefs_bufmap *bufmap = NULL;
 	struct orangefs_kernel_op_s *new_op = NULL;
+	struct iov_iter saved = *iter;
 	int buffer_index = -1;
 	ssize_t ret;
 
@@ -211,6 +212,8 @@ static ssize_t wait_for_direct_io(enum ORANGEFS_io_type type, struct inode *inod
 	if (ret == -EAGAIN && op_state_purged(new_op)) {
 		orangefs_bufmap_put(bufmap, buffer_index);
 		buffer_index = -1;
+		if (type == ORANGEFS_IO_WRITE)
+			*iter = saved;
 		gossip_debug(GOSSIP_FILE_DEBUG,
 			     "%s:going to repopulate_shared_memory.\n",
 			     __func__);