[PATCH 3/4] io_uring/msg_ring: split fd installing into a helper

[Jens Axboe <axboe@xxxxxxxxx>]

No functional changes in this patch, just in preparation for needing to
complete the fd install with the ctx lock already held.

Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
---
 io_uring/msg_ring.c | 26 ++++++++++++++++++--------
 1 file changed, 18 insertions(+), 8 deletions(-)

diff --git a/io_uring/msg_ring.c b/io_uring/msg_ring.c
index d1f66a40b4b4..9023b39fecef 100644
--- a/io_uring/msg_ring.c
+++ b/io_uring/msg_ring.c
@@ -173,25 +173,23 @@ static struct file *io_msg_grab_file(struct io_kiocb *req, unsigned int issue_fl
 	return file;
 }
 
-static int io_msg_install_complete(struct io_kiocb *req, unsigned int issue_flags)
+static int __io_msg_install_complete(struct io_kiocb *req)
 {
 	struct io_ring_ctx *target_ctx = req->file->private_data;
 	struct io_msg *msg = io_kiocb_to_cmd(req, struct io_msg);
 	struct file *src_file = msg->src_file;
 	int ret;
 
-	if (unlikely(io_double_lock_ctx(target_ctx, issue_flags)))
-		return -EAGAIN;
-
 	ret = __io_fixed_fd_install(target_ctx, src_file, msg->dst_fd);
 	if (ret < 0)
-		goto out_unlock;
+		return ret;
 
 	msg->src_file = NULL;
 	req->flags &= ~REQ_F_NEED_CLEANUP;
 
 	if (msg->flags & IORING_MSG_RING_CQE_SKIP)
-		goto out_unlock;
+		return ret;
+
 	/*
 	 * If this fails, the target still received the file descriptor but
 	 * wasn't notified of the fact. This means that if this request
@@ -199,8 +197,20 @@ static int io_msg_install_complete(struct io_kiocb *req, unsigned int issue_flag
 	 * later IORING_OP_MSG_RING delivers the message.
 	 */
 	if (!io_post_aux_cqe(target_ctx, msg->user_data, ret, 0))
-		ret = -EOVERFLOW;
-out_unlock:
+		return -EOVERFLOW;
+
+	return ret;
+}
+
+static int io_msg_install_complete(struct io_kiocb *req, unsigned int issue_flags)
+{
+	struct io_ring_ctx *target_ctx = req->file->private_data;
+	int ret;
+
+	if (unlikely(io_double_lock_ctx(target_ctx, issue_flags)))
+		return -EAGAIN;
+
+	ret = __io_msg_install_complete(req);
 	io_double_unlock_ctx(target_ctx);
 	return ret;
 }
-- 
2.43.0