[RFC net-next v3 26/29] io_uring: flush notifiers after sendzc

[Pavel Begunkov <asml.silence@xxxxxxxxx>]

Allow to flush notifiers as a part of sendzc request by setting
IORING_SENDZC_FLUSH flag. When the sendzc request succeedes it will
flush the used [active] notifier.

Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx>
---
 fs/io_uring.c                 | 7 +++++--
 include/uapi/linux/io_uring.h | 1 +
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 70b1f77ac64e..f5fe2ab5622a 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -6581,7 +6581,7 @@ static int io_send(struct io_kiocb *req, unsigned int issue_flags)
 	return 0;
 }
 
-#define IO_SENDZC_VALID_FLAGS IORING_SENDZC_FIXED_BUF
+#define IO_SENDZC_VALID_FLAGS (IORING_SENDZC_FIXED_BUF|IORING_SENDZC_FLUSH)
 
 static int io_sendzc_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
@@ -6685,7 +6685,10 @@ static int io_sendzc(struct io_kiocb *req, unsigned int issue_flags)
 	msg.msg_ubuf = &notif->uarg;
 	ret = sock_sendmsg(sock, &msg);
 
-	if (unlikely(ret < min_ret)) {
+	if (likely(ret >= min_ret)) {
+		if (req->msgzc.zc_flags & IORING_SENDZC_FLUSH)
+			io_notif_slot_flush_submit(notif_slot, 0);
+	} else {
 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
 			return -EAGAIN;
 		if (ret == -ERESTARTSYS)
diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h
index 69100aa71448..7d77d90a5f8a 100644
--- a/include/uapi/linux/io_uring.h
+++ b/include/uapi/linux/io_uring.h
@@ -279,6 +279,7 @@ enum {
  */
 enum {
 	IORING_SENDZC_FIXED_BUF		= (1U << 0),
+	IORING_SENDZC_FLUSH		= (1U << 1),
 };
 
 /*
-- 
2.36.1