[PATCH for-next 09/12] io_uring: accept retarget_rsrc support

[Dylan Yudaken <dylany@meta.com>]

Add can_retarget_rsrc handler for accept

Signed-off-by: Dylan Yudaken <dylany@meta.com>
---
 io_uring/net.c   | 15 +++++++++++++++
 io_uring/net.h   |  1 +
 io_uring/opdef.c |  1 +
 3 files changed, 17 insertions(+)

diff --git a/io_uring/net.c b/io_uring/net.c
index 0fa05ef52dd3..429176f3d191 100644
--- a/io_uring/net.c
+++ b/io_uring/net.c
@@ -30,6 +30,7 @@ struct io_accept {
 	int				flags;
 	u32				file_slot;
 	unsigned long			nofile;
+	int				retarget_fd;
 };
 
 struct io_socket {
@@ -1255,6 +1256,15 @@ void io_sendrecv_fail(struct io_kiocb *req)
 		req->cqe.flags |= IORING_CQE_F_MORE;
 }
 
+bool io_accept_can_retarget_rsrc(struct io_kiocb *req)
+{
+	struct io_accept *accept = io_kiocb_to_cmd(req, struct io_accept);
+
+	if (accept->retarget_fd < 0)
+		return false;
+	return io_file_peek_fixed(req, accept->retarget_fd) == req->file;
+}
+
 int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
 	struct io_accept *accept = io_kiocb_to_cmd(req, struct io_accept);
@@ -1285,6 +1295,11 @@ int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 		accept->flags = (accept->flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
 	if (flags & IORING_ACCEPT_MULTISHOT)
 		req->flags |= REQ_F_APOLL_MULTISHOT;
+
+	if (req->flags & REQ_F_FIXED_FILE)
+		accept->retarget_fd = req->cqe.fd;
+	else
+		accept->retarget_fd = -1;
 	return 0;
 }
 
diff --git a/io_uring/net.h b/io_uring/net.h
index 6b5719084494..67fafb94d7de 100644
--- a/io_uring/net.h
+++ b/io_uring/net.h
@@ -49,6 +49,7 @@ void io_sendrecv_fail(struct io_kiocb *req);
 
 int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe);
 int io_accept(struct io_kiocb *req, unsigned int issue_flags);
+bool io_accept_can_retarget_rsrc(struct io_kiocb *req);
 
 int io_socket_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe);
 int io_socket(struct io_kiocb *req, unsigned int issue_flags);
diff --git a/io_uring/opdef.c b/io_uring/opdef.c
index 1a0be5681c7b..7c94f1a4315a 100644
--- a/io_uring/opdef.c
+++ b/io_uring/opdef.c
@@ -207,6 +207,7 @@ const struct io_op_def io_op_defs[] = {
 #if defined(CONFIG_NET)
 		.prep			= io_accept_prep,
 		.issue			= io_accept,
+		.can_retarget_rsrc	= io_accept_can_retarget_rsrc,
 #else
 		.prep			= io_eopnotsupp_prep,
 #endif
-- 
2.30.2