[PATCH RFC POC 33/50] io_uring/zcrx: install the exported descriptor when the request returns

[Christian Brauner]

Rely on the fd exit path machinery.

Signed-off-by: Christian Brauner (Amutable) <brauner at kernel.org>
---
 io_uring/zcrx.c | 25 +++++++------------------
 1 file changed, 7 insertions(+), 18 deletions(-)

diff --git a/io_uring/zcrx.c b/io_uring/zcrx.c
index 1b3b11405dac..d458c614c765 100644
--- a/io_uring/zcrx.c
+++ b/io_uring/zcrx.c
@@ -795,8 +795,6 @@ static int zcrx_export(struct io_ring_ctx *ctx, struct io_zcrx_ifq *ifq,
 		       struct zcrx_ctrl *ctrl, void __user *arg)
 {
 	struct zcrx_ctrl_export *ce = &ctrl->zc_export;
-	struct file *file;
-	int fd;
 
 	if (!mem_is_zero(ce, sizeof(*ce)))
 		return -EINVAL;
@@ -804,27 +802,18 @@ static int zcrx_export(struct io_ring_ctx *ctx, struct io_zcrx_ifq *ifq,
 	refcount_inc(&ifq->refs);
 	refcount_inc(&ifq->user_refs);
 
-	file = anon_inode_create_getfile("[zcrx]", &zcrx_box_fops,
-					 ifq, O_CLOEXEC, NULL);
-	if (IS_ERR(file)) {
+	FD_PREPARE(fdf, O_CLOEXEC,
+		   anon_inode_create_getfile("[zcrx]", &zcrx_box_fops, ifq,
+					     O_CLOEXEC, NULL));
+	if (IS_ERR(fdf)) {
 		zcrx_unregister(ifq, NULL);
-		return PTR_ERR(file);
-	}
-
-	fd = get_unused_fd_flags(O_CLOEXEC);
-	if (fd < 0) {
-		fput(file);
-		return fd;
+		return PTR_ERR(fdf);
 	}
 
-	ce->zcrx_fd = fd;
-	if (copy_to_user(arg, ctrl, sizeof(*ctrl))) {
-		fput(file);
-		put_unused_fd(fd);
+	ce->zcrx_fd = fd_prepare_fd(fdf);
+	if (copy_to_user(arg, ctrl, sizeof(*ctrl)))
 		return -EFAULT;
-	}
 
-	fd_install(fd, file);
 	return 0;
 }
 

-- 
2.53.0