Support to inject result for NOP so that we can inject failure from
userspace. It is very helpful for covering failure handling code in
io_uring core change.
With nop flags, it becomes possible to add more test features on NOP in
future.
Suggested-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
---
include/uapi/linux/io_uring.h | 8 ++++++++
io_uring/nop.c | 26 +++++++++++++++++++++-----
2 files changed, 29 insertions(+), 5 deletions(-)
diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h
index 922f29b07ccc..21e9cd604068 100644
--- a/include/uapi/linux/io_uring.h
+++ b/include/uapi/linux/io_uring.h
@@ -72,6 +72,7 @@ struct io_uring_sqe {
__u32 waitid_flags;
__u32 futex_flags;
__u32 install_fd_flags;
+ __u32 nop_flags;
};
__u64 user_data; /* data to be passed back at completion time */
/* pack this to avoid bogus arm OABI complaints */
@@ -413,6 +414,13 @@ enum io_uring_msg_ring_flags {
*/
#define IORING_FIXED_FD_NO_CLOEXEC (1U << 0)
+/*
+ * IORING_OP_NOP flags (sqe->nop_flags)
+ *
+ * IORING_NOP_INJECT_RESULT Inject result from sqe->result
+ */
+#define IORING_NOP_INJECT_RESULT (1U << 0)
+
/*
* IO completion data structure (Completion Queue Entry)
*/
diff --git a/io_uring/nop.c b/io_uring/nop.c
index 1a4e312dfe51..a5bcf3d6984f 100644
--- a/io_uring/nop.c
+++ b/io_uring/nop.c
@@ -10,18 +10,34 @@
#include "io_uring.h"
#include "nop.h"
+struct io_nop {
+ /* NOTE: kiocb has the file as the first member, so don't do it here */
+ struct file *file;
+ int result;
+};
+
int io_nop_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
{
- if (READ_ONCE(sqe->rw_flags))
+ unsigned int flags;
+ struct io_nop *nop = io_kiocb_to_cmd(req, struct io_nop);
+
+ flags = READ_ONCE(sqe->nop_flags);
+ if (flags & ~IORING_NOP_INJECT_RESULT)
return -EINVAL;
+
+ if (flags & IORING_NOP_INJECT_RESULT)
+ nop->result = READ_ONCE(sqe->len);
+ else
+ nop->result = 0;
return 0;
}
-/*
- * IORING_OP_NOP just posts a completion event, nothing else.
- */
int io_nop(struct io_kiocb *req, unsigned int issue_flags)
{
- io_req_set_res(req, 0, 0);
+ struct io_nop *nop = io_kiocb_to_cmd(req, struct io_nop);
+
+ if (nop->result < 0)
+ req_set_fail(req);
+ io_req_set_res(req, nop->result, 0);
return IOU_OK;
}
--
2.42.0
